Pre-cut donor tissue for Descemet stripping automated keratoplasty: anterior hinged lamella on versus off

Abstract

Aims: To compare two different techniques for preparation of pre-cut lamellar corneal tissue for Descemet stripping automated keratoplasty.

Background/methods: Eight donor lenticules were created with a full pass of the microkeratome blade, which resulted in a posterior lamella and a free cap (anterior lamella off group (AL-off)). Contralateral donor lenticules were created with an incomplete pass of the microkeratome blade, which resulted in a posterior lamella and a hinged anterior cap (anterior lamella on group (AL-on)). Endothelial cell density, cellular viability and corneal thickness were evaluated before dissection, and 4 and 24 h after dissection.

Results: Average pre-cut endothelial cell density was 2552.25 (+/-105) and 2572.25 (+/-110) cells/mm(2) in the AL-off group and AL-on group, respectively (p=0.7). At 24 h cell density was 2404.87 (+/-74) in the AL-off group (p<0.01) and 2368.74 (+/-148) in the AL-on group (p=0.01). The mean percentage of trypan blue-stained cells was consistently higher in the hinged AL-on group. Corneal thickness increased by approximately 20% in both groups after 24 h cold storage.

Conclusion: Eye bank-prepared tissue offers the potential advantage of being screened for mechanical stress damage occurring during the automated dissection.