title: Cerebellar activation during ataxic gait in olivopontocerebellar atrophy: a PET study.
abstract: OBJECTIVE
  To investigate the possible abnormal regional brain metabolism during ataxic gait in olivopontocerebellar atrophy (OPCA), and to evaluate the response of the cerebellar subregions to instability during bipedal gait.
  
  
  METHODS
  On 9 patients with OPCA in early phase and on 10 age-matched normal subjects, we performed positron emission tomography (PET) with 2-[18F]fluoro-2-deoxy-D-glucose (FDG) under two different conditions: supine resting and 30 min treadmill walking.
  
  
  RESULTS
  Both in normals and in patients with OPCA, the FDG uptake in the walking state (Uwalk) was significantly greater than that in the resting state (Urest) in the pyramis, declive-folium-tuber and culmen of the cerebellar vermis, and in the thalamus. In the patients, the Uwalk was also significantly greater than the Urest in the posterior lobe of cerebellar hemisphere and in the pons and midbrain. In the pyramis, the activation ratio (= Uwalk/Urest) of the patients was significantly lower than that of the normals.
  
  
  CONCLUSIONS
  We considered that these findings reflect the pathophysiology of ataxic gait in OPCA patients and the compensatory mechanism for the instability during ataxic gait.
authors.affiliation: Second Department of Internal Medicine, Nippon Medical School, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Mishina
authors.forename: M
authors.initials: M
authors.lastname: Senda
authors.forename: K
authors.initials: K
authors.lastname: Ishii
authors.forename: M
authors.initials: M
authors.lastname: Ohyama
authors.forename: S
authors.initials: S
authors.lastname: Kitamura
authors.forename: Y
authors.initials: Y
authors.lastname: Katayama
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002531:Cerebellum / Q000000981:diagnostic imaging / Q000378:metabolism*; D005080:Exercise Test; D005260:Female; D019788:Fluorodeoxyglucose F18; D020234:Gait Ataxia / Q000000981:diagnostic imaging / Q000209:etiology / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009849:Olivopontocerebellar Atrophies / Q000150:complications / Q000000981:diagnostic imaging / Q000378:metabolism*; D019275:Radiopharmaceuticals; D013788:Thalamus / Q000378:metabolism; D014055:Tomography, Emission-Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18