Gonad shielding in paediatric pelvic radiography: disadvantages prevail over benefit

Radiographers' attitudes toward the use of lead contact shielding

INTRODUCTION

Lead contact shielding has been a crucial component of patient radiation protection since it was first introduced in the early 1900s. Concerns surrounding the hereditary effects of ionising radiation were a driver for using lead shielding. Recently the American Association of Physics in Medicine (AAPM) and the British Institute of Radiology (BIR) have published position papers that suggest that lead contact shielding is no longer needed due to reduced radiation doses for x-ray examinations. This work examines radiographers' opinions on these position papers.

METHODS

An online survey with quantitative and qualitative elements was designed to explore knowledge and attitudes toward the BIR and AAPM position papers. The population for this survey was all qualified radiographers.

RESULTS

The majority (59%) of participants are aware of the AAPM guidance, and 76% are aware of the BIR guidance. Given the changes in the gonad tissue weighting factor, 66% believed additional emphasis should be placed on protecting organs and tissues with higher tissue weighting factors. The vast majority (87%) believed lead shielding is not the primary dose reduction strategy, with 82% agreeing that lead shielding may interfere with the AEC.

CONCLUSION

This study identifies a perception that lead protection may still play a role in patient protection, particularly for children and pregnant patients. However, it is not considered the primary mechanism of protection. More specific guidance and information are needed to incorporate the guidance for radiographers into working practice, improving patient care.

IMPLICATIONS FOR PRACTICE

Lead shielding remains a tool for radiation protection in particular examinations, however, its role has diminished in clinical practice.

RECOMMENDATIONS

Additional research is required into the number of repeat x-rays associated with the use of lead shielding and the actual dose saving for shielding outside the field of view. Additional education and specific clarification on when to use and not use lead contact shielding is required.

Exploring radiographers' perceptions and knowledge about patient lead shielding: a cross-sectional study in Greece and Cyprus

The present study aimed to explore radiographers' knowledge, clinical practice and perceptions regarding the use of patient lead shielding in Greece and Cyprus. Qualitative data were analyzed using conceptual content analysis and through the classification of findings into themes and categories. A total of 216 valid responses were received. Most respondents reported not being aware of the patient shielding recommendations issued by the American Association of Physicists in Medicine (67%) or the guidance issued by the British Institute of Radiology (69%). Shielding-related training was generally not provided by radiography departments (74%). Most of them (85%) reported that they need specific guidance on lead shielding practices. Also, 82% of the respondents said that lead shielding should continue to be used outside the pelvic area when imaging pregnant patients. Pediatric patients are the most common patient category to which lead shielding was applied. Significant gaps in relevant training have been identified among radiographers in Greece and Cyprus, highlighting the need for new protocols and provision of adequate training on lead shielding practices. Radiography departments should invest in appropriate shielding equipment and adequately train their staff.

The effect of breast shielding outside the field of view on breast entrance surface dose in axial X-ray examinations: a phantom study

PURPOSE

The purpose of this study was to evaluate the effect of outside-field-of-view (FOV) lead shielding on the entrance surface dose (ESD) of the breast on an anthropomorphic X-ray phantom for a variety of axial skeleton X-ray examinations.

METHODS

Using an anthropomorphic phantom and radiation dosimeter, the ESD of the breast was measured with and without outside-FOV shielding in anterior-posterior (AP) abdomen, AP cervical spine, occipitomental 30° (OM30) facial bones, AP lumbar spine, and lateral lumbar spine radiography. The effect of several exposure parameters, including a low milliampere-seconds technique, grid use, automatic exposure control use, wraparound lead (WAL) use, trolley use, and X-ray table use, on the ESD of the breast with and without outside-FOV shielding was investigated. The mean ESD (μSv) and standard deviation for each radiographic protocol were calculated. A one-tailed Student's t-test was carried out to evaluate whether ESD to the breast was reduced with the use of outside-FOV shielding.

