Effect of a Real-Time Radiation Monitoring Device on Operator Radiation Exposure During Cardiac Catheterization

Differing radiation exposure in scrub technicians and rotating staff in Cardiac catheterization laboratory: occupation matters

BACKGROUND

Radiation exposure is a significant hazard associated with invasive Cardiology, with most studies based on primary operator exposure. This prospective, observational study aimed to find out over lead radiation exposure as effective dose acquired by non-physician staff comprising scrub technicians and rotating staff in the cath laboratory. Effective dose (ED) measured per procedure via Raysafe i2®dosimeter badges worn by both rotating staff and scrub technicians over lead aprons along with dose area product (DAP), fluoroscopy time (FT) and procedure time (PT) in minutes was collected prospectively over forty-six invasive Cardiology procedures.

RESULTS

This study shows that rotating staff acquire higher ED in comparison with their scrub technician colleagues in diagnostic, interventional and electrophysiology cases. However, a statistically significant difference in radiation exposure of both staff groups was demonstrated in diagnostic and interventional Cardiology procedures, with p values of 0.04 and 0.01, respectively.

CONCLUSIONS

These findings highlight occupational role and mobility around fluoroscopic sources as major factors in radiation exposure, which should be addressed within current radiation protection practices.

Assessing and improving radiation safety in cardiac catheterization: a study from Cairo University Hospital

BACKGROUND

Catheter laboratories are high-radiation exposure environments, especially during X-ray procedures like percutaneous transluminal coronary angioplasty and electrophysiological studies. Radiation exposure poses risks of stochastic (e.g., cancer) and deterministic (e.g., skin changes) effects. This study assessed radiation safety and health practices in a cardiac catheterization unit to optimize radiation safety. A cross-sectional study in Cairo University Hospital (March-September 2019) evaluated 700 patients and healthcare workers. Real-time radiation measurements, educational lectures, and radiation protection measures were implemented in three phases. Data on radiation exposure, procedures, and compliance were collected and analyzed.

RESULTS

The total procedure time and fluoroscopy time per cardiologist did not significantly differ between phases, but there was a statistically significant reduction in the mean total cumulative radiation doses between Phase I and Phase III for cardiologists (P = 0.013). Among nurses and technicians, there was no significant difference in radiation doses between the two phases. Significant correlations were found between operators' radiation doses, procedure time, and fluoroscopy time. Patients' radiation doses decreased significantly from Phase I to Phase III, with correlations between dose, procedure time, and gender. Compliance with radiation protection measures was suboptimal.

CONCLUSIONS

Compliance with radiation safety standards in the cardiac catheterization unit at the Cairo University Hospital needs improvement. The study highlights the importance of adhering to radiation safety principles and optimizing protective measures to reduce radiation exposure for both patients and healthcare personnel. Despite low compliance, significant reductions in radiation doses were achieved with increased awareness and adherence to specific protection measures. Future efforts should focus on enhancing radiation safety protocols and organ-specific radiation impact assessments.

Educational Experience of Interventional Cardiology Fellows in the United States and Canada

BACKGROUND

The COVID-19 pandemic and iodinated contrast shortage may have affected interventional cardiology (IC) fellowship training.

OBJECTIVES

The aim of this study was to investigate the educational experience of first-year IC fellows in the United States and Canada.

METHODS

A 59-question online survey was conducted among 2021-2022 first-year IC fellows in the United States and Canada.

