Randomized Controlled Trial of Radiation Protection With a Patient Lead Shield and a Novel, Nonlead Surgical Cap for Operators Performing Coronary Angiography or Intervention

Trends in the use of radiation protection and radiation exposure of European endourologists: a prospective trial from the EULIS-YAU Endourology Group

INTRODUCTION

Due to the radiation exposure for the urology staff during endourology, our aim was to evaluate the trends of radiation protection in the operation room by endourologists from European centers and to estimate their annual radiation.

METHODS

We conducted a multicenter study involving experienced endourologists from different European centers to evaluate whether the protection and threshold doses recommended by the International Commission on Radiation Protection (ICRP) were being followed. A 36-question survey was completed on the use of fluoroscopy and radiation protection. Annual prospective data from chest, extremities, and eye dosimeters were collected during a 4-year period (2017-2020).

RESULTS

Ten endourologists participated. Most surgeons use lead aprons and thyroid shield (9/10 and 10/10), while leaded gloves and caps are rarely used (2/10 both). Six out of ten surgeons wear leaded glasses. There is widespread use of personal chest dosimeters under the apron (9/10), and only 5/10 use a wrist or ring dosimeter and 4 use an eye dosimeter. Two endourologists use the ALARA protocol. The use of ultrasound and fluoroscopy during PCNL puncture was reported by 8 surgeons. The mean number of PCNL and URS per year was 30.9 (SD 19.9) and 147 (SD 151.9). The mean chest radiation was 1.35 mSv per year and 0.007 mSv per procedure. Mean radiation exposure per year in the eyes and extremities was 1.63 and 11.5 mSv.

CONCLUSIONS

Endourologists did not exceed the threshold doses for radiation exposure to the chest, extremities and lens. Furthermore, the ALARA protocol manages to reduce radiation exposure.

Operator Intracranial Dose Protection During Fluoroscopic-Guided Interventions

PURPOSE

We utilized an anthropomorphic model made with a human skull to determine how different personal protective equipment influence operator intracranial radiation absorbed dose.

MATERIALS AND METHODS

A custom anthropomorphic phantom made with a human skull coated with polyurethane rubber, mimicking superficial tissues, and was mounted onto a plastic thorax. To simulate scatter, an acrylic plastic scatter phantom was placed onto the fluoroscopic table with a 1.5 mm lead apron on top. Two Radcal radiation detectors were utilized; one inside of the skull and a second outside. Fluoroscopic exposures were performed with and without radiation protective equipment in AP, 45-degree RAO, and 45-degree LAO projections.

RESULTS

The skull and soft tissues reduce intracranial radiation by 76% when compared to radiation outside the skull. LAO (308.95 μSv/min) and RAO projections (96.47μSv/min) result in significantly higher radiation exposure to the primary operator when compared to an AP projection (54 μSv/min). All tested radiation protection equipment demonstrated various reduction in intracranial radiation when compared to no protection. The hood (68% reduction in AP, 91% LAO, and 43% in RAO), full cover (53% reduction in AP, 76% in LAO, and 54% in RAO), and open top with ear coverage (43% reduction in AP, 77% reduction in LAO, and 22% in RAO) demonstrated the most reduction in intracranial radiation when compared to the control.

CONCLUSION

All tested equipment provided various degrees of additional intracranial protection. The skull and soft tissues attenuate a portion of intracranial radiation.

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.

Effect of an optimized X-ray blanket design on operator radiation dose in cardiac catheterization based on real-world angiography

Background

There is increasing concern and focus in the interventional cardiology community on potential long term health issues related to radiation exposure and heavy wearable protection. Optimized shielding measures may reduce operator dose to levels where lighter radioprotective garments can safely be used, or even omitted. X-ray blankets (XRB) are commercially available but suffer from small size and lack of stability. A larger XRB may reduce operator dose but could hamper vascular access and visualization. The aim of this study is to assess shielding effect of an optimized XRB during cardiac catheterization and estimate the potential reduction in annual operator dose based on DICOM Radiation Dose Structured Report (RDSR) data reflecting everyday clinical practice.

Methods

Data accumulated from 7681 procedures over three years in our RDSR repository was used to identify projection angles and radiation doses during cardiac catheterization. Using an anthropomorphic phantom and a scatter radiation detector, radiation dose to the operator (mSv) and patient (dose area product—DAP) was measured for each angiographic projection for three different shielding setups. Relative operator dose (mSv/DAP) was calculated and multiplied by DAP per projection to estimate effect on operator dose.

