Risk of cataract among interventional cardiologists and catheterization lab staff: A systematic review and meta-analysis

Safety and Efficacy of TEE Guidance in Electrophysiological Procedures Without Fluoroscopy

Background/Objectives: Fluoroscopy has traditionally supported three-dimensional (3D) electroanatomical mapping (EAM)-guided left atrial (LA) electrophysiological procedures (EPs), but the associated ionizing radiation poses long-term health risks for patients and healthcare professionals. Advances in 3D EAM systems now enable nearly or entirely radiation-free ablations. Imaging techniques such as transesophageal echocardiography (TEE) are increasingly used for precise and safe LA access. This study evaluates the safety and efficacy of TEE-guided, zero-fluoroscopy/near-zero-fluoroscopy LA EPs in routine clinical practice. Methods: 142 consecutive patients undergoing LA EAM-guided radiofrequency ablation at the Ulm University Heart Center between October 2023 and November 2024 were analyzed. In total, 73 patients underwent zero-fluoroscopy/near-zero-fluoroscopy ablation guided solely by TEE, while another 69 patients received fluoroscopy-guided ablation using TEE and fluoroscopy guidance. Results: Of the 142 patients, 58.0 (40.8%) were female, and the median age was 73.0 (64.0; 79.0) years. A total of 53 (37.3%) underwent zero-fluoroscopy EP, 20 (14.1%) underwent near-zero-fluoroscopy EP, and 69 (48.6%) underwent fluoroscopy-guided EP. Procedure duration was without significantly relevant difference between both groups (132.0 vs. 133.0 min; p = 0.52). Median radiation exposure in the zero-fluoroscopy/near-zero-fluoroscopy group was 0 (0.0; 0.0) minutes, compared to significantly higher values in the fluoroscopy group (9.7 (5.9; 15.3) minutes; p < 0.001). No significant differences in complications were observed (p = 0.09). Conclusions: TEE-guided, radiation-free LA EP offers a safe and effective approach, significantly reducing radiation exposure and its associated risks while maintaining high procedural efficacy without increasing the risk of complications.

Robot-Assisted Cardiovascular Interventions

Innovation has been the cornerstone of progress in the field of percutaneous coronary intervention (PCI) since its inception. Refinements in procedural technique and interventional tools have improved patient outcomes and overall safety. Despite this progress, however, the health risks posed to operators and staff remain undeniably high. Robotic PCI (R-PCI) offers a new era in coronary revascularization poised to address this dilemma. To date, R-PCI procedures have been widely performed in clinical practice for over a decade and multiple novel endovascular robotic systems are currently under development. This review serves as an up-to-date understanding of R-PCI, focusing on the origins, clinical evidence, current state, and future targets of robotic therapy.

Impact of X-Ray Protective Drapes on Operator and Patient Radiation Exposure During Cardiac Catheterization

BACKGROUND

As cardiac catheterization operators are exposed to radiation exposure throughout their careers, optimal radiation protection is crucial. Our study was designed to assess the effects of supplementary protective measures beyond standard radiation protection attire and barriers, measuring their influence on scatter radiation exposure levels for both the operator and the patient.

AIMS

The objective of this trial is to assess the impact of a lead shield on scatter radiation exposure for both the operator and the patient.

METHODS

We conducted a prospective, randomized clinical trial in which procedures were allocated to incorporate the use of a reusable lead apron designed to shield the lower body of the patient. Both operators and patients were outfitted with real-time procedure-specific dosimeters to monitor exposure. All patients undergoing radial access procedures were entered into a randomization process. The study's dual primary outcomes included the relative operator dose above (RODt) and under (RODu) the protective gear, as well as the scatter patient radiation dose (RPD), which was calculated as the measured radiation exposure (µSv) standardized against the dose area product (DAP).

RESULTS

Out of 400 procedures that were randomized, data from 346 procedures was complete for analysis. The use of the pelvic shield resulted in a substantial decrease in the RODt and RODu, with reductions of 25% and 40%, respectively (p < 0.0001). There was also a 38% reduction observed in the scatter RPD. In patients with a high BMI, the effectiveness of the pelvic shield varied.

CONCLUSION

Employing an auxiliary pelvic shield significantly diminishes scatter radiation exposure for both the operator and the patient.

Occupational exposures and age-related cataract: A review

Occupational exposures comprise of a broad range of factors in constant and direct contact with the ocular surface. Cataract, a leading cause of visual impairment globally, has been associated with various occupational exposures. This review critically examines existing literature on the relationship between occupational exposures and cataract development. We aim to synthesize findings from studies exploring the impact of occupational factors such as ultraviolet (UV) radiation, ionizing radiation, welding fumes, polyaromatic hydrocarbons, tobacco dust, and other elements on the prevalence and incidence of cataract among exposed populations. In our review, certain exposures, such as UV radiation, demonstrated strong evidence regarding their association with cataract development, while others presented suggestive evidence. Hence, further studies are needed to better understand exposures of greatest concern, which can subsequently inform regulations pertaining to occupational exposures in work environments.

In the era of transition from fiction to reality: Robotic-assisted neurointervention-a systematic review and meta-analysis

OBJECTIVE

In recent years, the application of robotic assistance in diagnostic and therapeutic endovascular neurointerventional procedures has gained notable attention. In this systematic review and meta-analysis, we aim to evaluate the feasibility, safety, and current indications of robotic-assisted neurointerventions and to assess the degree of robotic assistance and reasons for unplanned manual conversion from robotic assistance.

METHODS

We searched Medline, Scopus, Web of Science, and Cochrane Library databases following PRISMA guidelines and included studies with ≥ 4 patients reporting on robotic-assisted neurointerventions. We analyzed outcomes including technical success, manual conversion, procedure-related complications, morbidity, and mortality with a random-effects meta-analysis. We also identified causes of manual conversion and conducted subanalyses by procedure type and robotic system.

RESULTS

Thirteen studies, comprising 538 robotic-assisted neurointerventions, were included. Procedures were primarily diagnostic cerebral angiograms (n = 348), cerebral aneurysm embolizations (n = 127), and carotid artery stenting (n = 37). The CorPath GRX (Corindus) robotic system was employed in the majority of cases (n = 355). Across all studies, the technical success rate was 93%, and the procedure-related complication rate was 0.7%. Manual steps were necessary in all cases due to inherent procedural requirements. Unplanned manual conversion from robotic assistance was necessary in 7% of cases. Further analysis of failures identified challenging anatomies, loss of working length, and mechanical failures as the most common reasons.

CONCLUSIONS

This systematic review and meta-analysis found that, with a certain degree of manual assistance, robotic-assisted neurointervention is highly feasible, safe, and capable of performing DCA, CAS, and therapeutic neurointerventions that can be executed with a single microcatheter involving simple coiling, stent-assisted coiling, and flow diverter embolization. However, unplanned manual conversion is not uncommon. Improvements in working length and mechanical parts, including the cassette robotic arm and console, as well as CorPath GRX compatibility with 0.035-inch wires, may reduce the rates of manual conversion for current indications. Nonetheless, technical adaptations are essential to broaden the scope of therapeutic neurointervention indications.

Achieving reduced radiation exposure with maintained fluoroscopy effectiveness using ultralow-dose settings in cryoballoon ablation

Background and Aims

Optimization of fluoroscopic image quality for reducing radiation exposure in cryoballoon pulmonary vein isolation (CB-PVI) has not yet been fully investigated. Therefore, we tried to compare the radiation doses among three different X-ray system settings.

Methods

Consecutive 148 patients scheduled for their first CB-PVI were prospectively enrolled: low dose with the use of an anti-scatter grid for the first 51 patients (LD + G group), low dose without an anti-scatter grid for the subsequent 46 patients (LD-G group), and ultralow dose (ULD group) with an anti-scatter grid for the remaining 51 patients. We compared the radiation doses required to complete CB-PVI procedures among the groups. There were 27 patients for whom CB-PVI was performed without cine acquisition, but with fluoroscopy only, and the radiation doses were also compared.

