Gonad shielding in paediatric pelvic radiography: disadvantages prevail over benefit

Abstract

ObjectiveTo re-evaluate gonad shielding in paediatric pelvic radiography in terms of attainable radiation risk reduction and associated loss of diagnostic information.MethodsA study on patient dose and the quality of gonad shielding was performed retrospectively using 500 pelvic radiographs of children from 0 to 15 years old. In a subsequent study, 195 radiographs without gonad shielding were included. Patient doses and detriment adjusted risks for heritable disease and cancer were calculated with and without gonad shielding.ResultsFor girls, gonad shields were placed incorrectly in 91% of the radiographs; for boys, in 66%. Without gonad shielding, the hereditary detriment adjusted risk for girls ranged between 0.1 × 10−6 and 1.3 × 10−6 and for boys between 0.3 × 10−6 and 3.9 × 10−6, dependent on age. With shielding, the reduction in hereditary risk for girls was on average 6 ± 3% of the total risk of the radiograph, for boys 24 ± 6%. Without gonad shielding, the effective dose ranged from 0.008 to 0.098 mSv.ConclusionsWith modern optimised X-ray systems, the reduction of the detriment adjusted risk by gonad shielding is negligibly small. Given the potential consequences of loss of diagnostic information, of retakes, and of shielding of automatic exposure-control chambers, gonad shielding might better be discontinued.

Gonad Shielding for Patients Undergoing Conventional Radiological Examinations: Is There Cause for Concern?

“…Liakos et al (2001) reported that only 1.6% of pelvic radiographs had the correct placement of gonad shields (14). The results of this study are worrying as the importance of gonad shielding has been well established in the literature (4,6,11). It seems that, in procedures in which gonads are exposed in the primary beam, it is difficult to correctly position the gonad shields so that gonads are completely obscured whilst not concealing important anatomical data (4,6,7,11).…”

“…The results of this study are worrying as the importance of gonad shielding has been well established in the literature (4,6,11). It seems that, in procedures in which gonads are exposed in the primary beam, it is difficult to correctly position the gonad shields so that gonads are completely obscured whilst not concealing important anatomical data (4,6,7,11). MacKay et al (2012) believed that "one of the main reasons for omission of the gonad shield is a lack confidence or skill in the gonad shield placement of radiographers and the attitude that gonad shielding is not applied to patients whilst not compromising the diagnostic quality of the image" (7).…”

“…Shielding is one of the fundamental methods by which to protect radiosensitive organs such as the gonads (5). Various studies have been carried out to evaluate gonad shielding during radiological examinations using pelvic radiographs (3,4,6), questionnaires (7) and direct observation (8). Gonadal shields are divided into contact and shadow shields.…”

“…Various designs of gonad shields are available, depending on the patient's age and gender. Gonad shielding should always be performed if the gonads are within or near the primary beam (5 cm), unless the presence of the shield disturbs important anatomical data (6,10,11). Proper gonad shielding can reduce the dose to the testes and the ovaries by about 95% and 50%, respectively (6,11).…”

“…Gonad shielding should always be performed if the gonads are within or near the primary beam (5 cm), unless the presence of the shield disturbs important anatomical data (6,10,11). Proper gonad shielding can reduce the dose to the testes and the ovaries by about 95% and 50%, respectively (6,11). A lack of or inadequate shielding of the gonads may increase the exposure of these organs and result in both genetic and hereditary effects in future generations (12,13).…”