If you have glaucoma and need cataract surgery

If you have glaucoma and need cataract surgery, you should explore whether you can have a pressure-lowering procedure at the same time as your cataract operation. Advances in cataract surgery and glaucoma micro-stents or laser treatment mean that it’s possible to treat both conditions in the same operation without compromising the outcome of the cataract surgery. The combined procedure is known as a “Phaco Plus Procedure”, or cataract surgery with minimally/micro-invasive glaucoma surgery (MIGS.)

Glaucoma treatment has improved significantly over the past ten years, with drops that are easier and more comfortable to take, and non-surgical laser options like Selective Laser Trabeculoplasty that are highly effective and safe.

In my previous blog posts, I have discussed how cataracts come to everyone eventually as the human lens ages with time. The extent to which cataracts affect you in your day-to-day life will form the basis of your decision whether to have surgery.

What if you have glaucoma and cataracts that now need surgery? You may be surprised to know that you can have treatment for your glaucoma at the same time as having the cataract removed and that this can reduce your dependence on pressure-lowering drops. In some cases, it means that you can stop using your drops for a while.

We can reduce eye pressure at the time of cataract surgery by 20% or more

  • First, by placing stents inside the eye to allow the internal fluid to drain better, improving the outflow and therefore lowering the internal eye pressure.
  • Second, by applying a laser to the glands that produce the aqueous fluid inside the eye (endocyclophotocoagulation or ECP). This turns down the inflow.

These processes can reduce the need for glaucoma drops after your cataract operation. The main risk with operating inside the eye is the risk of infection. It is helpful to treat glaucoma when you are already inside the eye removing the cataract.

Ms Crawley and her colleagues at The Western Eye Hospital at Imperial College Healthcare NHS Trust were one of the first teams – in one of the biggest centres in the UK – to offer ECP and suprachoroidal stents.

Failing to provide combined treatment for glaucoma with cataracts in one operation may be an opportunity missed. Combined treatment may improve the longer-term pressure control. It may also reduce the burden on the patient of having to take eyedrops – a lifelong treatment.



The pressure inside the eye relies on the amount of internal aqueous fluid that the eye produces. It also relies on the rate at which it drains through the eye’s internal outflow pathway. This fluid and drainage process is different to tears, which are external to the eye.

Endocyclophotocoagulation (ECP) means applying a laser to the ciliary body that produces the aqueous fluid under direct endoscopic vision.

Endoscopy is the technique that passes a camera into spaces inside the human body. This allows us to identify issues, however small, with certainty. Doctors who examine the stomach and intestines also use this method.

Reducing the amount of aqueous fluid produced is like turning down the tap – reducing the inflow part of the pathway.

The specialist carries out the ECP through the same incisions used for the cataract operation and adds 20 minutes to the procedure. The surgeon can perform this operation under the same anaesthetic used for the cataract surgery.

A micro-stent, often the iStent or the CyPass, is a snorkel/tube device that makes it easier for the aqueous fluid to drain out of the eye. It is placed at the end of the cataract operation and adds 10-15 minutes at the end of the cataract procedure. The iStent is a small titanium stent that the specialist inserts through the trabecular meshwork – the conventional outflow drainage pathway inside the eye. The CyPass is a stent that is inserted into the suprachoroidal space, creating a new pathway for fluid to drain and thereby lowering the pressure.

These micro-stents are currently the smallest implants used in the human body.
They are not detectable to the naked eye. Only an ophthalmologist can visualise them by looking into the drainage channels using a goniolens.

Clinical trial data supports the use of the implants, which are also approved by NICE and the FDA for use in patients who have glaucoma and need cataract surgery.

Ms Crawley has used them in cases of mild to moderate glaucoma, aiming for a reduction in dependence on drops. She has also used them in cases of more complex disease, where they can delay the need for more complicated glaucoma surgery, such as tube and trabeculectomy surgery, without compromising the outcome of this surgery either.

They are a fantastic addition to the treatment options for glaucoma specialists. Imagine if you were able to stop using your drops for a period because a stent or laser treatment was controlling the pressure?

What should I expect after combined cataract and minimally invasive glaucoma surgery?

The post-operative recovery period is similar to that for the cataract surgery alone. Yet in this case more than one procedure is involved. It is usual to increase the frequency of the anti-inflammatory drops after the surgery from four times daily to six times daily in some cases. You may need the drops for six weeks rather than four weeks.

If you have glaucoma and are thinking about cataract surgery, it is highly advisable to see a surgeon who specialises in both to get the maximum treatment benefit from one operation.

In my opinion, as a glaucoma specialist, it is a missed opportunity to operate only on the cataract and not do something for the eye pressure at the same time.