RESULTS

A total of 920 breast ESD measurements were recorded across the different protocol parameters. The largest decrease in mean ESD of the breast with outside-FOV shielding was 0.002 μSv (P = 0.084), recorded in the AP abdomen on the table with a grid, OM30 on the table with a grid, OM30 standard protocol on the trolley, and OM30 on the trolley with WAL protocols. This decrease was found to be statistically non-significant.

CONCLUSION

This study found no significant decrease in the ESD of the breast with the use of outside-FOV shielding for the AP abdomen, AP cervical spine, OM30 facial bones, AP lumbar spine, or lateral lumbar spine radiography across a range of protocols.

[Use of patient radiation shielding in diagnostic and interventional radiology]

The use of patient contact shielding provides an opportunity to reduce patient radiation exposure. Recently, the use has been the subject of controversy. The Radiation Protection Committee has published a recommendation on the use of patient radiation shields by considering the recent findings on dose savings but also the risks of incorrect use. In this article, a specification for the more frequently used types of X‑ray examination is given, which describes whether and which radiation contact shielding should be used. This is accompanied by a rationale for the use or non-use of patient radiation protection agents. Problems and possible errors are explained, as well as how to deal with special situations such as pregnant women and children.

Risks and Safety in Paediatric Radiology

In a highly engaging session at the European Congress of Radiology (ECR)in Vienna, Austria, which took place 1st–5th March 2023 and was chaired by Hans-Joachim Mentzel, experts came together to discuss risks and safety measures, including different radiology practices in children.

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.

[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.

A Study of Radiation Protection Standards Compliance in Hospital Radiographic Departments in Iran

Background

The X-ray is a critical diagnostic and therapeutic tool with harmful effects. The International Commission on Radiological Protection (ICRP) has some recommendations regarding applying radiation protection principles.

Objective

This study aimed to determine the standards of the typical radiation protection in radiographic departments of hospitals in Iran.

Material and Methods

In this cross-sectional descriptive study, the usual radiation protection standards in places, such as the physical environment of the control and waiting rooms, radiographic devices, the physical space of the darkroom, and shielding facilities, were investigated using a checklist in Iran. A total of 84 hospitals in 51 cities throughout Iran were randomly selected, and the checklists were distributed to the radiation protection officers. In hospitals with multiple radiography rooms, the radiation protection officers were asked to complete the checklist about the room with the highest workload as a baseline to evaluate their facilities. Finally, the authors reviewed all checklists.

Results

In radiology departments in control and waiting rooms, the mean of radiation protection was 71.9%. Pregnancy and radiation warning signs and labels were present in 96.1% of the parameters, while gonad shielding protocols were not presented.

Conclusion

The principles of observed radiation protection were unsatisfactory, and it is recommended that surveillance be conducted at frequent intervals.

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.

[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.

European consensus on patient contact shielding

Patient contact shielding has been in use for many years in radiology departments in order to reduce the effects and risks of ionising radiation on certain organs. New technologies in projection imaging and CT scanning such as digital receptors and automatic exposure control systems have reduced doses and improved image consistency. These changes and a greater understanding of both the benefits and the risks from the use of shielding have led to a review of shielding use in radiology. A number of professional bodies have already issued guidance in this regard. This paper represents the current consensus view of the main bodies involved in radiation safety and imaging in Europe: European Federation of Organisations for Medical Physics, European Federation of Radiographer Societies, European Society of Radiology, European Society of Paediatric Radiology, EuroSafe Imaging, European Radiation Dosimetry Group (EURADOS), and European Academy of DentoMaxilloFacial Radiology (EADMFR). It is based on the expert recommendations of the Gonad and Patient Shielding (GAPS) Group formed with the purpose of developing consensus in this area. The recommendations are intended to be clear and easy to use. They are intended as guidance, and they are developed using a multidisciplinary team approach. It is recognised that regulations, custom and practice vary widely on the use of patient shielding in Europe and it is hoped that these recommendations will inform a change management program that will benefit patients and staff.

