Glaucoma: Understanding the causes and symptoms of rising blindness cases

Glaucoma is the growing causes of blindness among individuals above the age of 60. Experts reveal the symptoms of this condition and what is causing it

Low brain pressure may increase the chance of developing glaucoma where one type of glaucoma is a condition caused by pressure inside the eye, also known as elevated intraocular pressure (IOP) - one of the main causes of blindness - and it is commonly diagnosed among individuals above the age of 60. Glaucoma is a progressive optic nerve head neuropathy and accounts for the third leading cause of blindness, following uncorrected refractive errors and cataracts but can be prevented or stabilised with early detection and treatment.

Treatment of glaucoma is much more successful when it is begun in early stages of the disease, when sight loss is minimal. (Shutterstock)

The worldwide glaucoma prevalence in 2020 between 40 and 80 years was estimated at 76 million, with India being projected to account for 20% of the global load. In 2010, numerous population based studies estimated a pooled prevalence of glaucoma in India to be around 11.2 million in individuals aged 40 years and above while the studies reported that glaucoma was nearly twice as prevalent in urban populations than rural populations.

In an interview with HT Lifestyle, Dr Sujal S Shah, Director and Consultant, Department-Ophthalmology at Sir HN Reliance Foundation Hospital, shared, “Risk factors for primary glaucoma include: increasing age, family history of glaucoma and increased intraocular pressure (IOP). While myopia (short-sightedness) is a risk factor for the open angle variant; hyperopia (long-sightedness), female sex and diabetes show a greater association with angle closure glaucoma. Secondary glaucoma usually results from various ocular or systemic disorders.”

Talking about the causes, he revealed, “In India, the estimated prevalence of secondary glaucomas vary between 0.1% to 21.8%. Numerous risk factors predispose towards secondary glaucoma such as: diabetes, hypertension, cardiac illness, previous eye trauma or surgery, advanced cataracts or even prolonged steroid use. More region specific population-based studies are needed to review the cost-effectiveness of tools used for education, screening, and diagnosis of glaucoma.”

Bringing his expertise to the same, Dr Santosh Bhide, Ophthalmologist and Eye Surgeon at Ruby Hall Clinic in Pune, explained, “The one which we call point, here it is called black water. It is a different disease from pearl point i.e. the white water that remains in the thick point, which we call cataract. The natural lens in our eye becomes pacified but in this vitreous point or glaucoma or black water disease, the nerve which remains in the back of the eye or the optic nerve, the layer at the back of the eye or the retina, the ganglia layer and the retinal fiber layer all get affected and due to this effect, the field of vision of our eye remains. That is, the huge field that we see through the eyes gradually decreases and the pressure of our eye, which we call rock pressure, also increases.”

He elaborated, “In some glaucoma cases, due to the increase in pressure in the back vein, our field of vision and ultimately vision is affected. One of the leading causes of blindness, glaucoma is the second-leading factor after cataracts. Unfortunately, there is a reason why some people are blind. Glaucoma is present. Numerous patients struggle to comprehend this. Without realising it, we observe the patient's posterior vein is constricted, his eye pressure has increased and his range of vision has been impacted when we perform his thorough examination. His cell layer has deteriorated. He arrives at such a level and does have a deficiency in the retainer fibre cell layer.”