Results

Adding an optimized XRB to a standard shielding setup comprising a table- and ceiling-mounted shield resulted in a 94.9% reduction in estimated operator dose. The largest shielding effect was observed in left and cranial projections where the ceiling-mounted shield offered less protection.

Conclusions

An optimized XRB is a simple shielding measure that has the potential to reduce operator dose.

CURRENT TRENDS OF RADIATION PROTECTION EQUIPMENT IN INTERVENTIONAL RADIOLOGY

Interventional radiology represents subspecialty of radiology, which does not use imaging modalities only for diagnostics, but mostly for therapeutic purposes. Realisation of interventional procedures is done through X-rays, which replaces direct visual control done by interventional radiologist or cardiologist. For the targeted reduction of the radiation exposure, the interventional radiology staff use personal protective equipment. Usually, aprons with lead-equivalent are used, which provide protection for 75% of the radiosensitive organs. As the eye lens and thyroid gland belong to the radiosensitive organs, lead eyeglasses and thyroid collar are commonly used for their protection. Cap and gloves with lead-equivalent can be utilised as an additional personal protective equipment, that is commercially available. Innovative protection systems, such as mobile radiation protection cabin and suspended radiation protection, have been designed to ensure better radiation protection and safety. These systems provide the comfort for the interventional radiologists at work, while offering better protection against ionising radiation.

Development of a New Radiation Shield for the Face and Neck of IVR Physicians

Interventional radiology (IVR) procedures are associated with increased radiation exposure and injury risk. Furthermore, radiation eye injury (i.e., cataract) in IVR staff have also been reported. It is crucial to protect the eyes of IVR physicians from X-ray radiation exposure. Many IVR physicians use protective Pb eyeglasses to reduce occupational eye exposure. However, the shielding effects of Pb eyeglasses are inadequate. We developed a novel shield for the face (including eyes) of IVR physicians. The novel shield consists of a neck and face guard (0.25 mm Pb-equivalent rubber sheet, nonlead protective sheet). The face shield is positioned on the left side of the IVR physician. We assessed the shielding effects of the novel shield using a phantom in the IVR X-ray system; a radiophotoluminescence dosimeter was used to measure the radiation exposure. In this phantom study, the effectiveness of the novel device for protecting against radiation was greater than 80% in almost all measurement situations, including in terms of eye lens exposure. A large amount of scattered radiation reaches the left side of IVR physicians. The novel radiation shield effectively protects the left side of the physician from this scattered radiation. Thus, the device can be used to protect the face and eyes of IVR physicians from occupational radiation exposure. The novel device will be useful for protecting the face (including eyes) of IVR physicians from radiation, and thus could reduce the rate of radiation injury. Based on the positive results of this phantom study, we plan to perform a clinical experiment to further test the utility of this novel radiation shield for IVR physicians.

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.

Efficacy of MAVIG X-Ray Protective Drapes in Reducing CTO Operator Radiation

Background

The MAVIG X-ray protective drape (MXPD) has been shown to reduce operator radiation dose during percutaneous coronary interventions (PCI). Whether MXPDs are also effective in reducing operator radiation during chronic total occlusion (CTO) PCI, often with dual access, is unknown.

Methods

We performed a prospective, randomized-controlled study comparing operator radiation dose during CTO PCI (n = 60) with or without pelvic MXPDs. The primary outcomes were the difference in first operator radiation dose (μSv) and relative dose of the first operator (radiation dose normalized for dose area product) at the level of the chest in the two groups. The effectiveness of MXPD in CTO PCI was compared with non-CTO PCI using a patient-level pooled analysis with a previously published non-CTO PCI randomized study.

Results

The use of the MXPD was associated with a 37% reduction in operator dose (weighted median dose 26.0 (IQR 10.00–29.47) μSv in the drape group versus 41.8 (IQR 30.82–60.59) μSv in the no drape group; P < 0.001) and a 60% reduction in relative operator dose (median dose 3.5 (IQR 2.5–5.4) E/DAPx10⁻³ in the drape group versus 8.6 (IQR 4.2–12.5) E/DAPx10⁻³ in the no drape group; P=0.001). MXPD was equally effective in reducing operator dose in CTO PCI compared with non-CTO PCI (P value for interaction 0.963).

