Glaucoma is one of those things that can creep up on you quietly, gradually destroying your sight before you even know it. Nicknamed the “silent thief of sight,” glaucoma is a collection of eye diseases that damage the optic nerve, the critical link between your eyes and your brain. When this nerve is injured, the loss of vision is typically permanent, and in others, it causes blindness. What is particularly problematic is that people generally don’t realize something is amiss until damage is extensive.
So, what occurs within the eye? Glaucoma is most typically associated with elevated pressure within the eye, referred to as intraocular pressure (IOP). Your eyes constantly secrete a clear liquid called aqueous humor, which runs in and out to contribute to keeping the appropriate pressure. However, if the drainage system becomes slower or clogged, fluid accumulates and pressure increases. Eventually, this can harm the optic nerve. Nevertheless, not every person with elevated eye pressure develops glaucoma, and a few people with normal pressure nonetheless develop it. So, although pressure is a big contributor, it’s not the whole story.
There are no more than a handful of various types of glaucoma, and each of them works differently to some extent. The most common one is open-angle glaucoma. It develops gradually and without pain, making it especially hard to diagnose at an early stage. You will not notice anything until your side vision begins to deteriorate. The disease is established quite well when your central vision is affected. A second form, angle-closure glaucoma, is less common but more dramatic. It may attack suddenly, accompanied by eye pain, headache, nausea, foggy vision, or seeing halos around lights. This is a medical emergency and should be treated promptly. And then there’s normal-tension glaucoma, where optic nerve damage occurs even though eye pressure is normal, and congenital glaucoma, which appears in infants or toddlers due to problems with eye structure.
Certain people are also more prone to glaucoma. Age is one of them—people over 60 years old are more likely to develop it, and the risk increases with each decade. Genetics come into play as well; if a family member or a parent has glaucoma, your risk increases. Certain populations are also at risk, notably African American and Hispanic people, who tend to get the disease sooner and with greater aggressiveness. Other risks are diabetes, high blood pressure, heart conditions, a history of eye injuries or surgery, and even having thinner-than-usual corneas.
What makes glaucoma so difficult is that it usually doesn’t produce symptoms during the early phases. That’s why it is critical to have regular eye exams. The Centers for Disease Control and Prevention estimates that roughly half of those who have glaucoma don’t even realize it. A full eye exam is easy and painless, but it can be a game-changer. During the appointment, your eye doctor will measure your eye pressure (tonometry), examine your optic nerve (ophthalmoscopy), assess your side vision (perimetry), and evaluate the drainage angle inside your eye (gonioscopy). They might also measure your corneal thickness (pachymetry), which can influence both your risk factor and how your pressure is calculated.
Although there is no cure for glaucoma, it can be successfully treated and vision protected. The most common first treatment is prescription eye drops that either improve drainage from your eye or lower the amount of fluid your eye makes. Oral medication is taken by some individuals as well. Laser surgery enhances drainage or lessens fluid production in other instances. In more serious situations, surgery may be required to establish new drainage channels or unclog blocked vessels. There are even newer, more minimally invasive forms of surgery that have shorter recovery times and fewer side effects.
The secret to safeguarding your vision is being proactive. If you’re more than 40, it’s well worth having a full eye exam every two years—and more frequently if you have risk factors. Managing your blood pressure, cholesterol, and blood sugar levels, not smoking, and adhering to your doctor’s instructions if you develop glaucoma can all assist with maintaining your vision.
Glaucoma can be sneaky, but with proper information and constant care, you can prevent it from stealing your eyesight.