Glaucoma is a disease that results in bbnormally high fluid pressure inside the eye that can damage optic nerves. The disease affects more than 60 million people worldwide, according to U.K. firm Cambridge Consultants. The most common form of the disease is open-angle glaucoma, which accounts for 95 percent of the cases. Early detection of the disease is imperative because damage is irreversible and can lead to total blindness.

According to the firm, current testing technology works “exceptionally well,” but the system is overloaded and the testing devices are expensive. Cambridge Consultants has developed a smartphone glaucoma screening technology called Viewi designed to augment clinical tests. The test could be used in clinics for quick screening. People with a family history of open-angled glaucoma or with early signs of glaucoma could use the device at home to monitor the disease’s progression.

The Viewi system includes a smartphone app, a Bluetooth finger button, and a headset that holds smartphones. A patient slides the smartphone into the viewer, starts the app, puts the viewer on, and holds the button in one hand. The app runs a suprathreshold test, which records the limits or perimeter of the patient’s vision. When the patient sees a light flash she pushes the button. The test results are displayed in what the company calls an intuitive, nontechnical format on the smartphone. Results can also be transmitted to healthcare professionals.

According to Simon Karger, head of surgical and interventional products at Cambridge Consultants, “Loss of vision as a result of open-angle glaucoma cannot be recovered – but early diagnosis and treatment can slow the progression of the disease. But although the current clinical tests work exceptionally well, the system for glaucoma management is overloaded. We’ve used our optical expertise – coupled with our algorithm skills – to show how a simple, affordable, fast glaucoma screening test that patients can do at home is entirely feasible. The Viewi system doesn’t aim to replace the current screening and management system – it’s been designed to augment the clinical tests.”

Chris Dainty, a professor at University College London Institute of Ophthalmology and Moorfields Eye Hospital said, “The Viewi technology could provide a valuable early warning system for people at risk of developing glaucoma, as well as patients who need to monitor the effects of the disease on their vision. It could also make the static perimetry test accessible to more patients in developing countries, where expensive clinical equipment and trained professionals are often in short supply.”