A Multicenter Survey of Endovascular Theatre Equipment and Radiation Exposure in France during Iliac Procedures

Development, Feasibility, and Knowledge Impact of a Massive Open Online Course on Radiation Safety: A Multicentre Prospective Cohort Study

OBJECTIVE

This study reports the development of an innovative, interactive Massive Open Online Course (MOOC) teaching radiation safety principles in the vascular workplace, using stepwise e-learning with multiple choice question tests (MCQs), educational videos, and a serious game. The aim was to study the MOOC impact on radiation safety knowledge and assess its feasibility and acceptability.

METHODS

An international multicentre prospective study included team members active in the hybrid operating room. The MOOC was offered voluntarily via a secure online learning platform. A standardised MCQ test (15 questions) assessed radiation safety knowledge pre- and post-course (range 0 - 100%). Acceptability and feasibility were tested via the previously validated, Evaluating e-learning system success (EESS) model, using five point Likert scales.

RESULTS

In eight centres across four countries, 150 of 203 invited endovascular team members consented. Over a seven week study period, surgeons (28%, including vascular surgery trainees and consultants), nurses (27%, including scrub, circulating and anaesthetic nurses), anaesthetists (43%, including trainees and consultants), and radiographers (3%) participated. Of those, 67% completed the course. The average radiation knowledge improved by 22.8% (95% CI 19.5 - 26.0%; p < .001) after MOOC completion, from 48% to 71% (standard deviation [SD] 14 and 15% respectively), requiring a mean time investment of 169 minutes (SD 89 minutes). In centres with a radiographer, mean knowledge gain after MOOC completion was significantly smaller (14%, SD 19% vs. 24%, SD 16%, p = .036). The course was deemed feasible and acceptable according to the EESS model with a total mean score of 3.68/5.

CONCLUSION

This newly developed, multimodal MOOC was deemed feasible and effective across multiple international centres. The MOOC significantly contributes to radiation safety education of the entire endovascular team, improving radiation safety knowledge. The course may optimise workplace radiation safety behaviour and therefore enhance team and patient safety.

Radiation Exposure in Endovascular Surgery According to Complexity: Protocol for a Prospective Observational Study

In the past decades, we have witnessed tremendous developments in endovascular surgery. Nowadays, highly complex procedures are performed by minimally invasive means. A key point is equipment improvement. Modern C-arms provide advanced imaging capabilities, facilitating endovascular navigation with an adequate open surgical environment. Nevertheless, radiation exposure remains an issue of concern. This study aims to analyze radiation used during endovascular procedures according to complexity, comparing a mobile X-ray system with a hybrid room (fixed X-ray system). This is an observational and prospective study based on a cohort of non-randomized patients treated by endovascular procedures in a Vascular Surgery department using two imaging systems. The study is planned for a 3-year duration with a recruitment period of 30 months (beginning 20 July 2021) and a 1-month follow-up period for each patient. This is the first prospective study designed to describe the radiation dose according to the complexity of the procedure. Another strength of this study is that radiologic variables are obtained directly from the C-arm and no additional measurements are required for feasibility benefit. The results from this study will help us determine the level of radiation in different endovascular procedures, in view of their complexity.

Fusion imaging guidance for endovascular recanalization of peripheral occlusive disease

OBJECTIVE

Endovascular procedures are now the first line option for treatment of lower extremity arterial disease. Fusion imaging guidance has been reported to reduce radiation exposure and reintervention rates during fenestrated and branched endovascular repairs, but limited literature exists on its benefits during lower extremity arterial disease endovascular procedures, and more specifically peripheral occlusive disease (POD). This study aims to evaluate the radiation exposure and technical success benefits of fusion imaging guidance in a large cohort of patients treated endovascularly for complex POD.

METHODS

From January 2017 to September 2019, in a single center, all consecutive patients presenting symptomatic occlusions (Rutherford Baker categories 3 to 6) in the setting of POD and treated endovascularly were retrospectively assessed for inclusion. All procedures were performed under augmented fluoroscopy guidance (Vessel ASSIST, GE Healthcare), overlaying on live imaging the 3D path for transluminal recanalization based on the preoperative computed tomography angiography. Technical success, dose area product (DAP), total cumulated air kerma (CAK), and fluoroscopy time were collected. DAP results were compared with the literature.

RESULTS

During the study period, 179 patients were treated for iliac (n = 56) or femoropopliteal (n = 123) symptomatic arterial occlusions. Technical success was reported in 171 of 179 procedures (95.5%). The use of a re-entry catheter was required to achieve technical success in 11 patients (6.1%). Mean DAP and CAK were 15.44 Gy·cm² and 135 mGy, respectively, with a mean fluoroscopy time of 15.04 minutes. DAP and CAK were significantly higher in the iliac group when compared with the femoropopliteal group, although fluoroscopy time was not significantly different. DAP was lower than levels reported in the literature.

CONCLUSIONS

Routine use of fusion imaging guidance during POD endovascular treatment is associated with low radiation exposure, high technical success, and reduced need for re-entry systems.

