History of deep brain stimulation

Abstract

Electrical neuromodulation of the brain comprises stereotactic surgical interventions, primarily those focusing on neurophysiological functional alterations. The term “stereotactic surgery” refers to the discipline of accessing a definite targeted area within the nervous system with imaging, a Cartesian coordinate system and three-dimensional calculation system guidance. Stereotactic surgical techniques have advanced exponentially in the last 40 years. Utilization of new calculation techniques, invention of frameless systems and image-fusion with recently available software have contributed to implementation of minimal invasive surgical approaches and considerably decreased mistargeting. Actually, initial modern work attempts have been led by psychosurgery and lesioning procedures in the second quarter of previous century, which has recently advanced to a gold standard in surgery for movement disorders via deep brain stimulation (DBS). Implementation of DBS surgery has led to lesser use of lesioning surgery. Nowadays, determination and restoration of the symptom-specific nucleus by stimulation is aimed and can be achieved. Despite all these developments and success in the field, the exact mechanisms of deep brain stimulation have not been clearly explained yet. A possible modulation of dataflow in adjacent basal ganglio-thalamo-cortical pathways by an efferent GABAergic and glutamatergic inhibitory and excitatory complex pathway output arising from nuclei stimulated by DBS is generally accepted. In the last 25 years, many animal studies have focused on the anatomy, physiology and interactions of basal ganglia with one another and with target neural areas in different disorder scenarios. Deep Brain Stimulation surgery along with the radiosurgery is the most intriguing and fast developing field in neurosurgery. Its efficacy on hypokinetic and hyperkinetic movement disorders has been proven and utility in psychosurgery is recently under research. First application for an electronic stimulation system for use in Parkinson’s disease patients to US Food and Drug Administration (FDA) department was carried out by an American company ‘Medtronic’ in March 1997. First research data including Unified Parkinson’s Disease Rating Scale (UPDRS) output have been presented to FDA. In advance, thalamic DBS for motor tremor in both Parkinson’s Disease and essential tremor was approved by FDA in 1997. The same company applied for approval to similar EU department for utilizing treatment in European countries in 1998. In 2003, sub thalamic nucleus (STN) DBS and Globus Pallidus internus (GPi) DBS for Parkinson’s Disease were approved by FDA. Afterwards, clinical use has extended to primary generalized and segmental dystonia in 2003, and obsessive compulsive disorder (OCD) in 2009 with ‘humanitarian device exemption’ (HDE) status of FDA. More recently, DBS surgery was approved by FDA for medically refractory epilepsy in 2018. Besides, DBS is recently in use successfully for disorders like Tourette’s syndrome and depression, and some case series in available literature state that the DBS can be utilized for various other disorders like headache, obesity and dementia. Reversibility of DBS effects encourage academic community for further researches. DBS procedure has been performed over 40.000 patients for Parkinson’s disease and essential tremor as of 2013. Recently, this number is estimated over 100,000. This new technology has built up hope particularly for Parkinson’s disease patients and their relatives.