Deep Brain Stimulation and Parkinson’s Essay Example

to the general population's chance of one to two percent. The root causes of PD are currently under investigation by scientists who are exploring genetic and environmental factors. Research has revealed that individuals who have an immediate family member like a parent or sibling with PD have twice to thrice higher chances of acquiring the illness than those without affected relatives (Benabid et al., 1999).

Scientists have identified thirteen genes, including PARK1, DJ-1 (PARK7), Pink1 (Park6), dardarin (DRDN), Tau, lrrk2, parkin, uchl-1, park3, park9, park10 and park11 (Ascone et al., 2002), that are linked to Parkinson's disease and may affect when it develops. Although genetics play a limited role in PD cases, they are actively being studied as laboratory research on these forms can provide insight into the rare genetic variations of PD which can lead to a better understanding of the disease overall. While environmental factors such as injury or toxins are suspected to trigger PD, there is no definitive proof and they may influence other bodily factors rather than being a singular cause.

Epidemiological studies have pointed out that rural living, well water, and exposure to herbicides and pesticides could be associated with Parkinson's Disease (PD) (Sringhouse, 2005). Although these environmental factors may not provide clues to the cause of PD in a specific individual, they are useful for investigating their effects on PD models in laboratories. Individuals with PD may present different symptoms which develop differently over time, but ultimately the disease leads to disability.

At the onset of Parkinson's disease, individuals may experience tremors in their hands, arms, legs and face. They may also feel irritable or depressed. As the illness advances, stiffness

can emerge in the trunk, arms and legs which can lead to delayed movement or bradykinesia. Furthermore, after a number of years muscle freezing or "freeze", also called akinesia might transpire.

People with Parkinson's disease are at a higher risk of falling because their balance and coordination are impaired, in addition to experiencing bradykinesia and akinesia. Digestive system slowdown causes symptoms like constipation, fatigue, and weakness. Fainting spells can occur due to hypotension. Ultimately, individuals living with Parkinson's disease display distinct physical characteristics such as a shuffling gait, hunched posture, and vacant stare.

PD is a disease that is both complex and debilitating, gradually causing severe disability. It affects movement and produces various other problems for patients, including difficulties with eating and speaking, urinary or digestive issues, skin problems, emotional changes, and sleep disturbances.

The manifestation and severity of Parkinson's disease symptoms are unpredictable, with no guaranteed effect on each patient. While these secondary symptoms are non-fatal, difficulty swallowing might result in choking incidents. The disease's progression in a person may span over two decades or longer, but some individuals experience a much faster onset.

Parkinson's Disease impacts the basal ganglia, an essential part of the brain for regulating movement. Specifically, the substantia nigra - which contains neurons transmitting dopamine signals - is affected. Axons transmit these signals to the striatum, ultimately controlling normal bodily movements.

Individuals with Parkinson's disease experience the degeneration of substantia nigra neurons, causing dopamine loss. This results in excessive firing of nerve cells in the striatum, leading to impairment of motor control. Ultimately, up to 80% of their dopamine-producing cells may be depleted.

Parkinson's Disease is characterized by the presence of Lewy neuritis which are

nerve fibers that contain enlarged alpha-synuclein and other proteins. This accumulation of alpha-synuclein can disrupt neuronal functions, including the transmission of nerve signals. The most common pharmacological treatments for managing Parkinson's Disease include dopaminergic drugs, decarboxylase inhibitors, dopamine agonists, and anticholinergics.

Dopaminergic drugs, such as levodopa, are commonly used to alleviate symptoms of Parkinson's disease by mimicking dopamine. However, while effective in addressing depleted dopamine levels in those with the condition, levodopa treatment does not prevent progressive brain changes linked to Parkinson's and may trigger adverse effects due to its conversion into dopamine before reaching the brain. Alternatively, dopamine agonists can bind to dopamine receptors and replicate its impact.

Anticholinergics, a type of medication that relaxes smooth muscle, are primarily administered to alleviate tremors in individuals with Parkinson’s disease. Some newly developed drugs have been authorized for use while others continue to undergo research both locally and abroad, with the aim of achieving superior therapeutic outcomes with minimal side effects ("Deep brain," 2003). Although medication can enhance motor functions, it may eventually become ineffective or lead to considerable adverse reactions as the illness progresses. Consequently, the dosage required to regulate motor function may escalate beyond an individual's tolerance level. In addition to drug therapies, surgical interventions such as lesioning or pallidotomy and deep brain stimulation are also available. Pallidotomy involves eliminating a specific area of the brain responsible for regulating movement control within the basal ganglia.