RESULTS

Of the 360 IC fellows invited to participate, 111 (31%) responded; 95% were from the United States, and 79% were men. Participants were mostly from university programs (70%), spent 61 to 70 hours/week in the hospital, and had an annual percutaneous coronary intervention case number of <200 (5%), 200 to 249 (8%), 250 to 349 (33%), 350 to 499 (39%), 500 to 699 (12%), or ≥700 (3%). For femoral access, a micropuncture needle was used regularly by 89% and ultrasound-guided puncture by 81%, and 43% used vascular closure devices in most cases (>80%). Intravascular ultrasound was performed and interpreted very comfortably by 62% and optical coherence tomography (OCT) by 32%, and 20% did not have access to OCT. Approximately one-third felt very comfortable performing various atherectomy techniques. Covered stents, fat embolization, and coil embolization were used very comfortably by 14%, 4%, and 3%, respectively. Embolic protection devices were used very comfortably by 11% to 24% of IC fellows. Almost one-quarter of fellows (24%) were warned about their high radiation exposure. Eighty-four percent considered IC fellowship somewhat or very stressful, and 16% reported inadequate psychological support.

CONCLUSIONS

This survey highlights opportunities for improvement with regard to the use of intravascular imaging, atherectomy techniques, complication prevention and management strategies, radiation awareness and mitigation, and psychological support.

Understanding radiation exposure and improving safety for vascular surgery trainees

OBJECTIVE

Despite having robust radiation safety education procedures and policies in place, we discovered that the trainees at our Accreditation Council for Graduate Medical Education-approved integrated vascular surgery residency and fellowship program were exceeding the annual radiation exposure limits. In the present report, we have described our quality improvement project to identify the root causes and implement policies to improve radiation safety education, oversite, and, ultimately, the exposure levels of our trainees.

METHODS

A committee of faculty, fellows, radiology nurses, and radiation safety officers from each of the programs affiliated hospitals convened to identify the potential root causes of the increased radiation exposure and potential modifiable actions. The radiation exposure reports for postgraduate year 4 to 7 trainees were evaluated before and after the interventions.

RESULTS

Excessive radiation exposure was found to be more prevalent than anticipated, with multiple trainees surpassing the annual exposure limits. The committee classified the factors at play and interventions into four categories: policies and procedures, curriculum, environment, resources, and equipment. The multisite status of our program was a key factor associated with the increased radiation exposure. In addition, we found that excessive radiation levels were occurring primarily at a single hospital site. After the interventions, the monthly average levels at this site had decreased considerably from 936 mrem to 272 mrem.

CONCLUSIONS

We found it alarming that the safety policies in place at vascular residency and fellowship programs were inadequate in securing the safety of their trainees. We found interventions such as inventorying and ensuring the availability of safety equipment, hands-on instruction to complement traditional didactics, lowering the default frame rates, and converting to real-time dosimetry to be effective measures for reducing radiation exposure.

Effect of Different Anthropometric Body Indexes on Radiation Exposure in Patients Undergoing Cardiac Catheterisation and Percutaneous Coronary Intervention

Background: Patient factors, such as sex and body mass index (BMI), are known to influence patient radiation exposure. Body surface area (BSA) and its association with patient radiation exposure has not been well studied. Methods and Results: We analysed height, weight, BMI and BSA in consecutive patients undergoing cardiac catheterisation and percutaneous coronary intervention (PCI) at a high-volume Australian centre between September 2016 and April 2020 to assess their association with dose–area product (DAP, Gycm²). The mean age of the cohort was 64.5 ± 12.3 years with males comprising 68.8% (n = 8100, 5124 diagnostic cardiac catheterisation cases and 2976 PCI cases). Median male BMI was 28.4 kg/m² [IQR 25.2–32.1] versus 28.8 kg/m² [24.7–33.7] for females, p = 0.01. Males had higher BSA (2.0 ± 0.2 m²) than females (1.78 ± 0.2 m²), p = 0.001. Each 0.4 m² increase in BSA conferred a 1.32x fold change in DAP (95% CI 1.29–1.36, p ≤ 0.001). Each 5 kg/m² increase in BMI was linked to a 1.13x DAP fold change (1.12–1.14, p ≤ 0.001). Male sex conferred a 1.23x DAP fold change (1.20–1.26, p ≤ 0.001). Multivariable modelling with BMI or BSA explained 14% of DAP variance (R² 0.67 vs. 0.53 for both, p ≤ 0.001). Conclusions: BSA is an important anthropometric measure between the sexes and a key predictor of radiation dose and radiation exposure beyond sex, BMI, and weight.

