Cataract surgery and glaucoma – what is important to know before surgery

Cataract and glaucoma are two eye diseases that are common with age, and quite often they appear in the same person. People being treated for glaucoma whose vision starts to blur because of a cataract usually ask: Am I allowed to have cataract surgery? What will happen with my drops? And will the surgery affect the glaucoma? On this page we explain what is important to know before, during and after surgery.

What is the difference between cataract and glaucoma?

A cataract is a clouding of the eye's natural lens. It causes gradual blurring, and the vision lost because of it usually comes back after surgery in which the cloudy lens is removed and an artificial lens is implanted. More information is on the page What is a cataract.

Glaucoma is a disease that damages the optic nerve, most often in connection with eye pressure. Vision lost because of glaucoma does not come back, and the aim of treatment is to stop or slow the damage. So cataract surgery restores the vision that was lost because of the cloudy lens, but not the vision that was lost because of the glaucoma.

Can I have cataract surgery if I have glaucoma?

Yes. Glaucoma in itself does not rule out cataract surgery. In patients with another eye disease, the ophthalmologist needs to assess how much of the drop in vision comes from the cataract and how much from the other disease. This assessment is important for knowing what to expect from surgery: if most of the damage to vision comes from the cataract, the improvement is expected to be clearer. If the glaucoma is advanced, the improvement may be limited. Information on timing is on the page When is cataract surgery done.

Preparing for surgery: drops, tests and information for the doctor

• Continue your glaucoma drops as usual, unless the doctor has instructed otherwise. Do not stop drops on your own.
• Bring a list of all your drops and medications to the consultation.
• Tell the doctor about previous treatments for glaucoma, such as laser treatment or glaucoma surgery. If you have had glaucoma surgery, the surgeon will plan the cataract surgery so as to preserve the drainage that was created.
• Tests before surgery usually include measuring the eye pressure and examining the optic nerve, in addition to the regular tests before cataract surgery.

General information on preparation is on the page Preparing for cataract surgery.

Eye pressure after surgery

In the first days after cataract surgery, the eye pressure may rise. In most patients this passes, but in people with glaucoma, whose optic nerve is already sensitive, it is important to detect it in time. So patients with glaucoma are checked carefully after surgery, and sometimes receive additional drops to lower the pressure. It is important to attend all the follow-up visits and to continue the drops according to the doctor's instructions.

In some patients the eye pressure goes down after surgery, and sometimes the number of drops can be reduced. This is not guaranteed, and the decision to change the drops is made only by the doctor, according to the pressure measurements.

Narrow-angle glaucoma

In a certain type of glaucoma, narrow-angle glaucoma, the natural lens thickens with age and contributes to narrowing the eye's drainage angle. Removing the lens in cataract surgery can widen the angle and help lower the pressure. So in some of these patients, cataract surgery is also part of the glaucoma treatment, and the doctor may recommend it even when the cataract is not yet very bothersome.

Combined surgery: cataract and glaucoma in the same operation

In some patients, the doctor may suggest combining cataract surgery with a procedure to lower the eye pressure, for example implanting a tiny drainage device. The decision depends on the type of glaucoma, its severity, how many drops are needed and how well the pressure is controlled. Not every patient needs combined surgery, and the doctor will explain the advantages and risks in your case.

Which lens is suitable if I have glaucoma?

A multifocal lens is usually less suitable when there is advanced glaucoma, and in such a case the doctor may recommend a regular lens or an EDOF lens. When the glaucoma is mild and stable, the choice is made according to the condition of the eye and the patient's needs. Information on the options is on the page Types of lenses in cataract surgery.

In a certain type of glaucoma, which is related to a flake-like material in the eye (pseudoexfoliation), the fibers that hold the lens may be weaker. The surgeon takes this into account when planning the surgery.

Recovery and follow-up

Recovery is similar to recovery from any cataract surgery: blurry vision, mild irritation and increased tearing are common in the first days, and full recovery usually takes four to eight weeks. The difference is in the follow-up: in addition to the regular visits after surgery, glaucoma follow-up, including pressure measurement, visual field and examination of the optic nerve, continues after cataract surgery just as it did before. More information is on the page Cataract surgery recovery.

When to contact a doctor

If you have pain that gets worse, redness that gets worse, discharge or a drop in vision, contact a doctor. In people with glaucoma, eye pain with a headache or nausea may indicate a rise in pressure and requires contacting a doctor quickly.

In summary

Glaucoma does not rule out cataract surgery, but it changes the preparation, the planning and the follow-up. Continue your drops as usual unless the doctor has instructed otherwise, tell the doctor about any previous treatment, and attend all the follow-up visits. Surgery restores the vision that was lost because of the cataract, but not the damage caused by the glaucoma, so it is important to talk with the doctor in advance about expectations.