Results

The median procedure time and fluoroscopy time were 119 and 35.5 min, respectively, with no significant differences among the groups. The median cumulative air Kerma (AK) decreased in both the LD-G group (71.8 mGy, p < .001) and the ULD group (73.0 mGy, p < .001), compared to the LD + G group (145.0 mGy). Among 27 patients who underwent CB-PVI without cine acquisition, the median cumulative AK further decreased in both the LD-G group (31.4 mGy, p < .05) and the ULD group (22.7 mGy, p < .01), compared to the LD + G group (64.6 mGy).

Conclusion

Using an ULD X-ray setting and avoiding cine acquisition, we can reduce radiation exposure, while ensuring the necessary fluoroscopy time for the CB-PVI procedure.

Radiation exposure and safety in low-dose CT-guided glycerol rhizotomy for trigeminal Neuralgia outside the operating room

BACKGROUND

Percutaneous rhizotomy of the Gasserian ganglion is a well-established intervention for patients suffering from refractory trigeminal pain, not amenable to pharmacological management or microvascular decompression. Traditionally conducted under fluoroscopic guidance using Hartel's technique, this study investigates a modified approach employing low-dose CT guidance to achieve maximal procedural precision and safety with the emphasis on minimizing radiation exposure.

METHODS

A retrospective analysis of patients undergoing percutaneous rhizotomy of the Gasserian ganglion at our institution was undertaken. Procedures were divided into fluoroscopy and CT-guided foramen ovale (FO) cannulation cohorts. Radiation doses were assessed, excluding cases with incomplete data. The study included 32 procedures in the fluoroscopy group and 30 in the CT group.

RESULTS

In the CT-guided group, the median effective dose was 0.21 mSv. The median number of CT scans per procedure was 4.5, and the median procedure time was 15 min. Successful FO cannulation was achieved in all 30 procedures (100%). In the fluoroscopy group, the median effective dose was 0.022 mSv, and the median procedure time was 15 min. Cannulation of FO was successful in 31 of 32 procedures (96.9%). The only complications in the CT-guided group were three minor cheek hematomas. Immediate pain relief in the CT-guided group was reported in 25 of 30 procedures (83.3%), 22 of 30 (73.3%) provided relief at one month, and 10 of 18 (55.6%) procedures resulting in pain relief at one month continued to provide relief after two years.

CONCLUSION

Low-dose CT-guided percutaneous rhizotomy conducted in the radiology suite carries negligible radiation exposure for patients and eliminates it for personnel. This method is fast, simple, precise, and carries a very low risk of complications.

Coil Embolization for Cerebral Aneurysm Using Low Pulse Rate Fluoroscopy

Although coil embolization is commonly perceived as a minimally invasive procedure, the associated radiation exposure cannot be disregarded. To date, no specific study has investigated radiation exposure during coil embolization. This study aimed to investigate the potential of lowering the pulse rate to decrease radiation exposure during coil embolization while maintaining patient safety. Radiation data and clinical features of 70 patients who underwent coil embolization between 2015 and 2020 were retrospectively analyzed. Since July 2017, the pulse rate was regulated from 7.5 to 4 frames per second (f/s). Statistical analyses were performed to examine the correlation between pulse rate and radiation exposure. Out of the 70 procedures, 30 were performed at the standard pulse rate (7.5 f/s), and 40 were performed at the lower pulse rate (4 f/s). In the lower-pulse-rate group, the absorbed dose to the patient (AK) was 2580.7 (±217) mGy, whereas in the standard-pulse-rate group, it was 4760 (±411.1). Both the dose-area product (DAP) and AK were substantially reduced in the low pulse rate group (p = 0.000002). There was a significant correlation between DAP and AK and pulse rate (p = 0.004, p = 0.0017, respectively). Moreover, there was no significant correlation between pulse rate and perioperative complications. Our findings suggest that using a lower pulse rate (4 f/s) can effectively reduce radiation exposure during coil embolization for cerebral aneurysms while ensuring patient safety.

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.

Radiation Exposure, Training, and Safety in Cardiology

Exposure to ionizing radiation is an inherent occupational health hazard in clinical cardiology. Health risks have been reported previously, including predilection to cancer. In addition, orthopedic injury due to prolonged wearing of heavy protective lead aprons, which are mandatory to reduce radiation risk, have been extensively documented. Cardiology as a specialty has grown with rising volumes of increasingly complex procedures. This includes electrophysiological, coronary, and structural intervention, advanced heart failure/transplant management, and diagnostic imaging. Both the operator as well imaging specialists are exposed to radiation, particularly in structural interventions where interventional cardiologists and structural imagers work closely. Increasingly, women interested in cardiology may deselect the field due to radiation concerns. This expert document highlights the risks of radiation exposure in cardiology, including practical tips within various subspecialty fields such as interventional/structural cardiology, electrophysiology, imaging, advanced heart failure, and pediatric cardiology.

Radiation Doses to the Entire Catheterization Laboratory Team With a Novel Radiation Protection Device

Background

A novel radiation protection system has recently been shown to shield the primary operator from scatter radiation, but whether it shields other members of the catheterization laboratory team remains unknown.

Methods

Radiation exposure data were collected prospectively in 50 coronary angiography cases, in which 25 were completed using standard radiation protection and 25 with a novel system consisting of a series of rigid shields and flexible radiation-resistant drapes. Radiation doses, measured with real-time dosimeters, were compared between the 2 groups.

Results

There were no significant differences between groups with respect to patient or procedural characteristics, including air kerma (P = .97) and dose area product (P = .17). The primary operator received a median head-level radiation dose of 0.0 [0.0, 0.0] μSv with the novel radiation protection system and 2.1 [0.7, 3.3] μSv with standard radiation protection (P < .001). Scrub technologists had a median head-level radiation dose of 0.0 [0.0, 0.0] μSv with the novel radiation protection system and 0.3 [0.1, 0.4] μSv with standard radiation protection (P < .001). The median head-level radiation dose among circulating nurses was 0.0 [0.0, 0.0] μSv with the novel radiation protection system and was 0.1 [0.0, 0.2] μSv with standard radiation protection (P < .001).

Conclusions

Compared to standard radiation protection with lead aprons, use of a novel radiation protection system during coronary angiography was associated with significantly lower head-level radiation doses among all members of the catheterization laboratory team.

Radiation Exposure Using Rampart vs Standard Lead Aprons and Shields During Invasive Cardiovascular Procedures

Background

Radiation exposure during invasive cardiovascular procedures remains an important health care issue. Lead aprons and shields (LAS) are used to decrease radiation exposure but leave large portions of the body unshielded. The Rampart IC M1128 is a portable radiation shielding system that may significantly attenuate radiation exposure.

Methods

Catheterization laboratory teams were randomized in a 1:1 fashion to perform elective invasive cardiovascular procedures utilizing either traditional LAS or the Rampart IC M1128. Radiation exposure was measured using real-time dosimetry monitoring in prespecified anatomic locations on 3 operators (position 1: first operator/fellow; position 2: second operator/attending; and position 3: catheterization laboratory nurse/technologist). Radiation exposure was measured on a per-case basis.

Results

In total, 100 consecutive cases were randomized in this study (47 Rampart; 53 LAS). There was no difference in fluoroscopy time (12.3 minutes for Rampart vs 15.4 minutes for LAS; P = .52), dose area product (288 Gy⋅cm2 for Rampart vs 376.5 Gy⋅cm2 for LAS; P = .52), or scatter radiation (38.8 mRem for Rampart vs 46.8 mRem for LAS; P = .61) between the groups. There was significantly lower total body radiation (in milliroentgen equivalent man) exposure using the Rampart than that using LAS for each team member: position 1-0.1 mRem for Rampart vs 2.2 mRem for LAS; P < .001; position 2-0.1 mRem Rampart vs 3.2 mRem LAS; P < .001; and position 3-0.0 mRem for Rampart vs 0.8 mRem for LAS; P < .001.

Conclusions

During routine clinical procedures, the Rampart system significantly decreases total body radiation exposure compared with traditional LAS.

