USMLE Step 2 CK-Neurology – Flashcards
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What is a stroke?
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acute onset of focal neurologic deficits resulting from disruption of cerebral circulation
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What is the glossopharyngeal (IX) cranial nerve responsible for?
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taste from the posterior third of the tongue, oropharyngeal sensation, swallowing (stylopharyngeus), salivation (parotid gland), monitoring carotid body and sinus chemo- and baroreceptors
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What is the facial nerve (VII) cranial nerve responsible for?
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facial movement, taste from the anterior two-thirds of the tongue, lacrimation, salivation (submandibular and sublingual glands), eyelid closing
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What is the vagus (X) cranial nerve responsible for?
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Taste from the epiglottic region, swallowing, palatal elevation, talking, thoracoabdominal, viscera, monitoring aortic arch chemo- and barorecptors
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What is Bell's palsy?
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complete destruction of the facial nucleus itself or its branchial efferent fibers (facial nerve proper). Peripheral ipsilateral facial paralysis w/ inability to close the eye on the involved side. Can occur idiopathically; gradual recovery is seen in most cases. Seen as a complication in AIDS, Lyme disease, Sarcoidosis, Tumors, and Diabetes
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What facial manifestation do UMN lesions have?
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lesion of the motor cortex or the connection btw the cortex and the facial nucleus. Contralateral paralysis of the lower face only
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What facial manifestation do LMN lesions have?
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ipsilateral paralysis of the upper and lower face
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What are the different types/etiologies of stroke?
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Atherosclerosis Lacunar infarcts Cardiac/aortic emboli: thromboemboli/atheroemboli/infectious emboli/paradoxical emboli Hypercoagulable states Craniocervical dissection Other: venous sinus thrombosis, sickle cell anemia, vasculitis
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Are strokes mostly ischemic or hemorrhagic?
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Mostly ischemic: 80% Hemorrhagic: 20%
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What are the different etiologies for cardiac/aortic emboli strokes?
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Thromboemboli (AF, ventricular hypokinesis, prosthetic valves, marantic endocarditis) Atheroemboli (aortic arch atherosclerosis) Infectious emboli (bacterial endocarditis) paradoxical emboli (via patent foramen ovale)
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What types of hypercoagulable states put pts at risk for strokes?
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antiphospholipid abs activated protein C resistance malignancy OCPs in the context of smoking
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What types of craniocervical dissection put pts at risk for stroke?
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trauma fibromuscular dysplasia (young females) inflammatory/infectious diseases
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What is the fxn of the lateral corticospinal tract?
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movement of contralateral limbs
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Where does the lateral corticospinal tract decussate?
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pyramidal, at the cervicomedullary jxn
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What is the origin of the lateral corticospinal tract?
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primary motor cortex
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What is the fxn of dorsal column medial lemniscus?
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fine touch, vibration, conscious proprioception
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Where does the dorsal column medial lemniscus decussate?
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arcuate fibers at the medulla
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What is the origin of the dorsal column medial lemniscus?
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Pacini's and Meissner's tactile disks, muscle spindles, and Golgi tendon organs
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What is the fxn of the spinothalamic tract?
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pain, temperature
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Where does the spinothalamic tract decussate?
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ventral white commissure at the spinal cord level
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What is the origin of the spinothalamic tract?
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free nerve endings, pain fibers
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What changes in tone are manifested in UMN lesions?
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spastic (increased tone); initially flaccid (decreased tone)
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What changes in tone are manifested in LMN lesions?
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flaccid (decreased tone)
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How are DTRs changed in UMN lesions?
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increased (initially decreased/normal) hyperreflexive
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How are DTRs changed in LMN lesions?
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decreased hyporeflexive
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How does a MCA stroke present?
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aphasia (dominant hemisphere) neglect (nondominant hemisphere) contralateral paresis sensory loss in the face and arm gaze preference toward the side of the lesion homonymous hemianopia.
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How does an ACA stroke present?
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contralateral paresis sensory loss in the leg cognitive or personality changes
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How does a PCA stroke present?
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homonymous hemianopia memory deficits dyslexia/alexia
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How does a basilar artery stroke present?
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coma "locked-in" syndrome cranial nerve palsies (eg. diplopia) apnea visual sx drop attacks dysphagia dysarthria vertigo "Crossed" weakness and sensory loss affecting the ipsilateral face and contralateral body
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How does a lacunar stroke present?
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pure motor or sensory stroke dysarthria-clumsy hand syndrome ataxic hemiparesis
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How does a TIA present?
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transient neurologic deficit that lasts <24hrs (most last <1hr) and is determined to be of ischemic in origin. Many TIAs are assoc w/ small, ASx strokes on diffusion-weight MRI
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What are the 4 deadly Ds of posterior circulation strokes?
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diplopia dizziness dysphagia dysarthria
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How are strokes dx?
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EMERGENT head CT w/o contrast to differentiate ischemic from hemorrhagic stroke and to identify potential candidates for thrombolytic tx MRI: identify early ischemic changes (diffusion-weighted MRI is sensitive for acute stroke) EKG: an echocardiogram if embolic stroke is suspected Vascular studies: intracranial and extracranial disease include carotid ultrasound, transcranial Doppler, MRA, and angiography Screen for hypercoagulable stages: w/ hx of thrombosis, in the setting of a first stroke, or in pts <50yo
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What nerve root is assoc w/ the biceps reflex?
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C5
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What nerve root is assoc w/ the triceps reflex?
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C7
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What nerve root is assoc w/ the patellar reflex?
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L4
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What nerve root is assoc w/ the achilles reflex?
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S1
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What does a positive Babinski indicate?
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sign of UMN lesion
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What types of lesions are seen in Poliomyelitis and Werdnig-Hoffman disease?
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LMN lesions only, due to destruction of anterior horns; flaccid paralysis
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What types of lesions are seen in MS?
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mostly white matter of cervical region; random and asymmetric lesions due to demyelination; scanning to speech, intention tremor, nystagmus
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What types of lesions are seen in ALS?
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combined UMN and LMN deficits w/ no sensory deficit; both UMN and LMN signs
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What types of lesions are seen in complete occlusion of ventral artery?
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spares dorsal columns and tract of Lissauer
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What types of lesions are seen in Tabes dorsalis (tertiary syphilis)?
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degernation of dorsal roots and dorsal columns; impaired proprioception, locomotor ataxia
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What types of lesions are seen in syringomyelia?
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crossing fibers of corticospinal tract damaged; bilateral loss of pain and temperature sensation
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What types of lesions are seen in vitamin B12 neuropathy and Friedreich's ataxia?
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demyelination of dorsal columns, lateral corticospinal tracts, and spinocerebellar tracts; ataxic gait, hyperreflexia, impaired position and vibration sense
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What are modifiable risk factors for stroke?
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CAD Obesity Atrial fibrillation Carotid stenosis Hypercholesterolemia Smoking HTN Diabetes Drug use (cocaine and IV drugs)
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What are nonmodifiable risk factors for stroke?
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FHx of MI or stroke Age > 60 Male Ethnicity (African-American, Hispanic, Asian)
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How are acute ischemic strokes tx?
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tPA is indicated if administered w/in THREE hrs of sx onset, but first rule out contraindication. Be aware of potential bleeding or angioedema. Intra-arterial thrombolysis can be used for select pts w/in 6hrs of major stroke from MCA occlusion if such pts are not suitable candidates for IV tPA Monitor for s/sx of brain swelling, increased ICP and herniation. Serial CTs helpful in the evaluation of deteriorating pts. Can tx w/ mannitol and hyperventilation if necessary. Tx both fever and hyperglycemia since both are assoc w/ worse prognosis
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How are acute hemorrhagic strokes tx?
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ICU admission should be considered, especially for comatose pts or for those who are unable to protect their airways for possible intubation Monitor for s/sx of brain swelling, increased ICP and herniation. Serial CTs helpful in the evaluation of deteriorating pts. Can tx w/ mannitol and hyperventilation if necessary. Tx both fever and hyperglycemia since both are assoc w/ worse prognosis
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What drug is assoc w/ decreased morbidity and mortality in acute ischemic stroke presenting </=48hrs from onset?
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ASA
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What conditions are permitted in stroke pts in order to maintain perfusion of ischemic cerebral tissue?
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permissive hypertension and hypoxemia
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How is severe HTN tx in stroke pts?
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(SBP>220 or DBP>120)/hemorrhagic stroke Tx w/ IV labetalol or nicardipine infusion. In order to admin tPA, SBP must be <185 and DBP <110
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What are common post-stroke complications?
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aspiration pneumonia, UTI, DVT
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What immediate labs should be drawn in tx of acute stroke?
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CBC, platelets, cardiac enzymes, troponins, electrolytes, BUN, Cr, Glu, PTT, PT, INR, lipid profile, O2 sats
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What kind of medications are given to prevent strokes (secondary prevention)?