European consensus on patient contact shielding

Patient contact shielding has been in use for many years in radiology departments in order to reduce the effects and risks of ionising radiation on certain organs. New technologies in projection imaging and CT scanning such as digital receptors and automatic exposure control (AEC) systems have reduced doses and improved image consistency. These changes and a greater understanding of both the benefits and the risks from the use of shielding have led to a review of shielding use in radiology. A number of professional bodies have already issued guidance in this regard. This paper represents the current consensus view of the main bodies involved in radiation safety and imaging in Europe: European Federation of Organisations for Medical Physics, European Federation of Radiographer Societies, European Society of Radiology, European Society of Paediatric Radiology, EuroSafe Imaging, European Radiation Dosimetry Group (EURADOS), and European Academy of DentoMaxilloFacial Radiology (EADMFR). It is based on the expert recommendations of the Gonad and Patient Shielding (GAPS) Group formed with the purpose of developing consensus in this area. The recommendations are intended to be clear and easy to use. They are intended as guidance, and they are developed using a multidisciplinary team approach. It is recognised that regulations, custom and practice vary widely on the use of patient shielding in Europe and it is hoped that these recommendations will inform a change management program that will benefit patients and staff.

European consensus on patient contact shielding

Patient contact shielding has been in use for many years in radiology departments in order to reduce the effects and risks of ionising radiation on certain organs. New technologies in projection imaging and CT scanning such as digital receptors and automatic exposure control (AEC) systems have reduced doses and improved image consistency. These changes and a greater understanding of both the benefits and the risks from the use of shielding have led to a review of shielding use in radiology. A number of professional bodies have already issued guidance in this regard. This paper represents the current consensus view of the main bodies involved in radiation safety and imaging in Europe: European Federation of Organisations for Medical Physics, European Federation of Radiographer Societies, European Society of Radiology, European Society of Paediatric Radiology, EuroSafe Imaging, European Radiation Dosimetry Group (EURADOS), and European Academy of DentoMaxilloFacial Radiology (EADMFR). It is based on the expert recommendations of the Gonad and Patient Shielding (GAPS) Group formed with the purpose of developing consensus in this area. The recommendations are intended to be clear and easy to use. They are intended as guidance, and they are developed using a multidisciplinary team approach. It is recognised that regulations, custom and practice vary widely on the use of patient shielding in Europe and it is hoped that these recommendations will inform a change management program that will benefit patients and staff.

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

BACKGROUND

Radiation using conventional X-ray is associated with exposure of radiosensitive organs and typically requires the use of protection. This study is aimed at evaluating the use of bismuth shielding for radiation protection in pediatric pelvic radiography. The effects of the anteroposterior and lateral bismuth shielding were verified by direct measurements at the anatomical position of the gonads.

METHODS

Radiation doses were measured using optically stimulated luminescence dosimeters (OSLD) and CIRS ATOM Dosimetry Verification Phantoms. Gonad radiographs were acquired using different shields of varying material (lead, bismuth) and thickness and were compared with radiographs obtained without shielding to examine the effects on image quality and optimal reduction of radiation dose. All images were evaluated separately by three pediatric orthopedic practitioners.

RESULTS

Results showed that conventional lead gonadal shielding reduces radiation doses by 67.45%, whereas dose reduction using one layer of bismuth shielding is 76.38%. The use of two layers of bismuth shielding reduces the dose by 84.01%. Using three and four layers of bismuth shielding reduces dose by 97.33% and 99.34%, respectively. Progressively lower radiation doses can be achieved by increasing the number of bismuth layers. Images obtained using both one and two layers of bismuth shielding provided adequate diagnostic information, but those obtained using three or four layers of bismuth shielding were inadequate for diagnosis.

CONCLUSIONS

Bismuth shielding reduces radiation dose exposure providing appropriate protection for children undergoing pelvic radiography. The bismuth shielding material is lighter than lead, making pediatric patients more comfortable and less apt to move, thereby avoiding repeat radiography.