Conclusions

The pelvic MAVIG X-ray protective drape significantly reduced CTO operator radiation dose. This trial is clinically registered with https://www.clinicaltrials.gov (unique identifier: NCT04285944).

Clinical evaluation of a novel head protection system for interventional radiologists

PURPOSE

A novel two-part protective system consisting of a modified thyroid collar and a head protection is intended to reduce the radiation dose to the examiners head during fluoroscopy-guided interventions. In this pilot study, we tested this protection system under real-life conditions in general radiological and neuroradiological interventions.

METHODS

Two sets of the protection system (set A and B) were equipped with 12 thermoluminiscence detectors (TLD). For simultaneous measurement of radiation exposure and dose-reduction, each six TLDs were fixed to the inner side and on the corresponding outer side of the protection system. Set A was used exclusively for general radiological interventions and set B exclusively for neuroradiological interventions. To compare the staff exposure in general radiology and neuroradiology, dose values were normalized to a DAP of 10 000 µGy∙m².

RESULTS

The sets were tested during 20 general radiological interventions and 32 neuroradiological interventions. In neuroradiology, the mean normalized radiation exposure was 13.44 ± 1.36 µSv/10000 µGy∙m² at the head protection and 22.27 ± 2.09 µSv/10 000 µGy∙m² at the thyroid collar. In general radiology, the corresponding results were 29.91 ± 4.19 µSv/10 000 µGy∙m² (head protection) and 68.07 ± 17.25 µSv/10 000 µGy∙m² (thyroid collar). Thus, mean dose exposure was 2.5 times higher in general radiological interventions (p = 0.016). The use of the protection system resulted in a mean dose reduction of 81.2 ± 11.1 % (general radiology) and 92.1 ± 4.2 % (neuroradiology; p = 0.016).

CONCLUSION

Fluoroscopy-guided interventions lead to significant radiation exposure of the head area for the examiner. The novel protection system tested led to a significant dose reduction of 80-90%, depending on the type of intervention.

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.

Impact of radiation to the eye of operators during endo-cardiovascular surgery and the importance of protection

OBJECTIVE

To verify the amount of radiation exposure to the eye of operators during endocardiovascular surgery (ECVS) in hybrid operating room (HOR), which increases the risk of cataracts in surgeons.

METHODS

Fifty cases of ECVS (including 36 transcatheter aortic valve implantation and 14 thoracic endovascular repair) using the transfemoral approach performed from February 2020 to July 2020 were included. A measurement device was attached to the left side of the head of the operators and their assistants to measure the cumulative dose (CD) of intraoperative radiation exposure. The subjects were divided into the control group (Group C, n = 26), received conventional protection using the protective curtain in HOR and the protected group (Group R, n = 24), received conventional protection and protection sheet. The normalized CD by dose area product (CD/DAP) was evaluated.

RESULTS

The CD/DAP of the surgeons was significantly decreased in Group R, averaging at 5.97 μSV/Gy cm² in Group C group and 4.40 μSV/Gy cm² in Group R (p < 0.01). Moreover, CD/DAP of the assistant was significantly reduced in the Group R, with an average of 1.87 μSV/Gy cm² in the Group C and 1.01 μSV/Gy cm² in Group R (p < 0.01).

CONCLUSIONS

The radiation exposure to the surgeon's eye could be significantly reduced by protection sheet.

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.

Clinical Issues-April 2021

Scrubbed team members leaving the OR while x-rays are taken Key words: radiation source exposure, x-ray, distance and shielding, radiation protection devices, inverse square law. Cleaning radiation protection garments and devices Key words: radiation protection, cleaning reusable garments, eyewear, lead aprons, shielding devices. Implementing radiation precautions for pregnant health care workers Key words: scatter radiation, shielding, dosimeter, pregnant health care worker, protective garment. Protecting patients from radiation exposure Key words: scatter radiation, radiation protection devices, radiation shielding, radiation protection drapes, patient exposure. Wearing x-ray aprons that fit correctly Key words: body size, radiation protection garment sizing, x-ray, lead aprons, anthropomorphic phantom.

Efficacy of MAVIG X-Ray Protective Drapes in Reducing Operator Radiation Dose in the Cardiac Catheterization Laboratory: A Randomized Controlled Trial

BACKGROUND

Interventional cardiologists are occupationally exposed to high doses of ionizing radiation. The MAVIG X-ray protective drape (MXPD) is a commercially available light weight, lead-free shield placed over the pelvic area of patients to minimize operator radiation dose. The aim of this study was to examine the efficacy of the MXPD during routine cardiac catheterization, including percutaneous coronary interventions.

