title: Frontotemporal decreases in rCBF correlate with degree of dysnomia in primary progressive aphasia.
abstract: Primary progressive aphasia (PPA) is an uncommon degenerative dementia characterized by gradual impairment of language function with initial sparing of the memory domain. Using semiquantitative 99mTc-hexamethyl propyleneamine oxime (HMPAO) brain SPECT as a measure of regional cerebral blood flow (rCBF), we investigated the relationship between reduced 99mTc-HMPAO uptake and the severity of dysnomia in PPA.
  
  
  METHODS
  Seven right-handed patients with PPA had their dysnomia assessed by the Boston Naming Test (BNT), a subtest of the Boston Diagnostic Aphasia Examination. Neuroimaging studies, including 99mTc-HMPAO brain SPECT, CT, and MRI, were performed. Correlational analysis between reduced rCBF and BNT was performed.
  
  
  RESULTS
  Brain SPECT showed a reduction in 99mTc-HMPAO uptake involving the frontal and temporal lobes in all 7 patients. CT and MRI showed mild to moderate cerebral atrophy in 4 patients. Low scores on the BNT correlated with low frontotemporal 99mTc-HMPAO (Spearman r = 0.97, P = 0.004) in the 5 patients with left-hemisphere involvement.
  
  
  CONCLUSIONS
  Decreased rCBF to the frontotemporal region characterized the cerebral abnormalities associated with PPA. The finding of focal rCBF abnormalities in the right hemisphere of 2 right-handed women corroborates that PPA symptoms may arise from a "non-left-dominant"-hemisphere degenerative process. Our results support the usefulness of rCBF SPECT imaging as a diagnostic aid in PPA.
authors.affiliation: Department of Radiology, University of Alabama at Birmingham Medical Center, 35233-6835, USA.
authors.forename: E C
authors.initials: EC
authors.lastname: San Pedro
authors.forename: G
authors.initials: G
authors.lastname: Deutsch
authors.forename: H G
authors.initials: HG
authors.lastname: Liu
authors.forename: J M
authors.initials: JM
authors.lastname: Mountz
mesh_terms: D000368:Aged; D000849:Anomia / Q000000981:diagnostic imaging* / Q000503:physiopathology; D018888:Aphasia, Primary Progressive / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D019275:Radiopharmaceuticals; D019690:Technetium Tc 99m Exametazime; D013702:Temporal Lobe / Q000000981:diagnostic imaging*; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D019275:Radiopharmaceuticals; D019690:Technetium Tc 99m Exametazime