Use of out-of-field contact shielding on patients in medical imaging: A review of current guidelines, recommendations and legislative documents

The use of patient contact-shielding has become a topic of intensive scientific debate. While it has been common practice during the last decades, some studies have questioned the efficiency of using such shielding while others have highlighted the inconsistencies in its application. The objective of this work is to review current recommendations and legislative documents on the use of out-of-field shielding in X-ray imaging, including those from national authorities and from international and national organisations and professional bodies. The review, performed within the framework of the activities of EURADOS Working Group 12, covers available recommendations on use of contact shielding in adult, pregnant and paediatric patients in general radiography, fluoroscopy, computed tomography, mammography and dental radiology. It includes a comprehensive search of 83 documents from 32 countries and 6 international organisations over the last 39 years. In general, using shielding is recommended only under two conditions: if it does not compromise the diagnostic task and the performance of the procedure and/or if it reassures the patient and comforters that they are appropriately protected against potentially harmful effects of radiation. There are very few specific regulatory requirements to use shielding in a particular imaging modality, although they may consider use of shielding either as part of good radiological practice or as requirements for availability of protective or ancillary tools, without further specification of their use. There is a wide variety of positions among documents that recommend out-of-field shielding, those that do not recommend it and those that are not specific. Therefore, evidence-based consensus is still needed to ensure best and consistent practice.

Effect of Silicone Rubber-Lead (SR-Pb) Thickness on Dose Reduction and Image Quality as Gonad Shield

BACKGROUND

Some organs in the body are sensitive to radiation such as eyes, breast, and gonads. Protection of sensitive organs against radiation is necessary. Recently, many sensitive organ shields have been developed from different materials.

OBJECTIVE

The aim of this study is to evaluate the dose reduction and image quality from implementation of Silicone Rubber-Lead (SR-Pb) as an alternative gonad shield in digital radiography (DR).

MATERIAL AND METHODS

In this experimental study, the SR-Pb gonad shields with various thicknesses of 2, 4, 6, 8, and 10 mm were synthesized. This study used the Pb percentage of 5 wt%. An anthropomorphic phantom was used in abdomen plain examinations. The results obtained from the use of the SR-Pb was compared with standard gonad shield, i.e. lead apron. To measure the dose reduction, the Piranha detector was used. The image quality assessment was evaluated with the signal-to-noise ratio (SNR) and the contrast-to-noise ratio (CNR).

RESULTS

This study showed the dose reduction was significant for all SR-Pb thicknesses, and incrementally increased with the increase of the SR-Pb thickness. The minimum and maximum of dose reduction were 22.8% for 2 mm and 66.9% for 10 mm SR-Pb, respectively.

CONCLUSION

Compared to the reference image without gonad shield, the SNR and CNR do not significantly change. Hence, the SR-Pb is probably to be used as an alternative gonad shield.

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

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.

Knowledge translation: Radiographers compared to other healthcare professionals

OBJECTIVES

This narrative review examines the current status of evidence-based practice and knowledge translation in diagnostic radiography. It explores knowledge translation efforts in the allied health professions aimed at systematically implementing evidence-based practice and suggests ways that these may be applied within diagnostic radiography.

KEY FINDINGS

Knowledge translation in diagnostic radiography is in its infancy with numerous examples of key findings of rigorous studies not implemented in practice. Utilising frameworks, models and theories to systematically translate knowledge into evidence-based practice has been shown to be effective in other allied health professions. Whilst few studies in diagnostic radiography report utilising these systematic approaches to implementing evidence-based practice, those that do, show promising results. Attitudes towards evidence-based practice within diagnostic radiography are becoming more positive and it is important to use this positive shift in attitudes to create real evidence-based change in the profession.

CONCLUSION

The potential benefits of systematically translating knowledge into evidence-based practice in diagnostic radiography are wide reaching with positive implications for our patients, the profession and wider community. Leaders at all levels of radiography must work towards implementing evidence-based practice in their daily work.

IMPLICATIONS FOR PRACTICE

Systematic approaches to knowledge translation should be adopted and reported in diagnostic radiography in order to more effectively translate knowledge into evidence-based practice.

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.

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.

