Spectral domain OCT‐assisted “big bubble” deep anterior lamellar keratoplasty in keratoconus patients

Abstract

AbstractPurpose To visualize intraoperative changes of corneal thickness and bubble creation process using spectral domain OCT.Methods 15 patients underwent DALK performed using “big bubble” technique. Surgeries were assisted with intraoperative spectral domain OCT imaging (The iVue from Optovue Fremont Calfornia USA). Corneal thickness was measured preoperatively, after manual pre‐cutting and after the big‐bubble creation.Results Manual pre‐cutting of corneal stroma revealed residual bed thickness of 240‐270 µm (mean 256 µm). When residual corneal bad was thicker than 250 µm, the 27G needle was used for big‐bubble creation, when it was thinner than 250 µm, 30G needle was used. After injection of an air bubble, in 11 eyes Descemet’s membrane was completely separated from stroma, that was shown on OCT scans. In 4 eyes the separation was incomplete that was also clearly visible on OCT images. In one eye OCT imaging showed completely unseparated Descemet’s membrane and the additional injection of air bubble was necessary to effectively create the air space between the corneal layers.Conclusion Intraoperative imaging with Spectral domain OCT provides high‐resolution imaging of cornea bed thickness including visualization of the air‐bubble formation. This technique could provide enhanced information for the corneal surgeon during lamellar procedures such a DALK.