METHODS

We performed a prospective, randomized controlled study comparing operator radiation dose during cardiac catheterization and percutaneous coronary intervention (n=632) with or without pelvic MXPD. We measured operator radiation dose at 4 sites: left eye, chest, left ring finger, and right ring finger. The primary outcomes were the difference in first operator radiation dose (µSv) and relative dose of the first operator (radiation dose normalized for dose area product) at the level of the chest in the 2 groups.

RESULTS

The use of the MXPD was associated with a 50% reduction in operator radiation dose (median dose 30.5 [interquartile range, 23.0-39.7] µSv in no drape group versus 15.3 [interquartile range, 11.1-20.0] µSv in the drape group; P<0.001) and a 57% reduction in relative operator dose (P<0.001). The largest absolute reduction in dose was observed at the left finger (median left finger dose for the no drape group was 104.9 [75.7-137.4] µSv versus 41.9 [32.6-70.6] µSv in the drape group; P<0.001).

CONCLUSIONS

The pelvic MXPD significantly reduces first operator radiation dose during routine cardiac catheterization and percutaneous coronary intervention. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT04285944.

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

Efficiency of the RADPAD Surgical Cap in Reducing Brain Exposure During Pacemaker and Defibrillator Implantation

OBJECTIVES

This study sought to investigate the RADPAD No Brainer (Worldwide Innovation and Technologies, Overland Park, Kansas) efficiency in reducing brain exposure to scattered radiation.

BACKGROUND

Cranial radioprotective caps such as the RADPAD No Brainer are being marketed as devices that significantly reduce operator's brain exposure to scattered radiation. However, the efficiency of the RADPAD No Brainer in reducing brain exposure in clinical practice remains unknown to date.

METHODS

Five electrophysiologists performing device implantations over a 2-month period wore the RADPAD cap with 2 strips of 11 thermoluminescent dosimeter pellets covering the front head above and under the shielded cap. Phantom measurements and Monte Carlo simulations were performed to further investigate brain dose distribution.

RESULTS

Our study showed that the right half of the operators' front head was the most exposed region during left subpectoral device implantation; the RADPAD cap attenuated the skin front-head exposure but provided no protection to the brain. The exposure of the anterior part of the brain was decreased by a factor of 4.5 compared with the front-head skin value thanks to the skull. The RADPAD cap worn as a protruding horizontal plane, however, reduced brain exposure by a factor of 1.7 (interquartile range: 1.3 to 1.9).

CONCLUSIONS

During device implantation, the RADPAD No Brainer decreased the skin front head exposure but had no impact on brain dose distribution. The RADPAD No Brainer worn as a horizontal plane worn around the neck reduces brain exposure and confirms that the exposure comes from upward scattered radiation.

Effectiveness of a radiation protective device for anesthesiologists and transesophageal echocardiography operators in structural heart disease interventions

In structural heart disease (SHD) interventions, the exposure of staff other than the first operator such as anesthesiologists and transesophageal echocardiography (TEE) operators to the radiation can also pose the risks of cancer and cataracts in the long term. This study was conducted to test our new radiation protective device (RPD) for anesthesiologists and TEE operators in SHD interventions. The RPD, which consists of a head side shield and a cradle shield, was mounted on a 0.25 mm Pb-equivalent unleaded radiation protection sheet on a self-made J-shaped acrylic table, and it was placed on the head side and cradle on the operating table. A CT human body phantom was placed on the operating table, and the C-arm was set in five directions: posteroanterior, right anterior oblique 30°, left anterior oblique 30°, caudal 30°, and cranial 30°. The ambient dose equivalent rate at the usual positions of the anesthesiologist and TEE operator were measured under a fluoroscopic sequence with and without the RPD, and the dose reduction rate was obtained. The height of each measurement point was set to 100, 130 or 160 cm. The reduction rates at the positions of the anesthesiologist and the TEE operator were 82.6-86.4% and 77.9-89.5% at the height of 100 cm, 48.5-68.4% and 83.3-91.0% at 130 cm, and 23.6-62.9% and 72.9-86.1% at 160 cm, respectively. The newly developed RPD can thus effectively reduce the radiation exposure of anesthesiologists and TEE operators during SHD interventions.

