Abstract
Purpose :
Currently available binocular indirect ophthalmoscopes are large and expensive. We developed a compact and low-cost binocular indirect ophthalmoscope (BIO) using consumer 3D printing technology. Such a device may allow easier access to retinal examinations in low-resource settings.
Methods :
All 3D printed parts were designed using computer-aided design software and printed using a fused deposition model printer. The components were printed from acrylonitrile styrene acrylate, transparent polyethylene terephthalate, and thermoplastic polyurethane. The lighting and optical components were designed to comply with the International Organization for Standardization’s standards for BIOs. The illuminances of our 3D printed BIO as well as commercially available BIOs were tested with a light meter.
Results :
The 3D printed BIO resembles a commercially available spectacle-mounted BIO with the exception that the battery is contained within the body of the BIO. The total cost of the BIO is $208.60. It weighs 120 grams and is smaller than commercial BIOs such as the Keeler Iris Spectra. The BIO can be assembled with common tools in about 2-3 hours. The light system produces a collimated circular spotlight adjustable from 2 to 6.5 cm in diameter at 50 cm away. The intensity of the light can be controlled to a max intensity of 1300 lux with a run time of 7 hours. The BIO only produces visible light and does not produce any ultraviolet or infrared light. The indirect can be fully charged in under 4 hours via a USB-C port. The interpupillary distance ranges from 52 to 74 mm, and the BIO includes adjustment for stereopsis.
Conclusions :
We believe the optics and lighting of the 3D printed indirect are comparable to commercially available BIOs. Additionally, the 3D printed indirect is smaller and costs less than commercial spectacle-mounted BIOs, with the advantage of a wireless design that incorporates the battery into the frame itself. Replacement parts can be 3D printed or readily purchased online. These advantages make the BIO well-suited for both resource-rich and resource-limited settings. We believe our BIO is safe for patient care, and in the future, we plan to formally test our BIO using a spectroradiometer to ensure it meets optical radiation safety standards.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.