(Kiosk 5) Extended Resolution of Severe Cervical Torsion Dystonia in Young Adult with DYT1 Dystonia and Chronic Deep Brain Stimulator (DBS) Implant After Single Injection of Botulinum Toxin

Case Diagnosis: 24-year-old male with DYT1 dystonia presenting with severe cervical torsion dystonia.

Case Description or Program Description: The patient initially presented to neurology in 2007 with new onset right writer’s cramp dystonia and left foot dystonia, he was diagnosed with early-onset isolated dystonia (DYT1). Several medications were trialed with minimal benefit including baclofen, clorazepate, and trihexyphenidyl. Symptoms progressed to generalized dystonia. In 2008, the patient underwent bilateral globus pallidus internus (GPI) deep brain stimulation (DBS). His ambulation improved but with mild residual cervical dystonia (right head side bending with left rotation). In 2018, a car accident resulted in increased dystonia and new significant pain and spasms in the right trapezius muscle. In 2021, his DBS stopped working and despite switching implant brands still saw worsening of his baseline dystonia. On evaluation by physiatry, the cervical dystonia had progressed to the point where he could no longer hold his head upright without using his right hand. He became disabled from work, driving, and social activities. Despite the presence of the active DBS implant, we trialed botulinum toxin type A injection due to his poor quality of life.

Setting: Outpatient clinic, University-based

Assessment/Results: 30 units to right sternocleidomastoid (three sites), 30 units to right trapezius (three sites), and 20 units to right levator scapulae were injected. Three weeks post procedure he had near resolution of cervical dystonia with full upright posture (without hand support) and no pain. Patient was seen most recently seven months post-injection with continued resolution of torticollis. He was back at work, driving, and engaging in social activities.

Discussion (relevance): This is the first reported case, to our knowledge, where injecting botulinum toxin for focal cervical dystonia in the setting of co-existing DBS related to DYT1 dystonia resulted in extended successful outcome.

Conclusions: Cervical dystonia refractory to DBS may be effectively treated with botulinum toxin in patients with DTY1 dystonia.