Risk for radiation-induced cataract for staff in interventional cardiology: is there reason for concern?

Managing radiation safety and protection in gastroenterology in Japan: insights from the REX-GI study

Fluoroscopy-guided gastrointestinal procedures, including gastrointestinal stenting, balloon-assisted endoscopy (BAE), endoscopic retrograde cholangiopancreatography (ERCP), and endoscopic ultrasound (EUS), are essential for diagnosis and treatment in gastroenterology. Such procedures involve radiation exposure that necessitates strict safety measures to protect patients, doctors, and medical staff. The April 2020 update to Japan's Ionizing Radiation Injury Prevention Regulations for occupational exposure reduced the lens exposure dose limit to approximately one-seventh of its previous level. This change highlights the need for improved safety protocols. Without adaptation, the sustainability of fluoroscopy-based endoscopic techniques could be at risk due to the potential to exceed these new limits. This review examines the current state of medical radiation exposure in the field of gastroenterology in Japan and discusses the findings of the REX-GI study.

Estimating brain and eye lens dose for the cardiologist in interventional cardiology-are the dose levels of concern?

OBJECTIVES

To establish conversion coefficients (CCs), between mean absorbed dose to the brain and eye lens of the cardiologist and the air kerma-area product, PKA, for a set of projections in cardiac interventional procedures. Furthermore, by taking clinical data into account, a method to estimate the doses per procedure, or annual dose, is presented.

METHODS

Thermoluminescence dosimeters were used together with anthropomorphic phantoms, simulating a cardiologist performing an interventional cardiac procedure, to estimate the CCs for the brain and eye lens dose for nine standard projections, and change in patient size and x-ray spectrum. Additionally, a single CC has been estimated, accounting for each projections fraction of use in the clinic and associated PKA using clinical data from the dose monitoring system in our hospital.

RESULTS

The maximum CCs for the eye lens and segment of the brain, is 5.47 μGy/Gycm2 (left eye lens) and 1.71 μGy/Gycm2 (left brain segment). The corresponding weighted CCs: are 3.39 μGy/Gycm2 and 0.89 μGy/Gycm2, respectively.

CONCLUSIONS

Conversion coefficients have been established under actual scatter conditions, showing higher doses on the left side of the operator. Using modern interventional x-ray equipment, interventional cardiac procedures will not cause high radiation dose levels to the operator when a ceiling mounted shield is used, otherwise there is a risk that the threshold dose values for cataract will be reached.

ADVANCE IN KNOWLEDGE

In addition to the CCs for the different projections, methods for deriving a single CC per cardiac interventional procedure and dose per year were introduced.

Medical staff dose estimation during pediatric cardiac interventional procedures

The purpose of this study is to evaluate the occupational doses (eye lens, extremities and whole body) in paediatric cardiac interventional and diagnostic catheterization procedures performed in a paediatric reference hospital located in Recife, Pernambuco. For eye lens dosimetry, the results show that the left eye receives a higher dose than the right eye, and there is a small difference between the doses received during diagnostic (D) and therapeutic (T) procedures. The extrapolated annual values for the most exposed eye are close to the annual limit. For doses to the hands, it was observed that in a significant number of procedures (37 out of 45 therapeutic procedures, or 82%) at least one hand of the physician was exposed to the primary beam. During diagnostic procedures, the physician's hand was in the radiation field in 11 of the 17 catheterization procedures (65%). This resulted in a 10-fold increase in dose to the hands. The results underscore the need for optimization of radiation safety and continued efforts to engage staff in a radiation safety culture.

Occupational Risks of Radiation Exposure to Cardiologists

PURPOSE OF REVIEW

Invasive cardiologists are exposed to large amounts of ionizing radiation. This review aims to summarize the main occupational risks in a radiation-exposed cardiology practice.

RECENT FINDINGS

We carried out a literature review on the subject. The studies reviewed allowed us to list six main health risk categories possibly associated with radiation exposure among cardiologists: deoxyribonucleic acid (DNA) and biochemical damages; cancers; ocular manifestations; olfaction, vascular, and neuropsychological alterations; musculoskeletal problems; and reproductive risks. Our descriptive analysis demonstrates higher risks of DNA damage and lens opacities among radiation-exposed cardiology staff. Surveys and questionnaires have demonstrated a higher risk of musculoskeletal disease in exposed workers. Studies reported no difference in cancer frequency between radiation-exposed workers and controls. Changes in olfactory performance, neuropsychological aspects, and vascular changes have also been reported. Limited literature supports the security of continuing radiation-exposed work during pregnancy. Therefore, there is an urgent need to increase knowledge of the occupational risks of radiation exposure and to adopt technologies to reduce them.

Robotic Assisted Percutaneous Coronary Intervention: Initial Australian Experience

BACKGROUND & AIM

Robotic-assisted percutaneous coronary intervention (R-PCI) has been increasingly performed overseas. Initial observations have demonstrated its clinical efficacy and safety with additional potential benefits of more accurate lesion assessment and stent deployment, with reduced radiation exposure to operators and patients. However, data from randomised controlled trials or clinical experience from Australia are lacking.

METHODS

This was a single-centre experience of all patients undergoing R-PCI as part of the run-in phase for an upcoming randomised clinical trial (ACTRN12623000480684). All R-PCI procedures were performed using the CorPath GRX robot (Corindus Vascular Robotics, Waltham, Massachusetts, USA). Key inclusion criteria included patients with obstructive coronary disease requiring percutaneous coronary intervention. Major exclusion criteria included ST-elevation myocardial infarction, cardiogenic shock or lesions deemed unsuitable for R-PCI by the operator. Clinical success was defined as residual stenosis <30% without in-hospital major adverse cardiovascular events (MACE). Technical success was defined as the completion of the R-PCI procedure without unplanned manual conversion. Procedural characteristics were compared between early (cases 1-3) and later (cases 4-21) cases.

RESULTS

Twenty-one (21) patients with a total of 24 lesions were analysed. The mean age of patients was 66.5 years, and 66% of cases were male. Radial access was used in 18 cases (86%). Most lesions were American Heart Association/American College of Cardiology class B2/C (66%). Clinical success was achieved in 100% with manual conversion required in four cases (19%). No procedural complications or in-hospital MACE occurred. Compared to the early cases, later cases had a statistically significantly shorter fluoroscopy time (44.0mins vs 25.2mins, p<0.007), dose area product (967.3 dGy.cm2 vs 361.0dGy.cm2, p=0.01) and air kerma (2484.3mGy vs 797.4mGy, p=0.009) with no difference in contrast usage (136.7mL vs 131.4mL, p=0.88).

CONCLUSIONS

We present the first clinical experience of R-PCI in Australia using the Corindus CorPath GRX robot. We achieved clinical success in all patients and technical success in the majority of cases with no procedural complications or in-hospital MACE. With increasing operator and staff experience, cases required shorter fluoroscopy time and less radiation exposure but similar contrast usage.

Radiation Exposure to the Interventional Echocardiographers and Sonographers: A Call to Action

Interventional echocardiography is a rapidly growing field within the disciplines of cardiology and anesthesiology, with the rise of advanced transcatheter procedures making skilled imagers more important than ever. However, these procedures also involve frequent manipulation of the transesophageal echocardiography probe, which means interventional echocardiographers (IEs) are at risk of long-term occupational radiation exposure. Studies have shown that radiation exposure is linked to various health issues, including cancer, cataracts, hypertension, hyperlipidemia, endothelial dysfunction, vascular aging, and early atherosclerosis. While there is increasing awareness of the occupational radiation dose limits and the need for better shielding methods, the importance of radiation safety for the IE is still not sufficiently prioritized in most cardiac catheterization laboratories/hybrid operating rooms. This is partly due to a paucity of studies looking at long-term radiation exposure to the IE, as this field is newer than that of interventional cardiologists.