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ASA, clopidogrel (if stroke is secondary to small vessel diseaes or thrombosis, or if anticoagulation is CI) Anticoagulation: new AF or hypercoagulable states, the target INR is 2-3. In cases involving a prosthetic valve, the target INR is 3-4 or add an antiplatelet agent. Mgmt of HTN, hypercholesterolemia, and diabetes
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What is the single greatest risk for stroke?
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HTN
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What are the causes for SAH?
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trauma berry aneurysms AVM trauma to circle of Willis
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How does SAH present?
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"worst headache of my life" of SAH comes on quickly, in contrast to migraine (peak intensity >30 min) aneurysmal SAH: abrupt-onset, intensely painful "thunderclap" headache, often followed by neck stiffness and other sign sof meningeal irritation, including photophobia, n/v, and meningeal stretch signs. rapid development of obstructive hydrocephalus or seizures often leads to decreased arousal or frank coma and death in the absence of neurosurgical intervention > 1/3 of pts will give a hx of a "sentinel bleed" days to wks earlier marked by an abrupt-onset HA, often w/ n/v, or transient diplopia that completely resolved in a matter of minutes to hours
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What cranial nerve disturbances are assoc w/ berry aneurysms?
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CN III palsy w/ pupillary involvement is assoc w/ berry aneurysms
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What conditions are assoc w/ berry aneurysms that make SAH more likely?
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Marfan's syndrome Aortic coarctation Kidney disease (autosomal dominant, polycystic) Ehler's-Danlos syndrome Sickle cell anemia Atherosclerosis Hx (familial)
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How is SAH dx?
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Head CT w/o contrast: immediate; look for blood in the subarachnoid space. Sensitivity is >95% in those w/ severe SAH but is much lower in pts w/ normal mental status LP: immediate; if CT is neg to look for RBCs, xanthochromia (yellowish CSF due to breakdown of RBCs), increased protein (from the RBCs), and increased ICP Note LP results can be falsely neg in the first 6-12hrs (b/c xanthochromia has not yet developed) and after the first 24-48hrs (because xanthochromia has resolved) Four-vessel angiography: (or equivalent noninvasive angiography such as CT angiography w/ 3D reconstructions) performed once SAH is confirmed. Noninvasive helpful in high-risk cases and in those w/ high clinical suspicion even if CT and LP are unrevealing CALL NEUROSURG
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How is SAH tx?
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Prevent rebleeding (most likely to occur in the first 48hrs). Maintain SBP <150 until the aneurysm is clipped or coiled. Prevent vasospasm and assoc neurologic deterioration (most likely to occur 5-7 days after SAH) by admin CCB, IV fluids, and pressors to maintain BP. Give phenytoin for seizure prophy Decrease ICP by raising the head of the bed and instituting hyperventilation Tx hydrocephalus through a lumbar drain or serial LPs Surgical clipping is the definitive tx for aneurysms. Endovascular coiling is an option for poor surgical candidates
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What are the risk factors of intracerebral hemorrhage?
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HTN, tumor, amyloid angiopathy (in the elderly), anticoagulation, and vascular malformations (AVMs, cavernous hemangiomas)
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How does intracerebral hemorrhage present?
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presents w/ focal motor and sensory deficits that often worsens as the hematoma expands. Severe HA of sudden onset, n/v, seizures, lethargy, or obtundation may also be seen.
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How is intracerebral hemorrhage dx?
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IMMEDIATE noncontrast head CT. Look for mass effect or edema that may predict herniation
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How is intracerebral hemorrhage tx?
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similar to SAH elevate the head of the bed and institute antiseizure prophy Surgical evacuation may be necessary if mass effect is present. Several types of herniation may occur, including central, uncal, subfalcine, and tonsillar
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What is a subdural hematoma?
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occurs following head trauma (usually falls or assaults), leading to rupture of bridging veins and accumulation of blood btw the dura and arachnoid membranes. Common in elderly and alcoholics.
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How does subdural hematoma present?
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HA, changes in mental status, contralateral hemiparesis. Changes may be subacute or chronic. May present as pseudodementia in the elderly
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How is subdural hematoma dx?
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CT: crescent shaped, concave hyperdensity acutely (isodense subacutely, hypodense chronically) that does not cross the midline
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How is subdural hematoma tx?
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surgical evacuation if sx. subdural blood may regress spontaneously if it is chronic
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What are the sites of herniation syndromes?
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1. cingulate herniation under falx cerebri 2. Downward transtentorial (central) herniation 3. Uncal herniation 4. Cerebellar tonsillar herniation into the foramen magnum Coma and death result when these herniations compress the brain stem
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What causes an epidural hematoma?
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usually a result of a lateral skull fracture leading to a tear of the middle meningeal artery.
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How does an epidural hematoma present?
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obvious, severe trauma induces an immediate loss of consciousness followed by lucid interval (min to hrs). uncal herniation leads to coma w/ a "blown pupil" (fixed and dilated ipsilateral pupil) and ultimately ipsilateral hemiparesis
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How is an epidural hematoma dx?
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CT shows lens-shaped, convex hyperdensity limited by the sutures
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How is an epidural hematoma tx?
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emergent neurosurgical evacuation. May quickly evolve to brain herniation and death secondary to the arterial source of bleeding.
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What does a "blown pupil" suggest?
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impending brain stem compression
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How does cingulate herniation present?
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occurs secondary to mass lesions of the frontal lobes. No specific s/sx; frequently seen on head CT
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How does downward transtentorial (central) herniation present?
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occurs when large supratentorial mass lesions push the midbrain inferiorly. presents w/ a rapid change in mental status; bilaterally small and reactive pupils; Cheyne-stokes respirations; and flexor and extensor posturing
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How does uncal herniation present?
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occurs secondary to mass lesions of the middle fossa. CN III becomes entrapped, leading to a fixed and dilated ipsilateral pupil followed by an eye that is deviated "down and out." Ipsilesional hemiparesis ("false localizing") results from compression of the cerebral peduncle (opposite the mass lesion) against the tentorial edge
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How does cerebellar tonsillar herniation into the foramen magnum present?
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occurs secondary to posterior fossa mass lesions. Tonsillar herniation-->medullary compression-->respiratory arrest. usually rapidly fatal.
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What are causes of acute headache?
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new migraine/cluster headache aneurysmal SAH acutely increased ICP (colloid cyst, obstructive hydrocephalus) acute ocular disease (angle-closure glaucoma) cerebral venous thrombosis cavernous sinus thrombosis craniocervical dissection pituitary apoplexy acute severe HTN (pheochromocytoma angina (rare) ischemic stroke/intraparenchymal hemorrhage (headache is usually not the presenting manifestation)
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What are causes of subacute headache?
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new migraine/tension-type headache viral syndrome meningitis cranial infections (acute sinusitis, dental infections, orbital infections, cavernous sinus infections, otitis media/mastoiditis) temporal arteritis subacutely increased ICP (e.g. large tumor, progressive hydrocephalus, altitude sickness, pseudotumor cerebri) subacute ocular disease (keratitis, iritis, scleritis, orbital infxn) subacute severe HTN (e.g. hypertensive encephalopathy, eclampsia) intracranial hypotension (e.g. spontaneous, post-LP) subdural hematoma carbon monoxide lead poisoning in children (rare) encephalitis
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What are causes of chronic/episodeic headache?
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migraine cluster headache tension-type headache medication overuse headaches (e.g. caffeine withdrawal, "rebound" headaches from NSAID or analgesic overuse) trigeminal or other neuralgias (glossopharyngeal, postherpetic) TMJ disease cervical arthritis chronic sinusitis
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What characteristics of a headache should be evaluated in history?
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chronicity intensity location duration diurnal variation triggers provocative factors palliative factors assoc s/sx: Fever, rash, jaw claudication, weight loss, photophobia, nausea, vomiting neurologic sequelae: diplopia, mental status changes, numbness, weakness, dizziness, ataxia, visual disturbances, papilledema, pupillary abnormalities (partial CN III palsy or Horner's syndrome) Pt risk factors: high risk pts >50yo, immunocompromised or w/ preexisting malignancy
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How are headaches dx?
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1) If SAH is suspected, obtain head CT w/o contrast 2) CT is neg, LP is mandatory 3) Obtain a CBC 4) If temporal arteritis is suspected, obtain ESR 5) CT/MRI: for suspected SAH, increased ICP or focal neurologic findings. Use CT w/o contrast to evaluate acute hemorrhage
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What are migraine headaches?
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affects females more often than males; may be familial. Assoc w/ vascular and brain neurotransmitter (serotonin) changes. Pain is ultimately linked to trigeminal nucleus activation in the brain stem. Auras appear to result from a different pathomechanism (electrical spreading depression in the brain, possibly linked to ion channel dysfxn and may occur w/ or w/o the pain of migraine headache. Onset usually occurs by the early 20s.
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What are triggers of migraine headaches?
