title: A new technique for the diagnosis of acute appendicitis: abdominal CT with compression to the right lower quadrant.
abstract: OBJECTIVE
  To determine the diagnostic accuracy of abdominal CT with compression to the right lower quadrant (RLQ) in adults with acute appendicitis.
  
  
  METHODS
  168 patients (age range, 18-78 years) were included who underwent contrast-enhanced CT for suspected appendicitis performed either using compression to the RLQ (n = 71) or a standard protocol (n = 97). Outer diameter of the appendix, appendiceal wall thickening, luminal content and associated findings were evaluated in each patient. Kruskal-Wallis, Fisher's and Pearson's chi-squared tests were used for statistical analysis.
  
  
  RESULTS
  There was no significant difference in the mean outer diameter (MOD) between compression CT scans (10.6 ± 1.9 mm) and standard protocol (11.2 ± 2.3 mm) in patients with acute appendicitis (P = 1). MOD was significantly lower in the compression group (5.2 ± 0.8 mm) compared to the standard protocol (6.5 ± 1.1 mm) (P < 0.01) in patients without appendicitis. A cut-off value of 6.75 mm for the outer diameter of the appendix was found to be 100% sensitive in the diagnosis of acute appendicitis for both groups. The specificity was higher for compression CT technique (67.7 vs. 94.9%).
  
  
  CONCLUSIONS
  Normal appendix diameter was significantly smaller in the compression-CT group compared to standard-CT group, increasing diagnostic accuracy of abdominal compression CT.
  
  
  CONCLUSIONS
  • Normal appendix diameter is significantly smaller in compression CT. • Compression could force contrast material to flow through the appendiceal lumen. • Compression CT may be a CT counterpart of graded compression US.
authors.affiliation: Department of Radiology, Hacettepe University Faculty of Medicine, Sıhhiye, Ankara, 06100, Turkey.
authors.forename: Abidin
authors.initials: A
authors.lastname: Kılınçer
authors.affiliation: Department of Radiology, Hacettepe University Faculty of Medicine, Sıhhiye, Ankara, 06100, Turkey. erhan.akpinar@gmail.com.
authors.forename: Erhan
authors.initials: E
authors.lastname: Akpınar
authors.affiliation: Department of Emergency Medicine, Hacettepe University Faculty of Medicine, Ankara, Turkey.
authors.forename: Bülent
authors.initials: B
authors.lastname: Erbil
authors.affiliation: Department of Radiology, Hacettepe University Faculty of Medicine, Sıhhiye, Ankara, 06100, Turkey.
authors.forename: Emre
authors.initials: E
authors.lastname: Ünal
authors.affiliation: Department of Radiology, Hacettepe University Faculty of Medicine, Sıhhiye, Ankara, 06100, Turkey.
authors.forename: Ali Devrim
authors.initials: AD
authors.lastname: Karaosmanoğlu
authors.affiliation: Department of General Surgery, Hacettepe University Faculty of Medicine, Ankara, Turkey.
authors.forename: Volkan
authors.initials: V
authors.lastname: Kaynaroğlu
authors.affiliation: Department of Radiology, Hacettepe University Faculty of Medicine, Sıhhiye, Ankara, 06100, Turkey.
authors.forename: Deniz
authors.initials: D
authors.lastname: Akata
authors.affiliation: Department of Radiology, Hacettepe University Faculty of Medicine, Sıhhiye, Ankara, 06100, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Özmen
mesh_terms: D000005:Abdomen; D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D001064:Appendicitis / Q000000981:diagnostic imaging* / Q000473:pathology; D001065:Appendix / Q000000981:diagnostic imaging / Q000473:pathology; D016009:Chi-Square Distribution; D003287:Contrast Media; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D011312:Pressure; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult
chemical_list: D003287:Contrast Media
keywords: Abdominal CT; Acute appendicitis; Adults; Compression; Right lower quadrant