Background Factors Affecting the Radiation Exposure of the Lens of the Eye among Nurses in Interventional Radiology: A Quantitative Observational Study

With the International Commission on Radiological Protection's (ICRP) reduction in the radiation dose threshold for cataracts, evaluating and preventing radiation exposure to the lens of the eye among interventional radiology (IR) staff have become urgent tasks. In this study, we focused on differences in lens-equivalent dose (HT Lens) to which IR nurses in three hospitals were exposed and aimed to identify factors underlying these differences. According to analyses of time-, distance-, and shielding-related factors, the magnitude of the HT Lens dose to which IR nurses were exposed could be explained not by time or shielding but by the distance between the X-ray exposure field and the location of the IR nurse. This distance tended to be shorter in hospitals with fewer staff. The most effective means of reducing the exposure of the lenses of IR nurses' eyes to radiation is to position them at least two meters from the radiation source during angiography procedures. However, some hospitals must provide IR departments with comparatively few staff. In work environments where it is infeasible to reduce exposure by increasing distance, interventions to reduce time by managing working practices and investment in shielding equipment are also important. This study was not registered.

Assessing lead curtains' impact on radiation protection in coronary interventions

The objective of this investigation is to assess the impact of supplementary lead curtains on the reduction of radiation dose exposure to operators during coronary interventional procedures. Seven standard positions during coronary angiography (foot, right foot, head, left foot, left lateral, left head, and right lateral) were simulated on a standard anthropomorphic phantom with radial artery access. Measurements were taken at two different heights, 125 cm and 155 cm, and dosimeters were used to measured surface incident dose rates for the first and second operators, both with and without additional lead curtains at various positions. Each position was measured 20 times, and arithmetic means were computed. At-test was utilised to compare dose rates with and without supplementary lead curtains, as well as dose rates with additional lead curtains at varying heights. The finding indicate that the dose rates of the first operator with supplementary lead curtains were not significantly lower compared to those without, except for the 125 cm head and left foot positions and the 155 cm head position with the additional lead curtain edge 10 cm below the umbilical level (tumbilical= 0.9, 0.4, 0.5,P> 0.05). The dose rates of the second operator with additional lead curtains were significantly lower than those without, with statistically significant differences (P< 0.05). The arithmetic mean dose rates for the first and second operators at each position were lowest when the upper edge of the additional lead curtain was situated 10 cm above the umbilical level. Employing supplementary lead curtains during coronary interventions effectively reduces radiation doses received by operators. The protective effect is enhanced when the additional lead curtain is closer to the irradiation field. Hence, it is recommended that additional curtains be employed judiciously, while ensuring that clinical procedures are not impeded, in order to effectively mitigate the radiation exposure of operators.

Robotic-Assisted Solutions for Invasive Cardiology, Cardiac Surgery and Routine On-Ward Tasks: A Narrative Review

Robots are defined as programmable machines that can perform specified tasks. Medical robots are emerging solutions in the field of cardiology leveraging recent technological innovations of control systems, sensors, actuators, and imaging modalities. Robotic platforms are successfully applied for percutaneous coronary intervention, invasive cardiac electrophysiology procedures as well as surgical operations including minimally invasive aortic and mitral valve repair, coronary artery bypass procedures, and structural heart diseases. Furthermore, machines are used as staff-assisting tools to support nurses with repetitive clinical duties i.e., food delivery. High precision and resolution allow for excellent maneuverability, enabling the performance of medical procedures in challenging anatomies that are difficult or impossible using conventional approaches. Moreover, robot-assisted techniques protect operators from occupational hazards, reducing exposure to ionizing radiation, and limiting risk of orthopedic injuries. Novel automatic systems provide advantages for patients, ensuring device stability with optimized utilization of fluoroscopy. The acceptance of robotic technology among healthcare providers as well as patients paves the way for widespread clinical application in the field of cardiovascular medicine. However, incorporation of robotic systems is associated with some disadvantages including high costs of installation and expensive disposable instrumentations, the need for large operating room space, and the necessity of dedicated training for operators due to the challenging learning curve of robotic-assisted interventional systems.

Challenges and Burdens in the Coronary Artery Disease Care Pathway for Patients Undergoing Percutaneous Coronary Intervention: A Contemporary Narrative Review

Clinical and economic burdens exist within the coronary artery disease (CAD) care pathway despite advances in diagnosis and treatment and the increasing utilization of percutaneous coronary intervention (PCI). However, research presenting a comprehensive assessment of the challenges across this pathway is scarce. This contemporary review identifies relevant studies related to inefficiencies in the diagnosis, treatment, and management of CAD, including clinician, patient, and economic burdens. Studies demonstrating the benefits of integration and automation within the catheterization laboratory and across the CAD care pathway were also included. Most studies were published in the last 5-10 years and focused on North America and Europe. The review demonstrated multiple potentially avoidable inefficiencies, with a focus on access, appropriate use, conduct, and follow-up related to PCI. Inefficiencies included misdiagnosis, delays in emergency care, suboptimal testing, longer procedure times, risk of recurrent cardiac events, incomplete treatment, and challenges accessing and adhering to post-acute care. Across the CAD pathway, this review revealed that high clinician burnout, complex technologies, radiation, and contrast media exposure, amongst others, negatively impact workflow and patient care. Potential solutions include greater integration and interoperability between technologies and systems, improved standardization, and increased automation to reduce burdens in CAD and improve patient outcomes.

Effectiveness of staff radiation protection devices for interventional cardiology procedures

PURPOSE

To evaluate the effectiveness of currently available radioprotective (RP) devices in reducing the dose to interventional cardiology staff, especially to the eye lens and brain.

METHODS

The performances of five RP devices (masks, caps, patient drapes, staff lead and lead-free aprons and Zero-Gravity (ZG) suspended radiation protection system) were assessed by means of Monte Carlo (MC) simulations. A geometry representative of an interventional cardiology setup was modelled and several configurations, including beam projections and staff distance from the source, were investigated. In addition, measurements on phantoms were performed for masks and drapes.

RESULTS

An average dose reduction of 65% and 25% to the eyes and the brain respectively was obtained for the masks by MC simulations but a strong influence of the design was observed. The cap effectiveness for the brain ranges on average between 13% and 37%. Nevertheless, it was shown that only some upper parts of the brain were protected. There was no significant difference between the effectiveness of lead and lead-free aprons. Of all the devices, the ZG system offered the highest protection to the brain and eye lens and a protection level comparable to the apron for the organs normally covered.

CONCLUSION

All investigated devices showed potential for dose reduction to specific organs. However, for masks, caps and drapes, it strongly depends on the design, exposure conditions and staff position. Therefore, for a clinical use, it is recommended to evaluate their effectiveness in the planned conditions of use.

Occupational and patient doses for interventional radiology integrated into a dose management system

OBJECTIVES

The International Commission on Radiological Protection recommends managing patient and occupational doses as an integrated approach, for the optimisation of interventional procedures. The conventional passive personal dosimeters only allow one to know the accumulated occupational doses during a certain period of time. This information is not enough to identify if there is a lack of occupational radiation protection during some procedures. This paper describes the use of a dose management system (DMS) allowing patient and occupational doses for individual procedures to be audited.

METHODS

The DMS manages patient and occupational doses measured by electronic personal dosimeters. One dosemeter located at the C-arm is used as a reference for scatter radiation. Data have been collected from five interventional rooms. Dosimetry data can be managed for the whole procedure and the different radiation events. Optimisation is done through auditing different sets of parameters for individual procedures: patient dose indicators, occupational dose values, the ratio between occupational doses, and the doses measured by the reference dosemeter at the C-arm, and the ratio between occupational and patient dose values.

RESULTS

The managed data correspond to the year 2021, with around 4500 procedures, and 8000 records on occupational exposures. Patient and staff dose data (for 11 cardiologists, 7 radiologists and 8 nurses) were available for 3043 procedures. The DMS allows alerts for patient dose indicators and occupational exposures to be set.

CONCLUSIONS

The main advantage of this integrated approach is the capacity to improve radiation safety for patients and workers together, auditing alerts for individual procedures.

ADVANCES IN KNOWLEDGE

The management of patient and occupational doses together (measured with electronic personal dosimeters) for individual interventional procedures, using dose management systems, allows alerting optimisation on high-dose values for patients and staff.