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foods (red wine), fasting, stress, menses, OCPs, bright light, and disruption in normal sleeping patterns
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How do migraine headaches present?
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throbbing headache (>2hrs but usually <24hrs, and almost always <72hrs in duration) that is assoc w/ n/v, photophobia and noise sensitivity. Usually relieved by sleep and darkness
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How do classic migraines present?
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often unilateral and preceded by a visual aura in the form of either scintillating scotomas (bright or flashing lights) or visual field cuts
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How do common migraines present?
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may be bilateral and periorbital w/o preceding auras
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How are migraines dx?
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based on hx
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How are migraines tx?
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Avoid known triggers Abortive tx: - Triptans (first line after OTC NSAIDs have failed) - metoclopramide - various analgesics - consider sx tx for nausea Prophylaxis tx: - anticonvulsants (gabapentin, topiramate) - TCAs (amitriptyline) - B-blockers (propranolol) - CCBs
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How do cluster headaches present?
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brief, excruciating, unilateral periorbital HA that lasts 30 min to three hrs, during which the pt tends to be extremely restless attacks tend to occur in clusters, affecting the same part of the head at the same time of day (commonly during sleep) and in a certain season of the year Assoc sx: ipsilateral lacrimation of the eye, conjunctival injection. Horner's syndrome and nasal stuffiness
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How are cluster headaches dx?
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classic presentations w/ a hx of repeated attacks over an extended period of time require no evaluation first episodes require a work-up to exclude disorders assoc w/ Horner's syndrome (carotid artery dissection or cavernous sinus infxn)
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How are cluster headaches tx?
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Acute tx: high flow O2, (100% non-rebreather), dihydroergotamine, octreotide, sumatriptan or zolmitriptan Prophy tx: transitional (prednisone, ergotamine), maintenance (verapamil, methysergide, lithium, valproic acid, topiramate)
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How do tension-type headaches present?
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tight, bandlike-pain that is not associated w/ sensory phobia, n/v, or auras and is brought on by fatigue or stress. nonspecific sx (anxiety, poor concentration, difficulty sleeping) may also be seen. May be generalized or most intense in the frontal, occipital, and neck regions. usually occurs at the end of the day.
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How are tension-type headaches dx?
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dx of exclusion r/o giant cell arteritis in pts >50yo w/ new headaches Labs: ESR Exam: often no focal neuro signs
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How are tension-type headaches tx?
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relaxation, massage, hot baths, and avoidance of exacerbating factors NSAIDs and acetaminophen are first-line abortive tx, but triptans may also be considered
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What is likely afflicting this pt? 25yr old male wakes up repeatedly during the night w/ unilateral periorbital pain assoc w/ ipsilateral lacrimation?
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Cluster headache
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What is likely afflicting this pt? 30yo female complains of headaches at the end of the day that worsen w/ stress and improve w/ relaxation or massage?
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tension-type headache
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What is the most common headache dx in adults?
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tension-type headaches
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What causes cavernous sinus thrombosis?
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usually suppurative process of the orbit, nasal sinuses, central face that leads to septic thrombosis of the cavernous sinus nonseptic thrombosis is rare
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What is the most common causative agent of cavernous sinus thrombosis?
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S. aureus other causes: fungi (mucor or aspergillus)
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How does cavernous sinus thrombosis present?
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headache is most common presenting sx orbital pain, edema, diplopia (2ndary to oculomotor abducens, or trochlear nerve involvement), or visual disturbances and may describe recent history of sinusitis or facial infxn Exam: typically appear ill and have a FEVER red eye, proptosis, ptosis, opthalmoplegia of the affected eye (partial or complete). Diminished pupillary constriction (CNIII) and/or dilation (Horner's) may also be present Changes in mental status such as confusion, drowsiness, or coma suggests spread to CNS or sepsis Late findings: meningismus or systemic signs of sepsis
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How is cavernous sinus thrombosis dx?
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Labs: increased WBC Blood cultures: causative agent CSF: increased protein consistent w/ parameningeal rxn MRI: principal means of confirming anatomic dx. MR or CT venography may be impt adjuncts Bx of paranasal sinuses or other affected tissues is often necessary in fungal cases for organism ID by histology and culture
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How is cavernous sinus thrombosis tx?
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Aggressive and empiric Abx tx: penicillinase-resistant penicillin (nafcillin or oxacillin) plus a third- or fourth-gen cephalosporin (ceftriaxone or cefepime) to provide broad-spectrum coverage pending blood culture results Potential anaerobic infxn from sinus or dental sources should be covered w/ flagyl Vancomycin can be added to address potential MRSA involvement Antifungal tx is required for fungal cases IV abx for 3-4 wks
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What are seizure disorders?
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Paroxsymal events assoc w/ aberrant electrical activity in the brain detectable by EEG, leading to changes in neurologic perception or behavior
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Can seizures present w/ aura?
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50-60% present w/ aura
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What characteristics of seizures must be elucidated via history?
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epilepsy? unprovoked? recurrent? how often? self-limited? underlying conditions drugs behavior after seizure (post-ictal phase) loss of consciousness? seizures ever witnessed? incontinence, loss of bowel control?
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What is often elevated w/ an epileptic seizure?
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serum prolactin elevated during seizures and in the immediate postictal period
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What are causes of infantile seizures?
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perinatal injury infxn metabolic congenital
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What are causes of childhood seizures (2-10yrs)?
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idiopathic infxn trauma febrile
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What are causes of adolescent seizures?
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idiopathic trauma drug withdrawal AVM
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What are causes of adult (18-35yrs) seizures?
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trauma alcoholism brain tumor
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What are causes of adults (35+yrs) seizures?
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trauma stroke metabolic disorders alcoholism brain tumor
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What are some non neurologic etiologies of seizures?
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hypoglycemia hyponatremia hypocalcemia hyperosmolar states hepatic encephalopathy uremia porphyria drug overdose (cocaine, antidepressants, neuroleptics, methylxantines, lidocaine) drug withdrawal (alcohol and other sedatives) eclampsia hyperthermia hypertensive encephalopathy head trauma cerebral hypoperfusion
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What do focal seizures suggest?
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focal CNS pathology may be the presenting sign of a tumor, stroke, AVM, infxn, hemorrhage, or developmental abnormality
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What are partial seizures?
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arise from a discrete region, or an "epileptogenic focus" in one cerebral hemisphere and do not lead to loss of consciousness unless they secondarily generalize
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How do simple partial seizures present?
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may include motor features (e.g. jacksonian march, progressive jerking of successive body regions) as well as sensory, autonomic, or psychic features (fear, deja vu, hallucinations) w/o alteration of consciousness. a postictal focal neurologic deficit (hemiplegia/hemiparesis, or Todd's paralysis) is possible and usually resolves w/in 24hrs. Often confused w/ acute stroke (ruled out by MRI)
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How do complex partial seizures present?
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typically involve the temporal lobe (70-80%) w/ bilateral spread of the aberrant electrical discharge. Characterized by an impaired level of consciousness, auditory or visual hallucinations, deja vu, automatisms (lip smacking, chewing, or even walking), and postictal confusion/disorientation and amnesia.
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How are partial seizures dx?
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Obtain EEG R/o systemic causes w/ CBC, electrolytes, calcium, fasting glucose, LFTs, a renal panel, RPR, ESR, and a toxicology screen Imaging if suspect focal brain lesion. (CT/MRI)
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How are partial seizures tx?
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Tx underlying cause Recurrent partial seizures: Phenytoin, oxcarbazepine, carbamazepine (Tegretol), phenobarbitol, and valproic acid can be admin as monotherapy. In children, phenobarbitol is first-line anticonvulsant Intractable temporal lobe seizures: consider anterior temporal lobectomy
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What is the most likely condition afflicting this pt? Pt presents w/ progressive jerking of successive body regions and hallucinations, but w/o loss of consciousness.
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simple partial seizures
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What is the most likely condition afflicting this pt? Pt presents w/ an episode of lip smacking assoc w/ an impaired level of consciousness and followed by confusion.
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complex partial seizures
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How do tonic-clonic seizures present?
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primarily idiopathic. Partial seizures can evolve into this. Presents w/ sudden onset of loss of consciousness w/ tonic extension of the back and extremities, continuing w/ 1-2 min of repetitive, symmetric clonic movts. marked by incontinence and tongue biting. pts may appear cyanotic during the ictal period. consciousness is slowly regained in the postictal period, but pts are confused and may prefer to sleep; muscle aches and headaches may be present.
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How are tonic-clonic seizures dx?
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EEG typically shows 10Hz activity during the tonic phase and slow waves during the clonic phase
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How are tonic-clonic seizures tx?
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protect the airway treat the underlying cause if known primary generalized tonic-clonic seizures: Phenytoin, fosphenytoin, or valproate (1st line tx). Lamotrigine or topiramate may be used as adjunctive tx secondarily generalized tonic-clonic seizures: tx is the same as that if for partial seizures
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What is the most likely condition afflicting this pt? Pt presents w/ chronic movts assoc w/ loss of consciousness and incontinence
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tonic clonic seizures
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How do absence seizures present?
