ByLimb: Development of a New Technique to Implant Intracorneal Ring-Segments from the Perilimbal Region

Abstract

A new technique that allows implanting intracorneal ring-segments (ICRS) from the limbal zone is described. Using a femtosecond laser (FSL), a 360° corneal tunnel is created with an internal diameter of 5.4 mm and an external diameter of 7.0 mm, with a wider area (0.2 mm inner and 0.2 mm outer) in the upper 60° of the tunnel (called landing zone). Next, a 4.36 mm-long corneal-limbal incision was created with the FSL, which connects to the bubbles created in the landing zone. The entire procedure was performed using intraoperative optical coherence tomography (OCT). Once the two incisions were connected using blunt-edged Mac Pherson forceps, the bubbles were released from the surgical plane. The programmed ICRS(s), 6 mm in diameter, are then placed in the corneal tunnel from the limbal incision with the aid of Sinskey forceps. Finally, when the ICRS is in place, the surgery is complete.

A new technique to implant intracorneal ring-segments from the perilimbal region: one-year prospective pilot study report

“…This feature fosters innovation by facilitating exploration of novel ICRS designs, including concatenated combinations of profiles within a single tunnel, as well as injectable or articulated segments. Furthermore, by circumventing disruption to the roof of the corneal tunnel, the distal ends of the implants are positioned farther away from the incision site, thereby reducing the likelihood of wound healing complications—an issue we have previously documented [ 12 ]. This aspect holds particular significance, as common complications often stem from the insertion zone of the ICRS, where corneal epithelial ingrowth may precipitate localized corneal melting and segment migration, potentially culminating in implant extrusion in select cases [ 23 , 24 , 25 ].…”

“…Likewise, this work highlights the role of the femtosecond laser in performing these tasks. Analyzing the possibilities that the femtosecond laser could offer, our team embarked on developing an experimental surgical approach for ICRS implantation aided by FSL technology, introducing the ByLimb technique in 2021 [ 12 ]. Notably, this technique involves creating the incision from a paralimbic region.…”