Navigated CT‐guided interventions

Diagnostic and therapeutic CT‐ guided percutaneous interventions are clinical routine in interventional radiology. Image‐guided navigation systems visualize the internal anatomy during interventions in real time not necessitating continuous image acquisition. Although multiple 3D image‐guidance devices have been developed and used by several surgical disciplines in the last few years, they have not yet been fully applied by the interventional radiologist. The aim of this article is to review the currently performed methods of CT‐guided percutaneous interventions and to discuss the potential benefits of newly developed 3D‐ navigation systems.     

Open-source platforms for navigated image-guided interventions

Navigation technology is changing the clinical standards in medical interventions by making existing procedures more accurate, and new procedures possible. Navigation is based on preoperative or intraoperative imaging combined with 3-dimensional position tracking of interventional tools registered to the images. Research of navigation technology in medical interventions requires significant engineering efforts. The difficulty of developing such complex systems has been limiting the clinical translation of new methods and ideas. A key to the future success of this field is to provide researchers with platforms that allow rapid implementation of applications with minimal resources spent on reimplementing existing system features. A number of platforms have been already developed that can share data in real time through standard interfaces. Complete navigation systems can be built using these platforms using a layered software architecture. In this paper, we review the most popular platforms, and show an effective way to take advantage of them through an example surgical navigation application.     

Novel QCA methodologies and angiographic scores

Coronary angiography remains the gold-standard method for evaluating coronary artery disease and interventional treatments. As percutaneous coronary interventions have advanced, quantitative coronary angiography (QCA) techniques have also evolved in order to provide more accurate assessments of these therapies. Improvements have been made at each step of the QCA process from image acquisition to vessel analysis. In addition, multiple scoring systems have been developed in order to utilize QCA data, both alone and in conjunction with clinical factors, to better stratify patient risk. This article will review the recent advancements in QCA techniques and outcome prediction models.     

Robotic systems for percutaneous needle-guided interventions

Several groups have developed robotic systems for invasive medical procedures. In this article we will focus on selected robotic systems for percutaneous needle-guided interventions using CT or MR imaging. We present six interventional robotic systems designed to work with imaging modalities such as CT, Cone-beam CT and MRI. The details of each system are given along with any phantom, animal, or human trials performed with each particular robot. Although each of these systems has specific features, they are all of great clinical value since they provide very stable needle guidance -- even for angulated approaches, they may allow access to lesions when the width of the CT- or MR- gantry would limit the access for a biopsy needle or other interventional tools such as thermal ablation probes. Then, such a robot may be able to guide the needle into the most promising region of the lesion without the need for a second contrast injection. Thus, more efficacious characterization and treatment, particularly for lesions that are difficult to target, can be anticipated. Although more research and clinical trials are certainly needed, it is, however, our belief that robotic systems will be an important part of future interventions.     

Preparation, assistance and imaging protocols for robotically assisted MR and CT- based procedures.

To achieve millimetre accuracy and targeting precision of instrument positioning during image-guided (MRT and CT) percutaneous interventions, the Institute of Diagnostic Radiology in Basel is using the medical assistance system INNOMOTION developed and manufactured by Innomedic (Herxheim, Germany). The system does not perform the intervention itself but rather provides the correct insertion angle and depth for the physician who stays in control of the process. After successful completion of the learning curve, the system shall substitute all systems currently used for navigation and puncture assistance. In addition to this, the system shall also be applied in surgery, e.g. trauma surgery. During the current learning curve phase, radiologists and manufacturer are combining their expertise and efforts to continually improve the workflow of planning and executing interventions. The following article describes the execution of an intervention in CT and MRT from the point of view of a registered radiology technician.     