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begin in childhood and subside before adulthood. often familial present w/ brief (5-10 sec), often unnoticeable episodes of impaired consciousness occurring up to hundreds of times per day. Pts are amnestic during and immediately after seizures and may appear to be daydreaming or staring. Eye fluttering or lip smacking is common
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How are absence seizures dx?
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EEG shows classic three-per second spike and wave discharges.
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How are absence seizures tx?
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ethuosuximide is the first line agent
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What is status epilepticus?
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medical emergency consisting of prolonged (>10min) or repetitive seizures that occur w/o a return to baseline consciousness. May be either convulsive (more medically urgent form) or nonconvulsive
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What are common causes of status epilepticus?
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anticonvulsant withdrawal/noncompliance, anoxic brain injury, EToH/sedative withdrawal or other drug intoxication, metabolic disturbances (hyponatremia), head trauma, and infection death usually results from the underlying medical condition and may occur in 10% of cases of status epilepticus
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How is status epilepticus dx?
answer
determine the underlying cause w/ pulse oximetry, CBC, electrolytes, calclium, glu, ABGs. LFTs, BUN/Cr, ESR, antiepileptic drug levels, and a toxicology screen Obtain EEG and brain imaging, but defer testing until the pt is stabilized Obtain a stat head CT to evaluate for intracranial hemorrhage Obtain LP in the setting of fever or meningeal signs, but only after having done CT scan to assess the safety of LP
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How is status epilepticus tx?
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Maintain ABCs; consider rapid intubation for airway protection Admin: thiamine, glu, and naloxone to presumptively tx potential etiologies Give IV benzodiazepine (lorazepam or diazepam) plus a loading dose of fosphenytoin If seizures continue, intubate and load w/ phenobarbital. Consider an IV sedative (midazolam or pentobarbital) and initiate continuous EEG monitoring Initiate meticulous search for underlying cause
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What is the most likely condition afflicting this pt? Child is brought from school to her pediatrician after experiencing five-second episodes of staring into space.
answer
absence (petit mal) seizures
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What are infantile spasms?
answer
form of generalized epilepsy that typically begins w/in six months of birth. May be idiopathic or secondary to a variety of conditions, including PKU, perinatal infxns, hypoxic-ischemic injury and tuberous sclerosis affects males more often than females; assoc w/ a + FHx
question
How do infantile spasms present?
answer
presents w/ tonic, bilateral, symmetric jerks of teh head, trunk and extremities that tend to occur in clusters of 5-10; arrest of psychomotor development occurs at the age of seizure onset. The majority of pts have mental retardation
question
How are infantile spasms dx?
answer
look for an abnormal interictal EEG characterized by hypsarrhythmia
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How are infantile spasms tx?
answer
hormonal tx w/ ACTH, prednisone, and clonazepam or valproic acid. Meds may tx the spasms but have little impact on pt's long term prognosis.
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What is the most likely condition afflicting this pt? Male infant is brought to the hospital w/ muscular jerks and an uncle who had the same problem.
answer
infantile spasms aka West Syndrome
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What is BPPV?
answer
common cause of recurrent peripheral vertigo resulting from a dislodged otolith that leads to disturbances in the semicircular canals (95% posterior, 5% horizontal)
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How does BPPV present?
answer
pts w/ posterior BPPV present w/ transient, episodic vertigo (lasting <1 min) and mixed upbeat-torsional nystagmus triggered by changes in head position (classically while turning in bed, gettingin/out of bed, reaching overhead. Some pts complain of nonvertiginous feelings of dizziness or lightheadedness. N/V are uncommon owing to short-lived stimulus
question
How is BPPV dx?
answer
Dix-Hallpike maneuver: have the pt turn his or her head 45 degrees right or left and go from a sitting to a supine position while quickly turning the head to the side If vertigo and typical nystagmus (upbeat and toward the affected shoulder) are reproduced, BPPV is the likely dx Nystagmus that persists for >1 min, gait disturbance, or n/v that is out of proportion to nystagmus should raise concern for a central lesion
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How is BPPV tx?
answer
some 80% of cases can be resolved at the bedside using the modified Epley maneuver (a 270 degree head rotation from the Dix-Hallpike testing position). the condition usually subsides spontaneously in wks to months but often recurs months or years later. Antivertigo meds: meclizine, are generally CI as they tend to inhibit central compensation, which may lead to chronic, unsteadiness and falls in the elderly.
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How does acute peripheral vestibulopathy (labryinthitis and vestibular neuritis) present?
answer
acute onset of severe vertigo, head-motion intolerance, and gait unsteadiness accompanied by nausea, vomiting, and nystagmus Auditory or aural sx (labyrinthitis) may include unilateral tinnitus, ear fullness, or hearing loss without auditory or aural sx (more common), the condition is known as "vestibular neuritis"
question
How is acute peripheral vestibulopathy dx?
answer
Dx of exclusion (worry about r/o cerebellar stroke) Exam findings: - abnormal vestibulo-ocular reflex (VOR) as determined by a bedside head impulse test (i.e. rapid head rotation from lateral to center while staring at the examiner's nose) - predominantly horizontal nystagmus that always beats in one direction, opposite the lesion - no vertical eye misalignment by alternate cover testing High risk pts-->MRI ASAP - atypical eye findings or any neurologic sx or signs - cannot stand independently - have head or neck pain - >50yo - have one or more stroke risk factors Low risk pts--> caloric testing
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What other conditions mimic labyrinthitis?
answer
(w/ auditory sx) - lateral pontine/cerebellar stroke (AICA arterial territory)
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What other conditions mimic vestibular neuritis?
answer
(w/o auditory sx) - lateral medullary/cerebellar stroke (PICA arterial territory)
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How is acute peripheral vestibulopathy tx?
answer
acute tx consists of corticosteroids given <72hrs after sx onset and vestibular sedatives (e.g. meclizine). condition usually subsides spontaneously w/in weeks to months. once the hyperacute stage has passed, cautious engagement in normal physical activities and exercise should be encouraged
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What condition is this pt afflicted by? 27yo male presents w/ vertigo and vomiting for one week after having been diagnosed w/ a viral infxn.
answer
acute vestibular neuritis
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What is Meniere's disease?
answer
cause of recurrent vertigo w/ auditory sx that affects at least 1 in 500 in the US. More common in women
question
How does Meniere's disease present?
answer
presents w/ recurrent episodes of severe vertigo, hearing loss, tinnitus, or ear fullness, often lasting hours to days. N/V are typical. Pts progressively lose low-frequency hearing over years and may become deaf on the affected side.
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How is Meniere's disease dx?
answer
Clinical dx Two episodes (lasting 20min or more) w/ remission of sx between episodes, hearing loss documented at least once w/ audiometry, and tinnitus, or aural fullness are needed to make the dx R/o TIA, otosyphilis MRI w/ vascular imaging to r/o other cerebrovascular disease
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How is Meniere's disease tx?
answer
1st line: Low-sodium diet and diuretic tx 2nd line: migraine diets, other lifestyle changes, prophylactic antimigraine meds, benzos or antiemetics Severe unilateral cases: ablative tx (intratympanic gentamicin to damage the labyrinth, vestibular nerve section) used w/ some success.
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What are vestibular migraines?
answer
recurrent cause of vertigo (usually w/o auditory sx) that affects roughly 10% of migraine sufferers. Its pathogenesis may be related to intermittent electrical (ion channel) dysfxn in the cerebellum
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How does vestibular migraines present?
answer
recurrent episodes of mild dizziness to severe vertigo lasting minutes to days. Assoc sx: n/v, photophobia, headaches variably present and may be mild or severe No deficits btw spells, but balance may deteriorate over decades
question
How is vestibular migraines dx?
answer
dx made clinically Dx would otherwise qualify for a dx of Meniere's save the absence of auditory sx and documented hearing loss are likely to have vestibular migraine Hx of photo-phonophobia during the episode, particularly if dizziness is assoc w/ headache, is highly suggestive in pts Dx is one of exclusion - care should be taken to ensure that pts do not have intermittent dizziness due to TIA. In pts 72hrs) should raise concern for vertebral artery dissection w/ TIAs. Brain MRI w/ vascular imaging to assess potential intracranial pathology, particularly cerebrovascular disease R/O episodic ataxia type 2 can be corroborated by genetic testing
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How are vestibular migraines tx?
answer
Prevention: migraine meds, diet, lifestyle changes Second line: benzos, antiemetics NO surgery
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What is syncope?
answer
most common causes of loss of consciousness secondary to an abrupt drop in cerebral perfusion. Often confused w/ seizures.
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What are the causes of syncope?
answer
cardiac arrhythmias and cardiac outflow obstruction, vasovagal syncope, orthostatic hypotension, micturition-related syncope, basilar TIAs, and idiopathic causes
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What is presyncope?
answer
described as a feeling of imminent loss of consciousness w/o actual fainting.
