gms | German Medical Science

Purpose: Morphologic and ultrastructural evaluation of human posterior lamellar corneal grafts with history of Descemet-Stripping Endothelial Keratoplasty (DSEK).

Methods: Corneal full-thickness and posterior lamellar grafts (6 each) were obtained from 12 patients (mean age, 74.4 yrs; range, 66–88 yrs; male/female, 5/7; OD/OS, 6/6) following unsuccessful DSEK surgery. All specimens were formalin fixed, paraffin embedded, and evaluated by light and electron microscopic evaluation. A retrospective chart review was performed in all cases.

Results: Clinical indications for DSEK were Fuchs endothelial dystrophy (n=7) and pseudophakic bullous keratopathy (n=5). Reasons for DSEK graft failure and subsequent flap removal included advanced corneal edema, interface haze, and flap detachment. In the majority, posterior lamellar grafts demonstrated mild to severe corneal edema; only 2 specimens showed no stromal swelling. The mean central corneal thickness of the anterior corneal stroma and the posterior lamellar graft was 552.1±144.1 µm (range, 433.1±777.9 µm) and 157.5±55.0 µm (range, 72.0–264.7 µm), respectively. Ultrastructural evaluation revealed lamellar interweaving and large interlamellar spaces. The interface between the anterior corneal stroma and the posterior lamellar graft displayed epithelial ingrowth and pigment-laden cells in 3 specimens. Endothelial cell counts ranged form 0 to 12 cells per HPF.

Conclusions: DSEK advances the treatment options in patients with corneal endothelial dysfunction and low endothelial cell density (e.g., Fuchs endothelial dystrophy or bullous keratopathy). However, surgeon have to be aware of potential intra- and postoperative complications (e.g., endothelial cell loss or flap detachment), which might result in secondary graft failure.