Glaucoma is usually the result of increased pressure in the eye, resulting in damage to the optic nerve, which carries information to the brain. Since the symptoms of glaucoma do not show up until very late stages, early detection by a procedure called fundus imaging is advised.
Fundus imaging involves taking photographs of the retina and neurosensory tissue for analysis. This can be tedious and requires special equipment handled by skilled technicians to measure the cup-to-disc ratio which compares the diameter of the "cup" portion of the optic disc with the diameter of the full optic disc.
Software developed at the IISc greatly simplifies the procedure by using software to rapidly analyse images which can be taken with a handheld fundus camera or even with a smartphone camera.
“We calculate parameters like cup-to-disc ratio to identify potentially glaucomatous conditions,” says Chandra Sekhar Seelamantula, professor of electrical engineering at the IISc and leader of the team that developed the new method. “This pre-screening tool can detect glaucoma with 90 per cent accuracy,” he tells SciDev.Net.
Seelamantula says mass screening of fundus images by semi-skilled people is possible with pre-screening software. ”The software allows rapid screening of the images and highlights those that need the attention of the specialist. This is useful when hospitals, government healthcare units or NGOs conduct healthcare camps,” he says.
The IISc team has not, so far, patented the technology but there is interest in making it suitable for mass application by converting the Java-based software into an Android app for example, says Seelamantula. Companies ranging from start-ups to large corporations have been making enquiries, he says.
Sudipto Pakrasi, chairman of the ophthalmology division at Medanta,Gurgaon, Haryana, tells SciDev.Net that currently available technologies for detection of glaucoma are expensive while the new method is not only cheap, but will also help with mass-screening for glaucoma. About 12 per cent of India’s 1.2 billion people is estimated to be affected by glaucoma.
“Damage to the optic nerve due to glaucoma is not reversible. If we detect it early then it is possible to halt the progression of glaucoma by appropriate medications or surgery,” Pakrasi says. ”Vision may be preserved at nearly normal levels if glaucoma is detected and treated early.”
This article has been produced by SciDev.Net's South Asia desk.