Prospective Measurement of Patient Exposure to Radiation During Pediatric Ureteroscopy

Abstract

Objective Little data have been reported regarding radiation exposure during pediatric endourologic procedures, including ureteroscopy (URS). We sought to measure radiation exposure during pediatric URS and identify opportunities for exposure reduction. Methods We prospectively observed URS procedures as part of a quality improvement initiative. Pre-operative patient characteristics, operative factors, fluoroscopy settings and radiation exposure were recorded. Our outcomes were entrance skin dose (ESD, in mGy) and midline dose (MLD, in mGy). Specific modifiable factors were identified as targets for potential quality improvement. Results Direct observation was performed on 56 consecutive URS procedures. Mean patient age was 14.8 ± 3.8 years (range 7.4 to 19.2); 9 children were under age 12 years. Mean ESD was 46.4 ± 48 mGy. Mean MLD was 6.2 ± 5.0 mGy. The most important major determinant of radiation dose was total fluoroscopy time (mean 2.68 ± 1.8 min) followed by dose rate setting, child anterior-posterior (AP) diameter, and source to skin distance (all p<0.01). The analysis of factors affecting exposure levels found that the use of ureteral access sheaths (p=0.01) and retrograde pyelography (p=0.04) were significantly associated with fluoroscopy time. We also found that dose rate settings were higher than recommended in up to 43% of cases and ideal C-arm positioning could have reduced exposure 14% (up to 49% in some cases). Conclusions Children receive biologically significant radiation doses during URS procedures. Several modifiable factors contribute to dose and could be targeted in efforts to implement dose reduction strategies.

Retrograde intrarenal surgery for the treatment of renal stones: is fluoroscopy-free technique achievable?

“…According to a study of pediatric URS, the use of UAS was significantly associated with the duration of fluoroscopy [21]. Fluoroscopy can monitor the whole process of insertion of a UAS, which is helpful to avoid perforation of the renal pelvis resulting from deep insertion.…”

Prospective Systematic Intervention to Reduce Patient Exposure to Radiation During Pediatric Ureteroscopy

“…The specifics of data collection methods have been described in detail previously. 5 In short, a trained research assistant was present for each ureteroscopic procedure in its entirety, and collected data on patient characteristics, operative factors, fluoroscopy settings and radiation exposure.…”

“…The same criterion were used for inclusion/exclusion as in the prior report (limiting to patients <21 years old undergoing unilateral ureteroscopy for urolithiasis). 5 Distinct from the pre-checklist procedures, surgeons and operating room staff were informed about the checklist components and the primary project aims.…”

“…Multivariable linear regression was used to control for potential confounding when sufficient data points per outcome group were available. For the outcome of fluoroscopy time, items that were identified as potential predictors (p≤0.1) in our prior publication 5 were included in multivariable analyses. Log-transformation was performed on skin entrance dose and DAP outcomes to allow for parametric analysis.…”

“…5 Among the major determinants of radiation exposure, total fluoroscopy time was most important, followed by dose rate setting, patient thickness, and skin to source distance. Data obtained from direct observation of procedures as part of a quality improvement project were used to identify opportunities for radiation reduction without prohibiting the safe and effective completion of the procedure.…”