Occupational radiation dose from gastrointestinal endoscopy procedures with special emphasis on eye lens doses in endoscopic retrograde cholangiopancreatography

Background and study aims  Endoscopic retrograde cholangiopancreatography (ERCP) procedures may result in remarkable radiation doses to patients and staff. The aim of this prospective study was to determine occupational exposures in gastrointestinal endoscopy procedures, with a special emphasis on eye lens dose in ERCP. Methods  Altogether 604 fluoroscopy-guided procedures, of which 560 were ERCPs belonging to four American Society for Gastrointestinal Endoscopy procedural complexity levels, were performed using two fluoroscopy systems. Personal deep-dose equivalent H _p (10), shallow-dose equivalent H _p (0.07), and eye lens dose equivalent H _p (3) of eight interventionists and H _p (3) for two nurse dosimeters were measured. Thereafter, conversion coefficients from kerma-area product (KAP) for H _p (10), H _p (0.07), and H _p (3) were determined and dose equivalents per procedure to an operator and assisting staff were estimated. Further, mean conversion factors from H _p (10) and H _p (0.07) to H _p (3) were calculated. Results  The median KAP in ERCP was 1.0 Gy·cm ² , with mobile c-arm yielding higher doses than a floor-mounted device ( P  < 0.001). The median H _p (3) per ERCP was estimated to be 0.6 µSv (max. 12.5 µSv) and 0.4 µSv (max. 12.2 µSv) for operators and assisting staff, respectively. The median H _p (10) and H _p (0.07) per procedure ranged from 0.6 to 1.8 µSv. ERCP procedural complexity level ( P  ≤ 0.002) and interventionist ( P  < 0.001) affected dose equivalents. Conclusions  Occupational dose limits are unlikely to be exceeded in gastrointestinal endoscopy practice when following radiation-hygienic working methods and focusing on dose optimization. The eye lens dose equivalent H _p (3) may be estimated with sufficient agreement from the H _p (10) and H _p (0.07).

Adding interactive face-to-face lectures to passive lectures effectively reduces radiation exposure during atrial fibrillation ablation

BACKGROUND

Radiation exposure remains a major concern for electrophysiologists and patients. This study aimed to investigate the effect of altering awareness of radiation exposure during atrial fibrillation ablation using interactive face-to-face (FTF) lectures compared to passive lectures.

METHODS

Patients who underwent their first catheter ablation with radiofrequency energy for atrial fibrillation between January 2014 and December 2020 were included in this study. All operators attended an e-learning lecture on radiation exposure before catheter ablation. The addition of FTF lectures to this lecture was introduced in 2018. The effect on radiation exposure was compared between the pre-FTF and FTF periods by comparing fluoroscopy time and radiation dose.

RESULTS

A total of 896 patients [mean age, 66 ± 11 years; 603 men (67 %)] were included in this study. For pre-FTF (n = 345), only pulmonary vein isolation (PVI) was performed in 112 patients and PVI with additional ablation in 233 patients. For FTF lectures (n = 551), PVI-only was performed in 302 patients and PVI with additional ablation in 249 patients. Fluoroscopy time, cumulative air kerma, and cumulative air kerma per time significantly reduced after FTF introduction in both PVI-only group [pre-FTF and FTF; 37 ± 15 min and 16 ± 10 min (p < 0.0001), 477 ± 582 mGy and 108 ± 156 mGy (p < 0.0001), 11 ± 12 mGy/min, and 5 ± 6 mGy/min (p < 0.0001), respectively] and PVI with additional ablation group [pre-FTF and FTF; 48 ± 17 min and 15 ± 13 min (p < 0.0001), 613 ± 483 mGy and 68 ± 96 mGy (p < 0.0001), 12 ± 10 mGy/min, and 4 ± 4 mGy/min (p < 0.0001), respectively]. There were no significant differences in intraoperative complications between the two periods.

CONCLUSIONS

FTF lectures can reduce radiation exposure.

The Impact of Robotic Fractionated Radiotherapy for Benign Tumors of Parasellar Region on the Eye Structure and Function

PURPOSE

To evaluate the radiation effect of fractionated robotic radiotherapy of benign tumors located in the parasellar region on the anterior and posterior segments of the eye.

METHODS

A prospective observational study based on the expanded ophthalmological examination. The pre-treatment baseline was used as a control for the post-radiotherapy follow-up examinations. The study group consists of 34 patients (68 eyes) irradiated using the CyberKnife system. There were ten patients with cavernous sinus meningioma, nine with pituitary adenoma, five with meningioma of the anterior and middle cranial fossa, five with meningioma in the region close to optic chiasm, three with craniopharyngioma, and two with meningioma of the orbit. All patients were treated using three fractions of 600-800 cGy. We assessed the impact of radiation on the eye based on changes in anatomical and functional features. The condition of the eye surface, central corneal thickness (CCT), endothelial cell density (ECD), lens densitometry, central macular thickness (CMT), and retinal nerve fiber layer (RNFL) were the anatomical features assessed. The functional tests were best-corrected visual acuity (BCVA), intraocular pressure (IOP), visual field (VF) and visual-evoked potentials (VEP). An ophthalmologic examination was performed before and 6, 12, 18, and 24 months after radiotherapy.

RESULTS

We did not observe any significant changes in BCVA, IOP, CCT, CMT, VF, and VEP, nor in the slit-lamp examination during the two-years observation. We found a significant decrease in ECD at all follow-up measurements. The drop in ECD exceeded approximated age-related physiological loss. The reduction in ECD was not large enough to disrupt corneal function and thus affect vision. We also observed a statistically significant reduction of RNFL in all observation time points. However, there was no correlation between the dose delivered to the optic pathway and the decrease in RNFL thickness. The thinning of the RNFL was not significant enough to impair visual function.

CONCLUSION

Fractionated robotic radiotherapy of the tumors located close to the optical pathway is safe and does not impair patient's vision. Minor changes found in optic nerve anatomy (RNFL thinning) might be related to radiation effect or tumor compression. The causal relation between low doses of radiation delivered to the cornea and the observed significant but slight decrease in ECD is uncertain. The observed changes did not cause visual disturbances perceivable by the patients.

Surgeon eye lens dose monitoring in interventional neuroradiology, cardiovascular and radiology procedures

PURPOSE

This study investigated the radiation dose to surgeon eye lens for single procedure and normalised to exposure parameters for eight selected neuroradiology, cardiovascular and radiology interventional procedures.

METHODS

The procedures investigated were diagnostic study, Arteriovenous Malformations treatment (AVM) and aneurysm embolization for neuroradiology procedures, Coronary Angiography and Percutaneous Transluminal Coronary Angioplasty (CA-PTCA), Pacemaker and Implantable Cardioverter-Defibrillator implantation (PM-ICD), Endovascular Aortic Repair (EVAR) and Fenestrated Endovascular Aortic Repair (FEVAR) for cardiovascular and electrophysiology procedures. CT-guided lung biopsy was also monitored. All procedures were performed with table-mounted and ceiling-suspended shields (0.5 mm lead equivalent thickness), except for FEVAR and PM-ICD where only a table mounted shield was present, and CT-guided lung biopsy where no shield was used. Dose assessment was performed using a dosemeter positioned close to the most exposed eye of the surgeon, outside the protective eyewear.

RESULTS

The surgeon most exposed eye lens median H_p(3) equivalent dose for a single procedure, without protective eyewear contribution, was 18 μSv for neuroradiology diagnostic study, 62 μSv for AVM, 38 μSv for aneurysm embolization, 33 μSv for CA-PTCA, 39 μSv for PM-ICD, 49 μSv for EVAR, 2500 μSv for FEVAR, 153 μSv for CT-guided lung biopsy.

CONCLUSIONS

In interventional procedures, the 20 mSv/year dose limit for surgeon eye lens exposure might be exceeded if shields or protective eyewear are not used. Surgeon eye lens doses, normalised to single procedures and to exposure parameters, are a valuable tool for determining appropriate radiation protection measures and dedicated eye lens dosemeter assignment.