When it comes to the treatment of Parkinson’s disease symptoms, two options are pallidotomy and deep brain stimulation (DBS). Pallidotomy destroys brain tissue, which can lead to adverse effects such as hemorrhage, weakness, visual and speech deficits, and confusion. On the

other hand, DBS involves surgically implanting an electrode into the brain that sends continuous electrical signals to the part of the brain controlling movement, blocking abnormal signals causing tremors and rigidity. DBS offers several advantages over drug therapy and lesion surgery such as not intentionally damaging any part of the brain. (“Deep brain”, 2003)

In addition, external modifications can be made to the electrical stimulation in order to adapt to changes in a patient's condition. Pallidotomy is an invasive procedure that may hinder future treatments like brain cell transplantation due to concerns about its impact on patients' ability to benefit from them. Conversely, deep brain stimulation poses no such risk since it can be safely turned off and removed without damaging the brain - something that is not possible with pallidotomy. Furthermore, if the stimulator causes excessive side effects, it can be deactivated at any time.

DBS is a secure method that effectively addresses major symptoms of Parkinson's disease, thus leading to significant improvement in an individual's daily life tasks and overall quality of living. Prior to the development of DBS, surgical treatments for PD involved pallidotomy, a procedure where selected brain tissues were irreversibly destroyed to alleviate tremors and rigidity ("Treatment options", 2010). Unfortunately, such destructive procedures often resulted in unpleasant side effects, causing a shift from surgery to drug therapy once levodopa became available for PD in the 1960s.

In the 1980s, tremors in patients with essential tremor were found to be blocked with chronic thalamic stimulation in France, which led to a new era of surgical treatments using brain stimulation (Springhouse, 2005). Research studies using a monkey model for PD in France discovered altered

brain circuits specific to the disease and identified the subthalamic nucleus as a key target for stimulation (Bennazzouz, Gross, Feger, Boraud, & Biolac, 1993). Further investigations showed that stimulation of the subthalamic nucleus in PD patients caused significant improvements in tremors, slowness and stiffness. DBS is an implanted electrode treatment connected to an external pulse generator device that can easily be controlled. By reducing the need for levodopa, it minimizes the involuntary bodily movements that typically arise from levodopa administration.

Deep brain stimulation (DBS) is a treatment that can help alleviate fluctuations of symptoms and reduce tremors, slowness of movements, and gait problems for those with Parkinson’s disease. Unlike pallidotomy, DBS is reversible. According to Bennazzouz et al (1998), over 70% of individuals experience significant improvement across all their symptoms related to Parkinson's disease with DBS. Following the procedure, most people are able to significantly reduce their medications. In an experiment featured in the New England Journal of Medicine, 96 patients with advanced Parkinson's disease underwent bilateral DBS, wherein electrodes were implanted in the subthalamic nucleus.

The study conducted by "DBS of the" (2001) revealed that after three months of performing the procedures, subthalamic nucleus stimulation resulted in a motor score improvement (P ;lt; 0). Patients also experienced an increase in good mobility time without involuntary movements from preoperative to six-month visits, which rose from 27 percent to 74 percent(P ;lt; 0.001) with subthalamic stimulation. Ultimately, the experiment concluded that bilateral stimulation of the subthalamic nucleus significantly enhanced motor function among Parkinson's disease patients who were unable to benefit from medical therapy.

There has been notable advancement in the search for a cure for Parkinson's disease. Despite

its complexity, it is now considered possible to halt its progression, recover lost abilities, and prevent its onset. Studies have enhanced our understanding of PD's development by exploring environmental risks and genes that increase susceptibility. Additionally, several promising treatments are in development, such as DBS which is currently undergoing lab trials.

Continued research aims to improve understanding of Parkinson's disease and its underlying principles, potentially leading to better symptom management for patients and the prevention or cessation of the disease. The U.S. Food and Drug Administration has approved DBS as a treatment option for PD, dystonia, and essential tremor. Meanwhile, scientists are investigating its potential effectiveness in treating other conditions such as Tourettes syndrome, epilepsy, and depression. Ongoing efforts focus on enhancing the efficacy of DBS.

Currently, clinical research is focused on finding the optimal brain region for stimulation and assessing the therapy's long-term results. Furthermore, scientists are striving to enhance DBS technology. As numerous PD patients cannot be successfully treated with medicine, DBS has become a crucial intervention. With increasing support from studies, it is likely that DBS will become a widely available therapeutic option for PD patients worldwide. Neuroscientists can use DBS to precisely locate affected areas of the brain and determine where stimulation could alleviate symptoms related to PD.

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