title: Semiquantitative measurement of pulmonary hilar gallium-67 uptake using single photon emission computed tomography/computed tomography for the diagnosis of autoimmune pancreatitis.
abstract: OBJECTIVE
  We ascertained the difference in the level of pulmonary hilar (PH) gallium-67 (Ga-67) uptake in autoimmune pancreatitis (AIP) patients between the active (before corticosteroid therapy) and remittent (after 4 weeks of corticosteroid therapy) phases using a semiquantitative measurement method based on single photon emission computed tomography (SPECT) with integrated low-dose computed tomography (CT).
  
  
  METHODS
  Ga-67 planar scans and SPECT were performed in 11 AIP patients before and after 4 weeks of corticosteroid therapy. A region of interest (ROI) was drawn over the bilateral pulmonary hilum and the liver, and average counts of the pulmonary hilum and liver were calculated. The average counts of the pulmonary hilum divided by those of the liver gave the pulmonary hilum/liver ratio (H/L).
  
  
  RESULTS
  A significant difference was observed in the H/L between active and remittent phases. H/L in the active phase was 1.03±0.32 and that in the remittent phase was 0.58±0.25 (t-test, P=0.0016).
  
  
  CONCLUSIONS
  PH Ga-67 uptake in patients with active AIP was semiquantitatively higher than that in those with remittent AIP. Hence, this may be a useful finding for an early diagnosis, estimating the effectiveness of corticosteroid therapy, and following up patients with this disease.
authors.affiliation: Department of Radiology, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621, Japan. momosemi@shinshu-u.ac.jp
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Momose
authors.forename: Masumi
authors.initials: M
authors.lastname: Kadoya
authors.forename: Kesato
authors.initials: K
authors.lastname: Yano
authors.forename: Tadashi
authors.initials: T
authors.lastname: Miyasaka
authors.forename: Yasunari
authors.initials: Y
authors.lastname: Fujinaga
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Matsushita
authors.forename: Shin
authors.initials: S
authors.lastname: Yanagisawa
authors.forename: Hideaki
authors.initials: H
authors.lastname: Hamano
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Kawa
mesh_terms: D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D005710:Gallium Radioisotopes; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008099:Liver / Q000000981:diagnostic imaging; D008168:Lung / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D010195:Pancreatitis / Q000000981:diagnostic imaging* / Q000188:drug therapy; D019275:Radiopharmaceuticals; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D000305:Adrenal Cortex Hormones; D005710:Gallium Radioisotopes; D019275:Radiopharmaceuticals