Glaucoma considerations in OOKP

Purpose To study the incidence and prognosis of glaucoma in OOKP eyes and to evaluate methods for detection and treatment of glaucoma following osteo‐odonto‐keratoprosthesis surgery. Methods Retrospective analysis of 49 consecutive patients treated at the national OOKP referral centre in Brighton, UK between November 1996 and September 2009. Data were collected over a 3 month period from December 2009 giving a minimum of 6 months follow up (range: 6 months to 13 years). Data collected include: age at surgery, primary diagnosis, previous surgical procedures (corneal grafts), family history of glaucoma, serial post‐operative cup‐disc ratios and visual fields, glaucoma procedures at any stage, and any OOKP complications. Results A total of 49 patients were included in the study with age ranging from 19 to 88 years (mean 53.5). 14 (28.5%) patients had pre‐existing glaucoma, 25(51%) patients had glaucoma by the end of the study. 12(24.5%) patients developed de novo increase in intraocular pressure. Of the 49 patients, 5 underwent cyclodialysis ,4 had cyclodiode laser treatment, 4 underwent ECP, 5 had a glaucoma tube inserted and 4 had detachment and reattachment of their recti muscles (VRDR ± MRDR). All patients were treated with oral acetozolamide 250mg once daily (except one who is allergic). Sublingual timolol was used in three patients, one of experienced severe side effects and the treatment had to be stopped. Systemic betablockers were used in 3 patients. Conclusion Glaucoma is one of the major complications of osteo‐odonto‐keratoprosthesis. It is difficult to monitor and treat in the OOKP eye. Various treatment modalities have been used. Many patients require long term oral medications and many are not adequately controlled and should have surgical treatment the results of which are not satisfactory. VRDR might represent a safer surgical method to control glaucoma in OOKP eyes.