"Groove and Peel" Deep Anterior Lamellar Keratoplasty: How Deep Can You Go?

Purpose:The aim of the current research was to measure the thickness of the residual central corneal bed after performing the manual "Groove and Peel" deep anterior lamellar keratoplasty (GP-DALK) technique on human cadaveric eyes.Methods:The manual GP-DALK technique was performed on 6 human cadaver eyes by an experienced corneal surgeon. After surgery, the eye globes were fixed in 10% buffered formalin and embedded in paraffin. For each eye, 4-m-thick hematoxylin and eosin sections involving the pupillary axis were obtained and examined. Using an image-processing software, 2 observers measured the corneal thickness of the residual central corneal bed and the peripheral corneal rims.Results:The overall mean central corneal bed thickness was 35.5 ± 12.9 m, whereas the mean right and left peripheral rim thicknesses were 993.0 ± 141.1 and 989.3 ± 147.1 m, respectively (P = 0.0006). In most corneas, the level of dissection reached almost to the pre-Descemetic collagen (Dua) layer.Conclusions:The GP-DALK technique is effective in removing most of the corneal stroma and may be non-inferior to "big-bubble" deep anterior lamellar keratoplasty in some cases.