Occupational doses in interventional angiography after radiological protection training and use of a real-time direct display dosimeter

Vascular x-ray guided interventions are complex and may result in high occupational doses to ionising radiation if staff do not take appropriate actions to minimise their exposure. In this prospective intervention study, ten staff members wore an extra personal dosimeter on the upper body above their regular protective clothing during four consecutive periods. Between each period either additional practical radiological protection training was given or a real-time direct display dosimeter were provided to the staff. Each staff's personal dose equivalent, Hp(10) normalised to the total air kerma-area product for the procedures where each staff were involved, KAPt, was used as the dependent variable. A focus-group interview with the staff were performed about the usefulness of the training and real-time dose rate display system. Our aim was to investigate if the interventions (practical training or real-time dose rate display) did affect the staff doses in the short and long term (five months later). Significant (p < 0.05) reductions of staff doses Hp(10)/KAPt were found after practical radiological protection training, but not after using real-time dose rate displays. Significant reductions were maintained after five months without additional interventions. The results from the focus-group interview indicated that making radiation 'visible', during practical training and usage of real-time direct display dosimeter, made it easier to understand how to act to lower occupational doses.

DOES RADIOLOGICAL PROTECTION TRAINING OR A REAL-TIME STAFF DOSEMETER DISPLAY REDUCE STAFF DOSES DURING X-RAY-GUIDED PULMONARY BRONCHOSCOPY?

X-ray-guided interventions have increased in number and complexity. Mandatory radiological protection training includes both theoretical and practical training sessions. A recent additional training tool is real-time display dosemeters that give direct feedback to staff on their individual dose rates. Ten staff members who regularly perform pulmonary bronchoscopy wore an extra dosemeter during four 2-month periods. We controlled for the patient air kerma area product and the number of procedures in each period. Between periods 1 and 2, radiological training sessions were held and during period 3 the staff used the real-time display system. Focus-group interviews with the staff were held to obtain their opinion about learning radiological protection. We hypothesised that neither training nor the additional real-time dose rate display alters the personal dose equivalent, Hp(d); d = 0.07 and 10 mm. Useful experiences from radiological protection training were obtained, and median staff doses did decrease, however not significantly.

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.

National Survey of Vascular Surgery Residents & Fellows on Radiation Exposure and Safety Practices

OBJECTIVE

The objective of this study was to evaluate radiation safety practices, radiation training, and radiation exposure among senior vascular residents and fellows in ACGME accredited programs across the United States.

METHODS

Anonymous surveys were sent to all ACGME program directors to be distributed to post graduate year 4-7 vascular trainees for completion. Survey questions focused upon program type (single or multiple hospital site), familiarity with their radiation officer, formal radiation training, frequency of radiation feedback, use of safety equipment, and adherence to ALARA principles.

RESULTS

There were a total of 95 respondents (27% response rate). Forty-nine (51.6%) individuals reported they had never met their radiation safety officer. Seventy-four (77.9%) reported that they had received formal radiation safety education. A total of 50 (53%) individuals reported feedback regarding monthly radiation exposure and 24 (25%) trainees reported never having received feedback on radiation exposure levels. All findings were found to be more common among multiple hospital site program respondents CONCLUSION: It should be of significant concern that such a high number of trainees are exceeding radiation exposure limits. Programs should strive to reduce radiation exposure through formal training, provision of safety equipment, modeling by attendings of adherence to ALARA principles, and timely exposure feedback.

Safety and effectiveness of strategies to reduce radiation exposure to proceduralists performing cardiac catheterization procedures: a systematic review

OBJECTIVE

The objective of this systematic review was to synthesize the best available evidence on the effect of various radiation protection strategies on radiation dose received by proceduralists performing cardiac catheterization procedures involving fluoroscopy.

