title: Improved Diagnostic Accuracy of SPECT Through Statistical Analysis and the Detection of Hot Spots at the Primary Sensorimotor Area for the Diagnosis of Alzheimer Disease in a Community-Based Study: "The Osaki-Tajiri Project".
abstract: OBJECTIVE
  SPECT is an important diagnostic tool for dementia. Recently, statistical analysis of SPECT has been commonly used for dementia research. In this study, we evaluated the accuracy of visual SPECT evaluation and/or statistical analysis for the diagnosis (Dx) of Alzheimer disease (AD) and other forms of dementia in our community-based study "The Osaki-Tajiri Project."
  
  
  METHODS
  Eighty-nine consecutive outpatients with dementia were enrolled and underwent brain perfusion SPECT with 99mTc-ECD. Diagnostic accuracy of SPECT was tested using 3 methods: visual inspection (SPECT Dx), automated diagnostic tool using statistical analysis with easy Z-score imaging system (eZIS Dx), and visual inspection plus eZIS (integrated Dx).
  
  
  RESULTS
  Integrated Dx showed the highest sensitivity, specificity, and accuracy, whereas eZIS was the second most accurate method. We also observed that a higher than expected rate of SPECT images indicated false-negative cases of AD. Among these, 50% showed hypofrontality and were diagnosed as frontotemporal lobar degeneration. These cases typically showed regional "hot spots" in the primary sensorimotor cortex (ie, a sensorimotor hot spot sign), which we determined were associated with AD rather than frontotemporal lobar degeneration.
  
  
  CONCLUSIONS
  We concluded that the diagnostic abilities were improved by the integrated use of visual assessment and statistical analysis. In addition, the detection of a sensorimotor hot spot sign was useful to detect AD when hypofrontality is present and improved the ability to properly diagnose AD.
authors.affiliation: From the *Division of Geriatric Behavioral Neurology, Cyclotron and Radioisotope Center, Tohoku University, Sendai, Japan; †Osaki-Tajiri SKIP Center, Osaki, Japan; and ‡Department of Radiology, Osaki City Hospital, Osaki, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Kaneta
authors.forename: Masahiro
authors.initials: M
authors.lastname: Nakatsuka
authors.forename: Kei
authors.initials: K
authors.lastname: Nakamura
authors.forename: Takashi
authors.initials: T
authors.lastname: Seki
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yamaguchi
authors.forename: Masahiro
authors.initials: M
authors.lastname: Tsuboi
authors.forename: Kenichi
authors.initials: K
authors.lastname: Meguro
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D012111:Residence Characteristics; D012680:Sensitivity and Specificity; D066191:Sensorimotor Cortex / Q000000981:diagnostic imaging; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods