title: Cognition following bilateral implants of embryonic dopamine neurons in PD: a double blind study.
abstract: OBJECTIVE
  To determine if bilateral transplantation of embryonic mesencephalic dopamine cells into the putamen of patients with PD significantly affected their cognitive functioning when compared with patients receiving sham surgery and to examine the effect of age on cognitive performance after implantation.
  
  
  METHODS
  Forty patients (19 women, 21 men; age 34 to 75 years) with idiopathic PD of at least 7 years' duration (mean 14 years) who had disabling motor signs despite optimal drug management were randomly assigned to tissue implants or sham craniotomies in a double-blind design. Neuropsychological tests assessing orientation, attention, language, verbal and visual memory, abstract reasoning, executive function, and visuospatial and construction abilities were administered before and 1 year after surgery. Treatment groups did not differ at baseline in demographic, neuropsychological, motor, depression, or levodopa equivalent measures.
  
  
  RESULTS
  Postsurgical change in cognitive performance was not significantly different for real or sham surgery groups. Performance in both groups remained unchanged at follow-up for most measures.
  
  
  CONCLUSIONS
  Embryonic dopamine producing neurons can be implanted safely into the putamen bilaterally without impairing cognition in patients with PD, but within the first year, improved cognition should not be expected.
authors.affiliation: Cognitive Neuroscience Division, G.H. Sergievsky Center, New York, NY 10032, USA.
authors.forename: C T
authors.initials: CT
authors.lastname: Trott
authors.forename: S
authors.initials: S
authors.lastname: Fahn
authors.forename: P
authors.initials: P
authors.lastname: Greene
authors.forename: S
authors.initials: S
authors.lastname: Dillon
authors.forename: H
authors.initials: H
authors.lastname: Winfield
authors.forename: L
authors.initials: L
authors.lastname: Winfield
authors.forename: R
authors.initials: R
authors.lastname: Kao
authors.forename: D
authors.initials: D
authors.lastname: Eidelberg
authors.forename: C R
authors.initials: CR
authors.lastname: Freed
authors.forename: R E
authors.initials: RE
authors.lastname: Breeze
authors.forename: Y
authors.initials: Y
authors.lastname: Stern
mesh_terms: D000328:Adult; D000368:Aged; D000978:Antiparkinson Agents / Q000627:therapeutic use; D003131:Combined Modality Therapy; D003399:Craniotomy; D018450:Disease Progression; D004298:Dopamine / Q000378:metabolism*; D004311:Double-Blind Method; D005260:Female; D016332:Fetal Tissue Transplantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000378:metabolism / Q000637:transplantation*; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000523:psychology / Q000601:surgery*; D011699:Putamen; D014055:Tomography, Emission-Computed; D017211:Treatment Failure
chemical_list: D000978:Antiparkinson Agents; D004298:Dopamine