title: Tc-99m ethylcysteinate dimer SPECT in the differential diagnosis of dementias.
abstract: BACKGROUND
  Dementias produce deficits in perfusion, in part, reflecting decreased metabolic needs. Single photon emission computed tomography (SPECT) studies have reported characteristic anterior-to-posterior perfusion gradients that permit distinction between the various forms of dementia.
  
  
  OBJECTIVE
  We undertook this study to evaluate the role of visual analysis of SPECT perfusion patterns for the differential diagnosis of types of degenerative dementia.
  
  
  METHODS
  Tc-99m ethylcysteinate dimer (ECD) was used with a dual-head scanner to generate perfusion images of the brain in 136 patients referred from the dementia clinic. Diagnosis was made by the nuclear physician unaware of clinical diagnosis.
  
  
  RESULTS
  Sensitivity, specificity, positive predictive value and negative predictive value of perfusion studies for Alzheimer's dementia were 93.42%, 95.12%, 97.26%, and 88.63%, respectively, and for frontotemporal dementia were 96.29%, 98%, 96.29%, and 98.88%, respectively.
  
  
  CONCLUSIONS
  Tc-99m ECD brain perfusion SPECT is useful in the differential diagnosis of dementia with particular reference to AD as well as FTD.
authors.affiliation: Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India. madhu_deven@yahoo.com
authors.forename: Madhavi
authors.initials: M
authors.lastname: Tripathi
authors.forename: Manjari
authors.initials: M
authors.lastname: Tripathi
authors.forename: Deepti
authors.initials: D
authors.lastname: Vibha
authors.forename: Naveen
authors.initials: N
authors.lastname: Gowda
authors.forename: Chandrashekhar
authors.initials: C
authors.lastname: Bal
authors.forename: Arun
authors.initials: A
authors.lastname: Malhotra
mesh_terms: D000368:Aged; D003545:Cysteine / Q000031:analogs & derivatives*; D003704:Dementia / Q000145:classification / Q000000981:diagnostic imaging*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015609:Organotechnetium Compounds; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
chemical_list: D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C059659:technetium Tc 99m bicisate; D003545:Cysteine