Miladinović Aleksandar, Quaia Christian, Kresevic Simone, Ajčević Miloš, Diplotti Laura, Michieletto Paola, Accardo Agostino, Pensiero Stefano
Institute for Maternal and Child Health-IRCCS, Trieste, 34100, Italy, 39 0405587124.
Laboratory of Sensorimotor Research, National Eye Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD, United States.
JMIR Pediatr Parent. 2024 Dec 9;7:e64353. doi: 10.2196/64353.
Ocular following responses (OFRs)-small-amplitude, short-latency reflexive eye movements-have been used to study visual motion processing, with potential diagnostic applications. However, they are difficult to record with commercial, video-based eye trackers, especially in children.
We aimed to design and develop a noninvasive eye tracker specialized for measuring OFRs, trading off lower temporal resolution and a smaller range for higher spatial resolution.
We developed a high-resolution eye-tracking system based on a high-resolution camera operating in the near-infrared spectral range, coupled with infrared illuminators and a dedicated postprocessing pipeline, optimized to measure OFRs in children. To assess its performance, we: (1) evaluated our algorithm for compensating small head movements in both artificial and real-world settings, (2) compared OFRs measured simultaneously by our system and a reference scleral search coil eye-tracking system, and (3) tested the system's ability to measure OFRs in a clinical setting with children.
The simultaneous measurement by our system and a reference system showed that our system achieved an in vivo resolution of approximately 0.06°, which is sufficient for recording OFRs. Head motion compensation was successfully tested, showing a displacement error of less than 5 μm. Finally, robust OFRs were detected in 16 children during recording sessions lasting less than 5 minutes.
Our high-resolution, noninvasive eye-tracking system successfully detected OFRs with minimal need for subject cooperation. The system effectively addresses the limits of other OFR measurement methods and offers a versatile solution suitable for clinical applications, particularly in children, where eye tracking is more challenging. The system could potentially be suitable for diagnostic applications, particularly in pediatric populations where early detection of visual disorders like stereodeficiencies is critical.
眼球跟踪反应（OFRs）——小幅度、短潜伏期的反射性眼球运动——已被用于研究视觉运动处理，并具有潜在的诊断应用价值。然而，使用商用的基于视频的眼动仪很难记录到它们，尤其是在儿童中。
我们旨在设计并开发一种专门用于测量OFRs的非侵入性眼动仪，以较低的时间分辨率和较小的范围为代价来换取更高的空间分辨率。
我们基于一台在近红外光谱范围内工作的高分辨率相机，开发了一种高分辨率眼动跟踪系统，并结合红外照明器和一个专用的后处理管道，对其进行了优化，以测量儿童的OFRs。为了评估其性能，我们：（1）在人工和现实环境中评估了我们用于补偿小幅度头部运动的算法，（2）比较了我们的系统和一个参考巩膜搜索线圈眼动跟踪系统同时测量的OFRs，以及（3）在临床环境中测试了该系统测量儿童OFRs的能力。
我们的系统与参考系统的同步测量表明，我们的系统在体内实现了约0.06°的分辨率，这足以记录OFRs。头部运动补偿测试成功，显示位移误差小于5μm。最后，在持续时间不到5分钟的记录过程中，在16名儿童中检测到了稳定的OFRs。
我们的高分辨率、非侵入性眼动跟踪系统成功地检测到了OFRs，对受试者合作的需求最小。该系统有效地解决了其他OFR测量方法的局限性，并提供了一种适用于临床应用的通用解决方案，特别是在儿童中，眼动跟踪更具挑战性。该系统可能适用于诊断应用，特别是在儿科人群中，早期发现立体视缺陷等视觉障碍至关重要。
