Clinical Audit of Radiation Dose Reduction in Micturating Cystourethrogram: an Initiative for Patient Safety and Quality Improvement

Full Article

KYA Au, WCW Wong, LSJ Khoo

Hong Kong J Radiol 2016;19:170-82

DOI: 10.12809/hkjr1615384

Objectives: To ensure that the radiation dose from micturating cystourethrograms (MCUs) performed in our centre is regularly and constantly reviewed, and to identify ways in which radiation dose can be reduced and maintained in line with international standards.

Methods: This was a clinical audit of the radiation dose and fluoroscopic screening time of MCU examination performed in 97 patients between April 2013 and June 2015 at a tertiary referral centre in Hong Kong before and after implementation of radiation reduction measures. Along with the general measures to reduce radiation dose, the three major measures taken were (1) minimising fluoroscopic screening time during the early-to-intermediate bladder filling phases during which time only limited diagnostic information was obtained; (2) bilateral fluoroscopic screening of the urinary tract in one voiding cycle to detect reflux, thus avoiding the need for two voiding cycles; and (3) using a mathematical formula to estimate the time when urinary bladder capacity was reached and the child might start to void. Statistical analysis was performed of dose area product (DAP) and fluoroscopic screening time during the MCU and compared with the diagnostic reference level (DRL) set by the UK’s National Radiological Protection Board.

Results: The mean DAP of MCUs in our hospital before and after implementation of dose reduction measures was 49.3 uGym2 and 38.1 uGym2, respectively, with a statistically significant reduction in DAP of 22.7% (p = 0.036). A similar reduction of 20.6% was also observed in the fluoroscopic screening time that reduced from a mean of 115.3 seconds before to 91.6 seconds after dose reduction measures (p = 0.002). Overall, a reduction in radiation dose from our MCU examinations from 20.2% above the DRL to below the third quartile was observed.

Conclusion: A statistically significant 22.7% reduction in radiation dose from MCU examinations was achieved after the implementation of dose reduction measures in our hospital. This has also resulted in a mean radiation dose that is below the third quartile of the DRL of the UK's dose reference level.









結果:本院在減少輻射劑量措施實施前後的DAP分別為49.3 uGym2和38.1 uGym2;下降幅度為22.7%,並統計顯著(p=0.036)。暴露在X光射源下的時間則由方法實施前的115.3秒減至實施後的91.6秒;下降幅度為20.6%(p=0.002)。總的來說,MCU檢測中輻射劑量的減少從實施前在英國DRL之上的20.2%減至實施後DRL第三四分位數以下。