title: Deep brain stimulation or thalamotomy in fragile X-associated tremor/ataxia syndrome? Case report.
abstract: We present the case of a 66-year-old man who has been treated for essential tremor since the age of 58. He developed mild cerebellar gait ataxia seven years after tremor onset. Moderate, global brain atrophy was identified on MRI scans. At the age of 68, only temporary tremor relief could be achieved by bilateral deep brain stimulation of the ventral intermedius nucleus of the thalamus. Bilateral stimulation of the subthalamic nucleus also resulted only in transient improvement. In the meantime, progressive gait ataxia and tetraataxia developed accompanied by other cerebellar symptoms, such as nystagmus and scanning speech. These correlated with progressive development of bilateral symmetric hyperintensity of the middle cerebellar peduncles on T2 weighted MRI scans. Genetic testing revealed premutation of the FMR1 gene, establishing the diagnosis of fragile X-associated tremor/ataxia syndrome. Although this is a rare disorder, it should be taken into consideration during preoperative evaluation of essential tremor. Postural tremor ceased two years later after thalamotomy on the left side, while kinetic tremor of the right hand also improved.
authors.affiliation: Department of Neurology, Semmelweis University, Budapest, Hungary. Electronic address: tamas.gertrud@med.semmelweis-univ.hu.
authors.forename: Gertrúd
authors.initials: G
authors.lastname: Tamás
authors.affiliation: Department of Neurology, University of Pécs, Pécs, Hungary.
authors.forename: Norbert
authors.initials: N
authors.lastname: Kovács
authors.affiliation: Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, Hungary.
authors.forename: Noémi Ágnes
authors.initials: NÁ
authors.lastname: Varga
authors.affiliation: MR Research Centre, Semmelweis University, Budapest, Hungary.
authors.forename: Péter
authors.initials: P
authors.lastname: Barsi
authors.affiliation: National Institute of Clinical Neurosciences, Budapest, Hungary.
authors.forename: Loránd
authors.initials: L
authors.lastname: Erőss
authors.affiliation: Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, Hungary.
authors.forename: Mária Judit
authors.initials: MJ
authors.lastname: Molnár
authors.affiliation: Department of Neurosurgery, University of Pécs, Pécs, Hungary.
authors.forename: István
authors.initials: I
authors.lastname: Balás
mesh_terms: D000368:Aged; D001259:Ataxia / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery / Q000628:therapy*; D046690:Deep Brain Stimulation / Q000379:methods*; D005600:Fragile X Syndrome / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery / Q000628:therapy*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D019635:Neurosurgical Procedures / Q000379:methods*; D020531:Subthalamic Nucleus / Q000000981:diagnostic imaging / Q000503:physiopathology; D013788:Thalamus / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome; D014202:Tremor / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery / Q000628:therapy*
keywords: Ataxia; Deep brain stimulation; Fragile X tremor/ataxia syndrome; Thalamotomy; Tremor