Parkinson’s Disease Pathophysiology and Comparative Analysis of the Efficacy Between Subthalamic Nucleus and Globus Pallidus Interna Deep Brain Stimulation: A Student’s Perspective

Parkinson’s Disease (PD) is becoming an increasingly common neurodegenerative disease across the world, presenting with both debilitating motor and non-motor symptoms that progressively worsen throughout the course of the disease. Prominent motor symptoms include tremors, bradykinesia, muscle rigidity, and postural/gait instabilities, while common non-motor symptoms include fatigue, pain, autonomic dysfunction (i.e., bowel and bladder dysfunction), mood disorders, and dementia. The advent of modern medical management of PD has introduced several different medications, the most popular being levodopa, that have shown success in reducing the severity of motor symptoms, particularly in the early stages of the disease. Throughout disease progression, however, many patients will eventually require a more comprehensive and flexible approach to managing their symptoms with medications, and in some cases, necessitating surgical intervention. Deep brain stimulation (DBS) for PD has been proven successful for several decades at providing temporary symptomatic relief in patients by introducing an electrical current that works to silence the activity of the pathological neurons involved in PD, thus helping to alleviate motor symptoms and often allowing for a significant reduction in cotreatment with medication. The most common brain regions for the DBS treatment in PD are the subthalamic nucleus (STN) and globus pallidus interna (GPi), both located within basal ganglia. Decades long research aimed at improving the delivery of DBS treatment has paved the way for paved the way for more precise delivery methods of DBS, such as adaptive DBS (aDBS) and bipolar stimulation. However, the overall efficacy of both STN and GPi DBS in curtailing motor symptoms continues to be at the top of the list for many researchers.