Evaluation of robotic catheter technology in complex endovascular intervention

The past four decades have witnessed tremendous strides in the evolution of endovascular devices and techniques. Catheter-based intervention has revolutionized the management of arterial disease allowing treatment of aortic and peripheral pathologies via a minimally invasive approach. Despite the exponential advances in endovascular equipment, devices and techniques, catheter-based endovascular intervention has certain morphological and technological constraints. Complex patient anatomy, technological impediments and suboptimal fluoroscopic imaging, can make endovascular intervention challenging using traditional endovascular means. Conventional endovascular catheters lack active manoeuvrability of the tip. Manual control can hinder overall stability and control at key target areas, leading to significantly prolonged overall procedure and fluoroscopic times. Repeated instrumentation increases the risk of vessel trauma and distal embolization. More importantly, guidewire-catheter skills are not necessarily intuitive but must be developed and are highly dependent on operator skill with long training pathways as a result. Recognizing the pressing need to address some of the limitations of standard catheter technology this thesis aims to evaluate the role of advanced robotic endovascular catheters in the aortic arch and the visceral segment. Clinical use of this technology is currently limited to transvenous cardiac mapping and ablation procedures. A comprehensive pre-clinical comparison and analysis of robotic versus manual catheter techniques is presented to reveal both their advantages and limitations, with particular emphasis on the potential of robotic catheter technology to reduce the manual skill required for complex tasks, improve stability at key target areas, reduce the risk of vessel trauma, embolization and radiation exposure, whilst improving overall operator performance. The worlds first clinical report of robot-assisted aortic aneurysm repair, a “proof - of - concept” resulting from this research, is also presented, and the potential for future advanced applications in order to increase the applicability of endovascular therapy to a larger cohort of patients discussed

Angioplasty, Various Techniques and Challenges in Treatment of Congenital and Acquired Vascular Stenoses

The field of performing transcatheter interventions to treat vascular lesions has exploded over the past 20 years. Not only has the technology changed, especially in the arena of balloon/stent devices, but the techniques of approaching complex lesions has evolved over the past decade. Lesions that no one would have imagined treating back in the 1990's are now being done routinely in the catheterization suite. This book provides an update on the current techniques and devices used to treat a wide variety of lesions. Though, at first, the outward appearance of the topics appears to be varied, they are all related by the common thread of treating vascular lesions. We hope, by publishing this book, to accomplish two things: First, to offer insight from experts in their field to treat, both medically and procedurally, complex vascular lesions that we frequently encounter. Secondly, we hope to promote increased communication between areas of medicine that frequently don't communicate, between adult interventional cardiologists, pediatric interventional cardiologists, interventional radiologists, and neurosurgeons. Much can be learned from our respective colleagues in these areas which can further our own world of interventions

Diagnosis and Treatment of Abdominal and Thoracic Aortic Aneurysms Including the Ascending Aorta and the Aortic Arch

This book considers diagnosis and treatment of abdominal and thoracic aortic aneurysms. It addresses vascular and cardiothoracic surgeons and interventional radiologists, but also anyone engaged in vascular medicine. The book focuses amongst other things on operations in the ascending aorta and the aortic arch. Surgical procedures in this area have received increasing attention in the last few years and have been subjected to several modifications. Especially the development of interventional radiological endovascular techniques that reduce the invasive nature of surgery as well as complication rates led to rapid advancements. Thoracoabdominal aortic aneurysm (TAAA) repair still remains a challenging operation since it necessitates extended exposure of the aorta and reimplantation of the vital aortic branches. Among possible postoperative complications, spinal cord injury (SCI) seems one of the most formidable morbidities. Strategies for TAAA repair and the best and most reasonable approach to prevent SCI after TAAA repair are presented

A computational fluid dynamics analysis of the distraction forces experienced by stent-grafts following fenestrated Endovascular Aneurysm Repair

Introduction One option for repair of abdominal aortic aneurysms with inadequate length of infrarenal neck is fenestrated Endovascular Aneurysm Repair. Significant complications may be caused by stent-graft migration and component distraction which are both resisted by fixation force and provoked by haemodynamic distraction force. The hypotheses tested in this thesis are that larger angulation of vessels is associated with greater distraction force and that greater distraction force is associated with higher incidence of migration and component distraction. Method Interobserver variation of a new method of angle measurement was compared with the standard method currently in use in our unit. Computer models of complete fenestrated stent-grafts and their individual components (proximal body, distal body and limb extensions) were then constructed based on the postoperative computed tomography scans of 54 patients. Computational Fluid Dynamic analysis in steady state was used to quantify the distraction force acting on each device. Blood pressure was kept constant at 160mmHg and the impact of morphological features upon distraction force was assessed. To test the second hypothesis, patient-specific blood pressures were used to obtain in situ distraction forces that were then related to the incidence of migration and component distraction. Results There were no significant differences between the old and new methods of angle measurement (p=.723, WSR). Inlet cross-sectional area (XSA) exhibited a strong, positive correlation with total RDF in complete stent-grafts, proximal body and distal body components. Outlet angulation ≥45° was significantly associated with greater total RDF in complete stent-grafts and limb extension components (Median total RDF in complete stent-grafts with angle <45° = 2.6N vs 6.2N in those ≥45°, p<.001. Limb extensions: 1.4N vs 2.1N, p=.004, MWU). There was no significant difference between total RDF acting on the proximal or distal bodies that underwent migration or component distraction versus those that did not. Limb extensions that were observed to migrate were exposed to significantly greater total RDF compared to those that did not migrate (Median total RDF 2.9N, range 2.7-6.3N versus 1.6N, range 0.4-3.8N, p=.003, MWU). Conclusions For a given blood pressure XSA was the most important morphological determinant of total RDF. Outlet angulation of complete stent-grafts and limb extensions was associated with significantly greater total RDF. In limb extensions, greater distraction force was significantly associated with migration. The results suggest caution when planning distal seal in ectatic iliac vessels

Editor's Choice – European Society for Vascular Surgery (ESVS) 2023 Clinical Practice Guidelines on Radiation Safety

Funding Information: On behalf of the Public and Community Oversight Group (PCOG) of the Health Protection Research Unit in Chemical and Radiation Threats and Hazards: Ian Wright; John Phipps; Colette Kelly; Robert Goundry; Eve Smyth; Andrew Wood; Paul Dale (also of the Scottish Environment Protection Agency). On behalf of the Society and College of Radiographers Patient Advisory Group: Lynda Johnson; Philip Plant; Michelle Carmichael – Specialist Senior Staff Nurse Guy's and St Thomas’ NHS Foundation trust.Peer reviewe

Editor's Choice – European Society for Vascular Surgery (ESVS) 2023 Clinical Practice Guidelines on Radiation Safety

info:eu-repo/semantics/publishedVersio