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How does syncope present?
answer
Trigger: standing for long period of time, fear/sight of blood, Valsalva maneuver Prodrome: lightheadedness or dizziness, muffled sounds, constricting vision, diffuse weakness, diaphoresis, or pallor. Leads to loss of consciousness and muscle tone for <30sec and recovery w/in seconds
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How is Meniere's different from BPPV?
answer
Meniere's consists of recurrent episodes that last hours to days
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How is Meniere's different from vestibular migraine?
answer
vestibular migraine usually has no associated auditory or aural sx
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How is syncope dx?
answer
Structural CNS causes (e.g. basilar, TIA, intermittent obstructive hydrocephalus) are rare among pts who return to normal mental status and have a normal neuro exam after a brief loss of consciousness R/O seizures Unless there is a clear vasovagal faint in a young pt w/o cardiac disease or risk factors, place all pts on telemetry or Holter monitoring to evaluate for arrhythmia, and r/o MI w/ an EKG and cardiac enzymes Get an EEG to r/o seizures Consider echo, tilt-table test, or neuroimaging, especially vascular
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How is syncope tx?
answer
treat underlying disease; avoid triggers
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What is myasthenia gravis?
answer
autoimmune disorder caused by antibodies that bind to postsynaptic acetylcholine (ACh) receptors located at the neuromuscular jxn Assoc w/ thyrotoxicosis, thymoma, and other autoimmune disorders
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How does myasthenia gravis present?
answer
fluctuating fatigable ptosis or double vision, bulbar sx (dysarthria, dysphagia), and proximal muscle weakness. Sx usually worsen as the day progresses but fluctuate dramatically Pts report: difficulty climbing stairs, rising from a chair, brushing their hair, swallowing
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What is a myasthenic crisis?
answer
rare but includes the potentially lethal complications of respiratory compromise and aspiration
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How is MG dx?
answer
Edrophonium (tensilon test): anticholinesterase leads to rapid amelioration of sx. rarely used today owing to risk of bradycardia Ice test: place a pack of ice on one eye for five min; ptosis resolves transiently EMG: abnormal single-fiber EMG and/or decremental response to repetitive nerve stimulation can yield additional confirmation Labs: + ACh abs in 80% of pts; anti-muscle-specific kinase (anti-MuSK) abs are + in 5% Imaging: Chest CT to evaluate for thymoma. 85% of pts w/ thymoma have + abs against striated muscle Follow serial FVCs to determine the need to intubate
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How is MG tx?
answer
Anticholinesterases (pyridostigmine) are used for sx tx Prednisone and other immunosuppressants (e.g. azathioprine, cyclosporine, mycophenolate) are the mainstays of tx Severe cases: plasmapheresis or IVIG may provide temporary relief (days to weeks) Resection of thymoma can be curative Avoid giving certain Abx (aminoglycosides) and drugs (B-blockers) to pts w/ MG
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What is Lambert-Eaton Myasthenic Syndrome?
answer
autoimmune disorder caused by abs directed toward presynaptic calcium channels in the neuromuscular jxn
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What is a significant risk factor for Lambert-Eaton Myasthenic Syndrome?
answer
small cell lung carcinoma
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How does Lambert-Eaton Myasthenic Syndrome present?
answer
weakness and fatigability of proximal muscles along w/ depressed or absent DTRs. Extraocular, respiratory, and bulbar muscles are typically spared
question
How is Lambert-Eaton Myasthenic Syndrome dx?
answer
repetitive nerve stimulation reveals a characteristic incremental response. Dx by autoabs to presynaptic calcium channels Chest CT indicative of lung neoplasm
question
How is Lambert-Eaton Myasthenic Syndrome tx?
answer
Tx small cell lung cancer Tumor resection may reverse symptoms 3, 4-diaminopyridine or guanidine can be given; acetylcholinesterase inhibitors (pyridostigmine) can be added to any regimen Corticosteroids and azathioprine can be combined or used alone for immunosuppression
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What are possible etiologies of MS?
answer
unclear etiologies - autoimmune etiology in genetically susceptible who are exposed to environmental triggers such as viral infxns - T-cell mediated
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What are the subtypes of MS?
answer
- relapse-remitting - primary progressive - secondary progressive - progressive relapsing
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How does MS present?
answer
multiple neurologic complaints that are separated in time and space and are not explained by a single lesion. As disease progresses, permanent deficits may accumulate Limb weakness, optic neuritis, paresthesias, diplopia, vertigo, nystagmus, gait unsteadiness, urinary retention, sexual and bowel dysfxn, depression, and cognitive impairment are also seen. Sx classically worsen transiently w/ hot showers
question
Which subtype has the best prognosis?
answer
relapse-remitting
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What is Lhermitte's sign and what does that suggest?
answer
sharp pain traveling up or down the neck and back w/ flexion, generally suggests the presence of cervical myelitis
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How are the responses to repetitive nerve stimulation different between Lambert-Eaton and MG?
answer
Lambert-Eaton: characteristic incremental response MG: decremental response
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What is the classic triad of MS?
answer
scanning speech intranuclear ophthalmoplegia nystagmus
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How does pregnancy affect MS?
answer
pregnancy is assoc w/ a decrease in sx
question
How is MS dx?
answer
MRI: multiple, ASx, often periventricular white matter lesions (Dawson's fingers), esp in the corpus callosum. Active lesions enhance w/ gadolinium CSF: reveals mononuclear pleocytosis (>5 cells/uL), an increased IgG index, or oligoclonal bands (nonspecific) Abnormal somatosensory or visual evoked potentials may also be present
question
How is MS tx?
answer
Corticosteroids should be given during acute exacerbations Immunomodulators alter relapse rates in relapsing-remitting MS and include interferon-B (1a) (Avonex/Rebif), interferon-B (1b) (Betaseron), and copolymer-1 (Copaxone) Worsening relapsing/remitting or progressive MS: Mitoxantrone Alternative tx: cyclophosphamide, IVIG, plasmapheresis Sx Tx: crucial. includes baclofen for spasticity; cholinergics for urinary retention; anticholinergics for urinary incontinence; carbamazepine or amitriptyline for painful paresthesias; and antidepressants for clinical depression
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What is Guillain-Barre Syndrome?
answer
acute, rapidly progressive, acquired demyelinating autoimmune disorder of the peripheral nerves that results in weakness. AKA acute inflammatory demyelinating polyneuropathy
question
What kind of infxns is GBS assoc w/?
answer
campylobacter jejuni infxn viral infxn influenza vaccine
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How does GBS present?
answer
progressive (over days) symmetric, ascending paralysis (distal to proximal) involving the truck, diaphragm and cranial nerves atypical presentations common Autonomic dysregulation occurs: areflexia, dysesthesias may be present
question
How is GBS dx?
answer
evidence of diffuse demyelination on EMG and nerve conduction studies, which show decreased nerve conduction velocity CSF protein level > 55mg/dL w/ little or no pleocytosis (albuminocytologic dissociation)
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How is GBS tx?
answer
Admit to ICU for impending respiratory failure Plasmapheresis and IVIG are first-line tx. Corticosteroids are not indicated Aggressive physical rehabilitation is imperative.
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What are the 5As of GBS?
answer
acute inflammatory demyelinating polyradiculopathy ascending paralysis autonomic neuropathy arrhythmias albuminocytologic dissociation
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What is ALS?
answer
chronic, progressive degenerative disease of unknown etiology characterized by loss of upper and lower motor neurons unrelenting course and almost always progresses to respiratory failure and death, usually w/in five years of dx onset ages 40-80
question
How does ALS present?
answer
Asymmetric, slowly progressive weakness (over months to yrs) affecting the arms, legs, diaphragm, and lower cranial nerves. Some pts initially present w/ fasciculations. Weight loss is common. UMN and LMN signs. Eye movts and anal sphincter tone generally spared. Tongue atrophy and fasciculation may be apparent Emotional lability
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What condition is afflicting this pt? 55yo male presents w/ slowly progressive weakness in his upper extremity and later his right, assoc w/ fasciculations but w/o bladder disturbance and w/ a normal cervical MRI
answer
ALS
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How is ALS dx?
answer
Clinical presentation Signs: involvement of the tongue (CN XII) or oropharyngeal muscles (CN IX, X), "bulbar" involvement, pathology above the foramen magnum and generally excludes the most common differential, cervical spondylosis w/ compressive myelopathy, as a cause EMG/nerve conduction studies: reveal widespread denervation and fibrillation potentials. Such studies are principally performed to exclude other demyelinating motor neuropathies Imaging: CT/MRI: cervical spine is done to exclude structural lesions, particularly in those w/o bulbar involvement
question
How is ALS tx?
answer
supportive measures and pt education
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What are the 5A's of dementia?
