DIY nonmydriatic fundus camera

An ophthalmology resident at the University of Illinois at Chicago College of Medicine has invented an inexpensive, handheld camera that can photograph the retina without need for pupil dilation.

Dr. Bailey Shen’s design is so simple he includes a shopping list of necessary parts and instructions for assembly in his paper published in Journal of Ophthalmology. He says the camera can be replicated from parts easily found online for about $185.

“The device is currently just a prototype, but it shows that it is possible to build a cheap camera capable of taking quality pictures of the retina without dilating eye drops,” Shen said. “It would be cool someday if this device or something similar was carried around in the white-coat pockets of every ophthalmology resident and used by physicians outside of ophthalmology as well.”

Dr. Shen’s prototype utilizes a Raspberry Pi 2 computer, a cheap single-board miniature computer, combined with a dual infrared and white light diode and an infrared camera. The device can take a photo through an undilated pupil because it uses infrared light, which does not trigger a pupillary response. The diode then emits a quick flash of white light as the picture is taken. Dual-light cameras with similar function are already available, but they are large and cost thousands of dollars.

“This is an open-source device that is cheap and easy to build,” said Shizuo Mukai, associate professor of ophthalmology at Harvard Medical School and the paper’s co-author. “We expect that others who build our camera will add their own improvements and innovations.”

Dr. Shen was inspired to create the device to fill an unmet need shared by many physicians.

“As residents seeing patients in the hospital, there are often times when we are not allowed to dilate patients — neurosurgery patients for example. Also, there are times when we find something abnormal in the back of the eye, but it is not practical to wheel the patient all the way over to the outpatient eye clinic just for a photograph.”

Dr. Bailey Shen has a fundus photograph taken with his portable camera