Comment on a prospective evaluation of computerized tomographic (CT) scanning as a screening modality for esophageal varices

Abstract

Comment on a Prospective Evaluation of Computerized Tomographic (CT) Scanning as a Screening Modality for Esophageal VaricesTo the Editor:We read with interest the article by Perri et al. published in a recent issue of HEPATOLOGY. 1 Perri et al. report that abdominal computed tomography (CT) performed as the initial screening test for esophageal varices could be cost-effective. The total effective radiation dose for CT was 15 mSv, slightly highly than that for an abdominal and pelvic CT scan. We know that the effective dose, expressed in sieverts, allows for a rough comparison between different CT scenarios but provides only an approximation of the true risk.According to a report by the U.S. National Academy of Sciences, a single population dose of 10 mSv is associated with a lifetime risk of a solid cancer or leukemia of 1 in 2000. 2 The radiation dose is particularly problematic when patients have multiple CT scans, as requested if no varices are identified by CT scan, because screening for varices should then be repeated in 2-3 years according to current recommendations.Although the individual estimates are small, the concern about the risks from CT is related to the rapid increase in its use, and it has been estimated that about 1.5%-2.0% of all cancers in the United States may be attributable to radiation from CT studies. 3 No largescale epidemiologic studies of the cancer risks associated with CT scans have been reported, but one such study is just beginning. 4 The most effective way to reduce the population dose from CT is simply to decrease the number of CT studies that are prescribed, especially if we have a simple and effective method such as gastroscopy.Perri et al. should at least acknowledge these concerns.

Towards Noninvasive Detection of Oesophageal Varices

“…How reproducible this model could, therefore, remain unproven. There are also major concerns over the risk of cumulative radiation exposure in prolonged screening programmes [ 67 ].…”