Endoscopy 2002; 34(6): 441-446
DOI: 10.1055/s-2002-31999
Original Article

© Georg Thieme Verlag Stuttgart · New York

Computed Tomographic Colonography (Virtual Colonoscopy): Blinded Prospective Comparison with Conventional Colonoscopy for the Detection of Colorectal Neoplasia

A.  Laghi 1 , R.  Iannaccone 1 , I.  Carbone 1 , C.  Catalano 1 , V.  Panebianco 1 , E.  Di Giulio 2 , A.  Schillaci 2 , R.  Passariello 1
  • 1 Department of Radiology II, University of Rome - La Sapienza, Policlinico Umberto I, Rome, Italy
  • 2 Department of Surgery, University of Rome - La Sapienza, Policlinico Umberto I, Rome, Italy
Further Information

Publication History

30 April 2001

21 November 2001

Publication Date:
04 June 2002 (online)

Background and Study Aims: Computed tomographic colonography (CTC), also known as virtual colonoscopy, is a recently introduced imaging modality for the detection of colorectal neoplasia. The aim of our study was to evaluate the performance of CTC in a blinded comparison with conventional colonoscopy.
Patients and Methods: A total of 66 consecutive, symptomatic patients underwent spiral computed tomography (CT) examination after standard bowel preparation. CT images were analyzed and subsequently compared with conventional colonoscopy findings.

Results: Conventional colonoscopy detected 15 colorectal carcinomas and 52 polyps. CTC correctly identified all carcinomas, 13 of 14 polyps greater than 10.0 mm (sensitivity 92.8 %; 95 % confidence interval (95 % CI); 77 - 100), 11 of 13 polyps between 6.0 and 9.0 mm (sensitivity 84.6 %; 95 % CI; 62 - 100), and six of 25 polyps smaller than 5.0 mm (sensitivity 24 %; 95 % CI; 6 - 42). The per-patient sensitivity and specificity were 93.7 % and 94.1 %, respectively.

Conclusions: Computed tomographic colonography is an accurate imaging modality for the detection of colorectal neoplasia, especially for lesions larger than 6.0 mm in diameter.

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Dr. A. Laghi

Department of Radiology II, University of Rome - La Sapienza, Policlinico Umberto I

Via Salaria 334 · 00199 Rome · Italy

Fax: + 39-06-490243

Email: andrea.laghi@uniroma1.it

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