Feasibility study of computational occupational dosimetry: evaluating a proof-of-concept in an endovascular and interventional cardiology setting

Individual monitoring of radiation workers is essential to ensure compliance with legal dose limits and to ensure that doses are As Low As Reasonably Achievable. However, large uncertainties still exist in personal dosimetry and there are issues with compliance and incorrect wearing of dosimeters. The objective of the PODIUM (Personal Online Dosimetry Using Computational Methods) project was to improve personal dosimetry by an innovative approach: the development of an online dosimetry application based on computer simulations without the use of physical dosimeters. Occupational doses were calculated based on the use of camera tracking devices, flexible individualised phantoms and data from the radiation source. When combined with fast Monte Carlo simulation codes, the aim was to perform personal dosimetry in real-time. A key component of the PODIUM project was to assess and validate the methodology in interventional radiology workplaces where improvements in dosimetry are needed. This paper describes the feasibility of implementing the PODIUM approach in a clinical setting. Validation was carried out using dosimeters worn by Vascular Surgeons and Interventional Cardiologists during patient procedures at a hospital in Ireland. Our preliminary results from this feasibility study show acceptable differences of the order of 40% between calculated and measured staff doses, in terms of the personal dose equivalent quantity H_p(10), however there is a greater deviation for more complex cases and improvements are needed. The challenges of using the system in busy interventional rooms have informed the future needs and applicability of PODIUM. The availability of an online personal dosimetry application has the potential to overcome problems that arise from the use of current dosimeters. In addition, it should increase awareness of radiation protection among staff. Some limitations remain and a second phase of development would be required to bring the PODIUM method into operation in a hospital setting. However, an early prototype system has been tested in a clinical setting and the results from this two-year proof-of-concept PODIUM project are very promising for future development.

Radiation induced cataracts in interventionalists occupationally exposed to ionising radiation

BACKGROUND

Occupational exposure to ionising radiation may have detrimental health effects. Longer and more complex fluoroscopic procedures have placed interventionalists at increased occupational health risks especially for developing cataracts in the radiosensitive lenses of the eyes.

OBJECTIVES

This study aimed to determine the prevalence of occupational related cataracts and describe the risk factors for cataracts in occupationally exposed interventionalists compared with unexposed doctors.

METHOD

A cross-sectional study using multiple methods. A survey was conducted. The radiation workload was determined based on a self-administered questionnaire and dose area product values determined in previous studies. Both groups had slit lamp examinations. The data were analysed analytically using R software version 9.3.

RESULTS

The study included 98 interventionalists. The combined prevalence of posterior sub-capsular (PSC) and cortical cataracts was 18.8% in the exposed and 13.9% in the unexposed group. The prevalence of PSC cataracts in the exposed group was 5.9% and 2.8% in the unexposed group, with an odds ratio (OR) of 2.2 (95% confidence interval [CI]: 0.58; 8.61). Posterior sub-capsular cataracts were more common in the left eye. The increase in cataracts was not statistically significant in the exposed group but is of clinical significance.

CONCLUSION

The findings are important as they highlight the need for greater vigilance for protecting the radiation healthcare workforce in a developing country setting.

CONTRIBUTION

The research is the first of its kind in South Africa and Africa and contributes to determining the prevalence in this highly skilled and occupationally vulnerable group.

Transseptal puncture during catheter ablation associated with higher radiation exposure

BACKGROUND

Electroanatomic mapping systems are increasingly used during ablations to decrease the need for fluoroscopy and therefore radiation exposure. For left-sided arrhythmias, transseptal puncture is a common procedure performed to gain access to the left side of the heart. We aimed to demonstrate the radiation exposure associated with transseptal puncture.

METHODS

Data were retrospectively collected from the Catheter Ablation with Reduction or Elimination of Fluoroscopy registry. Patients with left-sided accessory pathway-mediated tachycardia, with a structurally normal heart, who had a transseptal puncture, and were under 22 years of age were included. Those with previous ablations, concurrent diagnostic or interventional catheterisation, and missing data for fluoroscopy use or procedural outcomes were excluded. Patients with a patent foramen ovale who did not have a transseptal puncture were selected as the control group using the same criteria. Procedural outcomes were compared between the two groups.

RESULTS

There were 284 patients in the transseptal puncture group and 70 in the patent foramen ovale group. The transseptal puncture group had a significantly higher mean procedure time (158.8 versus 131.4 minutes, p = 0.002), rate of fluoroscopy use (38% versus 7%, p < 0.001), and mean fluoroscopy time (2.4 versus 0.6 minutes, p < 0.001). The acute success and complication rates were similar.

CONCLUSIONS

Performing transseptal puncture remains a common reason to utilise fluoroscopy in the era of non-fluoroscopic ablation. Better tools are needed to make non-fluoroscopic transseptal puncture more feasible.

PATIENT AND STAFF DOSES FOR VARIOUS INTERVENTIONAL RADIOLOGY AND CARDIOLOGY EXAMINATIONS IN TURKEY

This study aims to determine the radiation doses of patients and staff during different interventional radiology and cardiology examinations. Dose measurements for interventional radiology examinations were performed in Ibn-i Sina Hospital of Ankara University using Siemens Artis-Zee medical imaging system. Patient dose measurement was carried out for interventional cardiology examinations in Cardiology Department of TOBB-ETU University, Medical Faculty Hospital using Philips Allura Centron interventional X-ray system. Patient doses were obtained in terms of kerma area product (KAP) and cumulative air kerma (CAK) from KAP meter attached to the angiography system. Performance tests of the angiography system were performed before patient dose measurements. Staff dose measurements were carried out with thermoluminescence dosimeters (TLD-100) placed in certain areas on the staff. Patient dose measurements were performed for 15 different interventional radiology examinations on a total of 431 patients and for four different cardiology examinations on a total of 299 patients. Monte Carlo based PCXMC 2.0 program was used to calculate patient effective doses. Lower extremity arteriography was the most common examination with a mean KAP value of 30 Gy cm2 and mean effective dose value of 1.2 mSv for total number of 194 patients. Mean KAP values calculated for coronary angiography, percutaneous coronary intervention, electrophysiological procedures and radiofrequency cardiac ablation examinations were 62.8, 162.8, 16.7 and 70.6 Gy cm2, respectively. Radiologist, nurse and technician effective dose normalised to the unit KAP of patient dose were 0.15, 0.11 and 0.14 μSv Gy-1 cm-2. Similarly, cardiologist, nurse and technician effective dose normalised to the unit KAP of patient dose were 0.22, 0.15 and 0.09 μSv Gy-1 cm-2. Measured KAP and CAK values vary depending on the type and complexity of the examination. The measured staff doses during cardiac examinations were higher when compared with that measured for interventional radiology as expected.

Uncertainties in occupational eye lens doses from dosimeters over the apron in interventional practices

It is relevant to estimate the uncertainties in the measurement of eye lens doses from a personal dosimeter over the protective apron without using additional dosimetry near the eyes. Additional dosimetry for interventionists represents a difficulty for routine clinical practice. This study analyses the estimated eye doses from dosimeter values taken at chest level over the apron and their uncertainties. Measurements ofH_p(0.07) using optically stimulated luminescence dosimeters located on the chest over the apron and on the glasses (in the inner and outer part of the protection) were taken from ten interventionalists in a university hospital, in the period 2018-2019 during standard clinical practice. For a total sample of 133 interventional procedures included in our study, the ratio between theH_p(0.07) on the glasses (left-outer side) and on the chest over the apron had an average of 0.74, with quartiles of 0.47, 0.64, 0.88. Statistically significant differences were found among operators using the U-Mann-Whitney test. The average transmission factor for the glasses was 0.30, with quartiles of 0.21, 0.25, and 0.32. Different complexity in the procedures, in the quality of the scatter radiation and in the individual operational practices, involve a relevant dispersion in the results for lens dose estimations from the over apron dosimeter. Lens doses may be between a 64% and an 88% of the over apron dosimeter values (using median or 3rd quartile). The use of 88% may be a conservative approach.

Improved Radiation Exposure Monitoring of Orthopaedic Residents After Institution of a Personalized Lead Protocol

Background:

Radiation exposure of orthopaedic residents should be accurately monitored to monitor and mitigate risk. The purpose of this study was to determine whether a personalized lead protocol (PLP) with a radiation monitoring officer would improve radiation exposure monitoring of orthopaedic surgery residents.

Materials and Methods:

This was a retrospective case-control study of 15 orthopaedic surgery residents monitored for radiation exposure during a 2-year period (March 2017 until February 2019). During the first 12-month period (phase 1), residents were given monthly radiation dosimeter badges and instructed to attach them daily to the communal lead aprons hanging outside the operating rooms. During the second 12-month period (phase 2), a PLP (PLP group) was instituted in which residents were given lead aprons embroidered with their individual names. A radiation safety officer was appointed who placed the badges monthly on all lead aprons and collected them at the end of the month, whereas faculty ensured residents wore their personalized lead apron. Data collected included fluoroscopy use time and radiation dosimeter readings during all orthopaedic surgeries in the study period.

