IVUS (IntraVascular UltraSound) Image Guidance for Treatment of Aorto-Iliac Pathologies

Ultrasound-based image guidance for endovascular interventions has long been propagated as safe and (cost)-effective in many respects. IVUS guidance has also been shown to be superior to angiographic guidance in aortic disease, both in terms of imaging and radiation reduction.This book discusses the value and potential applications of IVUS in aorto-iliac pathologies. Part I explains the potential risks and side effects of using X-rays for patients and staff. The current status of IVUS imaging and the requirements for successful use of this tool are presented. Part II focuses on when and how to use IVUS guidance in the aortic and pelvic segments. In addition to the presentation of the technical equipment, recommendations are given for the implementation of IVUS in the daily routine and for image generation, procedural sequences and interpretation of the findings based on the display on the IVUS monitor.This book is a useful guide for physicians and other staff members dealing routinely with radiation-based imaging in the operative setting or the angiosuite. It will also raise the reader's awareness for the X-ray-associated risks and available solutions for improving radiation safety in the OR and the procedural and outcome quality.

Part I1.Introduction121.1.US for access to target vessels121.2.US guidance for endovascular procedures131.3.Therapeutic use of US for endovascular reconstruction131.4.Why should we perform IVUS guidance for aortic and aorto-iliac procedures132.Radiation safety issues and risk awareness162.1.Revised radiation safety directives and guidelines 2020-2022162.2.Radiation safety items in the daily routine: staff training162.3.Radiation protection items in the daily routine172.4.Personalized radiation protection equipment182.5.Reduction of the individual radiation exposure202.5.1.Influence of radiation source position and individual behavior202.5.2.Influence of room geometry and procedural workflow on staff radiation exposure212.5.3.Projection angle and radiation safety: steady AP-projection for optimal radiation protection253.Iodinated Contrast Media (ICM) and procedure-related renal side effects303.1.CIN: Contrast-Induced Nephropathy313.1.1.Definition of CIN313.1.2.Pathophysiology of CIN313.1.3.Risk factors for CIN and prevention313.1.4.Differential diagnosis of CIN323.1.5.Strategies for CIN prevention333.1.6.IVUS for CIN prevention333.2.Acute kidney injury vs. CIN344.Software and hardware solutions for radiation dose / contrast mediareduction and workflow improvement374.1.ClarityIQ¿ and image noise reduction374.2.Image fusion solutions374.3.FORS (fiberoptic real shape imaging)384.4.Simulation-based endovascular (and open surgery) radiation protection training38Part II5.IVUS image guidance for endovascular procedures in respect to currentradiation safety guidelines425.1.The revised ESVS radiation guidelines and the role of IVUS425.2.Decision making for IVUS use435.3.What is the current state of IVUS image guidance in the different vascular territories?Why use IVUS at all?445.3.1.IVUS for Percutaneous Coronary Interventions (PCI)445.3.2.IVUS for endovenous procedures445.3.3.IVUS for PAD455.3.4.Non-clinical aspects of IVUS: Cost effectiveness calculations for PVI and PCI455.3.5.IVUS and radiation/procedural safety466.Current technical state of IVUS image guidance506.1.Comparison of IVUS vs. angiographic imaging506.2.Catheter portfolio and technical specifications536.2.1.Technical basics of IV/US imaging536.2.2.IVUS catheter portfolio536.2.3.Technical specifications of IVUS catheters566.2.4.Imaging techniques and image information content596.2.4.1.ChromaFlö596.2.4.2.VH IVUS596.3.Current options for image processing606.3.1.Image processing with Intrasight 5S616.4.Standards of Procedure (SOP) for IVUS use636.4.1.SOP for the hybrid room646.4.2.SOP for the standard operating room (constricted room)656.5.Team challenge IVUS666.5.1.Team challenge IVUS catheter use666.5.2.Team challenge Pioneer Plus catheter use667.IVUS for EVAR697.1.Published IVUS data for TEVAR697.2.What are the key factors for advanced image guidance in TEVAR or aorto-iliac PADprocedures?707.3.Target vessel mapping and sealing zone definition by intraluminal cross-sectional imaging727.3.1.Parallaxes and IVUS737.4.SOPs for IVUS guidance during TEVAR / PAD747.4.1.EVAR-SOP in the local setting747.4.1.1.Vessel access747.4.1.2.Pullback maneuver with IVUS and image processing747.4.1.3.Mapping of the target vessels757.4.1.4.Catheter protection during graft deployment757.4.1.5.IVUS completion control757.4.1.6.Workspace setting for TEVAR / PAD757.5.IVUS image interpretation787.5.1.Image interpretation prior to infrarenal endograft placement797.5.2.Interpretation of IVUS images after endograft deployment (completion of IVUS pullback)837.5.3.Sealing length847.5.4.Endoleak detection with IVUS867.6.IVUS benefits in terms of prevention of early complications877.7.IVUS and radiation safety878.IVUS for TEVAR (for aneurysmal disease, aortic dissections, and otherpathologies)938.1.Where and when IVUS is useful938.2.Procedural pathways and imaging properties for IVUS and angiography in differentpathologies948.3.Available evidence concerning IVUS image guidance for thoracic endograft placement958.4.IVUS imaging quality for the different TEVAR modalities and their challenges998.5.IVUS image guidance workflow and image interpretation998.5.1.Femoral artery access998.5.2.Advancement of devices998.5.3.IVUS vs. CTA centerline998.5.4.IVUS image guidance in dissections: the gold standard for reliability?1008.5.5.Procedural workflow for pathologies in the descending thoracic aorta1058.5.6.Specific findings using IVUS1068.5.7.Advantages of IVUS vs. deficits of angiography in completion imaging1068.5.7.1.Bird beak sign1068.5.7.2.Infolding of grafts1088.5.7.3.Graft crimping1088.5.7.4.Imminent stroke risk of arch angiography1108.5.7.5.Visualization of intra- and extraluminal structures1108.6.Conclusions1139.IVUS image guidance for aortoiliac occlusive disease1169.1.Procedural and clinical outcome of IVUS-guided revascularizations1169.2.Technical requirements and SOPs for IVUS image guidance for arterial occlusive disease1169.2.1.Procedural pathway for IVUS mapping and completion control for aorto-iliac stenosis1179.2.1.1.Procedural steps for IVUS guidance1199.3.Image interpretation1219.4.Radiation safety issues in aorto-iliac procedures1239.5.Conclusions12610.Interpretation and misinterpretation of IVUS images12810.1.Particular problems of IVUS image guidance and dedicated bail-out proposals12810.1.1.Sonic shadow vs. vessel lumen12810.2.Imaging details and decision making12910.3.Orientation for target vessel definition / mapping and exact device12910.3.1.What are ambiguous or unambiguous markers?12910.3.2.Anatomy of the renal vein and misleading interpretation12910.3.3.Artefacts originating from the catheter tip13210.3.4.Artefacts originating from implants13310.3.5.What about orientation and interpretation in severely calcified lesions or after deviceplacement?13310.3.6.Interpretation of dissection vs. artefacts in different vessels13410.3.6.1.IVUS advantages in dissection detection during PAD treatment136