Purpose: To compare three microkeratome-assisted techniques for the preparation of ultrathin (UT) grafts for Descemet stripping automated endothelial keratoplasty.
Methods: After dissection with a 300-μm microkeratome head in 40 donor tissues, a second cut was performed with a 130-μm head either after manual stromal hydration (group A, n = 10) or osmotic hydration at the eye bank (group B, n = 10) or with a 50- or 90-μm head, depending on residual bed thickness (group C, n = 10); no further dissection was performed in the control group (group D, n = 10). Corneal thickness and endothelial cell (EC) count were determined at all appropriate stages. Statistical analysis was performed using a Fisher exact test.
Results: Final graft thicknesses in groups A (89.1 ± 34.1μm), B (84.1 ± 18.6 μm), and C (72.1 ± 10.1 μm) were significantly lower than in group D (201.9 ± 25.3 μm) (P < 0.001). EC loss did not differ significantly among the groups. Multiple areas of Descemet detachment were seen in 4 of 10 corneas of group A.
Conclusions: All methods proved equally efficient in producing UT grafts, but stromal hydration induced tissue structural changes. EC loss was unaffected by the additional manipulation required to prepare UT grafts.