To evaluate the image resolutions in global teleophthalmology using 2 smartphones.
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.
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.
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.