title: Gallbladder nonvisualization with pericholecystic rim sign: morphine-augmentation optimizes diagnosis of acute cholecystitis.
abstract: This study investigated the value of morphine-augmentation in patients who demonstrated gallbladder nonvisualization with a pericholecystic rim sign at 1 hr, a cholescintigraphic pattern considered highly predictive of acute cholecystitis.
  
  
  METHODS
  Retrospectively, 170 consecutive morphine-augmented cholescintigrams were analyzed for the presence of a pericholecystic rim sign, marked or mild, associated with gallbladder nonvisualization at 1 hr (before morphine); those with a pericholecystic rim sign were further evaluated for persistent gallbladder nonvisualization versus gallbladder visualization after morphine. Scintigraphic interpretations were correlated with surgical pathology or clinical diagnosis.
  
  
  RESULTS
  Before morphine, 43/170 (25%) patients demonstrated gallbladder nonvisualization with a pericholecystic rim sign. Since only 31 had acute cholecystitis, a diagnosis based solely on that scintigraphic pattern would have resulted in 12 false-positives. After morphine, gallbladder visualization correctly excluded acute cholecystitis in seven; a single false-negative was encountered; five false-positives remained. Morphine-augmentation improved the positive predictive value from 72% (gallbladder nonvisualization with pericholecystic rim sign before morphine) to 86% (gallbladder nonvisualization after morphine). Of 24 patients with marked pericholecystic rim signs, 21 had acute cholecystitis. Of 31 with acute cholecystitis, however, 10 (32%) had a mild pericholecystic rim sign.
  
  
  CONCLUSIONS
  Morphine-augmented cholescintigraphy optimizes the diagnosis of acute cholecystitis in patients with the suggestive, but not pathognomonic, cholescintigraphic pattern at 1 hr of gallbladder nonvisualization with a pericholecystic rim sign, regardless of its intensity.
authors.affiliation: Department of Radiology, New England Medical Center, Boston, MA 02111, USA.
authors.forename: E
authors.initials: E
authors.lastname: Oates
authors.forename: D L
authors.initials: DL
authors.lastname: Selland
authors.forename: C T
authors.initials: CT
authors.lastname: Chin
authors.forename: D M
authors.initials: DM
authors.lastname: Achong
mesh_terms: D000208:Acute Disease; D000814:Aniline Compounds; D016022:Case-Control Studies; D002764:Cholecystitis / Q000000981:diagnostic imaging*; D002908:Chronic Disease; D005189:False Positive Reactions; D005260:Female; D005704:Gallbladder / Q000000981:diagnostic imaging*; D005998:Glycine; D006801:Humans; D007098:Imino Acids; D008099:Liver / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D009020:Morphine; D015609:Organotechnetium Compounds; D011237:Predictive Value of Tests; D011877:Radionuclide Imaging; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D000814:Aniline Compounds; D007098:Imino Acids; D015609:Organotechnetium Compounds; D009020:Morphine; C034837:technetium Tc 99m mebrofenin; D005998:Glycine