Transmucosal Boston Keratoprosthesis Type I in a Patient With Advanced Ocular Cicatricial Pemphigoid

To describe a novel surgical technique using the Boston Keratoprosthesis (KPro) type I in a patient with advanced ocular cicatricial pemphigoid (OCP) using oral mucosa for covering the prosthesis.

We present the case of an 85-year-old man previously diagnosed with type 2 diabetes and advanced OCP nonresponsive to immunosuppressive treatment, whose best-corrected visual acuity was light perception and projection in both eyes. After examination, Boston KPro type I in the right eye was contemplated because osteo-odonto KPro and Tibial bone KPro were not feasible because of the patient's osteoporosis and edentulism. Reconstruction of the ocular surface was first performed using oral mucosa to release the symblepharon and try to deep the fornices. Three months later, the oral mucosa was lifted, and the Boston KPro type I was implanted using the patient's own cornea. Then, a modification of the standard surgical technique was carried out, replacing the use of contact lens for covering the prosthesis with an oral mucosa graft with a central trephination as an alternative option in fornix foreshortening cases.

After 11 months, visual acuity was stable to 0.2 decimal. No postoperative complications have been encountered, and prosthesis was in place.

The surgical technique of transmucosal Boston KPro type I may be considered a surgical alternative in patients with advanced OCP who present with severe fornix foreshortening, where osteo-odonto KPro or Tibial bone KPro cannot be performed due to osteoporosis or edentulism or when the Boston KPro type II is not readily available.