Novel Aspects of 3D Echocardiography in Percutaneous Mitral Valve Interventions: Update 2013

The rapidly increasing importance of percutaneous treatment options for mitral valve diseases promotes the demand for reliable periprocedural guidance by transesophageal echocardiographic imaging. For several interventional mitral leaflet repair techniques real-time 3-dimensional transesophageal echocardiographic (RT3D TEE) guidance has been described to be indispensible. RT3DE TEE provides excellent insight into the mitral valve pathology, which improves procedure planning, safe guidance of device navigation and direct assessment of procedural success. For balloon mitral valvuloplasty 3D echocardiography has shown to effectively accelerate the procedure. The complexity of transcatheter mitral valve repair as well as transcatheter closure of paravalvular leakages of mitral valve prosthesis demands accurate evaluation of the target lesion and guidance of the navigation of the device catheter. All these features have recently found to be uniquely provided by three-dimensional echocardiography. The benefits of RT3D TEE led to its recommendation for percutaneous mitral valve repair procedures in current guidelines. This review of recent literature reports current applications and requirements for refinements in using 3D imaging modalities.     

Preparation,assistance and imaging protocols for robotically assisted MR and CT‐ based procedures

To achieve millimetre accuracy and targeting precision of instrument positioning during image‐guided (MRT and CT) percutaneous interventions, the Institute of Diagnostic Radiology in Basel is using the medical assistance system INNOMOTION^? developed and manufactured by Innomedic (Herxheim, Germany). The system does not perform the intervention itself but rather provides the correct insertion angle and depth for the physician who stays in control of the process. After successful completion of the learning curve, the system shall substitute all systems currently used for navigation and puncture assistance. In addition to this, the system shall also be applied in surgery, e.g. trauma surgery. During the current learning curve phase, radiologists and manufacturer are combining their expertise and efforts to continually improve the workflow of planning and executing interventions. The following article describes the execution of an intervention in CT and MRT from the point of view of a registered radiology technician.     

Real-time transesophageal three-dimensional echocardiography for guidance of percutaneous cardiac interventions: first experience

Recently, a new generation of transesophageal echocardiography (TEE) probes with a novel matrix array technique was introduced, allowing three-dimensional (3D) presentation of cardiac structures in real-time. This article aims to describe our first experiences with this new technique in the guidance of percutaneous cardiac interventions in the catheter laboratory. We used a matrix array 3D TEE probe connected to a 3D-capable echocardiographic system. The 3D TEE system provides exact imaging of the pathomorphology of cardiac structures as well as intracardiac catheters and devices in real-time. We applied this innovative technique to monitor percutaneous cardiac interventions in the catheter laboratory, such as atrial septal defect (ASD) or patent foramen ovale (PFO) closures, revalving procedures such as percutaneous transvenous mitral valve annuloplasty (PTMA), aortic valve replacements, and electrophysiological procedures. Our findings demonstrate that real-time 3D TEE provides a novel imaging technique to guide interventions in the catheter laboratory, providing fast and complete information about the underlying pathomorphology, improving spatial orientation, and additionally monitoring online the procedure without loss of image quality. These benefits may accelerate the learning curve and improve confidence of the interventional cardiologist in order to increase safety, accuracy, and efficacy of interventional cardiac procedures.     

Percutaneous Transcatheter Edge-to-Edge MitraClip Technique: A Practical “Step-by-Step” 3-Dimensional Transesophageal Echocardiography Guide

Recent innovations and advancements in 3-dimensional (3D) echocardiography allow for better understanding of anatomic relationships and improve communication with the interventional cardiologist for guidance of catheter-based interventions. The mitral valve lends itself best for imaging with transesophageal echocardiography (TEE). Consequently, the role of 3D TEE in guiding catheter-based mitral interventions has been evolving rapidly. Although several publications have reported on the advantages and role of 3D TEE in guiding one or more of the steps involved in percutaneous mitral valve repair using the MitraClip, none offer a comprehensive and practical user-friendly guide. This review article provides the reader with practical intraprocedural tips on use of 3D TEE to guide all relevant steps involved in the procedure including how to acquire the images needed and what to look for.     

Subhepatic collections complicating laparoscopic cholecystectomy: Percutaneous management

Ten patients with subhepatic fluid collections complicating laparoscopic Cholecystectomy were successfully treated by interventional radiological procedures. The series included five abscesses, three hematomas, one biloma, and one serous collection. Abdominal pain or fever developed from 3 to 21 days after the laparoscopic intervention. All patients were asymptomatic 72 h after percutaneous drainage and there were no complications related to the procedure. Subhepatic fluid accumulations are common findings after laparoscopic cholecystectomies and have been considered an unreliable indicator of infection or other postoperative complications. However, the significance of these collections should not be underestimated in symptomatic patients. In such cases we propose diagnostic aspiration and drainage, when necessary, to safely and promptly establish the precise diagnosis and treatment. More serious complications can be avoided by early percutaneous intervention.     

