Enucleation

It is a surgical procedure, the purpose of which is complete removal of the eye, that is to say, all the internal content of the eye, of the sclera (the external layer that encompasses the eye) and a portion of the optic nerve.

This technique is different to evisceration, where only the intraocular content is removed, leaving intact the "casing of the eye" (similar to keeping the shell of an egg and just removing the yolk and the white) without modifying the physiological muscular insertions and thus respecting eye movements. 

In both techniques, there will be a marked absence of the content of the orbit (the cavity that protects and houses the eye and its supporting structures) which is why the loss of volume needs to be made up for by putting in an internal implant in the same procedure. 

The indications of enucleation are few and very specific. The main reason why we would recommend it is in the case of a malignant intraocular tumour that evades other more conservative treatments, prevailing over aesthetics and giving patients the maximum options for survival. 

The two malignant tumours that most commonly require enucleation are choroidal melanoma in the case of adults; and retinoblastoma in the case of children.

Another indication would be severe eye trauma with serious malfunctioning of the membrane and eye contents, which cannot be repaired with an evisceration. 

Evisceration is the technique of choice in other circumstances like painful blind eyes not caused by a tumour, serious intraocular infections that cannot be controlled using medical treatment, blind eyes with phthisis (that lose volume and begin to atrophy), etc.

It is a surgical procedure that we perform in theatre and under general anaesthesia, although in isolated cases it can be performed under local anaesthesia and profound sedation. 

With this technique, an ophthalmologist specialising in cosmetic eye surgery extracts the whole eyeball including the sclera and a portion of the optic nerve and puts spherical-shaped internal implant of the same size in its place to restore the volume lost. 

Previously we will have removed the intraocular muscles that are responsible for eye movement, then suture them to the implant and maintain the motility of the eyeball. 

Regarding internal protheses, we must be noted that there is a wide variety. They can be classified based on their component material (silicone, bioceramics, porous polyethylene or hydroxyapatite) and by size and shape. The choice of one or another will depend on the characteristics of the patient's eye. The choice should always have the aim of getting a comfortable fit and an optimum cosmetic result. 

A short hospital admission is recommended, usually for one night only, where the patient is monitored and wears a compression bandage to avoid postoperative haemorrhages.

Once the patient has been discharged, daily hospital treatments will be provided the week after surgery. During these, the cavity will be checked and the bandage will be changed.

After a week, the provisional external prosthesis is fitted with the aim of preventing the cavity from contracting. After a month, the prosthetist implants the definitive external prosthesis.

It is a simple and very safe surgical technique in the hands of a specialist surgeon. 

We require postoperative medication combining antibiotics to prevent infection, and anti-inflammatories and painkillers to combat the inflammation and manage the immediate postoperative pain. 

Patients may also suffer from a slight degree of swelling, which can be controlled by applying ice to the area. They may notice plenty of secretion that usually stops by washing the eye with saline solution.

It is important that patients are advised to take relative rest, avoid physical exercise and lifting weights, particularly during the first few days after the operation. 

Over the long-term and in a few cases, the tissues covering the internal prosthesis may thin out, causing a prosthesis extrusion. This situation would require another surgical procedure for its resolution. 

Extrusion is very uncommon when we have used a prosthesis made of a porous material (for example, hydroxyapatite or polyethylene) as these materials facilitate vascularisation of the implant and improve their integration into the tissues.