Comprehensive Shielding System Enhances Radiation Protection for Structural Heart Procedures

Background

This study of radiation exposure (RE) to physicians performing structural heart procedures evaluated the efficacy of a novel comprehensive radiation shield compared to those of traditional shielding methods. A novel comprehensive shielding system (Protego, Image Diagnostics Inc) has been documented to provide superior RE protection during coronary procedures compared to that provided by a standard "drop down" shield. The purpose of this study was to assess the efficacy of this shield in transcatheter aortic valve replacement (TAVR) procedures, which are associated with disproportionate RE to operators.

Methods

This single-center, 2-group cohort, observational analysis compared RE to the primary physician operator performing TAVR using the Protego shield (n = 25) with that using a standard drop-down shield with personal leaded apparel (n = 25). RE was measured at both thyroid and waist levels with a real-time dosimetry system (RaySafe i3, RaySafe) and was calculated on a mean per case basis. Data were collected on additional procedural parameters, including access site(s) for device implantation, per case fluoroscopy time, air kerma, and patient factors, including body mass index. Between-group comparisons were conducted to evaluate RE by group and measurement sites.

Results

The Protego system reduced operator RE by 99% compared to that using standard protection. RE was significantly lower at both the thyroid level (0.08 ± 0.27 vs 79.2 ± 62.4 μSv; P < .001) and the waist level (0.70 ± 1.50 vs 162.0 ± 91.0 μSv, P < .001). "Zero" total RE was documented by RaySafe in 60% (n = 15) of TAVR cases using Protego. In contrast, standard protection did not achieve zero exposure in a single case.

Conclusions

The Protego shield system provides superior operator RE protection during TAVR procedures. This shield allows operators to work without the need for personal lead aprons and has potential to reduce catheterization laboratory occupational health hazards.

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.

The Radiobiological Characterization of Human and Porcine Lens Cells Suggests the Importance of the ATM Kinase in Radiation-Induced Cataractogenesis

Studies about radiation-induced human cataractogenesis are generally limited by (1) the poor number of epithelial lens cell lines available (likely because of the difficulties of cell sampling and amplification) and (2) the lack of reliable biomarkers of the radiation-induced aging process. We have developed a mechanistic model of the individual response to radiation based on the nucleoshuttling of the ATM protein (RIANS). Recently, in the frame of the RIANS model, we have shown that, to respond to permanent endo- and exogenous stress, the ATM protein progressively agglutinates around the nucleus attracted by overexpressed perinuclear ATM-substrate protein. As a result, perinuclear ATM crowns appear to be an interesting biomarker of aging. The radiobiological characterization of the two human epithelial lens cell lines available and the four porcine epithelial lens cell lines that we have established showed delayed RIANS. The BFSP2 protein, found specifically overexpressed around the lens cell nucleus and interacting with ATM, may be a specific ATM-substrate protein facilitating the formation of perinuclear ATM crowns in lens cells. The perinuclear ATM crowns were observed inasmuch as the number of culture passages is high. Interestingly, 2 Gy X-rays lead to the transient disappearance of the perinuclear ATM crowns. Altogether, our findings suggest a strong influence of the ATM protein in radiation-induced cataractogenesis.

The Long-Term Impact of Ionizing Radiation on DNA Damage in Patients Undergoing Multiple Cardiac Catheterizations

Ionizing radiation (IR) exposures have increased exponentially in recent years due to the rise in diagnostic and therapeutic interventions. A number of small-scale studies investigated the long-term effect of IR on health workers or immediate effects of IR on patients undergoing catheterization procedures; however, the long-term impact of multiple cardiac catheterizations on DNA damage on a patient population is not known. In this study, the effects of IR on DNA damage, based on micronuclei (MN) frequency and 8-hydroxy-2'-deoxyguanosine (8-OHdG) as markers in peripheral lymphocytes, were evaluated in patients who previously underwent multiple cardiac catheterization procedures. Moreover, genetic polymorphisms in genes PARP1 Val762Ala, OGG1 Ser326Cys, and APE1 Asn148Glu as a measure of sensitivity to radiation exposure were also investigated in the same patient population. The patients who underwent ≥ 3 cardiac catheterization procedures revealed higher DNA injury in comparison to the patients who underwent ≤ 2 procedures, documented with the presence of higher level of MN frequency (6.4 ± 4.8 vs. 9.1 ± 4.3, p = 0.002) and elevated serum 8-OHdG levels (33.7 ± 3.8 ng/mL vs. 17.4 ± 1.9 ng/mL, p = 0.001). Besides, OGG1 Ser326Cys and APE1 Asn148Glu heterozygous and homozygous polymorphic types, which are related with DNA repair mechanisms, were significantly associated with MN frequency levels (p = 0.006 for heterozygous and p = 0.001 for homozygous with respect to OGG1 Ser326Cys, p = 0.007 for heterozygous and p = 0.001 for homozygous with respect to APE1 Asn148Glu). There was no significant difference in terms of PARP1 Val762Ala gene polymorphism between two groups.

Practical guidance to reduce radiation exposure in electrophysiology applying ultra low-dose protocols: a European Heart Rhythm Association review

Interventional electrophysiology offers a great variety of treatment options to patients suffering from symptomatic cardiac arrhythmia. Catheter ablation of supraventricular and ventricular tachycardia has globally evolved a cornerstone in modern arrhythmia management. Complex interventional electrophysiological procedures engaging multiple ablation tools have been developed over the past decades. Fluoroscopy enabled interventional electrophysiologist throughout the years to gain profound knowledge on intracardiac anatomy and catheter movement inside the cardiac cavities and hence develop specific ablation approaches. However, the application of X-ray technologies imposes serious health risks to patients and operators. To reduce the use of fluoroscopy during interventional electrophysiological procedures to the possibly lowest degree and to establish an optimal protection of patients and operators in cases of fluoroscopy is the main goal of modern radiation management. The present manuscript gives an overview of possible strategies of fluoroscopy reduction and specific radiation protection strategies.

Lead Cap Use in Interventional Cardiology: Time to Protect Our Head in the Cardiac Catheterisation Laboratory?

Background: Radiation exposure is an occupational hazard for interventional cardiologists and cardiac catheterisation laboratory staff that can manifest with serious long-term health consequences. Personal protective equipment, including lead jackets and glasses, is common, but the use of radiation protective lead caps is inconsistent. Methods: A systematic review qualitative assessment of five observational studies using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines protocol was performed. Results: It was concluded that lead caps significantly reduce radiation exposure to the head, even when a ceiling-mounted lead shield was present. Conclusion: Although newer protective systems are being studied and introduced, tools, such as lead caps, need to be strongly considered and employed in the catheterisation laboratory as mainstay personal protective equipment.

Occupational radiation exposure of neurointerventionalists during endovascular stroke treatment

BACKGROUND

Radiological neuro-interventions, especially endovascular stroke treatment (EST), are increasing in case numbers worldwide with increasing occupational radiation exposure. Aim of this study was to define the radiation exposure of neurointerventionalists (NI) during EST and to compare the accumulated dose reaching the left arm with the left temple.

METHODS

This is a prospective observational study in a tertiary stroke center conducted between 11/2021 and 07/2022. Radiation exposure was measured using real time dosimetry with dosimeters being carried by the NI during EST simultaneously at the left temple and left arm. The effective dose [µSV] per dose area product (DAP) and potential influencing factors were compared in univariate analysis between the two dosimeter positions.

RESULTS

In total, 82 ESTs were analyzed with a median DAP of 6179 µGy*m² (IQR 3271 µGy*m²-11720 µGy*m²). The accumulated dose at the left arm and left temple correlated with the DAP and fluoroscopy time of the EST (DAP and arm: p = 0.01, DAP and temple: p = 0.006). The radiation exposure (RE) showed a wide range and did not differ between the two dosimeter positions (median, IQR arm 7 µSV, IQR 3.1-16.9 µSV, min. 0.3 µSV max. 64.5 µSV) vs. head 7 µSv, IQR 3.2-17.4 µSV, min. 0.38 µSV, max. 48.6 µSV, p = 0.94). Occupational RE depends on the number of thrombectomy attempts, but not the target vessel occlusion location or the NI's body height.

