Deep anterior lamellar keratoplasty (DALK) is a safe procedure for all levels of keratoconus, but it’s most effective for those with the severest forms.

In a consecutive interventional case series, researchers included 227 keratoconus eyes that underwent DALK and used the Amsler-Krumeich keratoconus classification to categorize the patients. Stage II included 47 eyes, stage III had 60 eyes and the stage IV group had 120 eyes. Investigators considered postoperative best-spectacle corrected visual acuity (BSCVA), spherical equivalent refraction, mean keratometry, keratometric astigmatism and complications based on keratoconus stage.

The study found no significant differences in postoperative BSCVA, spherical equivalent refraction, mean keratometry and keratometric astigmatism among the groups. Researchers reported improvements in BSCVA were significantly greater in stage III and stage IV compared with stage II. Additionally, they noted the decrease in spherical equivalent was significantly greater in stages III and IV compared with stage II, and mean keratometry decreased more in stage IV compared with stages II and III. The study groups were comparable with respect to intraoperative Descemet’s membrane perforation, the rate of successful big-bubble formation, suture-related complications and graft rejection, the investigators noted in their paper on the study.

“DALK is a safe and effective procedure for the treatment of all stages of keratoconus,” they wrote. “This technique of corneal transplantation is more effective in eyes with severe keratoconus compared with those with moderate keratoconus.”