Letters Section Editor: Robert M. Golub,
MD, Senior Editor.
To the Editor: Dr Cotton and colleagues1 reported that computed tomographic colonography
(CTC), also known as virtual colonoscopy, had much lower sensitivity for detecting
colonic neoplasms than did conventional colonoscopy. We have several concerns
about the authors' methods.
First, their technology appears to be outdated. Some of the 9 institutions
in the study used thick CT slice collimation (5 mm). This contrasts the current
practice standard of 3 mm or less. Thicker slices may degrade anatomic detail,
especially of small polyps. Furthermore, the authors did not describe their
visualization software. Since their study was conducted between April 17,
2000, and October 3, 2001, the software was likely outdated compared with
that currently available.
Ferrucci J, Barish M, Choi R, Dachman A, Fenlon H, Glick S, Laghi A, Macari M, Morrin M, Paulson E, Pickhardt PJ, Soto J, Yee J, Zalis M. Virtual Colonoscopy. JAMA. 2004;292(4):431-433. doi:10.1001/jama.292.4.431-b