CONCLUSION

Neurointerventionalists experience a generally low but very variable radiation exposure during EST, which depends on the intervention's fluoroscopy time and dose area product as well as thrombectomy attempts but does not differ between left temple and left arm.

Comprehensive Radiation Shield Minimizes Operator Radiation Exposure and Obviates Need for Lead Aprons

Background

The catheterization laboratory predisposes to occupational health hazards. Chronic radiation exposure (RE) direct injuries include a predilection to cataracts and concerns for cancers. Indirectly adverse effects underly the prevalence of orthopedic maladies in interventionists, linked to the burden of mandatory protective lead aprons. A novel comprehensive shielding system (Protego, Image Diagnostics Inc) has been validated in early studies to provide excellent radiation protection. The system is designed to reduce operator RE sufficient to eliminate the need for personal lead aprons. Recent system refinements offer potentially even greater degrees of protection. This clinical study evaluated the efficacy of this system.

Methods

This single-center 2-group cohort study compared physician operator RE utilizing the latest iteration of the Protego shield (n = 25 cases) or standard protection (personal leaded apparel and drop-down shield, n = 25 cases) during routine cardiac catheterization procedures. RE at both thyroid and waist levels were measured with a real-time dosimetry system (Raysafe) and calculated on a mean per case basis at both thyroid and waist levels. Additional parameters collected included procedure type, access site, per case fluoroscopy time, and patient factors including body mass index. Between-group comparisons were conducted to evaluate RE by group and measurement sites.

Results

Protection with Protego was superior to standard methods. Protego showed markedly lower RE at both the thyroid level (0.36 ± 0.86 vs 58.5 ± 50.2 μSv; P < .001) and the waist level (0.84 ± 2.99 vs 121.4 ± 171.2 μSv; P < .001. "Zero" total RE was documented in 68% (n = 17) of Protego cases; in contrast, standard protection did not achieve "zero" exposure in a single case.

Conclusions

The Protego shield system provides excellent RE protection to the physician operator, achieving "zero" RE in two-thirds of cases. RE was superior to standard protection methods. The magnitude of protection achieves state regulatory standards sufficient to allow operators to perform procedures without orthopedically burdensome lead aprons. This shield system has the potential to reduce occupational health hazards.

Robotically-assisted neuro-endovascular procedures: Single-Center Experience and a Review of the Literature

INTRODUCTION

Robotics could expand treatment of rapidly progressive pathologies such as acute ischemic stroke, with the potential to provide populations in need prompt access to neuro-endovascular procedures.

METHODS

Robotically-assisted (RA) neuro-endovascular procedures (RANPs) performed at our institution were retrospectively examined (RA-group, RG). A control group of manual neuro-endovascular procedures was selected (manual group, MG). Total operating room (OR) time, procedural time, contrast media use, fluoroscopy time, conversion from RA to manual control, procedural success, and complication rates were compared. A learning curve was identified.

RESULTS

Forty-one (41) RANPs were analyzed. Ages ranged from 20-82 y.o. Indications included diagnostic cerebral angiography (37), extracranial carotid artery stenting (3), and transverse sinus stent (1). Total OR time was longer in RG (median 86 vs. 71 min, p < 0.01). Procedural time (median 56 vs. 45 min, p = 0.12), fluoroscopy time (median 12 vs. 12 min, p = 0.69) and contrast media usage (82 vs. 92 ml, p = 0.54) were not significantly different. Patient radiation exposure was similar, considering similar fluoroscopy times. Radiation exposure and lead apron use were virtually absent for the main surgeon in RG. Procedural success was 83% and conversion from RA to manual control was 17% in RG. No treatment-related complications occurred. A learning curve showed that, after the fifth procedure, procedural times reduced and stabilized.

CONCLUSIONS

This series may contribute to further demonstrating the safety and feasibility of RANPs. RANPs can potentially reduce radiation exposure and physical burden for health personnel, expand acute cerebrovascular treatment to underserved areas, and enhance telementoring. Prospective studies are necessary for results to be generalized.

A novel comprehensive radiation shielding system eliminates need for personal lead aprons in the catheterization laboratory

OBJECTIVES

This clinical study evaluated the efficacy of a novel radiation shielding system for the cardiac catheterization laboratory designed to provide comprehensive protection that obviates the need for personal lead aprons.

BACKGROUND

Invasive Cardiologists are exposed to occupational health hazards related directly to radiation exposure (RE) and indirectly to the orthopedic burden of wearing only partially protective lead aprons. Innovations to reduce these risks are warranted. A novel comprehensive shielding system (Protego^TM , Image Diagnostics Inc, Fitchburg, Ma) has been validated in pre-clinical studies to provide excellent radiation protection, sufficient for the State of Michigan to certify it for use without need for personal lead aprons.

METHODS

This clinical analysis measured RE to a single Physician operator utilizing the Protego^TM shield (and not wearing personal lead apron) during routine cardiac catheterization procedures (diagnostic and interventional). RE was measured at both thyroid and waist level with a real-time dosimetry system (Raysafe^TM , Billdal, Sweden), calculated on a median per case basis (mrems). Additional parameters collected included procedure type, access site, per case fluoroscopy time, and patient factors including body mass index.

RESULTS

In n=98 cases (25% diagnostic, 75% interventional including 22% chronic total occlusions), median/case RE was 0.4 mrems (thyroid) and 0.2 mrems (waist). RE=0 in 12 cases. In no case did radiation exposure exceed 3.2 mrems.

CONCLUSION

The Protego^TM shield system provides excellent RE protection to the Physician operator, without the need for personal lead aprons and has the potential to reduce catheterization laboratory occupational health hazards.

Discrete soft actor-critic with auto-encoder on vascular robotic system

Instrument delivery is critical part in vascular intervention surgery. Due to the soft-body structure of instruments, the relationship between manipulation commands and instrument motion is non-linear, making instrument delivery challenging and time-consuming. Reinforcement learning has the potential to learn manipulation skills and automate instrument delivery with enhanced success rates and reduced workload of physicians. However, due to the sample inefficiency when using high-dimensional images, existing reinforcement learning algorithms are limited on realistic vascular robotic systems. To alleviate this problem, this paper proposes discrete soft actor-critic with auto-encoder (DSAC-AE) that augments SAC-discrete with an auxiliary reconstruction task. The algorithm is applied with distributed sample collection and parameter update in a robot-assisted preclinical environment. Experimental results indicate that guidewire delivery can be automatically implemented after 50k sampling steps in less than 15 h, demonstrating the proposed algorithm has the great potential to learn manipulation skill for vascular robotic systems.

Physician Radiation Exposure During Endomyocardial Biopsy and Right Heart Catheterization

BACKGROUND

Cardiologists performing coronary angiography (CA) and percutaneous coronary intervention (PCI) are at risk of health problems related to chronic occupational radiation exposure. Unlike during CA and PCI, physician radiation exposure during right heart catheterization (RHC) and endomyocardial biopsy (EMB) has not been adequately studied. The objective of this study was to assess physicians' radiation doses during RHC with and without EMB and compare them to those of CA and PCI.

METHODS

Procedural head-level physician radiation doses were collected by real-time dosimeters. Radiation-dose metrics (fluoroscopy time, air kerma [AK] and dose area product [DAP]), and physician-level radiation doses were compared among RHC, RHC with EMB, CA, and PCI.

RESULTS

Included in the study were 351 cardiac catheterization procedures. Of these, 36 (10.3%) were RHC, 42 (12%) RHC with EMB, 156 (44.4%) CA, and 117 (33.3%) PCI. RHC with EMB and CA had similar fluoroscopy time. AK and DAP were progressively higher for RHC, RHC with EMB, CA, and PCI. Head-level physician radiation doses were similar for RHC with EMB vs CA (P = 0.07). When physicians' radiation doses were normalized to DAP, RHC and RHC with EMB had the highest doses.