Protecting sensitive patient groups from imaging using ionizing radiation: effects during pregnancy, in fetal life and childhood

The frequency of imaging examinations requiring radiation exposure in children (especially CT) is rapidly increasing. This paper reviews the current evidence in radiation protection in pediatric imaging, focusing on the recent knowledge of the biological risk related to low doses exposure. Even if there are no strictly defined limits for patient radiation exposure, it is recommended to try to keep doses as low as reasonably achievable (the ALARA principle). To achieve ALARA, several techniques to reduce the radiation dose in radiation-sensitive patients groups are reviewed. The most recent recommendations that provide guidance regarding imaging of pregnant women are also summarized, and the risk depending on dose and phase of pregnancy is reported. Finally, the risk-benefit analysis of each examination, and careful communication of this risk to the patient, is emphasized.

Patient Shielding in Diagnostic Imaging: Discontinuing a Legacy Practice

OBJECTIVE

Patient shielding is standard practice in diagnostic imaging, despite growing evidence that it provides negligible or no benefit and carries a substantial risk of increasing patient dose and compromising the diagnostic efficacy of an image. The historical rationale for patient shielding is described, and the folly of its continued use is discussed.

CONCLUSION

Although change is difficult, it is incumbent on radiologic technologists, medical physicists, and radiologists to abandon the practice of patient shielding in radiology.

Gonadal shield: is it the Albatross hanging around the neck of developmental dysplasia of the hip research?

PURPOSE

Prospective randomized controlled trials and long-term studies are essential future directions for building -evidence-based practices in developmental dysplasia of the hip (DDH), however, sufficient attrition in data (> 20%) can introduce bias deteriorating research quality. Pelvic radiography is synonymous with DDH assessment and so are -Gonadal Shield (GS) recommendations with pelvic radiography. -Nonetheless, losses to diagnostic information and inadequate protection have been increasingly implicated to GS usage, with significantly worse implications in female patients. Understandably for DDH, a disease with 80% female prevalence, the impact of GS usage on quality of radiographs and readability of radiological data may be drastic. This study aims to objectively define the implications of GS recommendations in DDH patients.

METHODS

Pelvis radiographs of all DDH patients under the hip surveillance programme at a tertiary care hospital with a written protocol for GS usage were evaluated. Images were reviewed for gender, GS presence, adequate gonadal protection and obstruction of essential anatomical landmarks for pelvic indices.

RESULTS

In all, 131 pelvis radiographs with DDH diagnoses (age: 1.25 to 6 years; 107 female, 24 male pelvises) were reviewed. Only 42.67% (56) of pelvis radiographs used GS despite the presence of a clear protocol. Useful anatomical landmarks were obstructed in 58.9% of radiographs with GS present. Lost diagnostic information was more common in female patients than male patients (68.1% versus 11.1%, p < 0.01). GS was ineffective at gonadal protection in 73.2% (41) of the pelvises with worse protection in female patients (78.7% vs 44.4%; p = 0.03).

CONCLUSIONS

Ironically, essential anatomy was obstructed in all the adequately protected female pelvises. Routine GS usage results in substantial attrition of radiographic data in DDH patients.

LEVEL OF EVIDENCE

III.

Female gonadal shielding with automatic exposure control increases radiation risks

BACKGROUND

Gonadal shielding remains common, but current estimates of gonadal radiation risk are lower than estimated risks to colon and stomach. A female gonadal shield may attenuate active automatic exposure control (AEC) sensors, resulting in increased dose to colon and stomach as well as to ovaries outside the shielded area.

OBJECTIVE

We assess changes in dose-area product (DAP) and absorbed organ dose when female gonadal shielding is used with AEC for pelvis radiography.

MATERIALS AND METHODS

We imaged adult and 5-year-old equivalent dosimetry phantoms using pelvis radiograph technique with AEC in the presence and absence of a female gonadal shield. We recorded DAP and mAs and measured organ absorbed dose at six internal sites using film dosimetry.

RESULTS

Female gonadal shielding with AEC increased DAP 63% for the 5-year-old phantom and 147% for the adult phantom. Absorbed organ dose at unshielded locations of colon, stomach and ovaries increased 21-51% in the 5-year-old phantom and 17-100% in the adult phantom. Absorbed organ dose sampled under the shield decreased 67% in the 5-year-old phantom and 16% in the adult phantom.