INTRODUCTION

Cardiac catheterization procedures under fluoroscopy are the gold standard diagnostic and treatment method for patients with coronary artery disease. The growing demand of procedures means that proceduralists are being exposed to increasing amounts of radiation, resulting in an increased risk of deterministic and stochastic effects. Standard protective strategies and equipment such as lead garments reduce radiation exposure; however, the evidence surrounding additional equipment is contradictory.

INCLUSION CRITERIA

Randomized controlled trials that compared the use of an additional radiation protection strategy with conventional radiation protection methods were considered for inclusion. The primary outcome of interest was the radiation dose received by the proceduralist during cardiac catheterization procedures.

METHODS

A three-step search was conducted in MEDLINE, CINAHL, Embase, and the Cochrane Library (CENTRAL). Trials published in the English language with adult participants were included. Trials published from database inception until July 2019 were eligible for inclusion. The methodological quality of the included studies was assessed using the JBI critical appraisal checklist for randomized controlled trials. Quantitative data were extracted from the included papers using the JBI data extraction tool. Results that could not be pooled in meta-analysis were reported in a narrative form.

RESULTS

Fifteen randomized controlled trials were included in the review. Six radiation protection strategies were assessed: leaded and unleaded pelvic or arm drapes, transradial protection board, remotely controlled mechanical contrast injector, extension tubing for contrast injection, real-time radiation monitor, and a reduction in frame rate to 7.5 frames per second. Pooled data from two trials demonstrated a statistically significant decrease in the mean radiation dose (P < 0.00001) received by proceduralists performing transfemoral cardiac catheterization on patients who received a leaded pelvic drape compared to standard protection. One trial that compared the use of unleaded pelvic drapes placed on patients compared to standard protection reported a statistically significant decrease (P = 0.004) in the mean radiation dose received by proceduralists.Compared to standard protection, two trials that used unleaded arm drapes for patients, one trial that used a remotely controlled mechanical contrast injector, and one trial that used a transradial protection board demonstrated a statistically significant reduction in the radiation dose received by proceduralists.Similarly, using a frame rate of 7.5 versus 15 frames per second and monitoring radiation dose in real-time radiation significantly lowered the radiation dose received by the proceduralist. One trial demonstrated no statistically significant difference in proceduralist radiation dose among those who used the extension tubing compared to standard protection (P = 1).

CONCLUSIONS

This review provides evidence to support the use of leaded pelvic drapes for patients as an additional radiation protection strategy for proceduralists performing transradial or transfemoral cardiac catheterization. Further studies on the effectiveness of using a lower fluoroscopy frame rate, real-time radiation monitor, and transradial protection board are needed.

RADIATION DOSES TO THE EYE LENS AND FOREHEAD OF INTERVENTIONAL RADIOLOGISTS: HOW HIGH AND ON WHAT GROUNDS?

The aim of the study was to measure and evaluate the radiation dose to the eye lens and forehead of interventional radiologists (IRs). The study included 96 procedures (lower-limb percutaneous transluminal angioplasties, embolisations/chemoembolisations and vertebroplasties) performed by 6 IRs. A set of seven thermoluminescence dosemeters was allocated to each physician. The highest dose per procedure was found for the left eye lens of the primary operator in vertebroplasties (1576 μSv). Left and right eye doses were linearly correlated to left and right forehead doses, respectively. A workload-based estimation of the annual dose to participating IRs revealed that the occupational dose limit for the eye lens can be easily exceeded. The left eye dose of ΙRs must be routinely monitored on a personalised basis. Τhe left eye dose measurement provides a reliable assessment of the ipsilateral forehead dose, along with valid estimations for the right eye and right forehead doses.