CONCLUSION

Physicians' head-level radiation doses during RHC with EMB were similar to those of CA. After normalizing to DAP, RHC and RHC with EMB were associated with significantly higher physician radiation doses than CA or PCI. These observations suggest that additional protective measures should be undertaken to decrease physicians' radiation exposure during RHC and, in particular, RHC with EMB.

Interventional cardiology and X-ray exposure of the head: overview of clinical evidence and practical implications

Interventional cardiologists are significantly exposed to X- rays and no dose of radiation may be considered well tolerated or harmless. Leaded aprons protect the trunk and the thyroid gland, leaded glasses protect the eyes. The operator's legs, arms, neck and head are, instead, not fully protected. In fact, the operator's brain remains the closest part to the primary X-ray beam and scatter in most interventional procedures and specifically the physician's front head is the most exposed region during device implantation performed at the patient's side. After the initial description of cases of brain and neck tumours, additional reports on head and neck malignancies have been published. Although a direct link between operator radiation exposure and brain cancer has not been established, these reports have heightened awareness of a potential association. The use of lead-based cranial dedicated shields may help reduce operator exposure but upward scattered radiation, weight and poor tolerability have raised concerns and hindered widespread acceptance. The purpose of this review is to describe current knowledge on occupational X-ray exposure of interventional cardiologists, with a special focus on the potential risks for the head and neck and efficacy of available protection devices.

Robotically performed diagnostic coronary angiography

OBJECTIVE

This study was performed to investigate the efficacy and safety of robotic diagnostic coronary angiography.

BACKGROUND

Robotic percutaneous coronary intervention is associated with marked reductions in physician radiation exposure. Development of robotic diagnostic coronary angiography might similarly impact occupational safety.

METHODS

Stable patients referred for coronary angiography were prospectively enrolled. After obtaining vascular access, diagnostic catheters were manually advanced over a wire to the ascending aorta. All subsequent catheter movements were performed robotically. The primary endpoint was procedural success, defined as robotic completion of coronary angiography without conversion to a manual procedure and the absence of procedural major adverse cardiovascular events (MACE-cardiac death, cardiac arrest, or stroke) and major angiographic complications (coronary/aortic dissection or embolization). The primary hypothesis was that the observed rate of the primary endpoint, evaluated at the completion of coronary angiography, would meet a pre-specified performance goal of 74.5%.

RESULTS

Among 46 consecutive patients (age 67 ± 12 years; 69.6% male), diagnostic coronary angiography was completed robotically in all cases without the need for manual conversion and without any MACE or major angiographic complications. Thus, procedural success was 100%, which was significantly higher than the pre-specified performance goal (p < 0.001). Robotic coronary angiography was completed using 2 [2, 3] catheters per case with a median procedural time of 15 [11, 20] minutes.

CONCLUSIONS

Robotic diagnostic coronary angiography was performed with 100% procedural success and no observed complications. These results support the performance of future studies to further explore robotic coronary angiography.

Safety and effectiveness of introducing a robotic-assisted percutaneous coronary intervention program in a tertiary center: a prospective study

BACKGROUND

Robotic-assisted percutaneous coronary intervention (PCI) is a novel technology that permits remote operation of interventional devices. However, little is known about the safety and effectiveness of introducing a robotic PCI program in a hospital already experienced in traditional coronary angioplasty.

METHODS

Prospective single-arm survey to assess the safety and effectiveness of robotic-assisted PCI in comparison to pre-defined performance goals. The study cohort comprised all consecutive cases treated with robotic PCI since its introduction. The safety primary endpoint was a composite of (I) overall death or (II) non-fatal adverse events related to target vessel complications (stent thrombosis, myocardial infarction, vessel perforation or cardiac tamponade, or repeat invasive treatment) during the index hospitalization. The efficacy primary endpoint was robotic-assisted procedural success, a composite of (I) successful dilatation of the target lesion and (II) successful robotic assistance, defined as absent non-planned manual conversion.

RESULTS

A total of 83 patients and 112 lesions were prospectively enrolled. The rate of angiographic success was 99.1%. From these, 97 lesions (86.6%) were treated with only robotic PCI or with hybrid according to the pre-interventional plan. The rates of efficacy and safety primary endpoints were 85.7% and 2.4% respectively (P<0.01 for non-inferior to the pre-defined performance threshold).

CONCLUSIONS

Introduction of robotic-assisted PCI in a tertiary center was associated with safe and effective results, comparable to pre-defined goals of optimal performance.

Radiation protection for the interventional cardiologist: Practical approach and innovations

Use of ionizing radiation during cardiac catheterization interventions adversely impacts both the patients and medical staff. In recent years, radiation dose in cardiac catheterization interventions has become a topic of increasing interest in interventional cardiology and there is a strong interest in reducing radiation exposure during the procedures. This review presents the current status of radiation protection in the cardiac catheterization laboratory and summarizes a practical approach for radiation dose management for minimizing radiation exposure. This review also presents recent innovations that have clinical potential for reducing radiation during cardiac interventions.

The use of digital magnification to reduce radiation dose in the cardiac catheter laboratory

OBJECTIVES

To audit whether using magnification of images by use of a large viewing screen using digital matrix magnification which enlarges the image by 33% without using the X-ray machine zoom magnification protocols on a Siemens Artis Zee X-ray machine in a cardiac catheter laboratory results in a reduction of kerma-area product (KAP) for both diagnostic and interventional procedures. This reduction was predicted in an in vitro study in our laboratory, which has previously shown a 20.4% reduction in KAP.

METHODS

A retrospective analysis was conducted of the radiation exposure to compare the measured KAP recorded during the period when conventional magnification with automatic brightness and dose control was used on a Siemens Artis Zee X-ray machine with a flat panel detector and when magnification settings were avoided by using a large screen to enlarge and project a non-magnified image by digital magnification. The analysis was carried out for patients having a diagnostic coronary angiogram and those having an interventional coronary procedure.

RESULTS

For diagnostic coronary angiograms the median KAP per procedure in the period using conventional magnification was 2124.5 µGy.m² compared to 1401 µGy.m² when image matrix magnification was used, a 34% reduction (p < 0.0001). For interventional coronary procedures, the median KAP per procedure in the period using conventional magnification was 3791 µGy.m² compared to 2568.5 µGy.m² when image matrix magnification was used, a 32% reduction (p < 0.0001).

CONCLUSION

Avoiding using conventional magnification in the cardiac catheter laboratory and using a large screen to magnify images was associated with a statistically significant greater than 30% reduction in KAP.

ADVANCES IN KNOWLEDGE

This paper is the proof in clinical practice of a theoretical conclusion that radiation dose (KAP) is reduced by use of Image matrix magnification using a large viewing screen without the need to use X-ray tube magnification without significant loss of image resolution in interventional cardiology. The same approach will be useful in interventional radiology.

Body pain - An unheeded personal health hazard in interventional cardiologists: A national online cross-sectional survey study in China

INTRODUCTION

Interventional cardiology procedures (ICPs) have become the mainstay treatments in cardiology diseases and increased rapidly. This study aims to assess the occupational health hazards (OHHs) related to the long-time wearing of lead personal protective equipment and reveal health protection needs in interventional cardiologists.

METHODS AND RESULTS

We invited interventional and non-interventional cardiologists in tertiary hospitals in China to participate in an online cross-sectional survey on their health status, utilization of personal protective equipment (PPE), and personal health protection (PHP) needs. Propensity score methods were used for comparisons of OHHs between the matched interventional and non-interventional cardiologists. Totally, 642 interventional and 402 non-interventional cardiologists completed the survey. The interventional cardiologists had significantly higher incidence of body pain (56.6% vs. 24.2%, p < 0.001), bone and joint disease (21.7% vs. 8.6%, p = 0.001), cataract (3.5% vs. 0%, p = 0.039), and anxiety (8.1% vs. 2.5%, p = 0.029) than the matched non-interventional cardiologists. The risk of back pain was independently associated with female gender, performing percutaneous coronary intervention procedure or ≥ 2 types of ICP, and the personal annual volume of ICPs. Only 3.3% of interventional cardiologists were satisfied with PPE and 83.0% of them complained of physical toll caused by heavy PPE. 90.7% were willing to conduct ICP without radiation exposure.

