Cryopreserved amniotic membrane transplantation for the management of symptomatic bullous keratopathy

Background: To report the results of cryopreserved human amniotic membrane transplantation for the management of symptomatic bullous keratopathy. Methods: Prospective non-comparative interventional case series study. Consecutive cases with symptomatic bullous keratopathy for more than 12 months not amenable to conservative treatment were managed with amniotic membrane transplantation. They were recruited over a 5-year period (September 1999 to November 2004) in one referral centre. Only one eye of each patient (the worse affected eye in bilateral cases) was operated. A 360 degree conjunctival peritomy was followed by removal of the diseased corneal epithelium. Amniotic membrane was transplanted over the cornea as a patch and sutured to the free conjunctival edges. Primary outcome measures were ocular pain and epithelial defects; secondary measures were visual acuity and ocular surface inflammation. Results: Four out of 85 recruited cases did not complete the minimum observation of 12 months and were excluded from the study. The mean follow-up period for the remaining 81 cases was 21 +/- 4.2 months (range 14-34 months). Seventy-one (87.6%) eyes became asymptomatic with healed epithelium, seven required repeated amniotic transplantation and three underwent penetrating keratoplasty. Visual acuity improved in 64 (79%) patients and remained unchanged in 14. No complications were recorded. Conclusions: Amniotic membrane transplantation is an efficient and safe treatment for symptomatic bullous kerato pathy, when penetrating keratoplasty is not available. It has been shown to alleviate pain, promote corneal epithelialization and reduce conjunctival inflammation whereas in some cases it may also improve visual acuity.