answer
aphasia amnesia agnosia apraxia disturbances in abstract thought
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What is the differential dx for dementia?
answer
DEMENTIAS NeuroDegenerative diseases Endocrine Metabolic Exogenous Neoplasm Trauma Infection Affective disorders Stroke/Structural
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What is dementia?
answer
chronic, progressive, global decline in multiple cognitive areas Alzheimer's disease accounts for 60-80% of cases
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What are the risk factors for Alzheimer's disease?
answer
age female gender family hx Down Syndrome low educational status
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What is the characteristic pathology of Alzheimer's disease?
answer
neurofibrillary tangles, neuritic plaques w/ amyloid deposition, amyloid angiopathy, and neuronal loss
question
How does Alzheimer's disease present?
answer
amnesia for newly acquired info (1st presenting sx), then language deficits, acalculia, depression, agitation, psychosis, apraxia (inability to perform skilled movts) mild cognitive impairment may precede AD 10yrs. Survival is 5-10yrs from onset of sx, w/ death usually occurring secondary to aspiration pneumonia or other infxns. Physical exam usually normal
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How is AD dx?
answer
Dx of exclusion; definitive by autopsy only Clinical: suggested clinical features and by insidiously progressive cognitive course w/o substantial motor impairment Imaging: (CT/MRI) see atrophy, r/o other causes (vascular demential, NPH, chronic subdural hematoma) (PET) nonspecific bilateral temporoparietal hypometabolism CSF: normal Neuropsych testing: help distinguishing dementia from depression. Hypothyroidism, vitamin B12 deficiency, neurosyphilis should be r/o in atypical cases
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How is AD tx?
answer
Prevention of assoc sx: - provide supportive tx for pt and family - tx depression, agitation, sleep disorders, hallucinations, delusions Prevention of disease progression: - Cholinesterase inhibitors (donepezil, rivastigmine, galantamine, tacrine)-- first line - Memantine (NMDA receptor antagonist), slows decline in moderate to severe disease
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What is vascular dementia?
answer
dementia assoc w/ hx of stroke and cerebrovascular disease is the second most common type of dementia
question
What are the risk factors for vascular dementia?
answer
age HTN diabetes embolic sources hx of stroke
question
How is vascular dementia dx?
answer
Criteria for dx of vascular dementia include the presence of dementia and two or more of the following: - focal neurologic signs on exam - sx onset that was abrupt, stepwise, or related to stroke - brain imaging showing evidence of old infarctions or extensive deep white matter changes secondary to chronic ischemia
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How is vascular dementia tx?
answer
same prevention and tx protocols as stroke
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What condition is afflicting this pt? abrupt changes in mental status over time rather than a steady decline
answer
vascular dementia
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What is frontotemporal dementia (Pick's disease)?
answer
rare, progressive form of dementia characterized by atrophy of the frontal and temporal lobes. Round intraneuronal inclusions known as Pick bodies are the classic pathologic finding
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How does frontotemporal dementia present?
answer
significant changes in behavior and personality early in the disease other sx: speech disturbance, inattentiveness, occasionally extrapyramidal signs rare begins after age 75
question
How is frontotemporal dementia dx?
answer
suggested by clinical features and by evidence of circumscribed frontotemporal atrophy revealed by MRI or CT
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How is frontotemporal dementia tx?
answer
tx symptomatic only no curative tx
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What is NPH?
answer
potentially treatable form of dementia that is thought to arise from impaired CSF outflow from the brain
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How does NPH present?
answer
Classic triad: - dementia - gait apraxia - urinary incontinence Headaches and other signs of increased ICP (e.g. papilledema) typically do not appear, although continuous ICP monitoring may reveal spikes of elevated pressure
question
How is NPH dx?
answer
Clinical: gait is classically "magnetic" or with "feet glued to the floor" as the forefoot is not completely dorsally extended LP or continuous lumbar CSF drainage for several days, reveals normal pressure but may cause clinically significant improvement of the pt's sx Imaging: CT/MRI shows ventricular enlargement out of proportion to sulcal atrophy
question
How is NPH tx?
answer
surgical CSF shunting
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What is CJD?
answer
most common prion disease, but an extremely rare form of dementia CJD: member of transmissible spongiform encephalopathies, all characterized by spongy degeneration, neuronal loss, and astrocytic proliferation abnormal protease resistant prion protein accumulates in the brain
question
How does CJD present?
answer
subacute dementia w/ ataxia or myoclonic jerks w/ rapid clinical decline that is noted weeks to months after sx onset
question
How is CJD dx?
answer
suggested by clinical features EEG: pyramidal signs and periodic sharp waves MRI w/ diffusion-weighted imaging may show increased T2 and FLAIR intensity in the putamen and the head of the caudate and is also used to exclude structural brain lesions CSF: Normal definitive dx: brain bx or autopsy. Specimen handled w/ caution to avoid transmission
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What is the DDx for CJD?
answer
viral encephalitis Hashimoto's (steroid responsive) encephalopathy toxic encephalopathy (lithium, bismuth)
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How is CJD tx?
answer
no effective tx Most pts die w/in a year of onset
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What is Huntington's disease?
answer
rare, hyperkinetic, autosomal dominant disease involving multiple abnormal CAG triplet repeats (<29 is normal) w/in the HD gene on chromosome 4
question
What is anticipation?
answer
earlier and more severe expression of disease in subsequent generations
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How does Huntington's disease present?
answer
30-50yo gradual onset chorea, altered behavior, dementia - chorea= sudden onset of purposeless, involuntary dancelike movts - dementia = irritability, clumsiness, fidgetiness, moodiness, and antisocial behavior Weight loss and depression
question
How is Huntington's disease dx?
answer
clinical dx confirmed by genetic testing Imaging (CT/MRI): cerebral atrophy (caudate and putamen) Molecular genetic testing to determine the number of CAG repeats
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How is Huntington's disease tx?
answer
There is no cure, disease progression cannot be halted. Tx sx - reserpine or tetrabenazine to minimize unwanted movements - psychosis: atypical antipsychotics to reduce the risk of extrapyramidal side effects or tardive dyskinesia - depression: SSRIs Genetic counseling to offspring
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What condition afflicts this pt? 43yo male presents w/ sudden onset of chorea, irritability, and antisocial behavior and his father experienced these sx at a slightly older age
answer
Huntington's disease
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What is Parkinson's disease?
answer
idiopathic hypokinetic disorder that usually begins after age 50-60 and is attributable to dopamine depletion in the substantia nigra. Characterized by Lewy bodies, which are intraneuronal eosinophilic inclusions
question
How does PD present?
answer
Parkinson's Tetrad - resting tremor (pill rolling) - rigidity (cogwheeling) - bradykinesia - postural instability (stooped posture, impaired righting reflexes, freezing, falls) Other features: masked facies, memory loss, micrographia
question
What are nonidiopathic causes of parkinsonism?
answer
viral encephalitis (postencephalitic parkinsonism) trauma (dementia pugilistica) numerous toxins (manganese, MPTP, and iatrogenic, neuroleptics (tardive dyskinesia)
question
How are nonidiopathic causes of parkinsonism often dx?
answer
unresponsiveness to levodopa/carbidopa
question
What other idiopathic dementias mimic PD?
answer
progressive supranuclear palsy multiple system atrophy
question
What is the difference between gait in NPH and PD?
answer
preservation of arm swing in NPH
question
How is PD tx?
answer
Levodopa and carbidopa Dopamine agonists (ropinirole, pramipexole, bromocriptine) - used to tx early disease - apomorphine is another dopamine agonist that can be used for rescued thearpy if sudden additional dose is needed Seleginline (MAO-B inhibitor): neuroprotective and may decrease and may decrease need for levodopa COMT inhibitors (entacapone or tolcapone) are not given alone but increase the availability of levodopa and decrease motor fluctuations Amantidine: mild antiparkinson's activity. improves akinesia, rigidity, and tremor. if med tx fails: surgical pallidotomy or chronic deep brain stimulation to produce clinical benefit
question
What are more common, metastatic brain neoplasms or primary?
answer
metastatic (70%)
question
What is a SE of pramipexole?
answer
uncontrolled gambling
question
What are the most common neoplasms that metastasize to the brain?
answer
lung, breast, kidney, GI tract, neoplasms, and melanoma Often occur at the gray-white jxn; may be multiple discrete nodules; characterized by rapid growth, invasiveness, necrosis, and neovascularization
question
What are the most common primary CNS tumors in adults?
answer
glioblastoma multiforme and meningioma
question
What are the most common primary CNS tumors in children?
answer
medulloblastomas and astrocytomas
question
How do brain neoplasms present?
