Area Editoriale
INTRODUCTION:Published studies have reported a wide range of sensitivities and specificitiesfor computed tomographic (CT) colonography for polyp detection, generatingcontroversy regarding its diagnostic accuracy. METHODS: A meta-analysis ofpublished studies comparing the accuracies of CT colonography and colonoscopyfor polyp detection was performed. The pooled per-patient sensitivities andspecificities were calculated at various thresholds for polyp size. Summaryreceiver operating characteristic (sROC) curves were also constructed. RESULTS:Thirty studies were included in the meta-analysis of CT colonography. Thepooled per-patient sensitivity of CT colonography was higher for polyps greaterthan 10 mm (0.82, 95% confidence interval [CI], 0.76-0.88) compared with polyps6 to 10 mm (0.63, 95% CI, 0.52-0.75) and polyps 0 to 5 mm (0.56, 95% CI,0.42-0.70). Similarly, the exact area under the sROC curve (area +/- standarderror) was higher using a threshold greater than 10 mm (0.898 +/- 0.063)compared with thresholds of greater than 5 mm and any size (0.884 +/- 0.033 and0.822 +/- 0.059, respectively). There were no significant differences in thediagnostic characteristics of 2-dimensional versus 3-dimensional CTcolonography. At a threshold greater than 5 mm, the exact area under the sROCcurve was significantly higher for endoscopic colonoscopy compared with CTcolonography (0.998 +/- 0.006 vs 0.884 +/- 0.033, P < .005). CONCLUSIONS: CTcolonography has a reasonable sensitivity and specificity for detecting largepolyps but was less accurate than endoscopic colonoscopy for smaller polyps.Thus, CT colonography may not be a reasonable alternative in situations inwhich a small polyp may be clinically relevant.Leggil'articolo