title: Neuroanatomical substrates of visual hallucinations in patients with non-demented Parkinson's disease.
abstract: BACKGROUND
  Visual hallucinations (VH), which are common in patients with Parkinson's disease (PD), lead to increased disability and are a significant predictor of the development of dementia. However, the neuroanatomical basis for VH in non-demented PD patients remains controversial.
  
  
  METHODS
  A total of 110 patients with PD were classified into PD with VH (n=46) and PD without VH (n=64) groups, depending on the presence of VH assessed by the caregiver-based structured interview of the Neuropsychiatric Inventory. We performed voxel-based morphometry (VBM) for grey matter (GM) volume and a region-of-interest-based volumetric analysis of the substantia innominata (SI) between two groups.
  
  
  RESULTS
  The comprehensive neuropsychological assessment showed that PD patients with VH showed more severe cognitive deficits in delayed visual memory and frontal executive functions compared with those without VH. A VBM analysis revealed that PD patients with VH had significantly lower GM volume in the right orbitofrontal, left temporal and left thalamic areas compared with those without VH. The normalised SI volume was significantly reduced in PD patients with VH compared with those without VH (1.28 ± 0.22 vs 1.41 ± 0.25, p=0.005).
  
  
  CONCLUSIONS
  The present study demonstrates that non-demented PD patients with VH exhibited a smaller volume in the frontal, temporal and thalamic areas as well as the SI, suggesting that PD hallucinators may have distinctive neuroanatomical bases relative to PD non-hallucinators.
authors.affiliation: Department of Neurology and Brain Research Institute, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Soojeong
authors.initials: S
authors.lastname: Shin
authors.forename: Ji Eun
authors.initials: JE
authors.lastname: Lee
authors.forename: Jin Yong
authors.initials: JY
authors.lastname: Hong
authors.forename: Mun-Kyung
authors.initials: MK
authors.lastname: Sunwoo
authors.forename: Young Ho
authors.initials: YH
authors.lastname: Sohn
authors.forename: Phil Hyu
authors.initials: PH
authors.lastname: Lee
mesh_terms: D000368:Aged; D001921:Brain / Q000473:pathology; D003071:Cognition; D005260:Female; D006212:Hallucinations / Q000209:etiology / Q000473:pathology* / Q000523:psychology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory; D009460:Neurologic Examination; D009483:Neuropsychological Tests; D010275:Parasympathetic Nervous System / Q000473:pathology; D010300:Parkinson Disease / Q000150:complications / Q000473:pathology* / Q000523:psychology; D012959:Socioeconomic Factors; D013377:Substantia Innominata / Q000473:pathology