gms | German Medical Science

To determine the primary success and recurrence rate of amniotic membrane transplantation (AMT) for treatment of persistent corneal epithelial defects (PEDs) in eyes after one or more previous penetrating keratoplasties (PKs).

AMT was performed in 24 eyes of 24 patients for erosions without stromal defect (n=6) and ulcers (n=18), which were resistant to medical therapy. All the patients had undergone one (42%) or more PKs prior to AMT. After removal of the epithelium and pannus (if present), one or more layers of AM depending on the depth of the lesion were fixed with interrupted 10-0 nylon suture. Three different surgical techniques were performed: 'inlay' or 'graft' (n=3), 'overlay' or 'patch' (n=5), and 'sandwich' or combination of 'graft' and 'patch' (n=16). Main outcome measures included surgical success (SS), if the epithelium was closed within four weeks after AMT, and recurrence (R), if a new epithelial defect developed during follow-up (15 ± 12 months) after the complete epithelial closure.

The rate of SS was 70% (erosions: 80%, ulcers: 67%) and was found to be inversely proportional to the number of previous PKs. Moreover, the defects limited only to the centre of the corneal graft had a higher success rate (central: 100%, non-central: 61%). The diseases did not differ essentially for both SS and primary failure groups. Seven out of sixteen successful eyes (44%; erosions: 75% vs. ulcers: 33%) had a R after a mean follow-up of 16 ± 13 months. The rate of SS was highest (81%) and the rate of R was lowest (38%) with the 'sandwich' technique.

AMT may be beneficial in the treatment of PEDs after PK. Especially when the 'sandwich' technique is applied, the primary success rate is comparable to that without previous PK. In contrast, recurrences seem to be more frequent after PK. Treatment of systemic or other associated ocular diseases is indispensable for success.