Diagnostic Ionizing Radiation Exposure in a Population-Based Cohort of Patients with Inflammatory Bowel Disease

Abstract

Objective-For diagnosis, assessing disease activity, complications and extraintestinal manifestations, and monitoring response to therapy, patients with inflammatory bowel disease undergo many radiological studies employing ionizing radiation. However, the extent of radiation exposure in these patients is unknown.Methods-A population-based inception cohort of 215 patients with inflammatory bowel disease from Olmsted County, Minnesota, diagnosed between 1990 and 2001, was identified. The total effective dose of diagnostic ionizing radiation was estimated for each patient. Linear regression was used to assess the median total effective dose since symptom onset.Results-The number of patients with Crohn's disease and ulcerative colitis was 103 and 112, with a mean age at diagnosis of 38.6 and 39.4 yr, respectively. Mean follow-up was 8.9 yr for Crohn's disease and 9.0 yr for ulcerative colitis. Median total effective dose for Crohn's disease was 26.6 millisieverts (mSv) (range, 0-279) versus 10.5 mSv (range, 0-251) for ulcerative colitis (P < 0.001). Computed tomography accounted for 51% and 40% of total effective dose, respectively. Patients with Crohn's disease had 2.46 times higher total effective dose than ulcerative colitis patients (P = 0.001), adjusting for duration of disease.Conclusions-Annualizing our data, the radiation exposure in the inflammatory bowel disease population was equivalent to the average annual background radiation dose from naturally occurring sources in the U.S. (3.0 mSv). However, a subset of patients had substantially higher doses. The development of imaging management guidelines to minimize radiation dose, dosereduction techniques in computed tomography, and faster, more robust magnetic resonance techniques are warranted.

221 Psychiatric Co-Morbidity Is Associated With Increased Risk of Surgery in Crohns Disease

“…Also concerning is our finding of the independent effect of psychiatric co-morbidity on undergoing abdominal imaging studies, primarily CT scans. We were not able to ascertain whether the imaging studies obtained were appropriate, but several recent studies have highlighted the high frequency of radiographic studies in CD patients [41][42][43] . Thus, it is important for treating physicians to recognize underlying psychiatric co-morbidity could be a potential risk factor for multiple radiologic studies, to practice judicious use of imaging studies and use alternate imaging modalities such as magnetic resonance imaging (MRI) studies wherever indicated and possible in such patients.…”

The Role of Imaging in Inflammatory Bowel Disease Evaluation

“…For this reason, the concept of "effective dose" was introduced. This term, measured in millisieverts (mSv), reflects an attempt to create a standard metric that quantifies the impact of the absorbed radiation (Peloquin et al, 2008). Effective dose is calculated by multiplying the absorbed radiation dose by a conversion factor for the body segment that was imaged; this conversion factor varies based upon the radiosensitivity of the exposed organs.…”

Predicting the Need for Imaging in IBD: Radiating Only Badness?

“…Multiple retrospective studies have reported radiation exposures in CD patients to be higher than that of the general population [7,8]. The use of CT in patients with inflammatory bowel disease (IBD) has increased noticeably in the last decade with an 840 % increase from 2003 to 2007 reported at one institution [9]. A retrospective cohort study of 415 patients over 20 years found that usage of CTs increased by 310 % and that 1 in 13 patients was exposed to potentially harmful levels of ionizing radiation defined as CED [50 mSv.…”