Results:

There were 1,252 orthopaedic surgeries using fluoroscopy during phase 1 in the control group and 1,269 during phase 2 in the PLP group. The total monthly fluoroscopy exposure time for all cases averaged 190 minutes during phase 1 and 169 minutes during phase 2, with no significant difference between the groups (p < 0.45). During phase 1, 73.1% of the dosimeters reported radiation exposure, whereas during phase 2, 88.7% of the dosimeters reported radiation exposure (p < 0.001). During phase 1, the average monthly resident dosimeter exposure reading was 7.26 millirems (mrem) ± 37.07, vs. 19.00 mrem ± 51.16 during phase 2, which was significantly higher (p < 0.036).

Conclusions:

Institution of a PLP increased the compliance and exposure readings of radiation dosimeter badges for orthopaedic surgery residents, whereas the actual monthly fluoroscopy time did not change. Teaching hospitals should consider implementing a PLP to more accurately monitor exposure.

Level of Evidence:

3.

Radiation Protection in Interventional Radiology/Cardiology-Is State-of-the-Art Equipment Used?

Interventional radiology/cardiology is one of the fields with the highest radiation doses for workers. For this reason, the International Commission on Radiological Protection (ICRP) published new recommendations in 2018 to shield staff from radiation. This study sets out to establish the extent to which these recommendations are observed in Germany. For the study, areas were selected which are known to have relatively high radiation exposure along with good conditions for radiological protection-interventional cardiology, radiology and vascular surgery. The study was advertised with the aid of an information flyer which was distributed via organisations including the German Cardiac Society (Deutsche Gesellschaft für Kardiologie- Herz- und Kreislaufforschung e. V.). Everyone who participated in our study received a questionnaire to record their occupational medical history, dosimetry, working practices, existing interventional installations and personal protective equipment. The results were compared with international recommendations, especially those of the ICRP, based on state-of-the-art equipment. A total of 104 respondents from eight German clinics took part in the survey. Four participants had been medically diagnosed with cataracts. None of the participants had previously worn an additional dosimeter over their apron to determine partial-body doses. The interventional installations recommended by the ICRP have not been fitted in all examination rooms and, where they have been put in place, they are not always used consistently. Just 31 participants (36.6%) stated that they "always" wore protective lead glasses or a visor. This study revealed considerable deficits in radiological protection-especially in connection with shielding measures and dosimetric practices pertaining to the head and neck-during a range of interventions. Examination rooms without the recommended interventional installations should be upgraded in the future. According to the principle of dose minimization, there is considerable potential for improving radiation protection. Temporary measurements should be taken over the apron to determine the organ-specific equivalent dose to the lens of the eye and the head.

PERFORMANCE TESTING OF EYE LENS DOSEMETER AND EVALUATION OF PERSONAL RADIOLOGICAL EXPOSITION AT DOUERA ORTHOPEDIC INTERVENTIONAL SERVICE

The radiological monitoring of the eye in the workplace depends on the type of dosemeter used and its performance. The dosimetric performances of Nuclear Research Center of Algiers (CRNA) developed eye lens dosemeter (Larabi-Harfouche et al. Characterization and qualification of a CRNA eye dosemeter. Perspect Sci. 12, 100402 (2019)) are investigated in this work in order to assess its ability to measure the operational quantity Hp(3) in photon fields and to check its compliance with the International Commission on Radiological Protection recommendations for professionally exposed people (ICRP. ICRP statement on tissue reactions/early and late effects of radiation in normal tissues and organs - threshold doses for tissue reactions in a radiation protection context. ICRP Publication 118. Ann. ICRP 41(1/2) (2012)). Some key performance indicators including the relative response of the nonlinearity, coefficient of variation, and photon energy and angular dependence are assessed before the use of this dosemeter for eye lens monitoring of orthopedic staff in the operating room at Douera hospital. The monitoring results of this first pilot study are presented and discussed in view of supporting the recommendations of the International Organization for Standardization 15382: 2015 concerning the monitoring of the dose at lens.

Assessment of eye doses to staff involved in interventional cardiology procedures in Kuwait

In this study, which is the first of its kind in the gulf region, eye doses of interventional cardiologists and nurses were measured using active dosimeters for left and right eyes, in 60 percutaneous coronary interventions in three main hospitals in Kuwait. The dose given in terms of H_p(0.07) per procedure when ceiling suspended screens were used by main operators ranged from 18.5 to 30.3 µSv for the left eye and from 12.6 to 23.6 µSv for the right eye. Taking into account typical staff workload, the results show that the dose limit of 20 mSv/year to the eyes can be exceeded for interventional cardiologists in some situations, which demonstrates the need of using additional effective radiation protection tools, e.g. protective eye spectacles, in addition to the regular and proper use of ceiling suspended screens. With indications of increase in workload, the need for availability of a dedicated active dosimeter for the regular monitoring of eye doses is emphasized.

High Incidence of Cataracts in the Follow-Up of Patients Undergoing Percutaneous Coronary Intervention for Chronic Coronary Total Occlusion

Development of cataracts is a well-known adverse effect of ionizing radiation, but little information is available on their incidence in patients after other medical procedures, such as cardiac catheterizations. The study objective was to determine the incidence of cataracts in a cohort of patients undergoing percutaneous coronary intervention (PCI) for chronic coronary total occlusion (CTO) and its association with radiation dose. The study analyzed the incidence of cataracts during the follow-up of 126 patients who underwent chronic total coronary PCI, using Cox regression to identify predictive factors of cataract development. The study included 126 patients, 86.9% male, with a mean age of 60.5 years (range, 55.0-68.0 years). Twenty-three (18.2% n = 23) developed cataracts during a mean follow-up of 49.5 months (range 37.3-64.5 months). A higher incidence was observed in patients who received more than 5 Gy (29.0% vs. 14.7%, Hazard ratio (HR = 2.84 [1.19-6.77]). Multivariate analysis revealed a relationship between cataract development during the follow-up and a receipt of radiation dose >5 Gy (HR = 2.60, 95% confidence interval [CI 1.03-6.61]; p = 0.03), presence or history of predisposing eye disease (HR = 4.42, CI:1.57-12.40), diabetes (HR = 3.33 [1.22-9.24]), and older age, as in >57 (HR, 6.40 [1.81-22.61]). An elevated incidence of cataracts was observed in patients after PCI for CTO. The onset of cataracts is related to the radiation dose during catheterization, which is a potentially avoidable effect of which operators should be aware.

Eye protection in interventional procedures

Data suggest that radiation-induced cataracts may form without a threshold and at low-radiation doses. Staff involved in interventional radiology and cardiology fluoroscopy-guided procedures have the potential to be exposed to radiation levels that may lead to eye lens injury and the occurrence of opacifications have been reported. Estimates of lens dose for various fluoroscopy procedures and predicted annual dosages have been provided in numerous publications. Available tools for eye lens radiation protection include accessory shields, drapes and glasses. While some tools are valuable, others provide limited protection to the eye. Reducing patient radiation dose will also reduce occupational exposure. Significant variability in reported dose measurements indicate dose levels are highly dependent on individual actions and exposure reduction is possible. Further follow-up studies of staff lens opacification are recommended along with eye lens dose measurements under current clinical practice conditions.

Occupational hazard of fluoroscopy: An invisible threat to orthopaedic surgeons

The use of fluoroscopy is widespread within different medical specialties. Improper protection may cause significant radiation hazard to medical personnel. To evaluate the concepts on radiation safety and fluoroscopy use among orthopaedic surgeons and to reflect our current training on this issue, a survey was distributed to perform an audit in our department, an academic unit. Twenty-eight orthopaedic surgeons replied. Amongst our participants, 96.4% used a lead apron at all times. Only 33% used a thyroid shield, 67% never used radiation goggles and 96% never used radiation protection gloves. 53.6% and 46.4% of participants position the fluoroscopy incorrectly in the anteroposterior and lateral positions, respectively, during use. There is clearly a need for improved safety amongst orthopaedic surgeons. A literature review was further performed, showing the hazards of fluoroscopy for doctors, including the risk of cataracts, radiation dermatitis, skin cancer and thyroid cancer. Hazards specific to females, including breast cancer risk, and in-utero irradiation of foetus were also thoroughly discussed. Recommendations towards radiation safety and practical measures to reduce fluoroscopy radiation hazard during procedure were made. Education and training to doctors on this invisible hazard is strongly advised.

