Gonad contact shielding in digital radiography: A questionnaire survey.

PURPOSE: The use of gonad contact shielding (GCS) in radiology departments has varied across countries, possibly because, until recently, there was no agreed consensus with mixed evidence supporting its use. This study aims to explore radiographers' use and opinion on GCS in digital radiography (DR) and to evaluate whether radiographers' use of GCS is associated with their gender, highest educational qualification, and/or years of experience. METHOD: An online survey was sent via email to potential participants through the Society of Medical Radiographers Malta (SRM) as well as social media posts on local radiography pages. Descriptive and inferential statistics were used to analyse the collected data. RESULTS: Almost half of the registered radiographers working in radiology departments in Malta (n = 101/203) completed the survey (49.7 % response rate). 61.4 % of participating radiographers indicated they 'often' use GCS in some patients, with 56.4 % stating they perceive GCS as an effective tool to protect the gonads from radiation exposure in DR. Equally, 56.4 % claimed that GCS use is guided by local rules and/or departmental protocols. While 58.4 % indicated that patients' gender does not impact their use of GCS, patients' age does influence their use. No statistically significant association was noted between radiographers' likeliness of using GCS and their gender, highest educational qualification, and/or years of experience. CONCLUSIONS: Some misconceptions and uncertainties among radiographers concerning the benefits and risks of using GCS were noted. Local radiology departments should look into their protocols and assess the need for an update aligned with the latest recommendations.

[Verification of Effectiveness of Gonad Shielding in Female Hip Joint Radiography].

PURPOSE: It has been reported that the placement of protective equipment in female pelvic radiography is predominantly inadequate compared with that of male. We analyzed the actual situation of ovarian shielding by protective devices using X-ray, CT, and MR images obtained in the past, and evaluated the effectiveness of gonadal protection in female hip radiography. METHODS: The ovaries were contoured in MR images and the pelvic bone was extracted by CT images. The MR/CT fusion images were created using a 3D workstation. The amount of physiological fluctuation in the ovarian location was measured. The fusion images in the ray-summation display were manually superimposed with the X-ray image, and the percentage of ovaries that could be shielded by the protective device was classified into four categories: (a) complete protection, (b) partial protection, (c) failure of protection, and (d) image retaking. RESULTS: The mean and maximum ovarian fluctuations were 1.1 cm and 3.9 cm in the superior and inferior directions, respectively, and 0.7 cm and 2.0 cm in the left and right directions, respectively. The percentage of ovaries shielded was 18.9% for complete protection, 58.5% for partial protection, 15.1% for inadequate protection, and 7.5% for image retaking. CONCLUSION: The effectiveness of gonadal protection is low because the protective device could not cover the entire ovary in about 80% of the female hip radiographs.

[Recent Trends in Medical Radiation Protection].

In recent years, the field of medical radiation protection has entered an era of drastic changes. In addition to international trends, it may also be related to the increased awareness of radiation and radiation effects among the Japanese people due to the Fukushima nuclear accident in March 2011. As a result, with the revision of laws and regulations, strict control is required for medical radiation safety management and management of radiation workers. As a recent movement on radiation protection, this article reviews the changes in the threshold dose and dose limit of the lens of the eye, medical radiation safety management due to revision of medical law enforcement regulations, diagnostic reference levels, domestic and international trends regarding gonad shielding during radiography, trends toward new ICRP recommendation, and risk communication from recent trends in medical radiation protection.

Paediatric gonad shielding in pelvic radiography: A systematic review and meta-analysis.

INTRODUCTION: The British Institute of Radiology (BIR) and American Association of Physicists in Medicine (AAPM) have recommended that gonad shielding is no longer used during pelvic X-ray examinations. The BIR guidance states that shielding may still be considered for use on males, but should not be used on females. This paper aimed to evaluate if this decision was supported by evidence from practice, by comparing the accuracy of gonad shield placement in paediatric males and females. METHODS: A systematic review of databases including EMBASE, MEDLINE and PubMed was performed in February 2021. Studies were considered eligible if they provided data on the use of gonad shielding during pelvic X-ray examinations on male and female patients under the age of 18. Nine studies met the inclusion criteria and data extraction was performed. Quality appraisal was undertaken, and a meta-analysis of shielding accuracy was performed on seven studies. RESULTS: The results from the meta-analysis (2187 total radiographs) demonstrated that female patients were significantly more likely (OR 1.38, 95% CI 0.88-1.87) than males to have gonad shields placed inaccurately (p value < 0.001). CONCLUSION: Gonad shield placement on paediatric female patients is significantly less accurate than on males, and so the results support the AAPM and BIR guidance to stop the practice for females. Shield application may also be frequently inaccurate for males, but the review does not provide clear evidence for or against continuing the practice for males. IMPLICATIONS FOR PRACTICE: Discontinuing the use of gonad shields in paediatric pelvic radiography on female patients is supported. Any continued use on male patients, or for reasons such as psychological reassurance, should be subject to enhanced training and audit to ensure benefits outweigh any risks.