Occupational radiation exposure in femoral artery approach is higher than radial artery approach during coronary angiography or percutaneous coronary intervention

Medical radiation exposure is a significant concern for interventional cardiologists (IC). This study was aimed at estimating the radiation exposure of IC operators and assistants in real clinical practice. The radiation exposure of the operator and assistant was evaluated by conducting two types of procedures via coronary angiography (CAG) and percutaneous coronary intervention (PCI) on 1090 patients in 11-cardiovascular centers in Korea. Radiation exposure was measured using an electronic personal dosimeter (EPD). EPD were attached at 3 points on each participant: on the apron on the left anterior chest (A1), under the apron on the sternum (A2), and on the thyroid shield (T). Average radiation exposure (ARE) of operators at A1, A2, and T was 19.219 uSv, 4.398 uSv, and 16.949 uSv during CAG and 68.618 uSv, 15.213 uSv, and 51.197 uSv during PCI, respectively. ARE of assistants at A1, A2, and T was 4.941 uSv, 0.860 uSv, and 5.232 uSv during CAG and 20.517 uSv, 4.455 uSv, and 16.109 uSv during PCI, respectively. AED of operator was 3.4 times greater during PCI than during CAG.

Strategies to Reduce Radiation Exposure in Electrophysiology and Interventional Cardiology

Clinical diagnosis sometimes involves the use of medical instruments that employ ionizing radiation. However, ionizing radiation exposure is a workplace hazard that goes undetected and is detrimental to patients and staff in the catheterization laboratory. Every possible effort should be made to reduce the amount of radiation, including scattered radiation. Implementing radiation dose feedback may have a role in reducing exposure. In medicine, it is important to estimate the potential biologic effects on, and the risk to, an individual. In general, implantation of cardiac resynchronization devices is associated with one of the highest operator exposure doses due to the proximity of the operator to the radiation source. All physicians should work on the principle of as low as reasonably achievable. Methods for reducing radiation exposure must be implemented in the catheterization laboratory. In this article, we review the available tools to lower the radiation exposure dose to the operator during diagnostic, interventional, and electrophysiological cardiac procedures.

Effectiveness of protection strategies for reducing radiation exposure in proceduralists during cardiac catheterization procedures: a systematic review protocol

REVIEW QUESTION

What is the effectiveness of radiation protection strategies for reducing the radiation dose received by the proceduralist during cardiac catheterization procedures?

Optimizing Staff Dose in Fluoroscopy-Guided Interventions by Comparing Clinical Data with Phantom Experiments

PURPOSE

To evaluate conditions for minimizing staff dose in interventional radiology, and to provide an achievable level for radiation exposure reduction.

MATERIALS AND METHODS

Comprehensive phantom experiments were performed in an angiography suite to evaluate the effects of several parameters on operator dose, such as patient body part, radiation shielding, x-ray tube angulation, and acquisition type. Phantom data were compared with operator dose data from clinical procedures (n = 281), which were prospectively acquired with the use of electronic real-time personal dosimeters (PDMs) combined with an automatic dose-tracking system (DoseWise Portal; Philips, Best, The Netherlands). A reference PDM was installed on the C-arm to measure scattered radiation. Operator exposure was calculated relative to this scatter dose.

RESULTS

In phantom experiments and clinical procedures, median operator dose relative to the dose-area product (DAP) was reduced by 81% and 79% in cerebral procedures and abdominal procedures, respectively. The use of radiation shielding decreased operator exposure up to 97% in phantom experiments; however, operator dose data show that this reduction was not fully achieved in clinical practice. Both phantom experiments and clinical procedures showed that the largest contribution to relative operator dose originated from left-anterior-oblique C-arm angulations (59%-75% of clinical operator exposure). Of the various x-ray acquisition types used, fluoroscopy was the main contributor to procedural DAP (49%) and operator dose in clinical procedures (82%).

CONCLUSIONS

Achievable levels for radiation exposure reduction were determined and compared with real-life clinical practice. This generated evidence-based advice on the conditions required for optimal radiation safety.

Cardiology fellows-in-training are exposed to relatively high levels of radiation in the cath lab compared with staff interventional cardiologists-insights from the RECAP trial

Background

Interventional cardiologists are inevitably exposed to low-dose radiation, and consequently are at risk for radiation induced diseases like cataract and left-sided brain tumours. Operator behaviour may possibly be the largest influencer on radiation exposure. We hypothesised that awareness regarding radiation exposure grows as skill and the general experience in the catheterization laboratory increase.

