Donor Descemet-off versus Descemet-on deep anterior lamellar keratoplasty: a confocal scan study.

PURPOSE: To compare confocal features of grafts following deep anterior lamellar keratoplasty (DALK) using a donor without Descemet membrane (DM) versus a full-thickness donor with intact DM and endothelium.

METHODS

This retrospective comparative study examined 45 eyes from patients with keratoconus who underwent DALK using the big-bubble technique. The big-bubble technique yielded a bared DM in all keratoconic eyes. Twenty-seven eyes received tissue from a donor without DM (group 1), while 18 received tissue from a full-thickness donor with an intact DM and endothelium (group 2). A group of normal eyes (n = 28, group 3) served as controls. Confocal microscopy was used to determine keratocyte density, explore the donor-recipient interface including clarity and reflectivity, evaluate endothelial cell density and morphology, as well as measure interface depth and central corneal thickness.

RESULTS

Mean follow-up duration was 20.2 ± 8.6 months and 29.6 ± 17.0 months in groups 1 and 2, respectively (p = 0.13). Confocal scan demonstrated that the keratocyte profiles and distribution were more similar to normal corneas in group 2. Significantly more severe interface haziness was observed when donor DM and endothelium was retained (mean interface reflectivity value of 102.7 ± 22.1 versus 161.7 ± 30.0 light reflectance units in groups 1 and 2, respectively, p<0.001).

CONCLUSIONS

Graft cellular profiles and healing response at the donor-recipient interface can be profoundly affected depending on whether donor DM and endothelium is removed or retained.