Soliz Peter, Nemeth Sheila C, Barriga E Simon, Harding Simon P, Lewallen Susan, Taylor Terrie E, MacCormick Ian J, Joshi Vinayak S
VisionQuest i-Rx Corporation, Albuquerque, NM, 87106-4358, USA.
Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, UK.
Proc SPIE Int Soc Opt Eng. 2016 Feb;9693. doi: 10.1117/12.2213282. Epub 2016 Mar 4.
The purpose of this study was to test the suitability of three available camera technologies (desktop, portable, and i-phone based) for imaging comatose children who presented with clinical symptoms of malaria. Ultimately, the results of the project would form the basis for a design of a future camera to screen for malaria retinopathy (MR) in a resource challenged environment. The desktop, portable, and i-phone based cameras were represented by the Topcon, Pictor Plus, and Peek cameras, respectively. These cameras were tested on N=23 children presenting with symptoms of cerebral malaria (CM) at a malaria clinic, Queen Elizabeth Teaching Hospital in Malawi, Africa. Each patient was dilated for binocular indirect ophthalmoscopy (BIO) exam by an ophthalmologist followed by imaging with all three cameras. Each of the cases was graded according to an internationally established protocol and compared to the BIO as the clinical ground truth. The reader used three principal retinal lesions as markers for MR: hemorrhages, retinal whitening, and vessel discoloration. The study found that the mid-priced Pictor Plus hand-held camera performed considerably better than the lower price mobile phone-based camera, and slightly the higher priced table top camera. When comparing the readings of digital images against the clinical reference standard (BIO), the Pictor Plus camera had sensitivity and specificity for MR of 100% and 87%, respectively. This compares to a sensitivity and specificity of 87% and 75% for the i-phone based camera and 100% and 75% for the desktop camera. The drawback of all the cameras were their limited field of view which did not allow complete view of the periphery where vessel discoloration occurs most frequently. The consequence was that vessel discoloration was not addressed in this study. None of the cameras offered real-time image quality assessment to ensure high quality images to afford the best possible opportunity for reading by a remotely located specialist.
本研究的目的是测试三种现有摄像技术（台式、便携式和基于iPhone的）对呈现疟疾临床症状的昏迷儿童进行成像的适用性。最终，该项目的结果将为未来在资源有限环境中筛查疟疾视网膜病变（MR）的相机设计奠定基础。台式、便携式和基于iPhone的相机分别由拓普康、Pictor Plus和Peek相机代表。这些相机在非洲马拉维伊丽莎白女王教学医院的疟疾诊所对23名出现脑型疟疾（CM）症状的儿童进行了测试。每位患者由眼科医生散瞳后进行双眼间接检眼镜（BIO）检查，然后用这三种相机进行成像。每个病例均根据国际既定方案进行分级，并与作为临床金标准的BIO进行比较。观察者将三种主要的视网膜病变作为MR的标志物：出血、视网膜变白和血管变色。研究发现，中等价格的Pictor Plus手持式相机的表现明显优于价格较低的基于手机的相机，略优于价格较高的台式相机。将数字图像的读数与临床参考标准（BIO）进行比较时，Pictor Plus相机对MR的灵敏度和特异性分别为100%和87%。相比之下，基于iPhone的相机的灵敏度和特异性分别为87%和75%，台式相机为100%和75%。所有相机的缺点是视野有限，无法完整观察血管变色最常发生的周边区域。结果是本研究未涉及血管变色问题。没有一台相机提供实时图像质量评估，以确保高质量图像，为远程专家阅读提供最佳机会。