answer
Sx depend on tumor type and location (local growth) can cause: - resulting mass effect - cerebral edema - elevated ICP secondary to ventricular obstruction Common sx: headaches, seizures, slowly progressive focal motor deficits Hemispheric tumors: visual field abnormalities, neuropsych sx (personality changes, lethargy, syncope, cognitive decline, aphasia, apraxia, depression Parasellar lesions: visual loss and/or diplopia Posterior fossa lesions: gait ataxia, cranial nerve deficits and/or increased ICP from obstructive hydrocephalus Metastasis: intracranial hemorrhage (RCC, thyroid cancer, choriocarcinoma, melanoma)
question
What are sx of increased ICP?
answer
headache (worse in the AM or w/ recumbency) N/V diplopia
question
Where are most adult primary brain tumors?
answer
2/3 are supratentorial
question
Where are most child primary brain tumors?
answer
2/3 are infratentorial
question
How are brain neoplasms dx?
answer
Imaging: Contrast CT and MRI w/ and w/o gadolinium to localize and determine the extent of the lesion (gadolinium MRI better for visualizing soft tissue tumors and vascularity; CT better for skull base lesions and emergencies) Histologic dx via CT guided biopsy or surgical tumor debulking/removal
question
How are brain neoplasms tx?
answer
Resection (if possible), radiation, chemotx Corticosteroids can be used to decrease vasogenic edema and decrease ICP. Mgmt is palliative Seizure prophy to be used in pts who have had seizure
question
What is an astrocytoma and how does it present?
answer
arises in brain parenchyma. Low grade astrocytomas are relatively uncommon. Presents w/ seizures, focal deficits, or headache. has a protracted course. Has a better prognosis than glioblastoma multiforme
question
How is astrocytoma tx?
answer
resection if possible, radiation
question
What is glioblastoma multiforme (grand IV astrocytoma) and how does it present?
answer
high mitotic activity and either endothelial proliferation or necrosis in tumor, leading to ring-enhancing lesions on MRI. There is a major difference btw grade III and grade IV most common primary brain tumor. presents w/ headache and increase seizures, focal deficits, or headache. progresses rapidly and has a poor prognosis (<1yr from the time of prognosis)
question
How is glioblastoma multiforme tx?
answer
surgical removal/resection. Radiation and chemotx have variable results
question
What is meningioma and how does it present?
answer
originates from the dura mater or arachnoid. presentation is dependent on location; often related to cranial neuropathy or is an incidental finding. Good prognosis. Incidence increases w/ age. Imaging may reveal dural tail.
question
How is meningioma tx?
answer
surgical resection; radiation for unresectable tumors
question
What is an acoustic neuroma (Schwannoma) and how does it present?
answer
derived from Schwann cells presents w/ ipsilateral tinnitus, hearing loss, vertigo, and late signs of CN V-VII or brain stem compression
question
How are acoustic neuromas tx?
answer
surgical removal
question
What is a medulloblastoma and how does it present?
answer
primitive neuroectodermal tumor that arises from the fourth ventricle and causes increased ICP common in children. highly malignant; may seed the subarachnoid space. May cause obstructive hydrocephalus
question
How is medulloblastoma tx?
answer
surgical resection coupled w/ radiation and chemotx
question
What is an ependymoma and how does it present?
answer
arises from ependyma of the ventricle (commonly the fourth) or the spinal cord common in children; low grade may cause obstructive hydrocephalus
question
How is ependymoma tx?
answer
surgical resection; radiation
question
What is neurofibromatosis?
answer
most common neurocutaneous disorder 2 types: NF1 and NF2 Autosomal dominant inheritance NF genes located on chromosome 17 and 22
question
How does NF present?
answer
NF1 Criteria (2 or more of the following): - six cafe au lait spots (each >/= 5 mm in children or >/= 15mm in adults) - 2 neurofibromas of any type - freckling in the axillary or inguinal area - optic glioma - two Lisch nodules (pigmented iris harmatomas) - bone abnormality (e.g. kyphoscholiosis) - first degree relative w/ NF1 NF2 Criteria: - bilateral acoustic neuromas OR first degree relative w/ NF2 and either unilateral acoustic neuromas or two of any of the following: neurofibromas, meningiomas, gliomas, schwannoma - other features: seizures, skin nodules, cafe au lait spots
question
How is NF dx?
answer
MRI of brain, brain stem, and spine w/ gadolinium Derm exam Opthy exam FHx auditory testing recommended
question
How is NF tx?
answer
no cure; tx sx (surgery for kyphoscoliosis, debulking of tumors) acoustic neuromas and optic gliomas can be treated w/ surgery or radiosurgery. Meningiomas may be resected
question
What is tuberous sclerosis?
answer
autosomal dominant inheritance affects many organ systems: CNS, skin, heart, retina, kidneys
question
How does tuberous sclerosis present?
answer
convulsive seizures (infantile spasms in infants) "ash-leaf" hypopigmented lesions on the trunk and extremities mental retardation (increased likelihood w/ early age of onset) sebaceous adenomas (small red nodules on the nose and cheeks in the shape of a butterfly) and a shagreen patch (rough papule in the lumbosacral region w/ an orange-peel consistency two retinal lesions: 1) mulberry tumors, which arise from the nerve head and 2) phakomas, round, flat, gray lesions located peripherally in the retina Sx are secondary to small benign tumors that grow on the face, eyes, brain, kidney, and other organs MR and CHF from cardiac rhabdomyoma Renal involvement to include harmatomas, angiomyolipomas, or rarely, renal cell carcinoma
question
What condition is this pt afflicted by? Infantile spasms in the setting of a hypopigmented lesion on the child's trunk?
answer
tuberous sclerosis
question
How is tuberous sclerosis dx?
answer
Clinical dx Skin lesions enhanced via Wood's UV lamp Imaging: - Head CT: reveals calcified tubers w/in the cerebrum in the periventricular area. Lesions may on rare occasion transform into malignant astrocytomas - EKG: evaluate for rhabdomyoma of the heart, masses, polycystic disease - Renal CT: show angiomyolipomas (cystic of fibrous pulmonary changes) - CXR: pulmonary lesions or cardiomegaly secondary to rhabdomyoma
question
How is tuberous sclerosis tx?
answer
Tx based on sx - cosmetic surgery for adenoma sebaceum Simple partial or complex partial seizures can be controlled w/ oxcarbazepine or carbamazepine; lamotrigine for generalized seizures. - infantile spasms: ACTH or vigabatrin Surgical intervention indicated in setting of increased ICP or for seizures assoc w/ epileptogenic focus or severe developmental delay
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What is aphasia?
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general term for speech and language disorders - results from insults (stroke, tumors, abscesses) to the "dominant hemisphere"
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What is broca's aphasia?
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disorder of language production, including writing w/ intact comprehension. Expressive/nonfluent aphasia Due to insult to Broca's area in the posterior inferior frontal gyrus. Secondary to left superior MCA stroke AKA motor aphasia
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How does Broca's aphasia present?
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impaired repetition, frustration w/ awareness of deficits, arm and facial hemiparesis, hemisensory loss, apraxia of the oral muscles. Speech is described as "telegraphic" and agrammatical w/ frequent pauses
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How is Broca's aphasia tx?
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speech tx (varying outcomes)
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What is Wernicke's aphasia?
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disorder of language comprehension w/ intact yet nonsenical production. Also known as sensory aphasia. Fluent/receptive aphasia due to insult to Wernicke's area in the left posterior superior temporal (perisylvian) gyrus. Often secondary to left inferior/posterior MCA embolic stroke
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How does Wernicke's aphasia present?
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preserved fluency of language w/ impaired repetition and comprehension, leading to "word salad" Pts cannot follow commands; make frequent use of neologisms (made-up words) and paraphasic errors (word substitutions) Show lack of awareness of deficits and exhibit right upper homonymous quadrantanopia secondary to involvement of Meyer's loop
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How is Wernicke's aphasia tx?
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tx the underlying etiology and institute speech tx
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What is a coma?
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state of unconsciousness marked by profound suppression of responses to external and internal stimuli (state of unarousable unresponsiveness).
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What are lesser states of impaired arousal?
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obtundation or stupor
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What causes coma?
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catastrophic structural CNS injury or diffuse metabolic dysfxn coma indicates bilateral dysfxn of both cerebral hemispheres or the brain stem (pons or higher); when structural, coma usually results from bilateral pathology. Causes: - diffuse hypoxic/ischemic encephalopathy (e.g. postcardiac arrest) - diffuse axonal injury from high-acceleration trauma (MVA) - brain herniation (e.g. cerebral mass lesion, SAH w/ obstructive hydrocephalus) - widespread infection (e.g. viral encephalitis or advanced bacterial meningitis) - massive brain stem hemorrhage or infarction (e.g. pontine myelinolysis) - electrolyte disturbances (e.g. hypoglycemia) - exogenous toxins (e.g. opiates, benzodiazepines, EtOH, other drugs). - generalized seizure activity or postictal states - endocrine (e.g. severe hypothyroidism) or metabolic dysfxn (e.g. thiamine deficiency)
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How does coma present?