CONCLUSIONS

Body pain was the main OHH in interventional cardiologists likely due to wearing heavy lead PPE for long working hours. Besides training more interventional cardiologists, the adoption of emerging technologies without heavy lead PPE will be a promising way to reduce the OHH burden.

Suspended lead suit and physician radiation doses during coronary angiography

OBJECTIVE

This study was performed to evaluate physician radiation doses with the use of a suspended lead suit.

BACKGROUND

Interventional cardiologists face substantial occupational risks from chronic radiation exposure and wearing heavy lead aprons.

METHODS

Head-level physician radiation doses, collected using real-time dosimeters during consecutive coronary angiography procedures, were compared with the use of a suspended lead suit versus conventional lead aprons. Multiple linear regression analyses were completed using physician radiation doses as the response and testing patient variables (body mass index, age, sex), procedural variables (right heart catheterization, fractional flow reserve, percutaneous coronary intervention, radial access), and shielding variables (radiation-absorbing pad, accessory lead shield, suspended lead suit) as the predictors.

RESULTS

Among 1054 coronary angiography procedures, 691 (65.6%) were performed with a suspended lead suit and 363 (34.4%) with lead aprons. There was no significant difference in dose area product between groups (61.7 [41.0, 94.9] mGy·cm² vs. 64.6 [42.9, 96.9] mGy·cm² , p = 0.20). Median head-level physician radiation doses were 10.2 [3.2, 35.5] μSv with lead aprons and 0.2 [0.1, 0.9] μSv with a suspended lead suit (p < 0.001), representing a 98.0% reduced dose with suspended lead. In the fully adjusted regression model, the use of a suspended lead suit was independently associated with a 93.8% reduction (95% confidence interval: -95.0, -92.3; p < 0.001) in physician radiation dose.

CONCLUSION

Compared to conventional lead aprons, the use of a suspended lead suit during coronary angiography was associated with marked reductions in head-level physician radiation doses.

BRAIN AND EYE AS POTENTIAL TARGETS FOR IONIZING RADIATION IMPACT: PART II - RADIATION CEREBRO/OPHTALMIC EFFECTS IN CHILDREN, PERSONS EXPOSED IN UTERO, ASTRONAUTS AND INTERVENTIONAL RADIOLOGISTS

BACKGROUND

Ionizing radiation (IR) can affect the brain and the visual organ even at low doses, while provoking cognitive, emotional, behavioral, and visual disorders. We proposed to consider the brain and the visual organ as potential targets for the influence of IR with the definition of cerebro-ophthalmic relationships as the «eye-brain axis».

OBJECTIVE

The present work is a narrative review of current experimental, epidemiological and clinical data on radiation cerebro-ophthalmic effects in children, individuals exposed in utero, astronauts and interventional radiologists.

MATERIALS AND METHODS

The review was performed according to PRISMA guidelines by searching the abstract and scientometric databases PubMed/MEDLINE, Scopus, Web of Science, Embase, PsycINFO, Google Scholar, published from 1998 to 2021, as well as the results of manual search of peer-reviewed publications.

RESULTS

Epidemiological data on the effects of low doses of IR on neurodevelopment are quite contradictory, while data on clinical, neuropsychological and neurophysiological on cognitive and cerebral disorders, especially in the left, dominant hemisphere of the brain, are nore consistent. Cataracts (congenital - after in utero irradiation) and retinal angiopathy are more common in prenatally-exposed people and children. Astronauts, who carry out longterm space missions outside the protection of the Earth's magnetosphere, will be exposed to galactic cosmic radiation (heavy ions, protons), which leads to cerebro-ophthalmic disorders, primarily cognitive and behavioral disorders and cataracts. Interventional radiologists are a special risk group for cerebro-ophthalmic pathology - cognitivedeficits, mainly due to dysfunction of the dominant and more radiosensitive left hemisphere of the brain, andcataracts, as well as early atherosclerosis and accelerated aging.

CONCLUSIONS

Results of current studies indicate the high radiosensitivity of the brain and eye in different contingents of irradiated persons. Further research is needed to clarify the nature of cerebro-ophthalmic disorders in different exposure scenarios, to determine the molecular biological mechanisms of these disorders, reliable dosimetric support and taking into account the influence of non-radiation risk factors.

Effectiveness of a Real-Time X-ray Dosimetry Monitor in Reducing Radiation Exposure in Coronary Procedures: The ESPRESSO-Raysafe Randomized Trial

Background—Several methods to reduce radiation exposure in the setting of coronary procedures are available on the market, and we previously showed that additional radiation shields reduce operator exposure during radial interventions. We set out to examine the efficacy of real-time personal dosimetry monitoring in a real-world setting of radial artery catheterization. Methods and Results—In an all-comer prospective, parallel study, consecutive coronary diagnostic and intervention procedures were performed with the use of standard radiation shield alone (control group) or with the addition of a real-time dosimetry monitoring system (Raysafe, Billdal, Sweden, monitoring group). The primary outcome was the difference in exposure of the primary operator among groups. Additional endpoints included patient, nurse, second operator exposure and fluoroscopy time. A total of 700 procedures were included in the analysis (n = 369 in the monitoring group). There were no differences among groups in patients’ body mass index (p = 0.232), type of procedure (intervention vs. diagnostic, p = 0.172), and patient sex (p = 0.784). Fluoroscopy time was shorter in the monitoring group (5.6 (5.1–6.2) min vs. 7.0 (6.1–7.7) min, p = 0.023). Radiation exposure was significantly lower in the monitoring group for the patient (135 (115–151) µSv vs. 208 (176–245) µSv, p < 0.0001) but not for the first operator (9 (7–11) µSv vs. 10 (8–11), p = 0.70) and the assistant (2 (1–2) µSv vs. 2 (1–2) µSv, p = 0.121). Conclusions—In clinical daily practice, the use of a real-time dosimetry monitoring device reduces patient radiation exposure and fluoroscopy time without an effect on operator radiation exposure.

Comparison of a contrast-to-noise ratio-driven exposure control and a regular detector dose-driven exposure control in abdominal imaging in a clinical angiography system

PURPOSE

The first purpose of this phantom study was to verify whether a contrast-to-noise ratio (CNR)-driven exposure control (CEC) can maintain target CNR in angiography more precisely compared to a conventional detector dose-driven exposure control (DEC). The second purpose was to estimate the difference between incident air kerma produced by CEC and DEC when both exposure controls reach the same CNR.

METHODS

A standardized 3D-printed phantom with an iron foil and a cavity, filled with iodinated contrast material, was developed to measure CNR using different image acquisition settings. This phantom was placed into a stack of polymethylmethacrylate and aluminum plates, simulating a patient equivalent thickness (PET) of 2.5-40 cm. Images were acquired using fluoroscopy and digital radiography modes with CEC using one image quality level and four image quality gradients and DEC having three different detector dose levels. The spatial frequency weighted CNR and incident air kerma were determined. The differences in incident air kerma between DEC and CEC were estimated.

RESULTS

When using DEC, CNR decreased continuously with increasing attenuation, while CEC within physical limits maintained a predefined CNR level. Furthermore, CEC could be parameterized to deliver the CNR as a predefined function of PET. To provide a given CNR level, CEC used equal or lower air kerma than DEC. The mean estimated incident air kerma of CEC compared to DEC was between 3% (PET 20 cm) and 40% (PET 27.5 cm) lower in fluoroscopy and between 1% (PET 20 cm) and 55% (PET 2.5 cm) lower in digital radiography while maintaining CNR.

CONCLUSION

Within physical and legislative limits, the CEC allows for a flexible adjustment of the CNR as a function of PET. Thus, the CEC enables task-dependent examination protocols with predefined image quality in order to easier achieve the as low as reasonably achievable principle. CEC required equal or lower incident air kerma than DEC to provide similar CNR, which allows for a substantial reduction of skin radiation dose in these situations.

