by Quang La
Image by Quang Tri Nguyen via Unsplash
For those with severe, bilateral corneal blindness, osteo-odonto keratoprosthesis (OOKP), popularly referred to as "tooth-in-eye" surgery, is a highly specialized and intricate medical treatment that restores eyesight. With this novel approach, a prosthetic cornea is made using the patient's own teeth and jawbone tissue, and it is then delicately implanted inside the eye.
When is Tooth-in-Eye Surgery Necessary?
OOKP surgery is only appropriate for patients with bilateral end-stage ocular surface disease (OSD), a disorder that causes total blindness due to significant deterioration to the cornea and conjunctiva, the transparent, protective membrane covering the front of the eye. When more possibilities for treatment, such limbal stem cell transplants and conventional corneal transplants, have not worked well or pose too great of a risk to the patient, this technique is usually taken into consideration.
OOKP surgery may be necessary due to various common underlying reasons, including as autoimmune illnesses causing severe dry eye, chemical or thermal burns to the eyes, Stevens-Johnson syndrome, persistent trachoma producing in corneal scarring, and graft-versus-host disease.
Eligibility Criteria for Tooth-in-Eye Surgery
OOKP surgery has strict eligibility criteria to ensure the best possible outcomes for patients. Candidates must meet the following requirements:
Bilateral corneal blindness
Exhaustion of all other treatment options
Good overall eye health, with no damage to the retina, optic nerve, or other critical structures
Healthy oral and dental structures, including a mature, fully developed dental arch
Prospective candidates are put through a thorough examination process that includes extensive oral, psychological, and ophthalmological tests to see if they are a good fit for the treatment. Because of the higher risk of problems, younger individuals with weak dental arches are usually not regarded as feasible candidates.
The Intricate Surgical Technique
The OOKP procedure is a multi-stage process that involves several complex steps:
Preparing the Eye: The surgeon first removes the damaged surface layer of the eye and replaces it with a graft of the patient's own cheek tissue.
Extracting and Shaping the Tooth: A canine or premolar tooth, along with a portion of the surrounding bone, is carefully extracted from the patient. This tooth-and-bone structure is then shaped and polished to create the OOKP.
Incorporating the Optical Device: A clear, cylindrical plastic optical device is embedded into the center of the prepared tooth-and-bone structure, forming the complete OOKP prosthetic.
Implanting the OOKP: After the graft on the eye's surface has fully healed, the surgeon transfers the OOKP from the patient's cheek to the eye, centering the optical cylinder over a hole created in the cornea and securing it in place.
Risks and Complications of OOKP Surgery
While OOKP surgery has a high overall success rate, ranging from 88.25% to 93.9%, it is not without its risks and potential complications. These can occur at various stages of the procedure, including:
Corneal perforation during the initial eye preparation
Damage to teeth, jaw, or salivary glands during the extraction and shaping of the tooth
Oral infection or scarring at the graft site
Overgrowth or necrosis (tissue death) of the graft over the eye
Severe inflammation inside the eye (endophthalmitis)
Resorption (breakdown) of the tooth-bone lamina
Hemorrhaging in the vitreous humor
Patients who undergo OOKP surgery require lifelong specialized follow-up care and management to address these potential complications.
OOKP Surgery: A Life-Changing Intervention for the Severely Blind
Osteo-Odonto Keratoprosthesis, or "tooth-in-eye" surgery, is a remarkable and innovative procedure that can restore vision for individuals with severe, bilateral corneal blindness when all other treatment options have been exhausted. By leveraging the patient's own tooth and bone to create a prosthetic cornea, OOKP surgery represents a remarkable advancement in the field of ophthalmology.
However, this treatment should only be used as a last resort for patients who have exhausted all other options due to its complexity and hazards. To manage the potential difficulties, candidates must go through a thorough evaluation process and get specialist treatment for the rest of their lives. Notwithstanding these difficulties, OOKP surgery can be a game-changer for people whose severe, bilateral corneal blindness is incapacitating.
MCR Committee: Surgery
References:
McManes, A. (2024b, May 14). Tooth in eye surgery. All About Vision. https://www.allaboutvision.com/conditions/cornea/tooth-in-eye-surgery/
Osteo-odonto-keratoprosthesis. (2024, May 25). Wikipedia. https://en.wikipedia.org/wiki/Osteo-odonto-keratoprosthesis
Restoring Vision with ‘Tooth in Eye’ Surgery - CAKE. (2020, January 21). CAKE. https://cakemagazine.org/restoring-vision-with-tooth-in-eye-surgery/