CONCLUSION

Female gonadal shielding combined with AEC during pelvic radiography increases absorbed dose to organs with greater radiation sensitivity and to unshielded ovaries. Difficulty in proper use of gonadal shields has been well described, and use of female gonadal shielding may be inadvisable given the risks of increasing radiation.

Poor Utility of Gonadal Shielding for Pediatric Pelvic Radiographs

Plain pelvic radiographs are commonly used for a variety of pediatric orthopedic disorders. Lead shielding is typically placed over the gonads to minimize radiation exposure to these sensitive tissues. However, misplaced shielding can sabotage efforts to protect patients from excessive radiation exposure either by not covering radiosensitive tissues or by obscuring anatomic areas of interest, prompting repeat radiographic examinations. The goal of this study was to determine the incidence of misplaced shielding for pelvic radiographs obtained for pediatric orthopedic evaluation. Children 8 to 16 years old who had an anteroposterior or frog lateral pelvic radiograph between 2008 and 2014 were included. A total of 3400 patients met the inclusion criteria, and 84 boys and 84 girls were randomly selected for review. For both boys and girls, the percentage of incorrectly positioned or missing shields was calculated. Chi-square testing was used to compare the frequency of missing or incorrectly placed shields between sexes and age groups. Pelvic shields were misplaced in 49% of anteroposterior and 63% of frog lateral radiographs. Shielding was misplaced more frequently for girls than for boys on frog lateral radiographs (76% vs 51%; P<.05). Pelvic bony landmarks were often obscured by pelvic shielding, with a frequency of 7% to 43%, depending on the specific landmark. The femoral head and acetabulum were obscured by shielding in up to 2% of all images. The findings suggest that accepted pelvic shielding protocols are ineffective. Consideration should be given to alternative protocols or abandonment of this practice. [Orthopedics. 2017; 40(4):e623-e627.].

A paediatric X-ray exposure chart

The aim of this review was to develop a radiographic optimisation strategy to make use of digital radiography (DR) and needle phosphor computerised radiography (CR) detectors, in order to lower radiation dose and improve image quality for paediatrics. This review was based on evidence-based practice, of which a component was a review of the relevant literature. The resulting exposure chart was developed with two distinct groups of exposure optimisation strategies – body exposures (for head, trunk, humerus, femur) and distal extremity exposures (elbow to finger, knee to toe). Exposure variables manipulated included kilovoltage peak (kVp), target detector exposure and milli-ampere-seconds (mAs), automatic exposure control (AEC), additional beam filtration, and use of antiscatter grid. Mean dose area product (DAP) reductions of up to 83% for anterior–posterior (AP)/posterior–anterior (PA) abdomen projections were recorded postoptimisation due to manipulation of multiple-exposure variables. For body exposures, the target EI and detector exposure, and thus the required mAs were typically 20% less postoptimisation. Image quality for some distal extremity exposures was improved by lowering kVp and increasing mAs around constant entrance skin dose. It is recommended that purchasing digital X-ray equipment with high detective quantum efficiency detectors, and then optimising the exposure chart for use with these detectors is of high importance for sites performing paediatric imaging. Multiple-exposure variables may need to be manipulated to achieve optimal outcomes.

Nuking the radiation: minimizing radiation exposure in the evaluation of pediatric blunt trauma

PURPOSE OF REVIEW

Our objective is to highlight recent literature investigating low-radiation diagnostic strategies in the evaluation of pediatric trauma.

RECENT FINDINGS

In the area of minor head injury, research has focused on implementation of validated clinical decision rules into practice to reduce unnecessary computed tomography scans. Clinical observation may also serve as an adjunct to initial assessment and a potential substitute for computed tomography imaging. Subgroups of children with special needs or severe injury mechanisms may also be safely characterized by the clinical decision rule and spared radiation exposure. Physical examination techniques may be useful in diagnosing mandibular fractures. In addition, evidence suggests that plain radiography for evaluation of blunt thoracic trauma may be sufficient in many cases, and computed tomography could be reserved for those with abnormal radiographs, high-risk mechanisms, or abnormal physical findings. Clinical decision rules are able to predict intra-abdominal injury with high sensitivity. Data suggest that skeletal surveys may be modified to limit radiation exposure in the case of suspected nonaccidental trauma.