Self-reported radiation safety behaviors among veterinary specialists and residents performing fluoroscopic procedures on small animals

OBJECTIVE

To describe the radiation safety behaviors of veterinary specialists performing small animal fluoroscopic procedures and examine potential risk factors for these behaviors, including knowledge of radiation risk and training regarding machine operating parameters.

SAMPLE

197 veterinary specialists and residents in training.

PROCEDURES

An electronic questionnaire was distributed to members of the American Colleges of Veterinary Internal Medicine (subspecialties of cardiology and small animal internal medicine), Veterinary Radiology, and Veterinary Surgery.

RESULTS

The overall survey response rate was 6% (240/4,274 email recipients). Of the 240 respondents, 197 (82%) had operated an x-ray unit for a small animal fluoroscopic procedure in the preceding year and fully completed the questionnaire. More than 95% of respondents believed that radiation causes cancer, yet approximately 60% of respondents never wore hand or eye protection during fluoroscopic procedures, and 28% never adjusted the fluoroscopy machine operating parameters for the purpose of reducing their radiation dose. The most common reasons for not wearing eye shielding included no requirement to wear eyeglasses, poor fit, discomfort, and interference of eyeglasses with task performance. Respondents who had received training regarding machine operating parameters adjusted those parameters to reduce their radiation dose during procedures significantly more frequently than did respondents who had not received training.

CONCLUSIONS AND CLINICAL RELEVANCE

On the basis of the self-reported suboptimal radiation safety practices among veterinary fluoroscopy users, we recommend formal incorporation of radiation safety education into residency training programs. All fluoroscopy machine operators should be trained regarding the machine operating parameters that can be adjusted to reduce occupational radiation exposure.

Evaluation of a suspended radiation protection system to reduce operator exposure in cardiology interventional procedures

OBJECTIVES

To investigate a novel suspended radiation shield (ZG), in reducing operator radiation exposure during cardiology interventions.

BACKGROUND

Radiation exposure to the operator remains an occupational health hazard in the cardiac catheterization laboratory.

METHODS

An anthropomorphic mannequin simulating an operator was placed near a phantom, simulating a patient. To measure the operator dose reduction, thermoluminescent detectors (TLDs) were inserted into the head and into the eye bulbs of the mannequin, while electronic dosimeters were positioned on the temple and at the level of the thyroid. Measurements were performed without and with the ZG system in place. Physician exposure was subsequently prospectively measured on the torso, on the left eye and on upper arm using the same electronic dosimeters, during clinical procedures (coronary angiography (CA) and percutaneous coronary intervention (PCI)). The physicians dose reduction was assessed by comparing operator dose when using traditional radioprotection garments (Phase 0) versus using the ZG system (Phase 1).

RESULTS

Dose reductions as measured on the mannequin ranged from 66% to the head, to 100% to the torso. No dose was detected at the level of the torso and thyroid with ZG. When comparing CA and PCI procedures between Phase 0 and Phase 1, a significant difference (p < 0.001) was found for the left eye and the left wrist. Dose reduction as measured during clinical procedures for left eye/upper arm were on average 78.9%/95.6% for CA and 83.0%/93.0% for PCI, respectively (p < 0.001 for both).

CONCLUSIONS

The ZG systems has a great potential to significantly reduce operator dose through the creation of a nearly zero-radiation work environment.

Managing occupational doses with smartphones in interventional radiology

Purpose

This study presents a prototype smartphone application for occupational dosimetry in interventional practices based on electronic personal dosimeters to assist in dose monitoring.

Methods

The prototype receives and records information from the occupational dose report containing the cumulative dose of electronic personal dosimeters worn over the apron at chest level and electronic area dosimeters located on C‐arms (reference dosimeters), for each fluoroscopy‐guided procedure. Using their smartphones, personnel involved in interventional practices can review and compare their occupational records with an investigation level, the dose limits, and their department colleagues (anonymously). The ratio between H_p(10) measured by the personal and the reference dosimeters at the C‐arm is presented as an indicator of consistent use of suspended operator shield. Some general results extracted from the first months of use are presented.

Results

The reference dosimeter located at the C‐arm (without lead protection and acting as an ambient dosimeter) recorded in one of the laboratories 217 mSv during 308 procedures over 5 months, showing an indication of the radiation risk present in an interventional laboratory. The ratio between the personal cumulative dose and the dose at a reference C‐arm dosimeter ranged from 0.2% to 1.67% (a factor of 8.5) for different interventionalists. These differences suggest different protection habits among interventional operators, as well as a target for dose reduction.

Conclusions

With this system, professionals have easy access to their occupational dosimetry records (including information on the workload) in the setting of their interventional departments, to thereby actively engage in the protection process.

Are X-ray Safety Glasses Alone Enough for Adequate Ocular Protection in Complex Radiological Interventions?

ABSTRACT

The maximum annual radiation ocular dose limit for medical staff has been reduced to 20 mSv in the current European directive 2013/59/Euratom. This multi-centric study aims at reporting the protected and unprotected eye lens doses in different fluoroscopically guided interventions and to evaluate any other factors that could influence the ocular dose. From July 2018 to July 2019, ocular radiation doses of six interventionists of four departments during complex interventions were recorded with a thermoluminescent dosimeter in front of and behind radiation protection glasses to measure the protected and unprotected doses. The position of personnel, intervention type, fluoroscopy time, total body dose and use of pre-installed protection devices like lead acrylic shields were also systematically recorded. Linear regression analysis was used to estimate the doses at 2 y and 5 y. The annual unprotected/protected ocular doses of six interventionists were 67/21, 32.7/3.3, 27.4/5.1, 7/0, 21.8/2.2, and 0/0 mSv, respectively. The unprotected dose crossed the 20-mSv annual limits for four interventionists and protected dose for one less experienced interventionist. The estimated 5-y protected ocular dose of this interventionist was 101.318 mSv (95%CI 96.066-106.57), also crossing the 5-y limit. The use of a lead acrylic shield was observed to have a significant effect in reducing ocular doses. The annual unprotected and protected ocular doses for interventionists dealing with complex interventions could cross the present permitted yearly limit. The measurement of significant protected ocular dose behind the radiation protection glasses emphasizes the additional indispensable role of pre-installed radiation protection devices and training in reducing radiation doses for complex procedures.

Latest Developments in Robotic Percutaneous Coronary Intervention

Interventional cardiovascular medicine has seen constant progress over the last few decades. Since the first angiograms and percutaneous transluminal coronary angioplasty were carried out, this progress has been tremendous and has led to a substantial decline in cardiovascular morbidity and mortality. The purpose of this article is to report and review the latest developments and evidence in robotics-assisted percutaneous coronary intervention (rPCI) and its potential future applications, opportunities, and limitations. Contemporary evidence shows that rPCI can lead to a significant reduction in radiation exposure as well as medical hazards for cardiologists. Rates of device and procedural success remain high and there is no evidence of a disadvantage for the patient. The accuracy of implantation with a reduced geographic mismatch is a further advantage that can result in a higher quality of treatment. Even in complex coronary lesions and procedures, rPCI seems to be safe and efficient. The latest developments include telestenting over hundreds of kilometers from a remote platform. Currently, the main limitations are the absence of large-scale randomized trials for the valid assessment of the benefits and disadvantages of rPCI as well as the technical limitations of the currently available rPCI systems. rPCI is a forward-looking innovation in cardiology that is applicable to a wide range of coronary interventions. Despite the present lack of knowledge and the limited data concerning the outcome for the patient, the available literature reveals promising results that should lead to improvements for physicians and patients.

Occupational doses to the eye lens in pediatric and adult noncardiac interventional radiology procedures

PURPOSE

To assess occupational lens exposure in a mixed interventional radiology department, comparing pediatric and adult procedures. To analyze the correlation between the lens dose and the doses measured at the chest and collar level and the kerma-area product (P_KA ).