Gonad shield placement accuracy in pelvic radiographs for male patients: A prospective phantom study and survey of third year undergraduate diagnostic radiography students".

INTRODUCTION: Little research has focused on the accuracy of gonad shield placement, especially by students. While studies have investigated the presence of gonad shields they do not aim to measure accuracy but only look at repeatability. This study aimed to establish students' knowledge of gonad shields and their accuracy in placing it. METHODS: Following an invitation email and informed consent, students completed a 7-question questionnaire and placed a gonad shield on a Pixi full body adult phantom (male configuration). The phantom was x-rayed and images were assessed for gonad shield positioning in terms of obscuring bony anatomy, correct orientation and distance from a "gold standard" position. RESULTS: 36% of images displayed shields covering bony anatomy while 16% of shields were incorrectly orientated. All shields incorrectly orientated also covered bony anatomy. Statistical significance was seen between incorrect shield orientation and the obscuring of bony anatomy (p = 0.01). Dispersion of positioning error measurements ranged from -6.80 mm (better placed than the "gold standard") to 62.35 mm inferiorly, with an average 28.22 mm inferiorly. CONCLUSION: The average misplacement of 28.22 mm suggests participants placed the gonad shielding lower than necessary to avoid obscuring bony anatomy. The 36% of misplaced shields, while lower than in previous studies, is still a significant number of radiographs that would require repeats. IMPLICATIONS FOR PRACTICE: Given the associated difficulties surrounding gonad shields and their placement, this study supports previous research suggesting that the benefit of using gonad shielding is questionable.

[About Gonad Protection Based on Ovarian Position in Hip Plain Radiography].

PURPOSE: In gonad protection, it is difficult to identify the position from the body surface during shielding because the position and size of the ovary vary from individual to individual, and it is not possible to evaluate whether the protective equipment is correctly placed at the position of the ovary. Therefore, the position of the ovary with respect to the pelvis was clarified, and the effectiveness of gonad protection in the front and side of the hip joint was evaluated. METHODS: From the image of the pelvis taken with an MRI device, the inner and outer edges of the ovary, the upper and lower edges and the long and short axes of the pelvis, and the depth of the ovary were measured, and the position of the ovary was calculated based on the ratio of the ovary to the pelvis. A pelvic schema was created, and the position of the ovary was synthesized on the schema. In addition, the shielding rate was calculated when lead-containing rubber for the protection of the gonads was used. RESULTS: In front of the pelvis, the ovaries were present throughout the pelvic cavity. On the anterior surface, placing the shield on the caudal side up to the line connecting the centers of the left and right femoral heads had a shielding effect of about 88%. On the lateral side, shielding the pubic upper limbs from the ischial body could reduce the exposure of the unhealthy ovaries by 99%. However, when the gonad protection was placed at the height of the line connecting the anterior superior iliac spines, the shielding rate from the left and right ovarian distribution was about 13%, so the disadvantage of using the protective equipment was greater. CONCLUSION: For gonad protection, the presence or absence of use should be judged by using the shielding rate according to the shape of the protective equipment as an index.

Impact of gonad shielding for AP pelvis on dose and image quality on different female sizes: A phantom study.

INTRODUCTION: In clinical practice AP pelvis standard protocols are suitable for average size patients. However, as the average body size has increased over the past decades, radiographers have had to improve their practice in order to ensure that adequate image quality with minimal radiation dose to the patient is achieved. Gonad shielding has been found to be an effective way to reduce the radiation dose to the ovaries. However, the effect of increased body size, or fat thickness, in combination with gonad shielding is unclear. The goal of the study was to investigate the impact of gonad shielding in a phantom of adult female stature with increasing fat thicknesses on SNR (as a measure for image quality) and dose for AP pelvis examination. METHODS: An adult Alderson female pelvis phantom was imaged with a variety of fat thickness categories as a representation of increasing BMI. 72 images were acquired using both AEC and manual exposure with and without gonad shielding. The radiation dose to the ovaries was measured using a MOSFET system. The relationship between fat thickness, SNR and dose when the AP pelvis was performed with and without shielding was investigated using the Wilcoxon signed rank test. P-values < 0.05 were considered to be statistically significant. RESULTS: Ovary dose and SNR remained constant despite the use of gonad shielding while introducing fat layers. CONCLUSION: The ovary dose did not increase with an increase of fat thickness and the image quality was not altered. IMPLICATIONS FOR PRACTICE: Based on this phantom study it can be suggested that obese patients can expect the same image quality as average patients while respecting ALARA principle when using adequate protocols.

