Surgical Management for Dystonia: Efficacy of Deep Brain Stimulation in the Long Term

Walaa A Kamel; Pritam Majumdar; Georgios Matis; Albert J Fenoy; Shankar Balakrishnan; Ali T Zirh; Aslihan Cevik; Amit Kumar Tomar; Naoufel Ouerchefani

doi:10.3390/neurolint13030037

Surgical Management for Dystonia: Efficacy of Deep Brain Stimulation in the Long Term

Neurol Int. 2021 Aug 2;13(3):371-386. doi: 10.3390/neurolint13030037.

Authors

Walaa A Kamel^{1

2}, Pritam Majumdar³, Georgios Matis³, Albert J Fenoy⁴, Shankar Balakrishnan⁵, Ali T Zirh⁶, Aslihan Cevik⁷, Amit Kumar Tomar⁸, Naoufel Ouerchefani⁹

Affiliations

¹ Neurology Department, Faculty of Medicine, Beni-Suef University, Beni-Suef 62511, Egypt.
² Neurology Department, Ibn-Sina Hospital, Kuwait City 25427, Kuwait.
³ Department of Stereotactic and Functional Neurosurgery, University Cologne Hospital, 50931 Cologne, Germany.
⁴ Department of Neurosurgery, McGovern Medical School, The University of Texas at Houston, UTHealth Neurosciences, Houston, TX 77030, USA.
⁵ Department of Neurology and Neuromodulation, MIOT International Hospital, Hennai 600089, India.
⁶ Department of Neurosurgery, Istanbul Medipol University, Istanbul 34810, Turkey.
⁷ Department of Neurosurgery, Istanbul Aydin University, Istanbul Medical Park Florya, Istanbul 34295, Turkey.
⁸ Department of Anesthesia and Neurosurgery, Indo-Gulf Hospital, Noida 201301, India.
⁹ Department of Neurosurgery, Foch Hospital, 92150 Paris, France.

Abstract

Introduction: Dystonia is a movement disorder substantially affecting the quality of life. Botulinum Neurotoxin (BoNT) is used intramuscularly as a treatment for dystonia; however, not all dystonia patients respond to this treatment. Deep brain stimulation (DBS) is an established treatment for Parkinson's disease (PD) and essential tremor, but it can help in dystonia as well.

Objectives: We studied a total of 67 dystonia patients who were treated with DBS over a period of 7 years to find out the long-term efficacy of DBS in those patients. First, we calculated patient improvement in post-surgery follow-up programs using the Global Dystonia Severity scale (GDS) and Burke-Fahn-Marsden dystonia rating scale (BFMDRS). Secondly, we analyzed the scales scores to see if there was any statistical significance.

Methods: In our study we analyzed patients with ages from 38 to 78 years with dystonia who underwent DBS surgery between January 2014 and December 2020 in four different centers (India, Kuwait, Egypt, and Turkey). The motor response to DBS surgery was retrospectively measured for each patient during every follow-up visit using the GDS and the BFMDRS scales.

Results: Five to 7 years post-DBS, the mean reduction in the GDS score was 30 ± 1.0 and for the BFMDRS score 26 ± 1.0. The longitudinal change in scores at 12 and 24 months post-op was also significant with mean reductions in GDS and BFMDRS scores of 68 ± 1.0 and 56 ± 1.0, respectively. The p-values were <0.05 for our post-DBS dystonia patients.

Conclusions: This study illustrates DBS is an established, effective treatment option for patients with different dystonias, such as generalized, cervical, and various brain pathology-induced dystonias. Although symptoms are not completely eliminated, continuous improvements are noticed throughout the post-stimulation time frame.

Keywords: Burke–Fahn–Marsden dystonia rating scale (BFMDRS); Global Dystonia Severity scale (GDS); deep brain stimulation (DBS); globus pallidus interna (GPi); subthalamic nucleus (STN).