An assessment of radiation use, knowledge and concerns in trainee cardiologists in Ireland

OBJECTIVE

To evaluate knowledge, routine use and concerns of trainee cardiologists in the Republic of Ireland regarding radiation use in the cardiac catheterization laboratory.

METHODS

We handed out a Radiation Questionnaire to cardiology trainees in February 2020 at the Irish Cardiac Society "Spring Meeting". The questionnaire assessed radiation protection use amongst trainees and tested knowledge of X-ray basics.

RESULTS

Many trainees report inadequate access to properly sized lead protection, and infrequent dosimeter usage. Over one-third of trainees report musculoskeletal issues from wearing leads, the majority of whom use correct size lead <60% of the time.33.3% report radiation concerns will affect their decision making regarding subspeciality training, but notably 83.3% of females and only 19% of males surveyed report this, showing this is a bigger issue for females in cardiology. Less than half of trainees feel adequately educated about radiation.

CONCLUSION

Our assessment show deficiencies in the provision and use of personal protective equipment to trainees, highlights extra radiation concerns of female cardiology trainees, and notes gaps in knowledge in radiation use.

ADVANCES IN KNOWLEDGE

Our assessment highlights deficiencies in the education of cardiology trainees regarding ionizing radiation, and suggests this area needs to be improved upon.

Level of Supervision and Radiation Exposure of Senior Orthopedic Residents During Surgical Treatment of Proximal Femur Fracture

The sustained use of intraoperative fluoroscopy has led to increased use of minimally invasive surgical techniques, enhanced surgeon proficiency, improved anatomic corrections, reduced patient morbidity, earlier functional recovery, and decreased length of hospital stay. As a result, orthopedic attending surgeons and residents are exposed to more radiation, increasing the risk of cancer and radiation-induced cataracts compared with the general population and those who work in other surgical specialties. The magnitude of radiation exposure depends on the susceptibility of the tissues affected, medical specialty, the position of the C-arm, distance from the radiation beam, level of difficulty of the surgical procedure, surgeon experience, level of resident training, and level of supervision by the attending surgeon. However, little information is available on the effect of supervision level on radiation exposure for orthopedic senior residents. The goal of this study was to investigate whether level of supervision by the attending surgeon affects the radiation exposure of orthopedic senior residents during surgical treatment of proximal femur fracture with cephalomedullary nail fixation. This retrospective cohort study was performed from January 2019 to March 2019. No significant relationship between supervision level and radiation exposure of senior residents was observed. Supervision level does not significantly affect radiation exposure for senior residents; therefore, the implementation of standardized training in radiation safety may be a more essential measure to decrease radiation exposure. [Orthopedics. 2021;44(3):e402-e406.].

A novel catheterization laboratory radiation shielding system: Results of pre-clinical testing

BACKGROUND

This pre-clinical study evaluated the efficacy of a novel shielding system to reduce scatter radiation in the cardiac catheterization laboratory.

METHODS

Using a scatter radiation phantom in a standard cardiac catheterization laboratory, a radiation physicist recorded radiation measurements at 20 reference points on the operator side of the table. Measurements were made with fluoroscopy and cine with the C-arm in the posterior-anterior (PA) and 40 degrees left anterior oblique (LAO) orientations. Scatter radiation doses were compared with and without use of the shielding system.

RESULTS

Use of the shielding system was associated with >94.2% reduction in scatter radiation across all reference points in the PA and LAO projections with fluoroscopy and cine. With the shielding system, dose reductions at the location of the primary operator ranged from 97.8% to 99.8%. At locations of maximum scatter radiation, use of the shielding system resulted in dose reductions ranging from 97.8% to 99.8% with fluoroscopy and from 97.9% to 99.8% with cine.

CONCLUSIONS

In this pre-clinical study, a novel radiation shielding system was observed to dramatically reduce scatter radiation doses. Based on these results, clinical testing is warranted to determine whether the shielding system will enable operators and staff to perform interventional procedures with less radiation exposure that may obviate the need to wear standard lead apparel.

INDEXING WORDS

Radiation safety; occupational health; occupational hazard.

The Importance of Radiation Protection Education and Training for Medical Professionals of All Specialties

The article is part of the series of articles on radiation protection. You can find further articles in the special section of the CVIR issue. Lately, more advanced techniques have been introduced in medical imaging expanding the diagnostic and therapeutic applications of ionizing radiation. Among the various strategies that have been proposed for the management of radiation exposure, education and training seem to have a strong impact on radiation protection and dose reduction. However, according to several studies, medical professionals appear to lack knowledge on basic radiation protection aspects. Therefore, the establishment of an accreditation and certification system in radiation protection for all medical professionals employing ionizing radiation is considered as high priority. The purpose of this review article is to highlight the importance of education and training in radiation protection, provide recommendations for an effective educational program and propose an educational program structure for the different medical specialties.

The radioprotective effect of the Cathpax® AIR cabin during interventional cardiology procedures

BACKGROUND

The use of ionizing radiation during cardiac catheterization interventions adversely impacts the medical staff. Traditional radiation protection equipment is only partially effective. The Cathpax® radiation protection cabin (RPC) has proven to significantly reduce radiation exposure in electrophysiological and neuroradiology interventions. Our objective was to analyze whether the Cathpax® RPC reduces radiation dose in coronary and cardiac structural interventions in unselected real-world procedures.

METHODS AND RESULTS

In this nonrandomized all-comers prospective study, 119 consecutive cardiac interventional procedures were alternatively divided into two groups: the RPC group (n = 59) and the non-RPC group (n = 60). No significant changes in the characteristics of patients and procedures, average contrast volume, air kerma (AK), dose area-product (DAP) and fluoroscopy time between both groups were apparent. In the RPC group, the first-operator relative radiation exposure was reduced by 78% at the chest and by 70% at the wrist. This effect was consistent during different types of procedures including complex percutaneous interventions and structural procedures.

CONCLUSIONS

Our study demonstrates, for the first time, that the Cathpax® cabin significantly and efficiently reduces relative operator radiation exposure during different types of interventional procedures, confirming its feasibility in a real-world setting.

Impact of a contrast-to-noise ratio driven and material specific exposure control on image quality and radiation exposure in angiography

Conventional detector-dose driven exposure controls (DEC) do not consider the contrasting material of interest in angiography. Considering the latter when choosing the acquisition parameters should allow for optimization of x-ray quality and consecutively lead to a substantial reduction of radiation exposure. Therefore, the impact of a material-specific, contrast-to-noise ratio (CNR) driven exposure control (CEC) compared to DEC on radiation exposure was investigated. A 3D-printed phantom containing iron, tantalum, and platinum foils and cavities, filled with iodine, barium, and gas (carbon dioxide), was developed to measure the CNR. This phantom was placed within a stack of polymethylmethacrylate and aluminum plates simulating a patient equivalent thickness (PET) of 2.5-40 cm. Fluoroscopy and digital radiography (DR) were conducted applying either CEC or three, regular DEC protocols with parameter settings used in abdominal interventions. CEC protocols where chosen to achieve material-specific CNR values similar to those of DEC. Incident air kerma at the reference point(K_a,r), using either CEC or DEC, was assessed and possible K_a,r reduction for similar CNR was estimated. We show that CEC provided similar CNR as DEC at the same or lower K_a,r. When imaging barium, iron, and iodine K_a,r was substantially reduced below a PET of 20 cm and between 25 cm and 30 cm for fluoroscopy and Dr When imaging platinum and tantalum using fluoroscopy and DR and gas using DR, the K_a,r reduction was substantially higher. We estimate the K_a,r reduction for these materials between 15% and 84% for fluoroscopy and DR between 15% and 93% depending on the PET. The results of this study demonstrate a high potential for skin dose reduction in abdominal radiology when using a material-specific CEC compared to DEC. This effect is substantial in imaging materials with higher energy K-edges, which is beneficial, for example, in long-lasting embolization procedures with tantalum-based embolization material in young patients with arterio-venous malformations.

