Sixty million people in both developed and developing countries are affected by a group of eye diseases called Glaucoma globally . According to a study by a non government organisation, Sightsavers, one of only nine aid organisations to receive an overall high performance rating from the UK Government’s Partnership Performance Arrangement, Glaucoma is the third biggest cause of blindness worldwide and if it could be diagnosed earlier it can be prevented, but as it develops gradually, people remain unaware about it, reports BSS. In Asia, where eye tests are not as common, checking for glaucoma is more difficult, and is not likely to get picked up until it reaches a stage where it is much harder to treat, the study added. "According to a survey conducted during 1997 to 1998 in Dhaka, at least 2.8 percent people are affected by Glaucoma, while 90 percent of people do not know about the disease", Secretary General of Bangladesh Glaucoma Society (BGS) Dr Nazneen Khan told BSS. Highlighting the necessity of early detection, the eye expert, also an Associate Professor of Ophthalmology Department of Bangabandhu Sheikh Mujib Medical University (BSMMU) Dr Sharfuddin Ahmad said, "Medications, treatments, technology and research can help the patients afflicted with glaucoma but early detection is the first and most important step to protect the eyes". Glaucoma is a group of eye diseases that causes progressive damage to the optic nerve at the point where it leaves the eye to carry visual information to the brain. There are several variations of glaucoma, but primary open-angle is the most common. It occurs when fluid in the eye doesn't properly drain out and it can cause irreversible loss of vision and severe damage to the nerve fibers of the optic nerve. Bangladesh is also observing The World Glaucoma Week countrywide like other countries in the world from March 8 to 14 for raising awareness about glaucoma with the slogan "Beat Invisible Glaucoma". To mark the last day of the Week BGS will organize a free Glaucoma screening camp at Harun Eye Foundation Hospital from 9:30am to 11:30am on Saturday at city's Dhanmondi area. A human chain will also be organised to mark the Day at the same place. This week was established by the World Glaucoma Association and the World Glaucoma Patients Association to create awareness among people regarding the disease.