Computer-aided detection for computed tomographic colonography screening: A prospective comparison of a double-reading paradigm with first-reader computer-aided detection against second-reader computer-aided detection

Gabriella Iussich, Loredana Correale, Carlo Senore, Cesare Hassan, Nereo Segnan, Delia Campanella, Alberto Bert, Giovanni Galatola, Cristiana Laudi, Daniele Regge

Research output: Contribution to journalArticle


OBJECTIVES: The objective of this study was to prospectively compare diagnostic performance and time efficiency of a double-reading paradigm in which a first-reader computer-aided detection (CAD) is followed by a fast 2-dimensional review (DR FR-CAD) with those of a double reading with second-reader CAD (SR CAD). MATERIALS AND METHODS: The local ethical committee approved this study. Consecutive immunological patients who have positive results for fecal immunological test who were scheduled for colonoscopy were enrolled for a 10-month period. Computed tomographic colonography studies were read with CAD (CAD COLON-1.20; im3D, Turin, Italy) by using both SR CAD (applied after unassisted interpretation primary 2-dimensional) and DR FR-CAD (CAD-prompts evaluation followed by a fast 2-dimensional review) in randomized order with the radiologist for each reading paradigm masked to the other reader's results.Per-patient sensitivity and specificity of unassisted and CAD-assisted readings for detecting 6-mm adenomas or larger were calculated by using unblinding colonoscopy as reference standard. Reporting times were also calculated. Pairwise comparisons were performed. RESULTS: A total of 182 participants (median age, 65 years; range, 58-76) were included in the final analysis. Of these, 93 (51%) had at least 1 cancer or a 6-mm adenoma or larger. At the 6-mm threshold, sensitivity of unassisted reading (79.6%; 95% confidence interval [CI], 69.9-87.2) increased significantly with the use of both SR CAD (86.0%; 95% CI, 77.3%-92.3%) and DR FR-CAD (89.2%; 95% CI, 81.1%-94.7%), without differences between CAD readings (P = 0.500). No significant differences in specificity among the 3 paradigms were observed. Double reading with first-reader CAD required less reading time than that for SR CAD (378 vs 496; Δ118 seconds; P <0.001) and was 59 seconds longer than the unassisted reading (P = 0.058). CONCLUSIONS: When compared with unassisted reading, a double-reading paradigm in which first-reader CAD is followed by a fast 2-dimensional review improves the adenoma detection rate to the same level achieved by a second-reader CAD while decreasing reporting times.

Original languageEnglish
Pages (from-to)173-182
Number of pages10
JournalInvestigative Radiology
Issue number3
Publication statusPublished - Mar 2014



  • adenomas
  • colon-rectal cancer
  • computer-aided detection
  • CT colonography
  • screening

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging

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