Multiple Cutaneous Cancers in an Interventional Cardiologist: Predominance in Unprotected Skin Nearest the Radiation Source

A 70 year-old interventional cardiologist, who worked in the cardiac catheterization laboratory for >35 years, developed multiple skin cancers in regions not conventionally covered by protective lead apparel. The majority of lesions were left-sided, representing cutaneous regions in closest proximity to the radiation source. Although skin not covered by lead apparel often receives frequent sun exposure, a known risk factor for skin cancer, malignancies resulting exclusively from sun exposure would not in most cases be expected to have a left-sided predominance. Additional research is warranted to study the potential link between occupational radiation exposure and skin cancer risk.

Radiation-induced lens opacities: Epidemiological, clinical and experimental evidence, methodological issues, research gaps and strategy

In 2011, the International Commission on Radiological Protection (ICRP) recommended reducing the occupational equivalent dose limit for the lens of the eye from 150 mSv/year to 20 mSv/year, averaged over five years, with no single year exceeding 50 mSv. With this recommendation, several important assumptions were made, such as lack of dose rate effect, classification of cataracts as a tissue reaction with a dose threshold at 0.5 Gy, and progression of minor opacities into vision-impairing cataracts. However, although new dose thresholds and occupational dose limits have been set for radiation-induced cataract, ICRP clearly states that the recommendations are chiefly based on epidemiological evidence because there are a very small number of studies that provide explicit biological and mechanistic evidence at doses under 2 Gy. Since the release of the 2011 ICRP statement, the Multidisciplinary European Low Dose Initiative (MELODI) supported in April 2019 a scientific workshop that aimed to review epidemiological, clinical and biological evidence for radiation-induced cataracts. The purpose of this article is to present and discuss recent related epidemiological and clinical studies, ophthalmic examination techniques, biological and mechanistic knowledge, and to identify research gaps, towards the implementation of a research strategy for future studies on radiation-induced lens opacities. The authors recommend particularly to study the effect of ionizing radiation on the lens in the context of the wider, systemic effects, including in the retina, brain and other organs, and as such cataract is recommended to be studied as part of larger scale programs focused on multiple radiation health effects.

Lens opacity prevalence among the residents in high natural background radiation area in Yangjiang, China

The aim of the study was to evaluate the risk and threshold doses of lens opacity among residents exposed to low-dose radiation. Residents aged ≥45 years were recruited from a high natural background radiation (HNBR) area in Yangjiang City and a control area selected from nearby Enping City. Lens opacities (LOPs) were classified according to the Lens Opacities Classification System (LOCS) III system. Face-to-face interviews were conducted to collect information on lifestyles, migration and medical history. Life-time cumulative doses were estimated using gender, age, occupancy factors and environmental radiation doses received indoors and outdoors. Logistic regression analyses were conducted to estimate the dose response and determine thresholds. In the HNBR area, among 479 study participants, 101 (21.1%), 245(51.1%) and 23 cases (4.8%), respectively, of cortical, nuclear and posterior subcapsular (PSC) LOPs were found. In the control area, those types of LOPs were identified among 58 cases (12.6%), 206 cases (51.2%) and 6 cases (1.3%) of 462 examinees, respectively. Cumulative eye lens dose was estimated to be 189.5 ± 36.5 mGy in the HNBR area. Logistic analyses gave odds ratios at 100 mGy of 1.26 [95% confidence interval (CI) 1.00-1.60], 0.81 (95% CI 0.64-1.01) and 1.73 (95% CI 1.05-2.85) for cortical, nuclear and PSC LOPs, respectively. For cortical LOPs, a logistic analysis with a threshold dose gave a threshold estimate of 140 mGy (90% CI 110-160 mGy). The results indicated that population exposed to life-time, low-dose-rate environmental radiation was at an elevated risk of cortical and PSC LOPs. A statistically significant threshold dose was obtained for cortical LOPs and no threshold dose for PSC LOPs.

Retrosigmoid Approach in the Supine Position Using ORBEYE: A Consecutive Series of 14 Cases

One of the merits of recently introduced exoscopes, including ORBEYE, is that they are superior to a conventional microscope in terms of ergonomic features. Taking advantage of it, the retrosigmoid approach can be performed in the supine position using ORBEYE. We report a consecutive series of 14 operations through the retrosigmoid approach in the supine position using ORBEYE. Fourteen consecutive patients who underwent surgery through the retrosigmoid approach for cerebellopontine (CP) angle lesions in the supine position using ORBEYE were targeted, and surgical outcomes and complications were examined. We evaluated the posture of the operator and the surgical field during this approach compared with those using a conventional microscope. In all 14 cases, all operative procedures were accomplished only using the ORBEYE. There were no operative complications due to this approach. Using ORBEYE, even when the angle of the operative visual axis was horizontal, the operators could manipulate in a comfortable posture. They were not forced to be in an uncomfortable posture that extended their arms, as is often the case with a conventional microscope. Therefore, they could use shorter surgical instruments. As the cerebellum shifted downward with gravity even using slight retraction during this approach, the working space of the surgical field was easily secured. Through this approach, the operators can perform stable microsurgery of CP angle lesions in a comfortable posture. This approach can reduce the burden on the operator and the patient, leading to a refined surgical procedure.

Patient Body Mass Index and Occupational Radiation Doses to Circulating Nurses During Coronary Angiography

BACKGROUND

Patient BMI is associated with radiation doses received by interventional cardiologists, yet the association between patient BMI and nurse radiation doses is unknown. This study evaluated the association between patient body mass index (BMI) and nurse radiation doses during coronary angiography.

METHODS

Nurse radiation doses were collected by real-time dosimeters during consecutive coronary angiography procedures and are reported as the personal dose equivalent (H_p10). Patient radiation doses were estimated using dose area product (DAP). Patient BMI was categorized in kg/m² as <25.0, 25.0-29.9, 30.0-34.9, 35.0-39.9, and ≥40. Multiple regression analysis determined procedural factors independently association with nurse radiation doses.

RESULTS

In 643 consecutive coronary angiography procedures, patient radiation doses increased significantly across increasing patient BMI categories (p < 0.001). Compared to a patient BMI <25, a patient BMI ≥40 was associated with a 2.3-fold increase in DAP (p < 0.001). Significant differences were also observed in nurse radiation doses across patient BMI categories (p = 0.036). Compared to a patient BMI <25, a patient BMI ≥40 was associated with a 4.0-fold increase in nurse radiation dose (BMI < 25: 0.3 [0.1, 1.3] μSv; BMI ≥ 40: 1.2 [0.2, 2.9] μSv; p = 0.003). By multiple regression analysis, each 1-unit kg/m² increase in patient BMI was associated with a 3.3% increase in nurse radiation dose (p = 0.002).

CONCLUSIONS

Patient BMI was significantly associated with nurse radiation doses during coronary angiography. These observations may have important implications on nurse radiation safety, especially in the setting of the ongoing obesity epidemic.

Effectiveness of additional X-ray protection devices in reducing scattered radiation in radial intervention: the ESPRESSO randomised trial

AIMS

We aimed to examine the impact of three different radiation protection devices in a real-world setting of radial artery catheterisation.

METHODS AND RESULTS

In an all-comer randomised trial, consecutive coronary radial diagnostic and intervention procedures were assigned in a 1:1:1 ratio to shield-only protection (shield group), shield and overlapping 0.5 mm Pb panel curtain (shield+curtain group) or shield, curtain and additional 75x40 cm, 0.5 mm Pb drape placed across the waist of the patient (shield+curtain+drape group). A total of 614 radial procedures were randomised (n=193 shield, n=220 shield+curtain, n=201 shield+curtain+drape). There were no differences among the groups in patient or procedural characteristics. The primary endpoint (relative exposure ratio between the operators' exposure in μSv and the patient's exposure, dose area product in cGy·cm2) was significantly lower in the shield+curtain+drape group for both the first operator (20% reduction vs shield, 16% vs shield+curtain, p=0.025) and the assistant (39% reduction vs shield, 25% vs shield+curtain, p=0.009).

CONCLUSIONS

The use of an additional drape reduced the radiation exposure of both the first operator and the second operator during routine radial procedures; a shield-attached curtain alone was only partially effective. ClinicalTrials.gov identifier: NCT03634657