Radiation From Kidney-Ureter-Bladder Radiographs Is Not Trivial

Urology. 2019 Mar:125:46-49. doi: 10.1016/j.urology.2018.11.035. Epub 2018 Dec 4.

Abstract

Objective: To estimate effective dose of kidney-ureter-bladder (KUB) radiographs in a contemporary population of patients with urolithiasis.

Methods: A retrospective review was performed to identify patients visiting a urology clinic for urolithiasis where a KUB was obtained and whom had a recent computed tomography (CT). Effective dose for KUBs was estimated using a Monte Carlo based simulation program and for CT utilizing the reported dose-length-product. Age, gender, body mass index, and abdominal diameter were analyzed for association with effective dose. KUBs performed at outside facilities in referred patient were compared to those obtained locally when available.

Results: Fifty-four patients were identified meeting criteria. The majority (92.6%) of KUBs contained multiple radiographs. Mean effective dose was 2.15 mSv ± 1.67 mSv. Only 26% of examinations effective dose was under 1 mSv. Body mass index, abdominal thickness, and image count were all associated with an increase in dose (P < .01 each). Similar to local KUBs, 88% of outside examinations contained multiple images.

Conclusion: KUB examinations in this contemporary setting are associated with a 2-fold higher effective dose then is often referenced. Increased effective dose is associated with increased patient size and number of images acquired. Nearly 1 in 5 patient's KUB effective dose was similar to a low-dose CT. KUBs role should be re-examined given its limited sensitivity, specificity, associated radiation, and other available imaging options.

MeSH terms

  • Female
  • Humans
  • Kidney / diagnostic imaging*
  • Male
  • Middle Aged
  • Radiation Dosage*
  • Radiation Exposure / statistics & numerical data*
  • Retrospective Studies
  • Tomography, X-Ray Computed*
  • Ureter / diagnostic imaging*
  • Urinary Bladder / diagnostic imaging*
  • Urolithiasis / diagnostic imaging*