Ai Z, Dech F, Rasmussen M, Silverstein J C
University of Illinois at Chicago, VRMedLab 60612, USA.
Stud Health Technol Inform. 2000;70:4-9.
Since the acquisition of high-resolution three-dimensional patient images has become widespread, medical volumetric datasets (CT or MR) larger than 100 MB and encompassing more than 250 slices are common. It is important to make this patient-specific data quickly available and usable to many specialists at different geographical sites. Web-based systems have been developed to provide volume or surface rendering of medical data over networks with low fidelity, but these cannot adequately handle stereoscopic visualization or huge datasets. State-of-the-art virtual reality techniques and high speed networks have made it possible to create an environment for clinicians geographically distributed to immersively share these massive datasets in real-time. An object-oriented method for instantaneously importing medical volumetric data into Tele-Immersive environments has been developed at the Virtual Reality in Medicine Laboratory (VRMedLab) at the University of Illinois at Chicago (UIC). This networked-VR setup is based on LIMBO, an application framework or template that provides the basic capabilities of Tele-Immersion. We have developed a modular general purpose Tele-Immersion program that automatically combines 3D medical data with the methods for handling the data. For this purpose a DICOM loader for IRIS Performer has been developed. The loader was designed for SGI machines as a shared object, which is executed at LIMBO's runtime. The loader loads not only the selected DICOM dataset, but also methods for rendering, handling, and interacting with the data, bringing networked, real-time, stereoscopic interaction with radiological data to reality. Collaborative, interactive methods currently implemented in the loader include cutting planes and windowing. The Tele-Immersive environment has been tested on the UIC campus over an ATM network. We tested the environment with 3 nodes; one ImmersaDesk at the VRMedLab, one CAVE at the Electronic Visualization Laboratory (EVL) on east campus, and a CT scan machine in UIC Hospital. CT data was pulled directly from the scan machine to the Tele-Immersion server in our Laboratory, and then the data was synchronously distributed by our Onyx2 Rack server to all the VR setups. Instead of permitting medical volume visualization at one VR device, by combining teleconferencing, tele-presence, and virtual reality, the Tele-Immersive environment will enable geographically distributed clinicians to intuitively interact with the same medical volumetric models, point, gesture, converse, and see each other. This environment will bring together clinicians at different geographic locations to participate in Tele-Immersive consultation and collaboration.
由于获取高分辨率三维患者图像已变得十分普遍,超过100MB且包含250多层切片的医学容积数据集(CT或MR)很常见。让这些特定于患者的数据能快速提供给不同地理位置的众多专家并供其使用,这很重要。基于网络的系统已被开发出来,用于在网络上以低分辨率提供医学数据的容积或表面渲染,但这些系统无法充分处理立体可视化或庞大的数据集。最先进的虚拟现实技术和高速网络使得为地理上分散的临床医生创建一个环境成为可能,以便他们能实时沉浸式地共享这些海量数据集。伊利诺伊大学芝加哥分校(UIC)的医学虚拟现实实验室(VRMedLab)已开发出一种面向对象的方法,可将医学容积数据即时导入远程沉浸式环境。这种网络化虚拟现实设置基于LIMBO,它是一个应用框架或模板,提供远程沉浸所需的基本功能。我们开发了一个模块化通用远程沉浸程序,该程序能自动将3D医学数据与处理数据的方法结合起来。为此,已开发出用于IRIS Performer的DICOM加载器。该加载器被设计为SGI机器的共享对象,在LIMBO运行时执行。该加载器不仅能加载选定的DICOM数据集,还能加载用于渲染、处理和与数据交互的方法,将与放射学数据的网络化、实时、立体交互变为现实。加载器目前实现的协作式交互方法包括切割平面和开窗。远程沉浸式环境已在UIC校园通过ATM网络进行了测试。我们用3个节点测试了该环境:一个在VRMedLab的沉浸式桌面,一个在东校区电子可视化实验室(EVL)的CAVE,以及UIC医院的一台CT扫描仪。CT数据直接从扫描仪拉到我们实验室的远程沉浸服务器,然后由我们的Onyx2机架服务器将数据同步分发到所有虚拟现实设置中。通过结合电话会议、远程呈现和虚拟现实,远程沉浸式环境将使地理上分散的临床医生能够直观地与相同的医学容积模型进行交互、指点、做手势、交谈并相互看到,而不是只允许在一个虚拟现实设备上进行医学容积可视化。这个环境将汇聚不同地理位置的临床医生,参与远程沉浸式会诊与协作。