Glaucoma and Cataract

Both cataracts and glaucoma become more common with increasing age. Many people over 60 may have both.

• A cataract is an eye condition where cloudiness, or opacity in the lens (behind the iris), blocks or changes the entry of light, affecting vision.
• Glaucoma is a group of eye diseases that gradually steals sight without warning and often without symptoms. Vision loss is caused by damage to the optic nerve at the back of the eye.

Cataracts and glaucoma are both serious conditions that can cause you to lose vision. Loss of vision due to cataracts can be reversed with surgery. Loss of vision from glaucoma is irreversible.

Are those with glaucoma at higher risk of developing cataracts?

Those with glaucoma are usually not at higher risk of developing cataracts. There are exceptions, including those who have glaucoma due to secondary causes such as eye inflammation, eye trauma, or steroid medication use. Also at higher risk are those with developmental conditions, such as congenital rubella which can cause glaucoma and cataract, or sometimes both. Both eye conditions are also more common with age, which is why many who have one disease may develop the other.

Can surgery restore vision loss from a cataract?

Unlike vision loss from glaucoma, cataract-associated vision loss can often be regained. In cataract surgery, the cloudy lens of the eye is removed and replaced with a clear plastic lens called an intraocular lens implant. The natural lens is surrounded by a capsule that holds it in place.

During cataract surgery, an opening is created in the front part of the capsule so the surgeon can remove the lens, but the back layer of the capsule, known as the posterior capsule, is left intact to help stabilize the lens.

In some patients, after a period of time following the cataract surgery, the posterior capsule can slowly thicken and cloud vision. A laser procedure called a capsulotomy can open this membrane, restoring vision without surgery.

When is cataract surgery needed?

Cataract surgery is suggested when a person’s vision has declined to the point where it interferes with their usual daily tasks.

How will cataract surgery affect glaucoma?

Cataract surgery can cause a change in eye pressure. This change may be short-term or permanent. In general, it is not possible to predict whether the eye pressure will rise, fall or stay the same after cataract surgery. However, most people have slightly lower eye pressure following cataract surgery. This is often not permanent and the pressure may increase again after the surgery.

Sharp increases in eye pressure immediately after the surgery are called ‘pressure spikes’ and sometimes occur in patients 1-2 days after cataract surgery. Often these pressure spikes are short-term and can be treated with medication. Sometimes your doctor may give you a tablet or some eye drops to use following surgery to prevent these pressure spikes.

If both glaucoma surgery and cataract surgery are needed, can the two procedures be combined?

The first priority is to control glaucoma. A person may have a glaucoma procedure followed by cataract surgery or have both surgeries done at the same time. The specific approach will depend on the medical needs of the person with glaucoma.

Is there a need to change glaucoma medication after cataract surgery?

In many patients after cataract surgery, your doctor may reassess the glaucoma drops that are prescribed. In some instances, glaucoma drops can be decreased, while other times, there may be the need for more intensive glaucoma treatment. This should be discussed with your doctor.