ARTICLE Global Teleophthalmology With iPhones for Real-Time Slitlamp Eye Examination Yufeng Ye, M.D., Ph.D., Jianhua Wang, M.D., Ph.D., Yanan Xie, M.D., Jianguang Zhong, M.D., Yongpin Hu, M.D., Bin Chen, M.D., Xiaojian He, M.D., and Huicheng Zhang, M.D., Ph.D. Purpose: To evaluate the image resolutions in global teleophthalmology using 2 smartphones. Methods: A standard resolution test card and two human eyes (one eye wearing a contact lens) were imaged with an iPhone 4S adapted for slitlamp biomicroscopy in Hangzhou, Zhejiang, China. An iPhone 5 was used as a receptor on the other side of the world (Miami, FL). The real-time images and still images were transferred through Skype from Hangzhou to Miami during slitlamp eye examination. The real-time resolutions captured and displayed on the both phones at different places were measured. There was vocal communication concurrent between two parties during image transference and the examination by the slitlamp biomicroscopy performed in Hangzhou. Results: The real-time and still images were transferred between two cities while two operators talked with each other smoothly and without difficulty. The viewer in Miami was able to instruct the operator in Hangzhou to thoroughly examine the eye using the slitlamp microscopy with different magnification settings and illumination settings. The resolution of the still images recorded in the iPhone in Hangzhou was higher than that of the real-time images on the screen. The main features of the eye were recognizable in real-time. Conclusions: The study demonstrated that global teleophthalmology is feasible using two smartphones. The system is simple, portable, and affordable, and the image quality in still and real-time images is acceptable for real-time teleophthalmology. Key Words: Telemedicine—Ophthalmology—Smartphone. (Eye & Contact Lens 2014;40: 297–300) T eleophthalmology has become a useful tool in the diagnosis and formulation of treatment plans for diseases such as glau- coma, 1 cataracts, 2–4 trachoma, 5 and diabetic retinopathy, among others. 6 The technology offers several advantages over conven- tional consultations, including cost-effectiveness and service acces- sibility in remote areas. A teleophthalmology system requires a series of pieces of equipment, such as a webcam, slitlamp pho- tography system, and data exchange device. 2 These requirements may be a burden for remote or developing areas where telemedi- cine is needed. Smartphones are displaying growing utility in the field of ophthalmology. In the United States, it was estimated that approximately 81% of physicians had smart phones in 2012. 7 There are many studies that have used smartphones for teleoph- thalmology. 7–10 Using smartphones is convenient and can alleviate the need to carry bulky equipment to a remote site. The wireless connection of the smartphones adds another advantage by provid- ing easy Internet connection, which is a must for teleophthalmol- ogy. The iPhone can record high-quality images of the eye through slitlamp microscopy. 11 The goal of this study was to evaluate the image resolution for global teleophthalmology using slitlamp eye examination settings between two iPhone devices. METHODS An iPhone 4S (Apple, Cupertino, CA) was adapted to a Haag- Streit BQ-900 slitlamp (Haag-Streit, Gartenstadtstrasse, Switzerland) located in the Department of Ophthalmology, Hangzhou First People’s Hospital, Hangzhou, China. Similar to the approach re- ported in our previous study, 11 a beam splitter (50:50) was mounted on the BQ-900 slitlamp (Fig. 1). The iPhone 4S was connected with a relay lens (+60-D Volk lens) and a magnification lens (a +8-D lens). The iPhone 4S device was attached to a plate (CP4S; Thorlabs, Newton, NJ) and secured with the relay lens. The relay lens and magnification lens were adjusted for fine focusing through the sli- tlamp. An iPhone utility (SimpleCam, from the Apple store) was used to lock the focal plane during imaging. The focal plane of the iPhone camera was adjusted to be at the same plane as the slitlamp microscope to facilitate the focusing process. An iPhone 5 in Miami was connected to the Internet. The communication between these phones was set up through the Skype (Skype Communication SARL, Luxembourg, Grand Duchy of Luxembourg) online chatting service through wireless connections. A resolution test card (USAF 1951; Edmund Optics, Inc, Barrington, NJ) was observed and imaged for measuring the real- time display and image resolutions. The spatial resolution was defined as the closest lines of the resolution test card that could be resolved in an image. The practical clarity of the image was decided by the spatial resolution. In this study, the real-time spatial resolution was defined as the resolution test card readable on the iPhone 4S screen. The real-time display of the iPhone 4S in Hangzhou was observed on the screen. The image spatial resolution was defined as the still image spatial resolution readable to the observer on the touch screen when the resolution test card was imaged. The same observers (Y.Y. in Hangzhou and J.W. in Miami) conducted all of the mea- surements. The real-time resolution and still image spatial resolution on both iPhones touch screens were recorded. The left eye of a healthy subject was imaged. The real-time images and still images From the Department of Opthalmology (Y.Y., J.Z., Y.H., B.C., X.H., H.Z.) Hangzhou First People’s Hospital, Hangzhou, China; Bascom Palmer Eye Institute (J.W.), University of Miami, Miami, FL; and Hangzhou Normal University (Y.X.), Hangzhou, China. The authors have no funding or conflicts of interest to disclose. Address correspondence to Huicheng Zhang, M.D., Ph.D., Department of Opthalmology, Hangzhou First People Hospital, 261 Huansha Road, Hangzhou, Zhejiang, 310006, China; e-mail: zhczhl@163.com Accepted May 9, 2014. DOI: 10.1097/ICL.0000000000000051 Eye & Contact Lens  Volume 40, Number 5, September 2014 297 Copyright @ Contact Lens Association of Opthalmologists, Inc. Unauthorized reproduction of this article is prohibited.