title: New computer-aided diagnosis of dementia using positron emission tomography: brain regional sensitivity-mapping method.
abstract: OBJECTIVE
  We devised a new computer-aided diagnosis method to segregate dementia using one estimated index (Total Z score) derived from the Brodmann area (BA) sensitivity map on the stereotaxic brain atlas. The purpose of this study is to investigate its accuracy to differentiate patients with Alzheimer's disease (AD) or mild cognitive impairment (MCI) from normal adults (NL).
  
  
  METHODS
  We studied 101 adults (NL: 40, AD: 37, MCI: 24) who underwent (18)FDG positron emission tomography (PET) measurement. We divided NL and AD groups into two categories: a training group with (Category A) and a test group without (Category B) clinical information. In Category A, we estimated sensitivity by comparing the standard uptake value per BA (SUVR) between NL and AD groups. Then, we calculated a summated index (Total Z score) by utilizing the sensitivity-distribution maps and each BA z-score to segregate AD patterns. To confirm the validity of this method, we examined the accuracy in Category B. Finally, we applied this method to MCI patients.
  
  
  RESULTS
  In Category A, we found that the sensitivity and specificity of differentiation between NL and AD were all 100%. In Category B, those were 100% and 95%, respectively. Furthermore, we found this method attained 88% to differentiate AD-converters from non-converters in MCI group.
  
  
  CONCLUSIONS
  The present automated computer-aided evaluation method based on a single estimated index provided good accuracy for differential diagnosis of AD and MCI. This good differentiation power suggests its usefulness not only for dementia diagnosis but also in a longitudinal study.
authors.affiliation: PET Medical Application Group, Central Research Laboratory, Hamamatsu Photonics K.K., Branch 5000, Hamamatsu, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Kakimoto
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Kamekawa
authors.forename: Shigeru
authors.initials: S
authors.lastname: Ito
authors.forename: Etsuji
authors.initials: E
authors.lastname: Yoshikawa
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Okada
authors.forename: Sadahiko
authors.initials: S
authors.lastname: Nishizawa
authors.forename: Satoshi
authors.initials: S
authors.lastname: Minoshima
authors.forename: Yasuomi
authors.initials: Y
authors.lastname: Ouchi
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000175:diagnosis*; D019540:Area Under Curve; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping / Q000379:methods*; D060825:Cognitive Dysfunction / Q000175:diagnosis; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008137:Longitudinal Studies; D008297:Male; D008609:Mental Status Schedule; D008875:Middle Aged; D015233:Models, Statistical; D049268:Positron-Emission Tomography / Q000379:methods*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012984:Software