Comparison of the relative sensitivity of CT colonography and double-contrast barium enema for screen detection of colorectal polyps

Clin Gastroenterol Hepatol. 2004 Apr;2(4):314-21. doi: 10.1016/s1542-3565(04)00061-8.


Background & aims: In a population reflective of a screening setting, our aim was to compare the relative sensitivity and specificity of computed tomography (CT) colonography with double-contrast barium enema (DCBE) for detection of colorectal polyps and to assess the added value of double reading at CT colonography, using endoscopy as the arbiter.

Methods: This prospective, blinded study comprised 837 asymptomatic persons at higher than average risk for colorectal cancer who underwent CT colonography followed by same-day DCBE. Examinations with polyps > or =5 mm in diameter were referred to colonoscopy.

Results: CT colonography readers detected 56%-79% of polyps > or =10 mm in diameter. In comparison, the sensitivity at DCBE varied between 39% and 56% for the 31 polyps > or =1 cm. All of the readers detected more polyps at CT colonography than DCBE, but the difference was statistically significant for only a single reader (P = 0.02). Relative specificity for polyps > or =10 mm on a per-patient basis ranged from 96% to 99% at CT colonography, and 99%-100% at DCBE. Doubly read CT colonography detected significantly more polyps than DCBE (81% vs. 45% for polyps > or =1 cm [P = <0.01], and 72% vs. 44% for polyps 5-9 mm [P < or = 0.01]).

Conclusions: Double-read CT colonography is significantly more sensitive in detecting polyps than single-read double contrast barium enema. DCBE was significantly more specific than CT colonography.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Barium Sulfate*
  • Colonic Polyps / diagnostic imaging*
  • Colonic Polyps / pathology
  • Colonography, Computed Tomographic / methods*
  • Colonoscopy / methods
  • Colorectal Neoplasms / diagnostic imaging*
  • Colorectal Neoplasms / pathology
  • Enema*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Observer Variation
  • Probability
  • Prospective Studies
  • Risk Assessment
  • Sensitivity and Specificity
  • Single-Blind Method
  • Therapeutic Irrigation / methods


  • Barium Sulfate