Radioprotective efficacy of plastic polymer against the toxicogenomic effects of radiopharmaceutical 18F-FDG on human lymphocytes

BACKGROUND

Healthcare workers occupationally exposed to 18F-FDG cannot wear protective equipment, such as lead aprons, since the interaction between high energy radiation (511 keV) and metal increases the dose of radiation absorption. The objective of this study was to evaluate the shielding efficacy of a plastic polymer against the toxicogenomic effects of ionizing radiation in human lymphocytes, using cytokinesis-block micronucleus assays.

METHODS

Human peripheral blood lymphocytes were isolated from three subjects and cultured under standard conditions. The cultures were exposed to 300 mCi of 18F-FDG at a distance of 10 cm for 10 min, in the absence of shielding or with lead, polymer, and lead + polymer shields.

RESULTS

Lead shielding was found to increase the number of counts detected by Geiger-Müller radiation monitors as a consequence of the photoelectron effect. Conversely, the lead + polymer shield reduced the number of counts. The lead, polymer, and lead + polymer shields significantly reduced the frequency of micronuclei, nucleoplasmic bridges, and nuclear buds induced by ionizing radiation. Regarding cytotoxicity, only the lead + polymer shield re-established the cell cycle at the level observed for the negative control.

CONCLUSIONS

Lead aprons that are internally coated with polymer increased the radiological protection of individuals occupationally exposed to 18F-FDG PET/CT, especially during examinations.

Estimating brain radiation dose to the main operator in interventional radiology

The aim of this study was to estimate brain radiation dose to the main operator during interventional radiology procedures. Occupational brain doses from 19 interventional procedures were measured using thermoluminiscent dosimeters and an anthropomorphic RANDO woman phantom simulating a main operator. Results show that, interventional radiologists may receive minimum and maximum brain doses per procedure of 0.01 mGy (left temporal cortex) and 0.08 mGy (temporal lobe cortex), respectively. A radiologist who works without movable shielding devices during procedures and has a typical workload (for example 500 procedures per year), might exceed the new dose threshold of 0.5 Gy for circulatory disease in the brain working 12.6 years of his career.

Vascular access and radiation exposure during percutaneous coronary procedures

In the cardiology community, the use of transradial access for percutaneous coronary procedures is progressively increasing all around the world overtaking the use of transfemoral access. The advantages of the transradial access are based on a significant reduction in bleeding and vascular events compared to the femoral access and on a reduction in mortality in the setting of acute coronary syndromes. However, in recent years a slight but significant increase in radiation exposure for patients and operators associated with the radial approach has been detected, increasing concerns about possible long term increased stochastic risk. In particular interventional cardiologists are among physicians performing interventional procedures using X-rays, those exposed to the highest radiation dose during their activity and this exposure is not without possible long-term clinical consequences in term of deterministic and stochastic effects. All the operators should be aware of these risks and manage to reduce their radiation exposure. In this review we analysed the differences in term of radiation exposure comparing the radial and the femoral access for percutaneous coronary procedures. Then, we discussed the possible clinical consequences of these differences and finally we showed the available tools aimed to reduce the operator radiation exposure. In particular the use of adjunctive protective drapes placed on the patient might reduce operator radiation exposure in up to 81% of the dose.

Radiation protection in the cardiac catheterization laboratory

The trend towards more minimally invasive procedures in the past few decades has resulted in an exponential growth in fluoroscopy-guided catheter-based cardiology procedures. As these techniques are becoming more commonly used and developed, the adverse effects of radiation exposure to the patient, operator, and ancillary staff have been a subject of concern. Although occupational radiation dose limits are being monitored and seldom reached, exposure to chronic, low dose radiation has been shown to have harmful biological effects that are not readily apparent until years after. Given this, it is imperative that reducing radiation dose exposure in the cardiac catheterization laboratory remains a priority. Staff education and training, radiation dose monitoring, ensuring use of proper personal protective equipment, employment of shields, and various procedural techniques in minimizing radiation must always be diligently employed. Special care and consideration should be extended to pregnant women working in the cardiac catheterization laboratory. This review article presents a practical approach to radiation dose management and discusses best practice recommendations in the cardiac catheterization laboratory.

Strategies for Minimizing Occupational Radiation Exposure in Cardiac Imaging

PURPOSE OF REVIEW

Radiation safety has been at the center of interest of both researchers and healthcare institutions. This review will summarize and shed light on the various techniques adapted to reduce staff exposure to ionizing radiation (IR) in the field of cardiac imaging.

