Abstract
Purpose: :
To present clinical outcomes after Pentacam-guided "big bubble" Deep Anterior Lamellar Keratoplasty (DALK) based on corneal pachymetry mapping using Scheimpflug imaging by Pentacam in a retrospective cohort study.
Methods: :
Fifty eyes of fifty patients recieving DALK for keratoconus, keratoglobus and anterior stromal scars were included. DALK was performed with the modified Anwar "Big-Bubble" technique based on corneal pachymetry mapping by Pentacam. Clinical outcome was evaluated as best spectacle corrected visual acuity (BSCVA), endothelial cell count (ECC), refractive astigmatism and central corneal thickness (CCT).
Results: :
BSCVA preoperatively was 20/125 ± 20/160 and increased significantly to 20/50 ± 20/125 (p = 0.001) at 6 months follow-up and to 20/40 ± 20/80 at 1 year follow-up (p = 0.001). ECC was 2138 ± 339 cells/mm2 preoperatively and decreased significantly to 1714 ± 634 cells/mm2 (14,4%) at 6 months follow-up (p = 0.001) and to 1629 ± 478 cells/mm2 (19,9%) at 1 year follow-up (p = 0.001). Refractive astigmatism was preoperatively 7.09 ± 3.52 D (and decreased significantly to 5.26 ± 3.03 D at 6 months follow-up (p 0.05). In case of macroperforation (n = 5) surgery was converted to penetrating keratoplasty (PK). Microperforation (n = 1) as well as development of a double anterior chamber (n = 5) could be handled by an intracameral air injection which resulted in complete reattachement of Descemets’s membrane. No allograft rejection was observed.
Conclusions: :
DALK is an effective alternative to PK in anterior corneal stromal diseases. Pentacam using Scheimpflug imaging creates a corneal pachymetry map on which cut depth of lamellar trephination in DALK can be based on, in order to enhance the safety of the procedure. Further studies are required to provide long-term analysis of these results.
Keywords: cornea: clinical science • keratoconus