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Impt questions: ask witnesses complete hx including meds Thorough med and neuro exam - mental status (GCS) - spontaneous motor activity - muscular tone - breathing pattern - fundoscopy - pupillary response - eye movts (including doll's eye maneuver if the neck has been cleared from fracture) - corneal reflex - cold-water caloric testing - gag reflex - motor/autonomic responses to noxious stimuli applied to limbs, trunk and face (retromandibular pressure, nasal tickle)
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How is coma dx?
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Clinical dx, lab tests, neuroimaging Labs: Glu, electrolytes, calcium, renal panel, LFTs, ABG, toxicology screen, blood and CSF cultures. TSH (if suspicious) Imaging: head CT w/o contrast FIRST then LP if needed (worry about risk of herniation). MRI to check for structural changes and ischemia EEG R/o catatonia, hysterical or conversion unresponsiveness, "locked-in" syndrome, persistent vegetative state
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What is locked-in syndrome?
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pts are awake and alert but can move only their eyes and eyelids Assoc w/ central pontine myelinolysis, brain stem stroke, and advanced ALS
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What is persistent vegetative state?
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characterized by normal wake-sleep cycles but lack of awareness of self or the environment. Most common causes are trauma w/ diffuse cortical injury or hypoxic ischemic injury
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How is coma tx?
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STABILIZE pt: ABCs Reverse the reversible: dextrose, oxygen, naloxone, thiamine ID and tx underlying cause and assoc complications Prevent further damage
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What distinguishes coma and brain death?
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brain death has lack of respiratory drive
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What are the s/sx of thiamine deficiency (vitamin B1)--> Wernicke's encephalopathy?
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Classic Triad: - encephalopathy (disorientation, inattentiveness, confusion, coma) - ophthalmoplegia (nystagmus, lateral rectus palsy, conjugate gaze palsy, vertical gaze palsy) - ataxia (polyneuropathy; cerebellar and vestibular dysfxn leading to problems standing or walking)
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Who are classic pts to present w/ Wernicke's encephalopathy?
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alcoholics, hyeremesis, starvation, renal dialysis, AIDS. also can be brought on/exacerbated by high-does glu admin
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How is Wernicke's encephalopathy tx?
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reversible almost immediately w/ thiamine admin. always give thiamine before glu
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What are the s/sx of Korsakoff's dementia?
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due to thiamine (B1) deficiency Wernicke's encephalopathy + anterograde and retrograde amnesia, horizontal nystagmus, and confabulations
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Who are the classic pts to present w/ Korsakoff's dementia?
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Alcoholics, hyperemesis, starvation, renal dialysis, AIDS. Usually occurs in the "resolution" phase of Wernicke's syndrome that was treated late or inadequately
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How is Korsakoff's dementia tx?
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irreversible
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What are the s/sx of vitamin B12 deficiency?
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-->Combined system disease (CSD) or subacute combined degeneration of the posterior and lateral columns of the spinal cord (see the discussion of clinical neuroanatomy); peripheral neuropathy. Gradual, progressive onset. Symmetric paraesthesias, stocking-glove sensory neuropathy, leg stiffness, spasticity, paraplegia, bowel and bladder dysfxn, sore tongue. Dementia
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Who are the classic pts to present w/ vitamin B12 deficiency?
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pernicious anemia; strict vegetarians, s/p gastric or ileal resection; ileal disease (Crohn's); alcoholics or others w/ malnutrition
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How is vitamin B12 deficiency tx?
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B12 injections or large oral doses
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What are the s/sx of folate deficiency?
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irritability; personality changes w/o neurologic sx of CSD
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Who are the class pts to present w/ folate deficiency?
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alcoholics; pts w/ pernicious anemia
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How is folate deficiency tx?
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reversible if corrected early
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What is glaucoma?
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any process that disrupts the natural flow of aqueous humor produced by the ciliary body on the iris--> increased intraocular pressure (IOP), damaging the optic nerve and causing visual field deficits Glaucoma = result of damage to the nerve
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Which is more common in the US, open or closed angle glaucoma?
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open angle glaucoma
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What is closed angle glaucoma?
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occurs when the iris dilates and pushes against the lens of the eyes, disrupting flow of aqueous humor into the anterior chamber. pressure in the posterior chamber then pushes the peripheral iris forward and blocks the angle
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What are risk factors for closed angle glaucoma?
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Fhx older age Asian ethnicity hyperopia prolonged pupillary dilation (prolonged time in a dark area, stress, medications) anterior uveitis lens dislocation
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How does closed-angle glaucoma present?
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classically presents w/ extreme eye pain, blurred vision, headache, nausea, and vomiting. hard, red eye is seen (from acute closure of a narrow anterior chamber angle) Pupil is dilated and nonreactive to light IOP is increased resolves spontaneously prior to presentation (pupillary constriction in sunlight) opthalmologic exam reveals narrow angles in one or both eyes
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How is closed-angle glaucoma dx?
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based on clinical hx and exam mimic migraine headache w/ blurred vision (clue is that it is triggered by darkness-->pupillary dilation, rather than bright light like migraines)
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How is closed-angle glaucoma tx?
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MEDICAL EMERGENCY-->blindness Tx to decrease IOP via eyedrops (Timolol, pilocarpine, apraclonidine) or systemic meds (oral or IV acetazolamide, IV mannitol) Laser peripheral iridotomy, creates a hole in the peripheral iris, is curative and may be performed prophylactically
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What is open-angle glaucoma?
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flow of aqueous humor through trabecular meshwork is limited, increasing IOP diseased trabecular meshwork obstructs proper drainage of eye, leading to a gradual increase in pressure and progressive vision loss
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What is the definition of right anopia?
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defect in R eye
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What is the definition of bitemporal hemianopia?
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defect in L and R temporal halves
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What is the def of left homonymous hemianopia?
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defect in L halves of both eyes
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What is the def of left upper quadrantic anopia?
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suggests right temporal lesion left upper quadrant defect in both eyes
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What is the def of left lower quadrantic anopia?
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suggests right parietal lesion left lower quadrant defect in both eyes
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What is the def of left hemianopia w/ macular sparing?
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defect in left halves of both eyes except spare center
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What are the risk factors for open-angle glaucoma?
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>40yo African American ethnicity diabetes myopia
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How does open-angle glaucoma present?
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ASx until late in clinical course, when pts may begin to notice visual deficits Should be suspected in pts >35yo who need frequent lens changes and have mild headaches, visual disturbances, and impaired adaptation to darkness. earliest visual defect is seen in the peripheral nasal fields Exam: cupping of optic nerve head is seen on fundoscopic exam
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How is open-angle glaucoma dx?
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Tonometry, opthalmoscopic visualization of the optic nerve and visual field testing
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How is open-angle glaucoma tx?
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topical B-blocks (timolol, betaxolol) to decrease aqueous humor production or w/ pilocarpine to increase aqueous outflow. Carbonic anhydrase inhibitors may also be used. If meds fail, laser trabeculoplasty or a trabeculectomy can improve aqueous drainage
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What is age-related macular degeneration (AMD) and how does it present?
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painless loss of central vision atrophic (dry) macular degeneration: 80% cases. Causes gradual vision loss Exudative or neovascular (wet) macular degeneration: much less common, but assoc w/ more rapid and severe vision damage
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What is the leading cause of permanent bilateral visual loss in the elder in the US?
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macular degeneration
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How is AMD dx?
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fundoscopic exam: drusen and/or pigmentary changes in pts w/ atrophic AMD hemorrhage and subretinal fluid are suggestive of exudative AMD
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How is atrophic AMD tx?
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no tx available Vitamins slow progression of disease - C, E, beta-carotene, zinc Increase in mortality rate from high doses of vitamin E and an elevated lung cancer incidence among individuals on beta-carotene supplementation, so modify regimen for smokers
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How is exudative AMD tx?
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VEGF inhibitors to improve vision (ranibizumab, bevacizumab) or slow visual loss (pegaptanib) in pts w/ exudative AMD photodynamic tx w/ verteporfin (laser to selectively target retinal vessels) may be useful in conjxn w/ VEGF inhibitors
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What is retinal vascular occlusion and how does is present?
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Seen in elderly and often idiopathic Central retinal artery occlusion: - sudden, painless, unilateral blindness - pupil reacts to near stimulus, but is sluggishly reactive to direct light - present w/ a cherry-red spot on the fovea and retinal swelling (whittish appearance to the nerve fiber layer), and retinal arteries that may appear bloodless Central retinal vein occlusion: - characterized by rapid, painless vision loss of variable severity - choked, swollen optic disk w/ hemorrhages, venous stasis retinal hemorrhages, cotton-wool spots, and edema of the macular may be seen on exam.
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How is central retinal artery occlusion tx?
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intra-arterial thrombolysis of the ophthalmic artery w/in 8 hrs of onset of sx other tx of unclear benefit - increasing IOP through drainage of anterior chamber of IV acetazolamide
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How is central retinal vein occlusion tx?
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laser photocoagulation has variable results