Patient exposure and diagnostic reference levels in operating rooms: a multi-centric retrospective study in over 150 private and public French clinics

To investigate patient exposure in operating rooms and establish Diagnostic Reference Levels (DRLs), fifteen different procedures and nearly 4500 surgeries performed between January 2017 and December 2019 at over 150 different private (79% of data) and public (21% of data) French clinics were recorded. Collected information include the used C-arm equipment, exposure parameters (kVp, mAs, Fluoroscopy Time - FT and Air Kerma-Area Product - PKA) and patient Body Mass Index (BMI) whenever available. Multi-centric DRLs were derived as the 75th percentile of the median exposure data collected in more than 10 different hospitals. For the less frequent procedures, DRLs were determined as the 75th percentile of pooled exposure data with a minimum of 4 centres and 100 patients. Patient exposure proved to be significantly different among the centres. Highest DRLs were found for Abdominal Aortic Aneurysm Endoprosthesis (18 min, 81 Gy cm2), Iliac Angioplasty (6 min, 24 Gy cm2) and Flutter Ablation surgeries (17 min, 14 Gy cm2). In opposition, lowest DRLs were obtained for Hallux Valgus (0.4 min, 0.04 Gy cm2), Hand/Wrist Fracture (0.6 min, 0.16 Gy cm2), and Venous Access Device Implantation surgeries (0.3 min, 0.36 Gy cm2). Similar exposure levels are registered in private clinics and public hospitals. Multi-centric DRLs for fifteen surgical procedures including six new reference values were established to help optimise patients' radiation protection.

A Novel Universal Endovascular Robot for Peripheral Arterial Stent-Assisted Angioplasty: Initial Experimental Results

BACKGROUND

The bottleneck of the development of endovascular interventional robot is that it cannot fully adapt to commercialized endovascular devices, such as guidewires, catheters, and stents, and cannot complete the entire procedure of endovascular treatment, for instance, stent implantation. The purpose of this study is to evaluate whether the novel universal endovascular interventional robot can adapt to different commercialized endovascular devices and accomplish the entire procedure of endovascular treatment of peripheral vascular disease.

METHODS AND MATERIAL

The novel universal endovascular interventional robot consists of 2 components: a master surgeon console and a robotic platform with 4 manipulators. An adult pig was served as the experimental animal. Bilateral iliac artery stent implantation was performed on the pig by the endovascular interventional robot using commercialized guidewires, catheters, and stent delivery systems.

RESULTS

The novel universal endovascular interventional robot can adapt to commercialized endovascular devices, and most interventional procedures, such as insertion, withdrawal, and rotating, can be done through remote control. By coordinating multiple manipulators, complex actions such as superselection, crossing action, or implantation of self-expanding bare stent can be realized. The entire procedure took about 50 minutes, and the total exposure time of the surgeon was less than 1 minute. Postoperative angiography showed that the position of the stent grafts was accurate. The procedure was stable without any stent or surgical-related complications.

CONCLUSION

The novel universal endovascular interventional robot can realize peripheral arterial stent-assisted angioplasty with commercialized devices. Through the design improvement, the problem related to stent implantation is solved, and the remote operation is realized throughout the endovascular procedure.

Endovascular Infrarenal Aortic Aneurysm Repair Performed in a Hybrid Operating Room Versus Conventional Operating Room Using a C-Arm

BACKGROUND

To compare contrast usage and radiation exposure during endovascular aneurysm repair (EVAR) using mobile C-arm imaging in a conventional operating room (OR) or fixed angiographic equipment in a hybrid OR (HR).

METHODS

A retrospective unicenter study from May 2016 to August 2019. All consecutive patients undergoing standard EVAR were included. Patients were divided into 2 groups. Group OR included EVARs performed in a conventional OR with a mobile C-arm (May 2016 to April 2018) and group HR included EVARs performed with a fixed angiographic equipment in an HR (May 2018 to August 2019). Data collected included patient demographics, aneurysm diameter, neck length, radiation dose: median dose-area product (DAP), fluoroscopy time, total operative time, contrast use, and 30-day clinical outcomes.

RESULTS

A total of 77 patients were included in the study (42 patients in group OR and 35 patients in group HR). There was no difference in age, body mass index (BMI), mean aneurysm, and neck length between groups. Patients in the group HR received less contrast volume (108.6 mL [±41.5] vs. 162.5 mL [±52.6]; P < 0.001), but higher radiation dose (154 Gy cm² [±102.9] vs. 61.5 Gy cm² [±42.4]; P < 0.001). There were no differences in fluoroscopy time (20.4 min [±8.5] vs. 23.2 min [±12.4]; P = 0.274) and total operative time (106.4 [±22.3] vs. 109.4 [±25.8]; P = 0.798). No difference was found in terms of 30-day complication rates or operative mortality between groups. DAP was positively correlated with BMI in the group OR (Spearman's rank correlation coefficient r_s, 0.580; P < 0.001), but no correlation could be seen in the group HR (r_s, 0.408; P = 0.028).

CONCLUSIONS

Routine EVAR performed in a hybrid fixed-imaging suite may be associated with less contrast usage, but higher radiation exposure in our center. The significantly higher radiation exposure when the mobile C-arm is replaced by an HR should not be underestimated.

Optimizing imaging and reducing radiation exposure during complex aortic endovascular procedures

Improvements in endovascular technologies and development of custom-made fenestrated and branched endografts currently allow clinicians to treat complex aortic lesions such as thoraco-abdominal and aortic arch aneurysms once treatable with open repair only. These advances are leading to an increase in the complexity of endovascular procedures which can cause long operation times and high levels of radiation exposure. This in turn places pressure on the vascular surgery community to display more superior interventional skills and radiological practices. Advanced imaging technology in this context represents a strong pillar in the treatment toolbox for delivering the best care at the lowest risk level. Delivering the best patient care while managing the radiation and iodine contrast media risks, especially in frail and renal impaired populations, is the challenge aortic surgeons are facing. Modern hybrid rooms are equipped with a wide range of new imaging applications such as fusion imaging and cone-beam computed tomography (CBCT). If these technologies contribute to reducing radiation, they can be complex and intimidating to master. The aim of this review is to discuss the fundamentals of good radiological practices and to describe the various imaging tools available to the aortic surgeon, both those available today and those we anticipate will be available in the near future, from equipment to software, to perform safe and efficient complex endovascular procedures.