Technical University of Munich, Garching bei München, Germany.
Translational Research Lab, Carl Zeiss Meditec, München, Germany.
Int J Comput Assist Radiol Surg. 2020 May;15(5):781-789. doi: 10.1007/s11548-020-02135-w. Epub 2020 Apr 2.
Intraoperative optical coherence tomography (iOCT) was recently introduced as a new modality for ophthalmic surgeries. It provides real-time cross-sectional information at a very high resolution. However, properly positioning the scan location during surgery is cumbersome and time-consuming, as a surgeon needs both his hands for surgery. The goal of the present study is to present a method to automatically position an iOCT scan on an anatomy of interest in the context of anterior segment surgeries.
First, a voice recognition algorithm using a context-free grammar is used to obtain the desired pose from the surgeon. Then, the limbus circle is detected in the microscope image and the iOCT scan is placed accordingly in the X-Y plane. Next, an iOCT sweep in Z direction is conducted and the scan is placed to centre the topmost structure. Finally, the position is fine-tuned using semantic segmentation and a rule-based system.
The logic to position the scan location on various anatomies was evaluated on ex vivo porcine eyes (10 eyes for corneal apex and 7 eyes for cornea, sclera and iris). The mean euclidean distances (± standard deviation) was 76.7 (± 59.2) pixels and 0.298 (± 0.229) mm. The mean execution time (± standard deviation) in seconds for the four anatomies was 15 (± 1.2). The scans have a size of 1024 by 1024 pixels. The method was implemented on a Carl Zeiss OPMI LUMERA 700 with RESCAN 700.
The present study introduces a method to fully automatically position an iOCT scanner. Providing the possibility of changing the OCT scan location via voice commands removes the burden of manual device manipulation from surgeons. This in turn allows them to keep their focus on the surgical task at hand and therefore increase the acceptance of iOCT in the operating room.
术中光学相干断层扫描（iOCT）最近被引入眼科手术，作为一种新的模态。它以非常高的分辨率提供实时的横截面信息。然而，在手术中正确定位扫描位置非常繁琐和耗时，因为外科医生需要双手进行手术。本研究的目的是提出一种在眼前节手术中自动定位感兴趣解剖结构的 iOCT 扫描的方法。
首先，使用上下文无关语法的语音识别算法从外科医生那里获得所需的姿势。然后，在显微镜图像中检测到角膜缘圆，并相应地在 X-Y 平面上放置 iOCT 扫描。接下来，在 Z 方向进行 iOCT 扫描，并将扫描放置在最顶层结构的中心。最后，使用语义分割和基于规则的系统进行精调。
在离体猪眼（角膜顶点 10 只眼，角膜、巩膜和虹膜 7 只眼）上评估了在各种解剖结构上定位扫描位置的逻辑。平均欧几里得距离（±标准差）为 76.7（±59.2）像素和 0.298（±0.229）毫米。四种解剖结构的平均执行时间（±标准差）为 15（±1.2）秒。扫描大小为 1024×1024 像素。该方法已在 Carl Zeiss OPMI LUMERA 700 上与 RESCAN 700 一起实现。
本研究介绍了一种完全自动定位 iOCT 扫描仪的方法。通过语音命令改变 OCT 扫描位置的可能性，减轻了外科医生手动操作设备的负担。这反过来又使他们能够将注意力集中在手头的手术任务上，从而提高 iOCT 在手术室中的接受程度。
