title: Neuropsychological functions and rCBF SPECT in Parkinson's disease patients considered candidates for deep brain stimulation.
abstract: OBJECTIVE
  In the present study, we examined relationships between neuropsychological functions and brain single photon emission computed tomography (SPECT) regional cerebral blood flow (rCBF) observed at presurgical evaluation for deep brain stimulation (DBS) of the subthalamic nucleus (STN) in advanced Parkinson's disease (PD) patients.
  
  
  METHODS
  Twenty advanced non-demented PD patients, candidates for DBS surgery, underwent perfusion brain SPECT study and neuropsychological assessment prior to surgery (range: 30-50 days). Patients were further assessed using the Unified Parkinson's Disease Rating Scale (UPDRS) and Hoehn and Yahr (H&Y) scale. During all assessments patients were "on" standard medication. NeuroGam software, which permits voxel by voxel analysis, was used to compare the brain perfusion of PD patients with a normal database adjusted for sex and age. Neuropsychological scores were compared to age, education and sex-adjusted normative databases.
  
  
  RESULTS
  Our results indicated that the distribution of rCBF showed significant differences when compared to an age- and sex-adjusted normative database. We found impaired blood flow in 17 (85%) of our patients in the left prefrontal lobe, in 14 (70%) in the right prefrontal lobe and in 11 (55%) in the left frontal and right parietal lobes. Neuropsychological testing revealed that 18 (90%) of our patients had significant impairments in measures of executive functions (set-shifting) and 15 (75%) in response inhibition. Furthermore, we found significant correlations between measures of visual attention, executive functions and the right frontal lobe region.
  
  
  CONCLUSIONS
  The presence of widespread blood flow reduction was observed mainly in the frontal lobes of dementia-free patients with advanced PD. Furthermore, performance on specific cognitive measures was highly related to perfusion brain SPECT findings.
authors.affiliation: Department of Nuclear Medicine, University of Patras Medical School, Patras, Greece.
authors.forename: Anna
authors.initials: A
authors.lastname: Paschali
authors.forename: Lambros
authors.initials: L
authors.lastname: Messinis
authors.forename: Epameinondas
authors.initials: E
authors.lastname: Lyros
authors.forename: Costas
authors.initials: C
authors.lastname: Constantoyannis
authors.forename: Zinovia
authors.initials: Z
authors.lastname: Kefalopoulou
authors.forename: Velissarios
authors.initials: V
authors.lastname: Lakiotis
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Papathanasopoulos
authors.forename: Paulos
authors.initials: P
authors.lastname: Vassilakos
mesh_terms: D002560:Cerebrovascular Circulation; D046690:Deep Brain Stimulation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology* / Q000628:therapy*; D020531:Subthalamic Nucleus; D015899:Tomography, Emission-Computed, Single-Photon