ALARA: Impact of Practice Quality Improvement Initiative on Dose Reduction in Pediatric Voiding Cystourethrogram

This practice quality improvement study of pediatric voiding cystourethrogram (VCUG) investigated the adequacy of substituting last-image capture for digital-spot images and dose reduction when this substitution was implemented and determined correlations between dose-area products (DAPs), patient ages, and fluoroscopy times.

The study consisted of three phases: phase 1 documented baseline data and evaluated diagnostic accuracy between last-image capture and digital-spot images. Phase 2 documented the change in dose after substituting last-image capture for digital-spot images. Phase 3 measured doses 3 years later. Each phase-1 VCUG study was segregated into two image sets: last-image capture and digital-spot images. Three radiologists graded vesicoureteral reflux on each side using the international grading scale. Weighted kappa statistics assessed grading differences between image sets. Patient age, fluoroscopy time, and DAP were assessed with parametric and nonparametric statistics.

Seventy-seven, 65, and 71 VCUGs were assessed for phases 1, 2, and 3, respectively. Weighted κ = 0.94-0.99 indicated nearly perfect agreement between last-image-capture and digital-spot-image interpretations. For phase 2, last-image capture was substituted for digital-spot images for early-filling and voiding images. DAP decreased for all three radiologists (p ≤ 0.01). Five of six (83%) correlations between DAP and age were higher than the correlations between DAP and fluoroscopy time. The dose remained significantly lower in phase 3.

This project changed practice by substituting last-image capture for digital-spot images without affecting vesicoureteral reflux grading while reducing radiation exposure. Monitoring DAP is a better assessment of radiation exposure than is fluoroscopy time.