Department of Electrical and Computer Engineering, Worcester Polytechnic Institute, Worcester, Massachusetts 01609, USA.
Telemed J E Health. 2010 Mar;16(2):161-6. doi: 10.1089/tmj.2009.0103.
This work evaluates the feasibility of using 802.11 g ad hoc and 3G cellular broadband networks to wirelessly stream ultrasound video in real-time. Telemedicine ultrasound applications in events such as disaster relief and first-response triage can incorporate these technologies, enabling onsite medical personnel to receive assistance with diagnostic decisions by remote medical experts. The H.264 scalable video codec was used to encode echocardiographic video streams at various image resolutions (video graphics array [VGA] and quarter video graphics array [QVGA]) and frame rates (10, 15, 20, and 30 frames/s). The video stream was transmitted using 802.11 g and 3G cellular technologies, and pertinent transmission parameters such as data rate, packet loss, delay jitter, and latency were measured. 802.11 g permits high frame rate and VGA resolution and has low latency and jitter, but it is suitable only for short communication ranges, whereas the 3G cellular network allows medium to low frame rate streaming at QVGA image resolution with medium latency. However, video streaming can take place from any location with 3G service to any other site with Internet connectivity. The transmitted ultrasound video streams were subsequently recorded and evaluated by physicians with expertise in medical ultrasonography who evaluated the diagnostic value of the received video streams relative to the original videos. They expressed the opinion that image quality in the case of both 802.11 g and 3G was fully to adequately preserved, but missed frames could momentarily decrease the diagnostic value. This research demonstrates that 3G and 802.11 g wireless networks combined with efficient video compression make diagnostically valuable wireless streaming of ultrasound video feasible.
这项工作评估了使用 802.11g 自组织网络和 3G 蜂窝宽带网络实时无线传输超声视频的可行性。远程医疗超声应用在灾难救援和第一响应分诊等事件中，可以采用这些技术，使现场医务人员能够通过远程医疗专家获得诊断决策的协助。使用 H.264 可扩展视频编解码器，以各种图像分辨率（视频图形阵列[VGA]和四分之一视频图形阵列[QVGA]）和帧率（10、15、20 和 30 帧/秒）对超声视频流进行编码。使用 802.11g 和 3G 蜂窝技术传输视频流，并测量相关传输参数，如数据速率、丢包率、延迟抖动和延迟。802.11g 允许高帧率和 VGA 分辨率，具有低延迟和抖动，但仅适用于短距离通信，而 3G 蜂窝网络允许在 QVGA 图像分辨率下以中等至低帧率进行流媒体传输，具有中等延迟。然而，视频流可以从任何具有 3G 服务的位置传输到任何具有互联网连接的其他位置。随后，具有医学超声专业知识的医生对传输的超声视频流进行记录和评估，他们评估了接收的视频流相对于原始视频的诊断价值。他们认为，802.11g 和 3G 的图像质量都得到了充分的保留，但丢失的帧可能会暂时降低诊断价值。这项研究表明，3G 和 802.11g 无线网络与高效视频压缩相结合，可以实现具有诊断价值的超声视频无线流媒体传输。