Objectives

In this study we determined the difference in the relative radiation exposure of staff interventional cardiologists compared with cardiology fellows-in-training.

Methods

During this prospective trial the operator’s radiation exposure (E in µSv) was measured at chest height during 766 diagnostic catheterisations and percutaneous coronary interventions. Also, the patient exposure (DAP in mGy·cm²), representing the amount of radiation administered by the operator per procedure, was collected. The primary outcome of this study was the difference in relative exposure between staff interventional cardiologists versus cardiology fellows-in-training (E/DAP).

Results

From January to May 2017, staff interventional cardiologists performed 637 procedures and cardiology fellows-in-training 129 procedures. The performance of relatively complex procedures by staff interventional cardiologists resulted in a 74% higher use of radiation compared with fellows-in-training. Consequently, staff interventional cardiologists were exposed to 50% higher levels of actual radiation exposure. However, when correcting for the complexity of the procedure, by comparing the relative operator exposure (E/DAP), fellows-in-training were exposed to a 34% higher relative exposure compared with staff interventional cardiologists (p = 0.025).

Conclusions

In the current study, when corrected for complexity, cardiology fellows-in-training were exposed to significantly higher radiation levels than staff interventional cardiologists during catheterisation procedures.

Shields and garb for decreasing radiation exposure in the cath lab

INTRODUCTION

Decreasing radiation exposure of the cardiac catheterization laboratory staff is critical for minimizing radiation-related adverse outcomes and can be accomplished by decreasing patient dose and by shielding. Areas covered: protection from ionizing radiation can be achieved with architectural, equipment-mounted, and disposable shields, as well as with personal protective equipment. Expert commentary: Radiation protective aprons are the most commonly used personal protective equipment and provide robust radiation protection but can cause musculoskeletal strain. Use of a thyroid collar is recommended, as is use of 'shin guards', lead glasses and radioprotective caps, although the efficacy of the latter is being debated. Alternatives to lead aprons include shielding suspended from the ceiling and robotic percutaneous coronary intervention. Radiation protective gloves and cream can be used to protect the hands, but the best protection is to not directly expose them to the radiation beam. Devices that provide real time operator radiation dose monitoring can enable real time adjustments in positioning and shield placement, reducing radiation dose. Shielding can be achieved with architectural, equipment-mounted, and disposable shields. Equipment-mounted shielding includes ceiling-suspended shields, table-suspended drapes, and radioabsorbent drapes. Personal protective equipment and shielding should be consistently and judiciously utilized by all catheterization laboratory personnel.

Evaluating strategies for reducing scattered radiation in fixed-imaging hybrid operating suites

OBJECTIVE

High-resolution fixed C-arm fluoroscopic systems allow high-quality endovascular imaging but come at a cost of greater scatter radiation generation and increased occupational exposure for surgeons. The purpose of this study was to evaluate the efficacy of two methods in reducing scattered radiation exposure.

METHODS

There were 164 endovascular cases analyzed in three phases. In phase 1 (P1), baseline radiation exposure was calculated. In phase 2 (P2), staff used real-time radiation dose monitoring (dosimetry badges [RaySafe; Unfors, Hopkinton, Mass]). In phase 3 (P3), a software imaging algorithm was installed that reduced radiation (EcoDose software; Philips Healthcare, Best, The Netherlands).

RESULTS

A total of 72 cases in P1, 34 cases in P2, and 58 cases in P3 were analyzed. Total mean dose-area product decreased across each phase, with statistical significance achieved for P1 vs P3 (mean ± standard error of the mean, 186,173 ± 16,754 mGy/cm² vs 121,536 ± 11,971 mGy/cm²; P = .002) and P2 vs P3 (171,921 ± 26,276 mGy/cm² vs 121,536 ± 11,971 mGy/cm²; P = .04), whereas total mean fluoroscopy time did not significantly differ across any phase. The radiation exposure to the primary operator did not change significantly from P1 to P2 but fell significantly in P3 (0.08 ± 0.02 mSv vs 0.03 ± 0.01 mSv; P = .02). The addition of dose reduction software had the most impact on endovascular aneurysm repair, with reductions in median room dose (P = .03) and primary operator exposure (P2 vs P3; 0.19 ± 0.04 mSv vs 0.03 ± 0.02 mSv; P < .01).

