Characterization of Zig-Zag Femtosecond Laser-Assisted Keratoplasty Wound Configuration Using Anterior Segment OCT
Narrative Responses:
Purpose
To evaluate wound architecture of femtosecond laser assisted keratoplasty (FLAK) using the zig zag wound configuration.
Methods
Retrospective chart and imaging review. Charts of all patients who underwent FLAK with zig zag trephination performed by a single surgeon at a single institution during the academic year of 2012 were reviewed. Anterior segment OCT (AS-OCT) was performed to evaluate the graft host junction. Thickness of the wound was measured from the epithelial surface to the anterior chamber. Each measurement was taken from approximately the same 3 or 9 o’clock position.
Results
Five eyes of 5 patients underwent FLAK for indications of keratoconus or corneal opacity. The zig zag wound configuration could be easily recognized at all time points. All three patients showed contraction of the wound during follow up. The most rapid change in wound thickness for the two keratoconic patients occurred during post op months 1-3 (decreases of 131 and 152 microns). For the HSV scar patient, the most rapid change occurred during post op months 3-6 (decrease of 85 microns). Overall the keratoconic patients showed a larger amount of wound thickness change during the follow up.
Conclusion
The femtosecond laser can be used to create custom-shaped incisions, such as the zig-zag configuration, for corneal transplantation that can be verified by optical coherence tomography. The zig zag shaped femtosecond laser incision pattern provides theoretic advantages with respect to wound architecture, including scar contracture as seen by AS-OCT.