Abstract
Purpose:
To evaluate the preoperative indications, postoperative complications, retention rate and surgical outcomes of patients with Boston Type I (formerly Dohlman type I) Keratoprosthesis in an international center.
Methods:
An observational and retrospective study was performed with review of the medical records of patients who underwent Boston Type 1 Keratoprosthesis (KPro) implantation at Instituto de Oftalmología Conde de Valenciana (an ophthalmologic reference center) in Mexico City, Mexico. The variables analyzed included surgical indication, initial and final visual acuity, previous keratoplasties, postoperative complications and retention rate.
Results:
22 eyes of 21 patients with a median age of 49.5 years (range 24 - 90 years), median follow-up after keratoprostheses of 14 months (range 3 to 124 months). Preoperative visual acuity was worst than 20/100 in all cases. Indications for surgery included: corneal dystrophies in 4 patients (19.0%), ocular burns (2 patients, 9.5%), aniridia (2 patients, 9.5%), bullous keratopathy (3 patients, 14.2%), Stevens-Johnson syndrome (2 patients, 9.5%), severe ocular rosacea (1 patient, 4.7%), among others. One patient with binocular keratoprostheses had rheumatoid arthritis with severe ocular surface disease. In 16 eyes (76.1%), previous penetrating keratoplasties were attempted with failure. Four patients were treated with keratoprosthesis assisted with intraprosthetic amniotic membrane. Postoperative complications included retroprosthetic membranes in 4 patients (19.0%), retrolental membranes in 2 (9.5%), retinal detachments in 2 (9.5%) and endophthalmitis in 2 (9.5%). Of the 22 keratoprosthesis implanted, 4 have been removed, obtaining a retention rate of 81% during follow-up; in 2 cases keratoprostheses re-placement was performed and 2 cases presented endophthalmitis, one requiring evisceration. 14 eyes had a final visual acuity equal or better than 20/400 (with a median of 20/60).
Conclusions:
Indications for Boston Type I keratoprosthesis are varied, and usually reserved for very complex cases with previous failed penetrating keratoplasties as a common characteristic. Postoperative complication and retention rates remained similar to other series. Boston type I keratoprosthesis implantation is increasing abroad, it is important to report the outcomes from different venues around the world.