To address the problem of blindness in poor rural areas, an organization called PeekVision is developing technology for eye testing using only a smartphone. The Portable Eye Examination Kit (PEEK) is an app that can be used with minimal training and is extremely low-cost and portable relative to conventional optometric equipment.
Blindness in Developing Countries
Of the 285 million people around the world with impaired vision, 39 million are blind. Eighty percent of blindness is avoidable through medical treatment and prevention, but these unnecessary sight losses occur anyway because 90 percent of people suffering from blindness live in poor countries. Treatment for common causes of blindness is often available even in the poorest countries, but only in major cities. The problem is getting the people most in need—who generally live far away from these cities with no easy means of transportation—diagnosed.
Eye Testing with a Smartphone
The PEEK app uses the phone’s camera to examine the lens of the eye. The phone’s light (designed for the camera flash) is used to illuminate the retina and examine it for diseases. The screen of the phone can show a shrinking letter to perform a basic visual acuity test. When all features are used, the app can diagnose refractive errors, cataracts, macular degeneration, glaucoma, diabetic retinopathy, and other, less common diseases of the retina and optic nerve.
Refractive errors such as myopia (nearsightedness), hyperopia (farsightedness), and astigmatism are common causes of impaired vision. Cataracts are a clouding of the lens of the eye, which is the most common cause of blindness and commonly occurs with age. In North America, more than 50 percent of people develop cataracts by age 80, but treatment is widely available. Macular degeneration is age-related retinal damage that impairs sight in the center of the visual field. Glaucoma is nerve damage to the eye, often resulting from increased fluid pressure inside the eye, which can lead to blindness if untreated. Diabetic retinopathy is damage to the blood vessels in the retina caused by diabetes and leading to blindness.
In addition to detecting these visual problems, the app can also screen for indicators of brain tumors and hemorrhage.
The Peek team is using their new app to perform eye testing on 5,000 people in rural Kenya. Simultaneously, a van loaded with expensive and fragile conventional eye examination materials is traveling the same land and testing the same people. This will allow Peek to determine how accurate their diagnoses are relative to diagnoses made with state-of-the-art equipment.
Applying the Technology
The app can be used by operators with minimal training, reserving the scarce resource of trained medical professionals for the treatments in which their expertise is really needed. The app saves eye testing data and links it to GPS coordinates. Ideally, the next step would be to help diagnosed patients travel to cities and gain access to subsidized eye care.
This technology could radically change eye care in the developing world. With extremely efficient eye testing, resources can be optimally directed to treat as many cases of preventable blindness as possible.