SUMMARY

More research is needed in development of pediatric-specific clinical decision rules and risk stratification and in testing low-radiation diagnostic modalities in the pediatric trauma population.

Diagnostic radiation exposure in children with spinal dysraphism: an estimation of the cumulative effective dose in a cohort of 135 children from The Netherlands

OBJECTIVE

Based on the assumption that children with spinal dysraphism are exposed to a large amount of ionising radiation for diagnostic purposes, our objective was to estimate this exposure, expressed in cumulative effective dose.

DESIGN

Retrospective cohort study.

SETTINGS

The Netherlands.

PATIENTS

135 patients with spinal dysraphism and under 18 years of age treated at our institution between 1991 and 2010.

RESULTS

A total of 5874 radiological procedures were assessed of which 2916 (49.6%) involved ionising radiation. Mean cumulative effective dose of a child with spinal dysraphism during childhood was 23 mSv, while the individual cumulative effective dose ranged from 0.1 to 103 mSv. Although direct radiography accounted for 81.7% of examinations, the largest contributors to the cumulative effective dose were fluoroscopic examinations (40.4% of total cumulative effective dose).

CONCLUSIONS

Exposure to ionising radiation and associated cancer risk were lower than expected. Nevertheless, the use of ionising radiation should always be justified and the medical benefits should outweigh the risk of health detriment, especially in children.

Optimizing bone surveys performed for suspected non-accidental trauma with attention to maximizing diagnostic yield while minimizing radiation exposure: utility of pelvic and lateral radiographs

BACKGROUND

Skeletal surveys for non-accidental trauma (NAT) include lateral spinal and pelvic views, which have a significant radiation dose.

OBJECTIVE

To determine whether pelvic and lateral spinal radiographs should routinely be performed during initial bone surveys for suspected NAT.

MATERIALS AND METHODS

The radiology database was queried for the period May 2005 to May 2011 using CPT codes for skeletal surveys for suspected NAT. Studies performed for skeletal dysplasia and follow-up surveys were excluded. Initial skeletal surveys were reviewed to identify fractures present, including those identified only on lateral spinal and/or pelvic radiographs. Clinical information and MR imaging was reviewed for the single patient with vertebral compression deformities.

RESULTS

Of the 530 children, 223 (42.1%) had rib and extremity fractures suspicious for NAT. No fractures were identified solely on pelvic radiographs. Only one child (<0.2%) had vertebral compression deformities identified on a lateral spinal radiograph. This infant had rib and extremity fractures and was clinically paraplegic. MR imaging confirmed the vertebral body fractures.

CONCLUSION

Since no fractures were identified solely on pelvic radiographs and on lateral spinal radiographs in children without evidence of NAT, nor in nearly all with evidence of NAT, inclusion of these views in the initial evaluation of children for suspected NAT may not be warranted.

Fluoroscopic radiation exposure during hip arthroscopy

PURPOSE

The purpose of this study was to assess the maximal dose area product (DAP) of radiation received by women during hip arthroscopy; we used computer modeling to determine the theoretical risk to a fetus.

METHODS

We studied 116 female patients of childbearing age who underwent hip arthroscopy. We retrospectively collected data from the procedure, hip pathologic process, and dose of irradiation in milligray. We calculated the theoretical dose of radiation to the fetus and the risk of childhood hereditary disease and cancer.

RESULTS

Labral tear (52%) was the most common indication for hip arthroscopy, with labral resection the most common procedure undertaken. The maximal DAP to the patient was 9.52 mGy, and the maximal DAP was estimated to be 2.99 mGy to the fetus. The risk of hereditary disease and childhood cancer for the fetus was calculated to be 1 in 14,000 and 1 in 11,000, respectively.

CONCLUSIONS

Fluoroscopy used in hip arthroscopy generates a maximal theoretical dose of 2.99 mGy to the fetus, which places the procedure in the low-risk category.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.