Glaucoma is a condition in which there is damage to the optic nerve that carries light impulses to the brain, allowing us to see. This may be associated with increased pressure within the eye or even with normal pressure.
Glaucoma is of public health importance globally because it is the third leading cause of blindness, after cataract and uncorrected refractive error. In India, there are an estimated 1.1 crore people living with glaucoma. The prevalence of glaucoma increases with age. The burden of the disease and therefore also of visual impairment and blindness tends to increase with age. According to the Central India Eye and Medical Study, the prevalence of glaucoma was found to be 3.45 per cent over the age of 40, 5.11 per cent over the age of 50 and 7.50 per cent over the age of 60. With increasing life expectancy, we expect the number of people with glaucoma and glaucoma-related blindness to increase in India.
One of the great challenges is the lack of diagnosis—not more than 10 per cent of patients have been diagnosed with glaucoma. The vast majority remains undiagnosed, unaware and untreated. Based on demographics, we can assume that 70 per cent of patients live in rural areas, where lack of accessibility to proper care results in a very small percentage of patients being diagnosed and treated on time.
There are two main types of glaucoma—primary open-angle glaucoma and primary angle-closure glaucoma. The first one is characterised by a silent, slow course and by typical changes in the optic disc affecting the visual fields. It is asymptomatic, so the patient may not know that he/she has glaucoma. Therefore, it is important that all patients over 40 years have regular eye examinations. Primary angle-closure glaucoma is characterised by significantly elevated intraocular pressure and, if undetected and untreated, can lead to rapid loss of vision.
The diagnosis of glaucoma has improved a great deal because of modern clinical skills and instruments. This means that once a patient consults an ophthalmologist, there is a high possibility that the disease is detected at a very early stage, which helps in early initiation of treatment and a slowing down of the disease’s progress.
Glaucoma may be treated using prescribed eye drops. There are several options available to help lower intraocular pressure. Many of these medications can be used in combination, so specialists may recommend up to three eye drops to enable more efficient lowering of intraocular pressure to the desired level. Some of the drops need to be used only once a day and others twice a day. It is of utmost importance to use the drops regularly. Most of the drops are now manufactured in India and are easily available. The challenge sometimes is affordability, but this should get better as public health care facilities start providing these medicines at a more affordable price.
Laser treatment can also help to treat glaucoma and lower eye pressure. It can be used for both types of glaucoma. Glaucoma surgery is commonly done for patients in whom the eye pressure cannot be lowered by drops. The introduction of newer surgical implant devices has also enabled better control of intraocular pressure.
Affordability and accessibility are the key barriers to glaucoma care. Even as we talk about creating affordable health care solutions in technology, medicine and health care infrastructure and delivery, there are significant challenges to achieve this. Expensive technology enables early detection of glaucoma. Less expensive technology is used to detect moderate to severe glaucoma. Government initiatives in providing medications at lower price points is a significant enabler. Surgical therapy continues to be a major area which needs to be tackled.
The writer is chairman, Suraj Eye Institute, Nagpur.
INDIA & GLAUCOMA
* As India continues to deal successfully with curable causes of blindness, glaucoma can become the most important cause of blindness by the end of this century.
* Increasing life expectancy is one reason why more people are being diagnosed with glaucoma.
* Newer technology helps in early diagnosis of glaucoma, but it is very expensive and often out of reach.
* Accessing the community, just as we are doing for diabetes detection in India, can lead to significantly increased diagnosis of glaucoma, especially in the rural communities.
* District hospitals and peripheral centres need to be able to do basic glaucoma examination, diagnosis and provide treatment including surgery.