METHODS

For 17 months, three radiologists performing both pediatric and adult interventions were monitored by means of 14 dosimeters per worker: 12 single-point optically stimulated luminescent (OSL) dosimeters calibrated in terms of H_p (0.07) were placed on the inside and outside of two pairs of lead glasses, one for pediatric procedures and one for adult interventions; another whole-body OSL dosimeter calibrated in terms of H_p (10) was placed over the thyroid shield; finally, an additional active solid-state dosimeter, also calibrated for H_p (10), was worn on the chest, over the apron. Furthermore, a database was created to register the demographic and dosimetric data of the procedures, as well as the name of the radiologist acting as first operator.

RESULTS

For the three radiologists, who performed 276-338 procedures/year (20% pediatric), cumulative annual doses to the left bare eye exceeded 20 mSv (21-61 mSv). Considering the glasses' protection, annual doses exceeded 6 mSv (13-48 mSv) for both eyes. No important differences were observed in lens dose per procedure between pediatric and adult interventions (0.16 vs 0.18, 0.12 vs 0.09, and 0.07 vs 0.07 mSv), although lens dose per P_KA was 4.1-4.5 times higher in pediatrics (5.8 vs 1.3, 3.3 vs 0.8, and 2.6 vs 0.6 µSv/Gy·cm² ) despite a similar use of the ceiling-suspended screen. Lens doses were highly correlated with collar readings (with Pearson coefficients [r] ranging from 0.86 to 0.98) and with chest readings (with r ranging from 0.75 to 0.93). However, slopes of the linear regressions varied greatly among radiologists.

CONCLUSIONS

There is real risk of exceeding the occupational dose limit to the eye lens in mixed interventional radiology rooms if radiation protection tools are not used properly. Regular monitoring of the lens dose is recommended, given lens exposure might easily exceed 6 mSv/yr. Using a collar dosimeter for this purpose might be suitable if it is preceded by an individualized regression analysis. The same radiation protection measures should be applied to interventional radiologists regardless of whether they are treating pediatric or adult patients.

Trends in Professional Radiation Exposures of Medical Staff Covered by Personal Dose Monitoring at a Rijeka Clinical Hospital Centre (2000 to 2015)

ABSTRACT

The increase in the number of radiological procedures observed in recent years also means greater exposure to ionizing radiation for the medical staff performing these procedures. This is most pronounced in the teams that perform interventional and invasive radiological procedures. The aim of this study was to examine the impact of increasing numbers of radiological procedures on the effective dose received by medical staff and to determine which professions received the highest exposure to ionizing radiation. Data for effective doses of 326 employees of Rijeka Clinical Hospital Centre covered by personal dosimetry in the period from 2000 to 2015 have been analyzed. Employees were divided by sex, by departments in which they were employed, and according to their professions. The analysis has shown that the exposure level of workers working in the ionizing radiation zone is typically well below the dose limits. During 2015, most employees (over 96.3%) received an annual effective dose of less than 0.1 mSv. Only three persons received an annual dose higher than 0.5 mSv, and one person received an annual dose of 6.9 mSv. Comparison of the radiation exposure doses of medical workers of different professions has shown that the highest dose of radiation is received by cardiologists involved in interventional cardiology procedures. Therefore, the additional need is to take care of their protection, check the manner of their work, and ensure more even workload of cardiologists participating in procedures that involve higher exposure to ionizing radiation.

Radiation exposure in cryoballoon ablation compared to radiofrequency ablation with three-dimensional electroanatomic mapping in atrial fibrillation patients

BACKGROUND

Catheter ablation for atrial fibrillation (AF) has become an established treatment to control symptoms. AF ablation either by cryoballoon or radiofrequency using three-dimensional (3D) electroanatomical mapping exposes patients and medical staff to increased doses of radiation.

AIM

To compare radiation exposure in patients during cryoballoon ablation compared to 3D electro-anatomic mapping catheter ablation in AF patients.

METHODS

A total of 30 patients referred for AF ablation underwent full history taking, 12-lead ECG, echocardiogram, and pulmonary vein isolation either by 3D mapping system or cryoballoon. Procedure duration and fluoroscopy time were collected and analyzed. Radiation exposure was measured using thermoluminescent dosimeters placed at different sites related to patients and medical staff.

RESULT

The procedural time was statistically significantly longer with 3D mapping compared to cryoballoon but showed no significant difference regarding fluoroscopy time. There was a significantly higher radiation skin dose at the right scapular area in the cryoballoon ablation group, in addition to higher peak skin dose compared to the 3D mapping ablation group. There was no statistically significant correlation between peak skin doses and fluoroscopy duration but a statistically significant correlation between peak skin dose and usage of high frame rate and the high dose area product.

CONCLUSION

Cryoballoon ablation was found to be associated with higher peak skin radiation doses especially in the right scapular area. Knowing dose area product and peak skin dose is more important than fluoroscopy time alone.

Orthopaedic Surgeon Brain Radiation During Fluoroscopy: A Cadaver Model

BACKGROUND

The aims of this study were to quantify exposure of the surgeon's brain to radiation during short cephalomedullary (SC) nailing, to extrapolate lifetime dose, and to determine the effects of personal protective equipment (PPE) on brain dose.

METHODS

Two cadaveric specimens were used: (1) a whole cadaveric body representing the patient, with a left nail inserted to act as the scatter medium, and (2) an isolated head-and-neck cadaveric specimen representing a surgeon, with radiation dosimeters placed in specific locations in the brain. The "patient" cadaver's left hip was exposed in posteroanterior and lateral radiographic planes. Measurements were performed without shielding of the head-and-neck specimen and then repeated sequentially with different PPE configurations. An average surgeon career was estimated to be 40 years (ages 25 to 65 years) with the caseload obtained from the department's billing data.

RESULTS

The mean radiation dose to the surgeon brain without PPE was 3.35 µGy (95% confidence interval [CI]: 2.4 to 4.3) per nail procedure. This was significantly reduced with use of a thyroid collar (2.94 µGy [95% CI: 1.91 to 3.91], p = 0.04). Compared with use of the thyroid collar in isolation, there was no significant additional reduction in radiation when the collar was used with leaded glasses (2.96 µGy [95% CI: 2.15 to 3.76], p = 0.97), with a lead cap (3.22 µGy [95% CI: 2.31 to 4.13], p = 0.55), or with both (2.31 µGy [95% CI: 1.61 to 3.01], p = 0.15). The extrapolated lifetime dose over 40 working years for SC nailing without PPE was 2,146 µGy (95% CI: 1,539 to 2,753), with an effective dose of 21.5 µSv.

CONCLUSIONS

The extrapolated cumulative lifetime radiation to a surgeon's brain from SC nailing based on our institution's workload and technology is low and comparable with radiation during a one-way flight from London to New York. Of note, we studied only one of many fluoroscopy-aided procedures and likely underestimated total lifetime exposure if exposures from other procedures are included. This study also demonstrates that thyroid collars significantly reduce brain dose for this procedure whereas other head/neck PPE such as lead caps appear to have minimal additional effect. This study provides a methodology for future studies to quantify brain dose for other common orthopaedic procedures.

CLINICAL RELEVANCE

This study, based on our institutional data, demonstrates that although the lifetime brain dose from SC nailing is low, thyroid collars significantly reduce this dose further. As such, in accordance with the "as low as reasonably achievable" radiation exposure principle, radiation safety programs and individual surgeons should consider use of thyroid collars in this setting.

Fluoroscopically-guided interventions with radiation doses exceeding 5000 mGy reference point air kerma: a dosimetric analysis of 89,549 interventional radiology, neurointerventional radiology, vascular surgery, and neurosurgery encounters

Purpose

To quantify and categorize fluoroscopically-guided procedures with radiation doses exceeding 5000 mGy reference point air kerma (K_a,r). K_a,r > 5000 mGy has been defined as a “significant radiation dose” by the Society of Interventional Radiology. Identification and analysis of interventions with high radiation doses has the potential to reduce radiation-induced injuries.

Materials and methods

Radiation dose data from a dose monitoring system for 19 interventional suites and 89,549 consecutive patient encounters from January 1, 2013 to August 1, 2019 at a single academic institution were reviewed. All patient encounters with K_a,r > 5000 mGy were included. All other encounters were excluded (n = 89,289). Patient demographics, medical specialty, intervention type, fluoroscopy time (minutes), dose area product (mGy·cm²), and K_a,r (mGy) were evaluated.