CONCLUSIONS

Dose reduction software may be an effective technique to lower radiation exposure. Implementation of system-based strategies to reduce radiation is needed to reduce lifetime occupational radiation exposure for endovascular staff and to improve patient safety.

Personalized Feedback on Staff Dose in Fluoroscopy-Guided Interventions: A New Era in Radiation Dose Monitoring

PURPOSE

Radiation safety and protection are a key component of fluoroscopy-guided interventions. We hypothesize that providing weekly personal dose feedback will increase radiation awareness and ultimately will lead to optimized behavior. Therefore, we designed and implemented a personalized feedback of procedure and personal doses for medical staff involved in fluoroscopy-guided interventions.

MATERIALS AND METHODS

Medical staff (physicians and technicians, n = 27) involved in fluoroscopy-guided interventions were equipped with electronic personal dose meters (PDMs). Procedure dose data including the dose area product and effective doses from PDMs were prospectively monitored for each consecutive procedure over an 8-month period (n = 1082). A personalized feedback form was designed displaying for each staff individually the personal dose per procedure, as well as relative and cumulative doses. This study consisted of two phases: (1) 1-5th months: Staff did not receive feedback (n = 701) and (2) 6-8th months: Staff received weekly individual dose feedback (n = 381). An anonymous evaluation was performed on the feedback and occupational dose.

RESULTS

Personalized feedback was scored valuable by 76% of the staff and increased radiation dose awareness for 71%. 57 and 52% reported an increased feeling of occupational safety and changing their behavior because of personalized feedback, respectively. For technicians, the normalized dose was significantly lower in the feedback phase compared to the prefeedback phase: [median (IQR) normalized dose (phase 1) 0.12 (0.04-0.50) µSv/Gy cm2 versus (phase 2) 0.08 (0.02-0.24) µSv/Gy cm2, p = 0.002].

CONCLUSION

Personalized dose feedback increases radiation awareness and safety and can be provided to staff involved in fluoroscopy-guided interventions.

Image noise reduction technology reduces radiation in a radial-first cardiac catheterization laboratory

BACKGROUND

Transradial coronary angiography (TRA) has been associated with increased radiation doses. We hypothesized that contemporary image noise reduction technology would reduce radiation doses in the cardiac catheterization laboratory in a typical clinical setting.

METHODS AND RESULTS

We performed a single-center, retrospective analysis of 400 consecutive patients who underwent diagnostic and interventional cardiac catheterizations in a predominantly TRA laboratory with traditional fluoroscopy (N=200) and a new image noise reduction fluoroscopy system (N=200). The primary endpoint was radiation dose (mGy cm²). Secondary endpoints were contrast dose, fluoroscopy times, number of cineangiograms, and radiation dose by operator between the two study periods. Radiation was reduced by 44.7% between the old and new cardiac catheterization laboratory (75.8mGycm²±74.0 vs. 41.9mGycm²±40.7, p<0.0001). Radiation was reduced for both diagnostic procedures (45.9%, p<0.0001) and interventional procedures (37.7%, p<0.0001). There was no statistically significant difference in radiation dose between individual operators (p=0.84). In multivariate analysis, radiation dose remained significantly decreased with the use of the new system (p<0.0001) and was associated with weight (p<0.0001), previous coronary artery bypass grafting (p<0.0007) and greater than 3 stents used (p<0.0004). TRA was used in 90% of all cases in both periods. Compared with a transfemoral approach (TFA), TRA was not associated with higher radiation doses (p=0.20).

