Table1_Left atrial appendage sizing for percutaneous closure in virtual reality—a feasibility study.pdf

Background and aimsThe complex and highly variable three-dimensional anatomy of the left atrial appendage (LAA) makes planning and device sizing for interventional occlusion procedures (LAAC) challenging. Several imaging modalities [e.g. echocardiography, multi-slice computed tomography (MSCT)] are used for this purpose. Virtual reality (VR) is an emerging imaging technique to immerse into a three-dimensional left atrium and appendage, offering unprecedented options of visualization and measurement. This study aimed to investigate the feasibility, accuracy and reproducibility of visualizing the LAA in VR for preprocedural planning of LAAC.
Methods and resultsTwenty-one patients (79 ± 7 years, 62% male) who underwent LAAC at University Hospital Düsseldorf were included in our study. A dedicated software generated three-dimensional VR models from preprocedural MSCT imaging data. Conventional measurements of LAA dimensions (ostium, landing zone and depth) using a commercially available software were compared to measurements in VR: MSCT and VR ostium min. (r = 0.93), max. (r = 0.80) and mean (r = 0.88, all p < 0.001) diameters as well as landing zone (LZ) min. (r = 0.84), max. (r = 0.86) and mean diameters (r = 0.90, all p < 0.001) showed strong correlations. Three-dimensional orientation was judged superior by physicians in VR compared to MSCT (p < 0.05).
ConclusionVirtual reality visualization of the left atrium and appendage based on MSCT data is feasible and allows precise and reproducible measurements in planning of LAA occlusion procedures with enhanced 3D orientation. Further studies need to explore additional benefits of three-dimensional visualization for operators in preprocedural planning.

研究背景与研究目的
左心耳（left atrial appendage, LAA）复杂且高度可变的三维解剖结构，使得左心耳封堵术（left atrial appendage occlusion, LAAC）的术前规划与器械尺寸选择颇具挑战。目前临床常用多种成像方式完成该类术前规划，例如超声心动图、多层螺旋计算机断层扫描（multi-slice computed tomography, MSCT）。虚拟现实（Virtual reality, VR）作为一项新兴成像技术，可实现三维左心房及左心耳结构的沉浸式观察，提供前所未有的可视化与测量途径。本研究旨在探究利用虚拟现实技术可视化左心耳以辅助左心耳封堵术术前规划的可行性、准确性与可重复性。

研究方法与结果
本研究纳入了21例于杜塞尔多夫大学医院接受左心耳封堵术的患者，患者平均年龄为79±7岁，男性占比62%。研究人员利用专用软件基于术前多层螺旋CT影像数据生成三维虚拟现实模型。将采用商用软件获取的左心耳常规径线测量值（包括入口、着陆区（landing zone, LZ）及深度）与虚拟现实模型中的测量值进行对比：多层螺旋CT与虚拟现实模型测得的左心耳入口最小直径（相关系数r=0.93）、最大直径（r=0.80）及平均直径（r=0.88，所有P<0.001），以及着陆区最小直径（r=0.84）、最大直径（r=0.86）及平均直径（r=0.90，所有P<0.001）均呈现强相关性。相较于多层螺旋CT，医师们认为虚拟现实模型的三维空间方位展示效果更优（P<0.05）。

结论
基于多层螺旋CT数据的左心房及左心耳虚拟现实可视化技术具备可行性，可在左心耳封堵术术前规划中实现精准且可重复的测量，并优化三维空间方位感知。未来仍需开展更多研究，以探索三维可视化技术在术者术前规划中的额外临床价值。