Achievable dose reductions with gonadal shielding for children and adults during abdominal/pelvic radiographic examinations: A Monte Carlo simulation

Abstract

Purpose Recently, medical professionals have reconsidered the practice of routine gonadal shielding for radiographic examinations. The objective of this study was to evaluate the gonadal dose reduction achievable with gonadal shields in the primary beam during abdominal/pelvic radiographic examinations under ideal and non‐ideal shielding placement. Methods CT scans of CIRS anthropomorphic phantoms were used to perform voxelized Monte Carlo simulations of the photon transport during abdominal/pelvic radiographic examinations with standard filtration and 0.1 mm Cu + 1 mm Al added filtration to estimate gonadal doses for an adult, 5 yr old, and newborn phantom with and without gonadal shields. The reduction in dose when the shields were not placed at the ideal locations was also evaluated. The ratio of the number of scattered‐to‐primary photons (SPR) across the anteroposterior (AP) dimension of the phantoms was also reported. Results The simulated dose reduction with ideal shielding placement for the testes and ovaries ranged from 80% to 90% and 55% to 70% respectively. For children, a misalignment of the shield to the gonad of 4 cm reduced the measured dose reduction to the gonads to <10%. For adults, this effect did not occur until the misalignment increased to ~6 cm. Effects of dose reduction with and without the gonadal shields properly placed were similar for standard filtration and added filtration. SPR at the level of the testes was consistently <1 for all phantoms. SPR for ovaries was ~1.5 for the adult and 5‐yr old, and ~1 for the newborn phantom. Conclusion Dose reduction with ideal alignment of the simulated gonadal shield to the gonads in this study was greater for the testes than the ovaries; both reductions were substantial. However, the dose reductions were greatly reduced (to <10%) for both sexes with misalignment of the gonads to the shields by 4 cm for children and 6 cm for adults.

Bismuth Pelvic X-Ray Shielding Reduces Radiation Dose Exposure in Pediatric Radiography

“…In the present study, when the bismuth shielding tablets were tested for protecting the front of the body and the front and sides of the body, the dose measured at the two ovaries did not differ considerably, because the dose was mainly incident from the direction of the main X-rays; hence, shielding the front of the body blocks most of the dose, and the scattered dose produced on both sides of the body is relatively small. In pelvic radiology, positioning of the automatic exposure-control (AEC) chambers, pelvic orientation, and gonadal shielding can potentially optimize the radiation dose and the image quality [ 5 , 18 ]. However, those authors concluded that using gonadal shielding can increase the dose area product, leading to repeated radiography exams, especially in female examinations, which raises the question of the actual utility of gonadal shielding in female pelvic radiography.…”

Evaluation of Radiographers’ Knowledge, Attitudes, and Performance Regarding Gonadal Shielding in Diagnostic Radiology Examinations: Southern Khorasan Province Hospitals of Iran

“…GS reduces received doses to the testes by about 95% and to the ovaries by about 50%. Therefore, GS may be highly effective and play an essential role in decreasing genetic effects (13,14). There are rules and protocols for using GS: GS should be considered when the patient is at or below reproductive age; GS should be inserted when gonads are placed within the radiation field or near the field; and GS should not be an excuse to lead inappropriate patient positioning and poor beam collimation.…”

“…GS was first used in 1900 to protect men against sterility (15). In 1950, anxieties about the risk of radiation on sterilityincreased, and GS was again recommended as a protective tool (13). One crucial point is that GS should be applied so that clinical information remains intact (15)(16)(17).…”