Capsulotomy FAQs: Your questions answered by an expert

In this informative guide, highly respected consultant ophthalmic surgeon Mr Eric Barnes shares his expert insight on capsulotomy, including how it relates to cataract surgery, what to expect from the procedure itself and the associated risks to be aware of.

What is a capsulotomy?

People may undergo cataract surgery to remove the eye’s natural lens when it becomes cloudy. The lens is essentially wrapped in cling film, and once it has been taken out and replaced with an artificial lens, this film (known as the capsular bag) is left behind and can become cloudy following cataract surgery.

In capsulotomy, we break a hole in the capsular bag to remove this cloudiness. In the olden days, this was done surgically but for around the last thirty years, this has been performed with a YAG laser. The laser essentially vaporises a hole in the capsule, typically in an upside down U-shape, clearing the visual axis and your line of vision.

How is a capsulotomy performed?

Capsulotomy is performed using a machine that looks a bit like the average machine that is used to examine the eye, known as a slit lamp. While the capsulotomy is being performed, you will need to keep your head leaning forward onto the machine, just like you do at the opticians.

The procedure takes around five or ten minutes in total and doesn't hurt. Some numbing drops are applied to the eye and then a contact lens is inserted. You will see some lights and then you don't really feel anything. The surgeon focuses the lights on the posterior capsule, hits the button on the laser and it essentially vaporises that space.

Are there any different types of capsulotomy?

As I previously mentioned, the capsule is a cling film-like bag around your eye’s natural lens. Once cataract surgery has been performed, the cells that normally produce your cataract continue to migrate and cause cloudiness behind the implanted artificial lens. In essence, it's like looking through a dirty lens again because these cells have got in between the space of the capsule and the plastic lens inserted in cataract surgery.

Before a plastic lens is inserted in cataract surgery, a hole is torn in the cling film-like bag to remove the eye’s natural lens. The bag itself, however, is not removed and remains in the eye behind the artificial lens. As there is already a hole in the front of the capsular bag, this part doesn’t usually become cloudy. In a posterior (meaning ‘back’) capsulotomy, we punch a hole into the back part of the capsular bag to eliminate this cloudiness.

Very occasionally, the bag itself can shrink. If you've left some cells of some inflammatory conditions on young children, these tend to be quite aggressive and can perhaps cause the capsular bag to contract. When this occurs, the person’s vision is occluded and this requires an anterior capsulotomy.

What are the main risks of capsulotomy?

Thankfully, complications of capsulotomy are very rare. It is a very routine procedure and the vast majority of patients have no real issues following it. Surgical techniques, including those used in cataract surgery and capsulotomy, have advanced significantly over the last twenty to thirty years and we are now using lasers which are more precise and require less energy to be effective. Although all types of surgical interventions have associated risks, fortunately, we are seeing fewer complications of procedures like YAG capsulotomy.

The risks of posterior capsulotomy (YAG laser capsulotomy) are generally understood to be around half of the risk of cataract surgery but without the risk of infection as there is no opening of the eye.

The main risk is of retinal detachment, which is said to occur in around in one in every four-hundred cases. It's more common in people who are short-sighted and perhaps even more so in those who are young and short-sighted. If the retina does detach, surgery is required to reattach it.

In addition, some people can develop fluid (macular oedema) at the back of the eye following capsulotomy. It's not very common and is usually amenable to treatment with eye drops. People may also notice a few more floaters because of the debris generated from the capsule being split.

Another potential side effect is an increase in eye pressure, which can be serious for people suffering with severe glaucoma. For most people, however, this will not cause any real issues. 

How is capsulotomy different from cataract surgery?

You can't perform a capsulotomy before you've replaced the eye’s natural lens in cataract surgery. Capsulotomy is a procedure which may be required sometime after undergoing cataract surgery.

If you require capsulotomy treatment and wish to schedule a consultation with Mr Barnes, you can do so by visiting his Top Doctors profile.