Jones Pete R, Somoskeöy Tamás, Chow-Wing-Bom Hugo, Crabb David P
1Division of Optometry and Visual Science, School of Health Science, Northampton Square, City, University of London, London, EC1V 0HB UK.
2Institute of Ophthalmology, University College London (UCL), 11-43 Bath Street, London, EC1V 9EL UK.
NPJ Digit Med. 2020 Mar 10;3:32. doi: 10.1038/s41746-020-0242-6. eCollection 2020.
Simulations of visual impairment are used to educate and inform the public. However, evidence regarding their accuracy remains lacking. Here we evaluated the effectiveness of modern digital technologies to simulate the everyday difficulties caused by glaucoma. 23 normally sighted adults performed two everyday tasks that glaucoma patients often report difficulties with: a visual search task in which participants attempted to locate a mobile phone in virtual domestic environments (virtual reality (VR)), and a visual mobility task in which participants navigated a physical, room-scale environment, while impairments were overlaid using augmented reality (AR). On some trials, a gaze-contingent simulated scotoma-generated using perimetric data from a real patient with advanced glaucoma-was presented in either the superior or inferior hemifield. The main outcome measure was task completion time. Eye and head movements were also tracked and used to assess individual differences in looking behaviors. The results showed that the simulated impairments substantially impaired performance in both the VR (visual search) and AR (visual mobility) tasks (both < 0.001). Furthermore, and in line with previous patient data: impairments were greatest when the simulated Visual Field Loss (VFL) was inferior versus superior ( < 0.001), participants made more eye and head movements in the inferior VFL condition ( < 0.001), and participants rated the inferior VFL condition as more difficult ( < 0.001). Notably, the difference in performance between the inferior and superior conditions was almost as great as the difference between a superior VFL and no impairment at all (VR: 71%; AR: 70%). We conclude that modern digital simulators are able to replicate and objectively quantify some of the key everyday difficulties associated with visual impairments. Advantages, limitations, and possible applications of current technologies are discussed. Instructions are also given for how to freely obtain the software described (OpenVisSim).
视觉障碍模拟用于教育公众并向其提供信息。然而,关于其准确性的证据仍然不足。在此,我们评估了现代数字技术模拟青光眼所致日常困难的有效性。23名视力正常的成年人完成了两项青光眼患者常称有困难的日常任务:一项视觉搜索任务,参与者试图在虚拟家庭环境(虚拟现实(VR))中找到一部手机;另一项视觉移动任务,参与者在物理的房间规模环境中导航,同时使用增强现实(AR)叠加损伤。在一些试验中,使用来自一名晚期青光眼真实患者的视野数据生成的注视相关模拟暗点,呈现在上半视野或下半视野。主要结局指标是任务完成时间。还跟踪了眼睛和头部运动,并用于评估注视行为的个体差异。结果表明,模拟损伤在VR(视觉搜索)和AR(视觉移动)任务中均显著损害了表现(两者均P<0.001)。此外,与先前的患者数据一致:当模拟视野缺损(VFL)在下半视野而非上半视野时,损伤最大(P<0.001),参与者在VFL在下半视野的情况下进行了更多的眼睛和头部运动(P<0.001),并且参与者将VFL在下半视野的情况评为更困难(P<0.001)。值得注意的是,下半视野和上半视野情况之间的表现差异几乎与上半视野VFL和无损伤之间的差异一样大(VR:71%;AR:70%)。我们得出结论,现代数字模拟器能够复制并客观量化与视觉障碍相关的一些关键日常困难。讨论了当前技术的优点、局限性和可能的应用。还给出了如何免费获取所描述软件(OpenVisSim)的说明。