Deep Brain Stimulation in Parkinson's Disease: Assessing Efficacy

Parkinson's disease (PD) has a chronic course. Currently, levodopa is the mainstay of treatment. However, long-term use of levodopa is interrupted by several side effects like dyskinesia and on-off fluctuations. Other pharmacological treatments also have adverse drug profiles and do not provide long-term relief, warranting the need for novel therapeutic approaches with a long-term efficacy profile in PD. Deep brain stimulation (DBS) is one such evolving technology with proven efficacy in advanced PD and promising results in early PD. DBS is mainly of two types, open- and closed-loop, of which open loop has been in routine use but closed loop is an innovative technology, only recently introduced for the treatment of PD. Apart from cost, DBS technology faces major challenges that hamper its integration into mainstream treatment paradigm of PD. Most of these challenges, including the cost can be overcome or considerably reduced by selecting the right DBS type, the right target for stimulation and the right patient selection. The review, therefore, assesses the efficacy of different parameters involved in selection of DBS as a treatment strategy such as patient characteristics, target characteristics, pros and cons of different DBS strategies, safety of DBS and stage of PD. The review may help clinicians to effectively use all these parameters to improve the outcomes of DBS.