3D Printed Smartphone Indirect Lens Adapter for Rapid, High Quality Retinal Imaging

Obtaining a secure, photographic record of clinical findings during patient encounters can serve as a powerful adjunct to the otherwise text-heavy documentation that dominates modern electronic health record systems. This is particularly true in ophthalmology, which is one of several medical specialties that relies heavily on images for diagnosis and treatment. Conventionally, ophthalmic imaging has required expensive, tabletop units operated by a trained technician in an outpatient clinic setting. The ubiquity and evolution of smartphones into both high-resolution cameras and conduits for encrypted data transfer has the potential to change this; however, their use is inherently limited by the optics and lighting required to image the eye, and in particular, the retina. Here, we report the development of a lightweight, compact, user-friendly, 3D printed attachment enabling high quality fundus photos by coupling smartphones to indirect ophthalmoscopy condensing lenses. The attachment is designed to hold a specific lens at a prescribed but adjustable distance from the camera lens, can utilize either the phone’s native flash for lighting or another coaxial light source, and has the potential to be operated with one hand. Using both mechanical prototypes and subsequent 3D printed versions of the device, we were able to photodocument a variety of both normal and abnormal retinal findings.