El fin de la protección gonadal en radiografía de pelvis: una revisión / The end of gonadal protection in pelvic radiography: a review

Resumen: La protección gonadal ha sido durante largo tiempo un importante factor para abordar el requisito "tan bajo como sea razonablemente posible" ALARA. El presente artículo realiza una revisión sistemática sobre la utilidad de la protección gonadal en la radiografía de pelvis en la cual se han destacado los factores que tienen que ver con su realización diaria, es decir, la dosis de radiación involucrada, la radiosensibilidad de las gónadas, la posición del protector gonadal y el factor psicológico de la población en relación con su uso. La incorporación de equipamientos modernos, con dosis y protocolo optimizados, transforma el beneficio de la protección en un tema al menos debatible. Mientras algunos siguen respaldando la medida, otros organismos y autores ya no la respaldan. Es necesario reconsiderar prácticas actuales fundadas en consensos científicos que pueden estar obsoletos y considerar el factor de cambio cultural basados en estos nuevos consensos para su implementación, sin generar mayor preocupación en la población.

Abstract: Gonadal protection has long been an important factor in addressing the ALARA "as low as reasonably possible" requirement. This article performs a systematic review on the usefulness of gonadal protection in pelvic radiography, in which the factors that have to do with its daily performance have been highlighted, that is, radiation dose involved, the radiosensitivity of the gonads, the position of the gonadal shielding and the psychological factor of the population in relation to its use. The incorporation of modern equipment, with optimized dose and protocols, transforms the benefit of gonad shielding into an issue that is at least debatable. While some continue to support the measure, other agencies and authors no longer support it. It is necessary to reconsider current practices based on scientific consensus that may be obsolete and consider the factor of cultural change based on these new consensus for its implementation, without generating major concern in the population.

The impact of gonad shielding in anteroposterior (AP) pelvis projections in an adult: A phantom study utilising digital radiography (DR).

INTRODUCTION: Positioning relative to the lateral automatic exposure control (AEC) chambers (cranial/caudal orientation) optimises dose and image quality in pelvic radiography. In the cranial orientation introducing gonad shielding (GS) in females may increase radiation dose. The aim of this study was to fully optimise the combination of pelvis orientation and use of GS in both male and females. METHODS: An anthropomorphic pelvis phantom was exposed, with dose area product (DAP) recorded, in both orientations without GS and four conditions with GS: cranial orientation (female/male), caudal orientation (female/male). A 4 cm × 4 cm grid incorporating thirteen positions for the GS resulted in 52 experimental settings. Blind image quality assessment, utilising a modified scale, was undertaken by two experienced observers. RESULTS: Comparing no GS (caudal orientation) to female GS, no significant change in DAP was seen (3.97 v 4.03 dGy*cm2; Mann-Whitney p = 0.060). Comparing no GS (cranial orientation) to male GS no significant change in DAP was seen (8.66 v 8.77 dGy*cm2; Mann-Whitney; p = 0.210). DAP increased significantly with introduction of female GS in the cranial orientation (23%: 8.66 v 10.65 dGy*cm2, Mann-Whitney; p < 0.001) and male GS in the caudal orientation (22.8%: 3.97 v 4.87 dGy*cm2, Mann-Whitney; p < 0.001). Significantly higher repeat rates (Chi-squared test; p < 0.001) were seen for GS in female (85-100%) compared to male (30.8%). CONCLUSION: The use of gonad shielding can increase DAP and lead to repeats being required, with more required for female GS usage, suggesting the utility of GS for pelvis examinations is questionable. IMPLICATIONS FOR PRACTICE: Optimisation of radiation dose in pelvic radiographic examinations utilising AEC terminated exposures requires consideration of AEC chamber position and GS usage.

Gonad shielding in pelvic radiography: modern optimised X-ray systems might allow its discontinuation.

OBJECTIVE: As gonad shielding is currently under debate, this study evaluates the practice, from its introduction in about 1905 until today. METHODS: The literature was searched for developments in shielding and insights into the effects of ionising radiation on gonads. Based on own pre-1927 dose reconstructions, reported doses after 1927, a 2015-report from the European Union and recent own measurements, the effects of technological evolution and optimisation on radiation dose and hereditary risk were assessed. RESULTS: In the 1900s, gonad shielding was first applied to prevent male sterility, but was discontinued when instrumental developments led to reduced radiation doses. In the 1950s, concerns about hereditary risks intensified and gonad shielding was recommended again, becoming routine worldwide. Imaging-chain improvements over time were considerable: in 2018, the absorbed dose was 0.5% of its 1905 value for the testes and 2% for the ovaries, our optimised effective dose a factor five lower than the value corresponding to the current EU diagnostic reference level, and the reduction in detriment-adjusted risk by shielding less than 1 × 10-6 for women and 5 × 10-6 for men. CONCLUSIONS: Assessment of pelvic doses revealed a large reduction in radiation risks facilitated by technological developments. Optimisation likewise contributed, but unfortunately, its potential was never adequately exploited. Today, using a modern and optimised X-ray system, gonad shielding can be safely discontinued for women. For men, there might be a marginal benefit, but potential negative side-effects may well dominate. Discontinuation of gonad shielding seems therefore justifiable.