What is an orbital decompression operation?
Orbital decompression surgery is an operation on the eye socket (orbit) that reduces the protrusion of the eye or eyes that can occur with thyroid eye disease (or TED, sometimes called thyroid orbitopathy, Graves’ eye disease, Graves’ ophthalmopathy or Graves’ orbitopathy). The main reasons for performing the operation are to reduce the protrusion of the eye (bulging forwards of the eye or eyes, sometimes called exophthalmos), and in some patients with severe thyroid eye disease (TED), to relieve pressure on the optic nerve (the nerve connecting the eye to the brain) that can cause reduced vision.
The operation may be performed on one or both (bilateral) eye sockets at the same operation.
Orbital decompression surgery is just one part of the management of patients with TED. TED is managed in conjunction with your thyroid specialist (endocrinologist) and GP, and the control of the thyroid hormones is very important. Other operations may be required after orbital decompression surgery, and can include surgery for double vision and for staring or retracted and puffy or swollen eyelids.
What is done in an orbital decompression?
The aim of an orbital decompression is to make more room for the swollen fatty tissue and muscles behind the eyes that cause the eyes to bulge, and can sometimes cause pressure on the optic nerve, reducing vision. More room is created by removing bone from the walls of the bony eye socket (the orbit) to make the orbit bigger and allow the eye to settle back into its socket. Sometimes, fatty tissue is also removed to make more room.
The amount of bone that is removed will depend on the severity of the TED. One, two or three of the four walls of the orbit can have bone removed from them, and the more bone that is removed, the greater the reduction in the protrusion of the eyes. The roof of the orbit that separates the orbit from the brain above the eyes is not removed, but bone to the outer side, towards the temple (the lateral or outer wall) is commonly removed, followed by the inner wall (between the orbit and the nasal cavity), then the orbital floor (between the orbit and the cheek sinus).
What are the benefits of an orbital decompression operation?
The potential benefits of an orbital decompression are:
- Reduction in the protrusion or bulging of the eye(s)
- Improved vision if the optic nerve has been squeezed by the swollen muscles behind the eye
- Improved comfort: many patient with more severe TED have aching or pressure behind the eyes which is improved by orbital decompression surgery. Additionally, the stinging, grittiness and watering of the eyes that is common in TED is often improved after orbital decompression
- Reduced staring appearance of the eyes: there is often a small reduction in the gap between the upper and lower eyelids, but some patients will still require surgery for their eyelids after an orbital decompression
What sort of anaesthetic is used?
A general anaesthetic is always used for an orbital decompression.
How long will I need to stay in hospital?
You will need to stay in hospital for at least one night after the surgery, and sometimes two or more nights.
Where will the scars be?
For orbital decompression surgery, the only externally visible scar is a short scar that runs down at an angle from the outer corner of the eye in one of the “smile lines”. This heals well and after some months is barely noticeable. All other scars are inside the eyelids and not visible.
What problems can occur with orbital decompression surgery?
All operations carry risks, and orbital decompression is no exception. Problems are uncommon but can include:
- Excessive swelling and bruising: it is normal for there to be some bruising and swelling, and this normally increases in the first few days after surgery, then begins to fade. Sometimes the thin skin on the surface of the eye (the conjunctiva) can swell and look like a blister (sometimes pale, sometimes red) on the white of the eye.
- Double vision: often present before surgery in patients with TED, but can be more noticeable after orbital decompression, or can appear for the first time after orbital decompression. If it does occur, it may be temporary, but in some patients, the double vision may persist and require more surgery to correct it. It can nearly always be treated.
- Numbness: some numbness around the eye is very common after orbital decompression surgery. Usually this is over the cheek bone in a small area that can shrink over time. Sometimes the cheek below the eye and the upper lip and teeth can be numb, but this nearly always recovers. The side and tip of the nose can sometimes be numb also, but this is much less common.
- Loss of vision in one eye: this is a very serious problem, but extremely rare. It can occur when there is uncontrolled bleeding behind the eye during or after the operation. The risk of this happening is less than 1 in many hundreds.
- Sinus problems: because some of the bone that is removed opens up some of the sinuses next to the nasal cavity, occasionally, the sinuses may not work properly and can become blocked and filled with fluid, or sometimes infected. This is rare, and can be treated.
- Infection: this is rare after orbital decompression surgery.
- CSF leak: very rarely, damage to the covering over the brain during removal of bone can lead to leakage of CSF (cerebro-spinal fluid, the fluid surrounding the brain). Even if this occurs it can usually be dealt with at the time of surgery without further problems arising. Extremely rarely, cases of stroke or bleeding on the brain have been reported, but never in this practice.