Vitrectomy: what happens, risks and recovery

The vitreous is the clear, jelly-like material that fills the space behind the lens. Usually it is harmless and nobody notices it. It becomes a problem when it is clouded with blood, when scar tissue grows across it and pulls on the retina, or when something has to be reached that lies behind it.

One Hull leaflet lists the usual reasons: clearing blood that has leaked from retinal blood vessels into the gel, controlling scar tissue that can form in diabetes or after a blocked retinal vein, removing a foreign body after an injury, and clearing cloudy gel after a severe internal infection. Plymouth leaflets written for retinal surgery patients also describe gas or oil being used to hold the retina in place, which fits with the way vitrectomy is used in retinal detachment surgery.

It is not a routine operation for floaters or mild blurring. The same leaflet is clear that successful surgery will usually bring back some sight but may not restore it completely, so the decision rests on what vision is at risk and what the alternatives are. Some retinal problems can be treated with laser or an injection instead, and your surgeon will explain whether those fit your eye.

Before the date is given you attend a pre-operative assessment. According to the Hull leaflet this covers questions about your general health, sometimes blood tests and a heart tracing, measurements of the eyes, and a list of your tablets and allergies. Writing medicines down beforehand makes the visit quicker.

On the day the same leaflet asks you to take your usual medicines unless told otherwise, to eat and drink normally unless you have been instructed not to, and to leave make-up, nail varnish and jewellery at home apart from a wedding ring. Your pupil is widened with drops once you arrive. Fasting instructions can differ between units and with the type of anaesthetic, so follow the written instructions you are given.

• Arrange for someone to take you home, as you cannot travel alone with a covered eye.

• Ask beforehand how long you may need to hold a particular head position, and set up a chair, pillows or a face-down support at home.

• Mention blood thinners, diabetes treatment and any previous reaction to eye drops at assessment.

Vitrectomy is a day-case operation in the units whose leaflets were read for this page, although you can expect to be in hospital for most of the day. Local anaesthetic numbs the eye, and the Hull leaflet notes that you may still be aware of lights and shadows inside the eye while it works, which is normal because the retina is still active.

The surgeon makes three small openings in the white of the eye and removes some or all of the gel, replacing it with saline. The retina is then examined for weak areas, and the leaflet says freezing treatment or laser may be applied to those areas to lower the chance of a later detachment. Depending on the problem, the surgeon may fill the eye with a gas bubble or with silicone oil to support the retina while it heals.

You go home with a pad and shield. The Plymouth leaflet says the pad is worn for the first night only and removed in the morning, while the plastic shield is kept for night-time wear for at least the first week to stop you rubbing the eye in your sleep. The Hull leaflet gives eight hours for the patch.

One Plymouth leaflet lists the gases SF6, C2F6 and C3F8, plus silicone oil and a heavy silicone oil, as the possible fillings. A gas bubble is slowly absorbed by the eye, and a Leeds leaflet gives roughly one to four weeks depending on the gas, while the Hull leaflet says flying must wait until the gas is gone, which it says can take up to eight weeks. Because the published figures differ, the practical rule is to wait for your own surgeon to tell you the gas has gone.

Positioning is the demanding part. One Plymouth leaflet asks for a posture such as face down or cheek to pillow for up to 14 days in the daytime, 50 minutes in each hour, while another version from the same trust gives up to five days, day and night. The difference shows that instructions depend on the surgeon and the reason for surgery. Silicone oil usually has to be removed at a second operation some months later.

While the bubble is present, do not fly, swim or take part in strenuous activity. Wear the wristband, and if you need a general anaesthetic for anything else you must tell the anaesthetist about the gas.

The Hull leaflet lists infection inside the eye, which it calls very rare but able to cause serious loss of sight, bleeding, retinal detachment at any time after surgery, raised pressure needing drops, inflammation, eyelid bruising and allergy to medication. It also says almost all patients develop a cataract more quickly than normal, because the internal fluid has been disturbed and gas is present, and that the lens can be removed during the same operation or later.

None of the leaflets read gave percentages for these problems, so none are quoted here. Ask your surgeon how your own reason for surgery changes the picture, because risks differ between a simple bleed clearance and a complicated detachment repair. Staying face down for long periods also raises the chance of a clot in the leg, which is why the Plymouth leaflets ask you to move your ankles and knees while positioned.

Expect a red, swollen, sometimes sticky-looking eye and very little useful vision at first if gas is present. Some discomfort is normal and is managed with simple painkillers, but not extra aspirin if you take it regularly for another reason. Drops continue for several weeks. The Hull leaflet suggests returning to work in about one to two weeks, longer if the job is physical, and avoiding swimming for eight weeks.

A separate timeline page covers the weeks in more detail.

The leaflets agree on what needs a prompt call to the eye unit that treated you: more pain, a red or sticky eye, further loss of vision, or a new shadow or curtain in the side vision, with floaters or flashes similar to those before surgery. Outside unit hours, use the on-call eye service the leaflet names or NHS 111.

A hot, swollen, painful calf or sudden breathlessness with chest pain should be treated as an emergency; the Plymouth leaflets say to contact a GP or call 111 as soon as possible for suspected clot symptoms, and sudden breathlessness with chest pain is an emergency, so call 999.

Useful questions are: which gas or oil is planned and for how long; what head position, for how many hours; when should I expect to be able to drive and fly; will a cataract be dealt with now or later; and who do I ring at night.

In the NHS, vitrectomy is part of retinal services and is organised around the clinical urgency of the problem. Private care mainly changes timing, choice of surgeon and facilities rather than the operation itself. Ask any provider for their written aftercare instructions and out-of-hours arrangements.