实时影像虚拟导航系统在肝癌微创治疗中的初步应用

目的 应用实时影像融合虚拟导航技术对常规超声显示不佳的肝癌病灶行经皮肿瘤微创治疗,明确此影像技术的安全性、可行性及临床应用价值.方法 15例患者共22个肝癌病灶接受虚拟导航引导下经皮消融术,并于术后1月内经增强CT/MR评定消融效果.结果 20个病灶完全消融,2个病灶有局部残留.未出现与治疗相关的并发症.结论 实时影像虚拟导航系统能精确定位病灶,引导穿刺和监控治疗,特别对常规超声不显示的肝癌病灶,虚拟导航技术更显示出优越性.     

实时影像虚拟导航系统在肝癌微创治疗中的初步应用

目的 应用实时影像融合虚拟导航技术对常规超声显示不佳的肝癌病灶行经皮肿瘤微创治疗,明确此影像技术的安全性、可行性及临床应用价值.方法 15例患者共22个肝癌病灶接受虚拟导航引导下经皮消融术,并于术后1月内经增强CT/MR评定消融效果.结果 20个病灶完全消融,2个病灶有局部残留.未出现与治疗相关的并发症.结论 实时影像虚拟导航系统能精确定位病灶,引导穿刺和监控治疗,特别对常规超声不显示的肝癌病灶,虚拟导航技术更显示出优越性.     

Uncommon delayed and late complications after percutaneous left atrial appendage closure with Amplatzer® Cardiac Plug

Aims

Percutaneous left atrial appendage closure with Amplatzer^® Cardiac Plug (St. Jude Medical Inc.) for the prevention of stroke in patients with atrial fibrillation is rapidly propagating. We sought to provide additional safety data.

Methods and results

We have screened our database of patients having been treated with Amplatzer^® Cardiac Plug and found 3 cases with uncommon complications that have not been reported previously. One patient experienced an embolisation of the occluder about 12 months after implantation that potentially resulted from mismatch of occluder size and landing zone. Another patient developed cardiac tamponade 9 days after implantation. This case of delayed effusion was probably not a result of interventional trauma, but might have been provoked by scratching of the inner pericardial membrane. A third patient developed a large thrombus in the left atrium which was considered to be caused by injury of the endothelial wall during implantation. The first two cases could be treated by a percutaneous procedure, the last case by cardiac surgery without any sequelae.

Conclusions

Complications after left atrial appendage closure not related to a device-related thrombus can occur later after implantation. With appropriate percutaneous or surgical management these complications can be handled without sequelae.     

Toward Fluoro-Free Interventions: Using Radial Intracardiac Ultrasound for Vascular Navigation

Transcatheter cardiovascular interventions have the advantage of patient safety, reduced surgery time and minimal trauma to the patient's body. Transcathether interventions, which are performed percutaneously, are limited by the lack of direct line of sight with the procedural tools and the patient anatomy. Therefore, such interventional procedures rely heavily on image guidance for navigating toward and delivering therapy at the target site. Vascular navigation via the inferior vena cava, from the groin to the heart, is an imperative part of most transcatheter cardiovascular interventions including heart valve repair surgeries and ablation therapy. Traditionally, the inferior vena cava is navigated using fluoroscopic techniques such as venography and computed tomography venography. These X-ray–based techniques can have detrimental effects on the patient as well as the surgical team, causing increased radiation exposure, leading to risk of cancer, fetal defects and eye cataracts. The use of a heavy lead apron has also been reported to cause back pain and spine issues, thus leading to interventionalist's disc disease. We propose the use of a catheter-based ultrasound augmented with electromagnetic tracking technology to generate a vascular roadmap in real time and perform navigation without harmful radiation. In this pilot study, we used spatially tracked intracardiac echocardiography to reconstruct a vessel from a phantom in a 3-D virtual environment. We illustrate how the proposed ultrasound-based navigation will appear in a virtual environment, by navigating a tracked guidewire within the vessels in the phantom without any radiation-based imaging. The geometric accuracy is assessed using a computed tomography scan of the phantom, with a Dice coefficient of 0.79. The average distance between the surfaces of the two models comes out to be 1.7 ± 1.12 mm.     

