Supplementary Material for: Globus Pallidus Interna Deep Brain Stimulation Improves Chorea and Functional Status in a Patient with Chorea-Acanthocytosis

We report a 39-year-old woman with chorea-acanthocytosis (ChAc) who was referred with refractory hyperkinetic movement and truncal bending spasm. She was diagnosed with ChAc with clinical features and laboratory findings of acanthocytosis in peripheral blood smear, and genetic studies revealed novel mutations in the VPS13 gene. Because her symptoms did not respond well to medical treatment, she was in a totally dependent state. We decided to perform globus pallidus interna deep brain stimulation (GPi-DBS) for symptom control. After the operation her hyperkinetic movement, bradykinesia, and truncal bending motion were improved, the preoperative total score of the motor section on the Unified Huntington’s Disease Rating Scale (UHDRS) was 44, the independence scale was 50, and functional capacity was 1. However, a year after GPi-DBS, the postoperative score on the motor section was 12, the independence scale was 80, functional capacity was 9, and she had become capable of independent daily life. Although there is currently no curative treatment for ChAc, GPi-DBS represents a promising option for symptomatic control.