title: Eye movements in Parkinson's disease: before and after pallidotomy.
abstract: OBJECTIVE
  To evaluate the effects of unilateral, stereotactic, posteroventral pallidotomy on saccadic eye movements in patients with Parkinson disease (PD).
  
  
  METHODS
  Eye movements of 31 patients with moderate to advanced PD were recorded with an infrared system 1 month before and 3 months after pallidotomy. Two kinds of saccade tasks were used: saccade tasks for eliciting visually guided saccades and saccade tasks for eliciting internally mediated saccades (memory-guided, predictive, and anti-saccades). Latency, accuracy, peak velocity, and other parameters of saccades were evaluated.
  
  
  RESULTS
  Internally mediated saccades were more impaired in patients with advanced PD compared with those with moderate PD. Pallidotomy did not affect visually guided saccades. After pallidotomy, the peak saccadic velocity of internally mediated saccades decreased.
  
  
  CONCLUSIONS
  Hence, although pallidotomy has led to improvements in other motor functions, none were observed in saccadic responses. Rather, several modest decrements, below the level of clinical significance and all in internally mediated saccades, were observed.
authors.affiliation: Department of Ophthalmology, Indiana University School of Medicine, Indianapolis 46202-5175, USA.
authors.forename: T
authors.initials: T
authors.lastname: Blekher
authors.forename: E
authors.initials: E
authors.lastname: Siemers
authors.forename: L A
authors.initials: LA
authors.lastname: Abel
authors.forename: R D
authors.initials: RD
authors.lastname: Yee
mesh_terms: D000368:Aged; D005260:Female; D005917:Globus Pallidus / Q000601:surgery*; D006801:Humans; D008297:Male; D008568:Memory; D008875:Middle Aged; D010300:Parkinson Disease / Q000503:physiopathology* / Q000601:surgery*; D012438:Saccades / Q000502:physiology*; D013238:Stereotaxic Techniques