心脏三维超声虚拟内窥镜系统导航与介入方法研究

目的通过心脏三维超声虚拟内窥镜系统导航和介入方法研究,旨在探索并建立复杂型先心病虚拟现实环境下观察的规范化"路径"和介入方法。方法采用体绘制技术重建心腔内表面的三维图像,并置感兴趣的心内结构于可视化显示窗中心,键盘操作与人工导航结合使三维重建图像沿着视线方向前进,产生被观察心内结构目标不断靠近观察者和放大的多帧图像。结果系统通过控制鼠标、键盘立体定位,结合VanPraagh"节段分析法"对感兴趣区域观察,使操作者在虚拟心脏内漫游,实现部分心内畸形结构的诊断。对诊断房、室间隔缺损者,应用虚拟介入装置模拟ASD、VSD介入治疗。结论三维超声虚拟内窥镜为先天性心脏病临床诊断、术前模拟介入、手术计划、外科手术导航及计算机辅助医学教学提供了一种新方法。     

Robotics in percutaneous cardiovascular interventions

Introduction: The fundamental technique of performing percutaneous cardiovascular (CV) interventions has remained unchanged and requires operators to wear heavy lead aprons to minimize exposure to ionizing radiation. Robotic technology is now being utilized in interventional cardiology partially as a direct result of the increasing appreciation of the long-term occupational hazards of the field. This review was undertaken to report the clinical outcomes of percutaneous robotic coronary and peripheral vascular interventions.

Areas covered: A systematic literature review of percutaneous robotic CV interventions was undertaken. The safety and feasibility of percutaneous robotically-assisted CV interventions has been validated in simple to complex coronary disease, and iliofemoral disease. Studies have shown that robotically-assisted PCI significantly reduces operator exposure to harmful ionizing radiation without compromising procedural success or clinical efficacy. In addition to the operator benefits, robotically-assisted intervention has the potential for patient advantages by allowing more accurate lesion length measurement, precise stent placement and lower patient radiation exposure. However, further investigation is required to fully elucidate these potential benefits.

Expert commentary: Incremental improvement in robotic technology and telecommunications would enable treatment of an even broader patient population, and potentially provide remote robotic PCI.     

The Role of Imaging in the Management of Cystic Formations of the Mobile Spine (CYFMOS)

Purpose of Review

The purpose of this review is to give a better understanding of the pathogenesis of cystic formations of the mobile spine (CYFMOS) and the correlating imaging findings. This would help with medical decision-making, given the plethora of conservative, interventional, and surgical treatment options.

Recent Findings

There has been a general understanding that CYFMOS are associated with degenerative spine changes. More recent articles however have suggested that identifying detailed imaging characteristics can assist in determining outcomes when CYFMOS are treated with interventional percutaneous methods or surgical decompression with or without concomitant fusion.

Summary

CYFMOS although uncommon are not a rare finding seen in the spine when there is a background of degenerative spine changes. These cystic lesions are generally symptomatic by exhibiting mass effect on adjacent structure. Most treatments are aimed at decompression by interventional percutaneous or surgical means. Various imaging characteristics of these CYFMOS described in this article including their signal intensity, presence of spinal instability, particular patterns of adjacent degenerative changes, and imaging changes following interventional treatments can help guide physicians when managing these cases.

     

中国先天性心脏病介入治疗发展历程

先天性心脏病(下文简称"先心病")是我国最常见的先天性畸形.经过50余年的发展,我国先心病治疗已历经从传统开胸手术,到经皮导管介入治疗;从最初的球囊导管房间隔造口术的姑息性手术,到封堵缺损、狭窄瓣膜与血管球囊扩张及支架植入的根治性手术;从单一学科治疗,到内外科镶嵌的综合治疗模式的转变.随着具有中国特色自主研发的国产器材...