title: A multicenter brain perfusion SPECT study evaluating idiopathic normal-pressure hydrocephalus on neurological improvement.
abstract: OBJECTIVE
  This study was designed to investigate the specific cerebral blood flow (CBF) pattern in patients with idiopathic normal-pressure hydrocephalus (iNPH) and a predictive value for shunt responsiveness in a multicenter study (Study of Idiopathic Normal-Pressure Hydrocephalus on Neurological Improvement: SINPHONI).
  
  
  METHODS
  Eighty-four iNPH patients underwent shunt operations using MRI selection criteria from the SINPHONI and were subjected to CBF single photon emission computed tomography (SPECT). The perfusion patterns on SPECT were classified: anterior-dominant CBF reduction type (A type), posterior-dominant CBF reduction type (P type), and mixed or diffuse CBF reduction type (M type). The predictive value of the CBF pattern for favorable shunt outcome was evaluated.
  
  
  RESULTS
  Favorable outcomes were obtained in 76% (64/84) of patients, and shunt responsiveness was achieved in 85% (71/84) of patients. Areas of severely reduced relative CBF were demonstrated around the corpus callosum and in the sylvian fissure area, which included the effects of dilatations of the ventricles and sylvian fissures and relatively increased perfusion in the medial and lateral frontal, parietal, and occipital areas at high convexity. Forty-nine (58%) cases were A type, 25 (30%) cases were M type, and 10 (12%) cases were P type. A, M, and P type cases exhibited 83, 84, and 90% positive predictive values for shunt responsiveness, respectively. Mean modified Rankin scale and Mini-Mental State Examination scores of the A type group were significantly better than those of other groups.
  
  
  CONCLUSIONS
  The iNPH patients showed various patterns of CBF reduction, but there was no significant difference in the predictive value among the three patterns, though CBF reduction patterns may suggest a severe condition of iNPH.
authors.affiliation: Department of Radiology, Kinki University Faculty of Medicine, Osakasayama, Japan. kishii @ hbhc.jp
authors.forename: Kazunari
authors.initials: K
authors.lastname: Ishii
authors.forename: Masaaki
authors.initials: M
authors.lastname: Hashimoto
authors.forename: Kohei
authors.initials: K
authors.lastname: Hayashida
authors.forename: Kazuo
authors.initials: K
authors.lastname: Hashikawa
authors.forename: Chia-Cheng
authors.initials: CC
authors.lastname: Chang
authors.forename: Jyoji
authors.initials: J
authors.lastname: Nakagawara
authors.forename: Teiji
authors.initials: T
authors.lastname: Nakayama
authors.forename: Satoru
authors.initials: S
authors.lastname: Mori
authors.forename: Ryuji
authors.initials: R
authors.lastname: Sakakibara
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000662:Amphetamines; D020771:Anterior Cerebral Artery / Q000503:physiopathology; D001931:Brain Mapping; D002560:Cerebrovascular Circulation / Q000502:physiology; D005260:Female; D006801:Humans; D006850:Hydrocephalus, Normal Pressure / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000601:surgery; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D020769:Posterior Cerebral Artery / Q000503:physiopathology; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D018401:Sample Size; D015899:Tomography, Emission-Computed, Single-Photon; D016896:Treatment Outcome; D017287:Ventriculoperitoneal Shunt
chemical_list: D000662:Amphetamines; D019275:Radiopharmaceuticals; C041336:4-iodoamphetamine