Results

There were 260 (0.3%) fluoroscopically-guided procedures with K_a,r > 5000 mGy. Of the 260 procedures which exceeded 5000 mGy, neurosurgery performed 81 (30.5%) procedures, followed by interventional radiology (n = 75; 28.2%), neurointerventional radiology (n = 55; 20.7%), and vascular surgery (n = 49; 18.4%). The procedures associated with the highest K_a,r were venous stent reconstruction performed by interventional radiology, arteriovenous malformation embolization performed by neurointerventional radiology, spinal hardware fixation by neurosurgery, and arterial interventions performed by vascular surgery. Neurointerventional radiology had the highest mean K_a,r (7,799 mGy), followed by neurosurgery (7452 mGy), vascular surgery (6849 mGy), and interventional radiology (6109 mGy). The mean K_a,r for interventional radiology performed procedures exceeding 5000 mGy was significantly lower than that for neurointerventional radiology, neurosurgery, and vascular surgery.

Conclusions

Fluoroscopically-guided procedures with radiation dose exceeding 5000 mGy reference point air kerma are uncommon. The results of this study demonstrate that a large proportion of cases exceeding 5000 mGy were performed by non-radiologists, who likely do not receive the same training in radiation physics, radiation biology, and dose reduction techniques as radiologists.

Risk of cataract in health care workers exposed to ionizing radiation: a systematic review

Background:

The eye is an important sensory organ occupationally exposed to ionizing radiation (IR) in healthcare workers (HCWs) engaged in medical imaging (MI). New evidence highlights the possible induction of cataract at IR exposure levels to be much lower than expected in the past.

Objective:

Conduct an updated review on the current evidence on cataract risk in healthcare workers exposed to IR.

Methods:

Published scientific studies on cataract risk in IR exposed healthcare workers were collected through a systematic search of two biomedical databases (MEDLINE and Scopus). Data from included studies was extracted and summarized. Study quality was also assessed.

Results:

All 21 eligible studies reported an increased prevalence of cataract, especially posterior subcapsular cataract, in IR exposed HCWs with a higher prevalence in interventional cardiology staff.

Discussion:

Our review synthesizes the latest evidence to support the hypothesis of a significantly increased risk of occupational cataract in healthcare workers operating MI and exposed to IR, especially in interventional cardiologists. Data also support a dose-response relationship between IR exposure and the prevalence of opacities, especially posterior subcapsular opacities.

Conclusions:

Findings highlight the need for effective control measures including appropriate training, adherence to protective procedures, and a constant use of shields and eye personal protective equipment in healthcare workers with optical exposure to IR. Periodic health surveillance programs, possibly including lens evaluation, are also important to monitor cataract risk in these MI operators.

The association between exposure to radiation and the incidence of cataract

OBJECTIVE

To examine the association between exposure to radiation from computed tomography (CT) studies and the incidence of cataract.

METHODS

In a nested case-control study, all cataract cases and their matched controls were sampled from a retrospective cohort of Israeli residents who underwent CT scans or ultrasonic tests in Soroka Medical Center, Beer-Sheva, Israel, between the years 1996 and 2014. The risk of cataract associated with head, neck or the rest of the body CT was assessed using Poisson survival analysis.

RESULTS

The nested matched sample included 3841 cataract cases and their age- and sex-matched controls (n = 228,743). CT radiation exposure was more frequent in the cataract group, with 9.7% head CT, 1.2% neck CT and 6.6% other CT, compared to 5%, 0.7% and 3.7% among person-years without cataract (p < 0.001). In a multivariate analysis, a similar increased risk of cataract associated with head (hazard ratio (HR): 1.24, 95% confidence interval (CI): 1.11; 1.38) and other CT (HR: 1.25, 95% CI: 1.10; 1.43) was found. No association with neck CT (HR: 1.07, 95% CI: 0.80; 1.43) was observed.

CONCLUSION

In our study population, a similar risk of cataract with head, neck or the rest of the body CT was detected.

Rogue cell-like chromosomal aberrations in peripheral blood lymphocytes of interventional radiologists: A case study

We report two cases of interventional radiologists who had been exposed to radiation while performing fluoroscopically-guided interventional procedures (FGIPs), mainly transcatheter arterial chemoembolization, percutaneous catheter drainage, and percutaneous transhepatic biliary drainage procedures, for over 10 years. They had a unique multi-aberrant cell type with not only high numbers of dicentrics and/or centric rings but also excess acentric double minutes, similar to a rogue cell. As revealed in a self-administered questionnaire, they wore personal dosimeters and protective equipment at all times and used shielding devices during interventional fluoroscopy procedures. However, the exposed dose levels derived from cytogenetic dosimetry were much higher than the doses recorded on their personal dosimeters. A large number of unstable and stable chromosomal aberrations that were found in the peripheral blood lymphocytes of these interventional radiologists might be due to repeated and long-term exposure to ionizing radiation while performing FGIPs. Further investigations of chromosomal aberrations in interventional radiologists may improve the understanding of the long-term effects of radiation exposure on medical personnel.

Calibration of the LiF - thermoluminescent detectors used for personal dose equivalent Hp(3) assessment

AIMS

The issue of exposure of eye lenses of employees exposed to ionizing radiation is an interesting topic not only from the point of view of deterministic effects related to the occurrence of cataracts, but also dosimetric aspects, in particular the calibration of detectors in units enabling the assessment of eye lens exposure or personal dose equivalent Hp(3). The paper presents the idea of calibrating thermoluminescent detectors designed for the Hp(3) values measurement of gamma radiation, which the source is the process of annihilation of positrons emitted by the deoxyglucose marker - ¹⁸F radionuclide.

METHODS

The method was based on the value of air kerma Ka to Hp(3) conversion coefficients (Hp(3,0°)/Ka) developed as part of the ORAMED project. High-sensitivity thermoluminescent detectors (MCP-N) produced in Poland were used in the measurements. During the exposure of the detectors, a ¹³⁷Cs gamma radiation source (irradiator ¹³⁷Cs/⁶⁰Co) and a 20cm diameter cylinder filled with water were used.

RESULTS & CONCLUSIONS

The value of conversion coefficient Hp(3,0°)/Ka for energy 511 keV is 1.31Sv/Gy and the calibration factor is (3.46±0.03)·10^-4 mSv/N (N - number of counts). Verification of the value of the obtained coefficient carried out using a cylinder with a diameter of 20cm showed a difference of less than 2% in relation to the value obtained by the method described in this paper.

A study of the underestimation of eye lens dose with current eye dosemeters for interventional clinicians wearing lead glasses

The reduction in the occupational dose limit of the eye lens has created the need for optimising eye protection and dose assessment, in particular for interventional clinicians. Lead glasses are one of the protection tools for shielding the eyes, but assessing the eye lens dose when these are in place remains challenging. In this study, we evaluated the impact of the position of H _p (3) dosemeters on the estimated eye lens dose when lead glasses are used in interventional settings. Using the Monte Carlo method (MCNPX), an interventional cardiology setup was simulated for two models of lead glasses, five beam projections and two patient access routes. H _p (3) dosemeters were placed at several positions on the operator and the obtained dose was compared to the dose to the sensitive part of the eye lens (H _lens). Furthermore, to reproduce an experimental setup, a reference dosemeter, H _p (3)_ref, was placed on the surface of the eye. The dose measured by H _p (3)_ref was, on average, only 60% of H _lens. Dosemeters placed on the glasses, under their shielding, underestimated H _lens for all parameters considered, by from 10% up to 90%. Conversely, dosemeters placed on the head or on the glasses, over their shielding, overestimated H _lens, on average, up to 60%. The presence or lack of side shielding in lead glasses affected mostly dosemeters placed on the forehead, at the left side. Results suggest that both use of a correction factor of 0.5 to account for the presence of lead glasses in doses measured outside their shielding and placing an eye lens dosemeter immediately beneath the lenses of lead glasses may lead to the underestimation of the eye lens dose. Most suitable positions for eye lens dose assessment were on the skin, unshielded by the glasses or close to the eye, with no correction to the dose measured.