RECENT FINDINGS

In the last years, with the advance of awareness and the development of new technologies, there have been several tools and techniques adapted. The breakthrough of several technologies to lower radiation dose and shorten the duration of diagnostic tests associated with IR, the use of protection devices by staff members, and mostly the awareness of exposure to IR are the hallmark of these advances. Using all these measures has led to a significant decrease in staff exposure to IR. Reducing staff exposure to meet the "As Low As Reasonably Achievable" principle is feasible. This review introduces the most important strategies applied in cardiac imaging.

Assessing the level of radiation experienced by anesthesiologists during transfemoral Transcatheter Aortic Valve Implantation and protection by a lead cap

OBJECTIVE

Transfemoral Transcatheter Aortic Valve Implantation (TAVI) has become a standard therapy for patients with aortic valve stenosis. Fluoroscopic imaging is essential for TAVI with the anesthesiologist's workplace close to patient's head side. While the use of lead-caps has been shown to be useful for interventional cardiologists, data are lacking for anesthesiologists.

METHODS

A protective cap with a 0.35 lead-equivalent was worn on 15 working days by one anesthesiologist. Six detectors (three outside, three inside) were analyzed to determine the reduction of radiation. Literature search was conducted between April and October 2018.

RESULTS

In the observational period, 32 TAVI procedures were conducted. A maximum radiation dose of 0.55 mSv was detected by the dosimeters at the outside of the cap. The dosimeters inside the cap, in contrast, displayed a constant radiation dose of 0.08 mSv.

CONCLUSION

The anesthesiologist's head is exposed to significant radiation during TAVI and it can be protected by wearing a lead-cap.

DOSIMETRY DURING PERCUTANEOUS CORONARY INTERVENTIONS OF CHRONIC TOTAL OCCLUSIONS

Percutaneous coronary interventions (PCI) of coronary chronic total occlusions (CTO) increase the risk of high radiation exposure for both the patient and the cardiologist. This study evaluated the maximum dose to the patients' skin (MSD) and the exposure of the cardiologists during CTO-PCI. Moreover, the efficiency of radioprotective drapes to reduce cardiologist exposure was assessed. Patient dose was measured during 31 procedures; dose to the cardiologist's extremities were measured during 65 procedures, among which 31 were performed with radioprotective drapes. The MSD was high (median: 1254 mGy; max: 6528 mGy), and higher than 2 Gy for 33% of the patients. The dose to the cardiologists' extremities per procedure was also of concern (median: 25-465 μSv), particularly to the left eye (median: 68 μSv; max: 187 μSv). Radioprotective drapes reduced the exposure to physician's upper limbs and eyes; especially to the left side (from -28 to -49%).

Determinants of operator radiation exposure during percutaneous coronary procedures

BACKGROUND

Radiation exposure is an important issue for interventional cardiologists that is often underevaluated. Our aim was to evaluate determinants of operator radiation exposure during percutaneous coronary procedures.

METHODS

The RADIANT (NCT01974453) is a prospective, single-center observational study involving 4 expert operators and 2 fellows performing percutaneous coronary procedures. The operator radiation dose was evaluated using dedicated electronic dosimeters in 2,028 procedures: 1,897 transradial access (TRA; 1,120 right and 777 left TRA) and 131 transfemoral access (TFA).

RESULTS

In the whole population, operator radiation dose at the thorax did not differ between TFA (9μSv [interquartile range 5-18μSv]) and TRA (9μSv [4-21μSv]), but after propensity score matching analysis, TFA showed lower dose (9μSv [5-18μSv]) compared with TRA (17μSv [9-28μSv], P<.001). In the whole transradial group, left TRA (5μSv [2-12μSv]) was associated with significant lower operator dose compared with right TRA (13μSv [6-26μSv], P<.001).The use of adjunctive protective pelvic drapes was significantly associated with lower radiation doses compared with procedures performed without drapes (P<.001). Among the operators, an inverse relation between height and dose was observed. Finally, left projections and the use of angiographic systems not dedicated for coronary and high frame rates were all associated with a significant higher operator radiation exposure.

CONCLUSIONS

In a high-volume center for transradial procedures, TFA is associated with lower operator radiation dose compared with TRA. The use of adjunctive anti-rx drapes seems a valuable tool to reduce the higher operator radiation exposure associated with TRA.