Keratoprosthesis - Patient Evaluation and Selection
Information for referring physicians
Corneal graft failure (in non-autoimmune diseases) is the main indication for this procedure.
The Boston Keratoprosthesis consists of two PMMA parts that clamp a corneal graft. The assembly is locked with a titanium ring. The graft is then sutured into the patient's cornea like a standard graft. (The titanium locking ring does not prevent MRI imaging).
Patient evaluation often includes the following components. In some patients it may not be necessary to perform all the following tests; in others, additional tests may be needed.
- Visual acuity, also with hard contact lens when necessary. Accuracy of light projection
- Slit lamp
- Intraocular pressure (pneumontonometry, palpation)
- Evaluation of blink and tear mechanism
- Signs of chronic inflammation
- Phakic, pseudophakic or aphakic
- Optic nerve, macula
- Ultrasound B-scan, A-scan
Other considerations include:
- Blink and tear mechanisms should be reasonably intact
- Vision less than 20/200
- Opposite eye has reduced vision
- Retinal detachment or extreme optic nerve cupping must be excluded
- Intact nasal light projection is important to be able to exclude end-stage glaucoma
- Consider shunt if a patient has very advanced glaucoma (before or after Keratoprosthesis—rarely simultaneously)
Keratoprosthesis surgery has an excellent outcome in patients with non-autoimmune disease, previous graft failures, and no other ocular problems.
If the eye is pseudophakic, plan to keep the intraocular lens in place to prevent vitreous prolapse. Children and individuals who cannot easily be followed frequently and regularly will likely require more involved care. This should be anticipated, and the potential unknown long-term side effects should be discussed with the parents and/or caretakers. Patients with autoimmune disease (Stevens Johnson, ocular cicatricial pemphigoid, uveitis) have a much more guarded prognosis.
To make an appointment, please call 617-573-3240
Click here to view Boston Keratoprosthesis bibliography.