CONCLUSIONS

Image noise reduction technology significantly reduces radiation dose in a contemporary radial-first cardiac catheterization clinical practice.

Influences of audible radiation-monitors or radiopaque-pads on operator and patient dose

Real-time awareness of their own radiation exposure reduced operator irradiation. The use of radiopaque pads did not significantly reduce operator irradiation. Real or perceived measures that reduce operator risk may bias clinical decisions toward "more complete" procedures and increase patient dose.

Predictors of Excess Patient Radiation Exposure During Chronic Total Occlusion Coronary Intervention: Insights From a Contemporary Multicentre Registry

BACKGROUND

High patient radiation dose during chronic total occlusion (CTO) percutaneous coronary intervention (PCI) might lead to procedural failure and radiation skin injury.

METHODS

We examined the association between several clinical and angiographic variables on patient air kerma (AK) radiation dose among 748 consecutive CTO PCIs performed at 9 experienced US centres between May 2012 and May 2015.

RESULTS

The mean age was 65 ± 10 years, 87% of patients were men, and 35% had previous coronary artery bypass graft surgery (CABG). Technical and procedural success was 92% and 90%, respectively. The median patient AK dose was 3.40 (interquartile range, 2.00-5.40) Gy and 34% of the patients received > 4.8 Gy (high radiation exposure). In univariable analysis male sex (P = 0.016), high body mass index (P < 0.001), history of hyperlipidemia (P = 0.023), previous CABG (P < 0.001), moderate or severe calcification (P < 0.001), tortuosity (P < 0.001), proximal cap ambiguity (P = 0.001), distal cap at a bifurcation (P = 0.006), longer CTO occlusion length (P < 0.001), blunt/no blunt stump (P < 0.001), and centre (P < 0.001) were associated with higher patient AK dose. In multivariable analysis high body mass index (P < 0.001), previous CABG (P = 0.005), moderate or severe calcification (P = 0.005), longer CTO occlusion length (P < 0.001), and centre (P < 0.001) were independently associated with higher patient AK dose.

CONCLUSIONS

Approximately 1 in 3 patients who undergo CTO PCI receive high AK radiation dose (> 4.8 Gy). Several baseline clinical and angiographic characteristics can help predict the likelihood of high radiation dose and assist with intensifying efforts to reduce radiation exposure for the patient and the operator.

Reducing Radiation Dose in Coronary Angiography and Angioplasty Using Image Noise Reduction Technology

This study sought to quantitatively evaluate the reduction of radiation dose in coronary angiography and angioplasty with the use of image noise reduction technology in a routine clinical setting. Radiation dose data from consecutive 605 coronary procedures (397 consecutive coronary angiograms and 208 consecutive coronary interventions) performed from October 2014 to April 2015 on a coronary angiography system with noise reduction technology (Allura Clarity IQ) were collected. For comparison, radiation dose data from consecutive 695 coronary procedures (435 coronary angiograms and 260 coronary interventions) performed on a conventional coronary angiography system from October 2013 to April 2014 were evaluated. Patient radiation dosage was evaluated based on the cumulative dose area product. Operators and operator practice did not change between the 2 evaluated periods. Patient characteristics were collected to evaluate similarity of patient groups. Image quality was evaluated on a 5-grade scale in 30 patients of each group. There were no significant differences between the 2 evaluated groups in gender, age, weight, and fluoroscopy time (6.8 ± 6.1 vs 6.9 ± 6.3 minutes, not significant). The dose area product was reduced from 3195 ± 2359 to 983 ± 972 cGycm(2) (65%, p <0.001) in coronary angiograms and from 7123 ± 4551 to 2431 ± 1788 cGycm(2) (69%, p <0.001) in coronary interventions using the new noise reduction technology. Image quality was graded as similar between the evaluated systems (4.0 ± 0.7 vs 4.2 ± 0.6, not significant). In conclusion, a new x-ray technology with image noise reduction algorithm provides a substantial reduction in radiation exposure without the need to prolong the procedure or fluoroscopy time.