Eye care professionals have called for prevention of age-related macular degeneration (AMD) of the eye, rather than its cure. They were participating in an interactive open seminar on ‘Photo Dynamic Therapy for AMD’ organised by the Rotary Club of Hyderabad at LV Prasad Eye Institute on Sunday. AMD is a vision problem that affects generally people above 60 years due to the gradual wearing out of one part of the eye, the macula. LVPEI has introduced a cutting-edge curative therapy called Photo Dynamic Therapy (PDT) to cure the disease. The Institute is well-equipped with digital angiographic and scanning laser ophthalmoscopic systems and a variety of retinal lasers for accurate and appropriate therapy.

Initiating the discussion, Dr G N Rao, Managing Director of LVPEI, said the percentage of AMD cases would go up with increase in life expectancy. By the year 2020, it was expected that about 20 % of the population would be above 60 years of age. Even at the present rate of 1.5 %, the number of people suffering from AMD would be several millions, he said.

Research was going on to identify the genetic reasons for this problem. Scientists were also working on nutrition and drugs. While retinal cell transplantation was being explored, it would take some time to bring out a retinal chip. Drugs that could prevent or slow down the progress of the disease, radiation therapy and gene therapies were also being studied, Dr Rao said.

He said LVPEI was focusing mainly on six fields, viz, to provide advanced tertiary care, to train all categories of eye-care personnel, to do research on problems relevant to the local population, to provide rehabilitation to the visually impaired, to participate in community initiative to meet the problems of eye-care and to engage itself in some product development that are essentially not available in India.

Dr Tara Prasad Dass, Director, Retinal Services and Clinical Research, LVPEI, who delivered the keynote address, said there were two forms of age-related macular degeneration, ‘wet’ and ‘dry’. About 80 to 90 % of the patients had the dry form, which involved thinning of the macular tissues and disturbances in its pigmentation. From 10 to 20 % of the patients had the wet form, which could involve leakage of serum and bleeding within and beneath the retina, opaque deposits, and eventually scar tissue. Dry AMD developed very slowly over a number of years with fading in the central areas of vision, while wet AMD progressed more rapidly and accounted for 90 % of all cases of blindness among AMD patients.

Dr Dass said PDT was the best therapy available to cure AMD. Although this therapy was costly (more than Rs 1 lakh), it was very effective. However, he said only the wet type of AMD could be treated with this approach. An early diagnosis was essential for the success of treatment. He said a vegetarian diet was the best option to keep this disease away. Daily supplements of anti-oxidants (vitamin C, E, beta carotene and zinc) could retard progress of AMD.

Though it was difficult to pinpoint the exact cause, like virtually every degenerative disease of the body, reactive molecules known as ‘free radicals’ were the likely root cause of AMD. Hereditary, dietary and lifestyle factors determined how well any individual was able to control these free radicals and where they would do the most damage. Diabetes, atherosclerosis and smoking might accelerate the process, Dr Dass said.

To a questioner, Dr Dass said AMD alone would not result in total blindness. Only the central (reading) vision was affected and the surrounding vision remained normal. In both types of macular degeneration, the useful side vision that allowed one to see to get around was retained.

Asked whether PDT could restore lost vision, Dr Dass said it would not restore vision lost to AMD, but it helped confine the retinal damage and slow down the progression of the disease.