Enucleations are a common procedure performed by not only oculoplastic surgeons, but general ophthalmologist and residents as well, especially in a setting where a significant amount of trauma is encountered.
The most common etiology leading to enucleations at our institution is trauma. Gunshot wounds, motor vehicle accidents and altercations are among the variety of events that lead to significant trauma and rupture of the eye. When the eye is left with no light perception after trauma and the patient suffers from pain, an enucleation may be indicated, especially if the small risk of sympathetic ophthalmia is to be minimized.
In cases of trauma resulting in an open globe, primary repair of the laceration is ideal. Even though the eye may have no visual potential, it is best to allow the patient to adjust to this fact rather than performing a primary enucleation and potentially introducing added psychological damage by removal of the eye before the patient has had time to process the events.
Chronic proliferative diabetes can also lead to significant damage rendering the eye blind and painful. These patients with uncontrolled glaucoma and no further visual potential are often candidates for enucleation.
In evaluation of a patient for enucleation, it is important to first verify the lack of visual potential. This includes consults with colleagues in other disciplines, such as retina and cornea, to ensure that no further procedures can be done to restore functional vision. Pertinent questions in the history include whether the eye is causing pain that interferes with daily activities or wakes the patient from sleep. Examination of the opposite eye with emphasis on protection with polycarbonate lenses at all times is paramount. The affected eye must be thoroughly examined as well for evidence of previously placed hardware that may make dissection more challenging. Of importance as well is to make sure there is no evidence of an intraocular malignancy, in which case it would be extremely important to avoid violation of the sclera and potential seeding of tumor cells. If the anterior segment is opacified preventing a clear view of the posterior pole, an ultrasound can be obtained to rule out a malignancy.
It is important to explain the procedure to the patient, including pre-operative requirements, length of the procedure, implants used, and post-operative management, including what to expect as far as pain. Patients find it helpful if they are shown examples of the implants and prosthetics. I also encourage my patients and inform them that they can eventually return to their normal activities and will be functional in many sports with recommended eye protection. They can also drive if the vision in the remaining eye is adequate by state laws. I often recommend the book "A Singular View" by Frank B. Brady which discusses life with one eye.
I perform the vast majority of enucleations under monitored anesthesia care following a retrobulbar block. Patients go through pre-operative testing, including an evaluation by a medical screener and labs if necessary prior to the surgery. The procedure itself takes about 45 minutes. The video below outlines the procedure.
Spherical implants that are most commonly used have been discussed in my previous article entitled "Spherical Orbital Implants: What to Choose, When and Why". To reiterate, I tend to use the Medpor porous polyethylene implants manufactured by Porex. In the case of severe trauma where extraocular muscles may not be salvageable, I will use a Katena acrylic sphere. The most common size for an adult is 20mm.
Postoperatively, a conformer is placed beneath the lids with antibiotic ointment. A pressure patch is applied for one week. In the majority of cases, post-operative pain is managed with nothing more than oral narcotic pain medication for the first couple of days. The patient returns for the first post-operative visit at one week when the pressure patch is removed. The conformer stays in place for 4-6 weeks to keep the tissues well formed and groomed for the prosthesis. After this time, the patient begins fittings for their prosthesis, which is made to match their opposite eye.
Follow up after the prosthesis is obtained focuses on the remaining eye as well as the socket. Potential complications postoperatively include giant papillary conjunctivitis secondary to protein build up on the prosthesis, infection and extrusion of the implant. Extrusion is rare if an implant with a smooth anterior surface is used, or a porous implant is wrapped in sclera. Proper placement of the implant posteriorly in the socket will also help avoid extrusion.
Most patients have a great cosmetic outcome after fitting of their prostheses. Motility, if the extraocular muscles have been attached to the implant, tends to be good although not as full of range as the normal fellow eye. In my experience, patients tend to be very happy postoperatively as this surgical procedure relieves them of their previous pain. They adjust very well to daily activities and go on to enjoy very balanced lives.