To compare the outcomes of mechanical and femtosecond laser– assisted tunnel creation for intrastromal corneal ring segment (ICRS) implantation in keratoconus.

In this prospective study, consecutive eyes with keratoconus were randomly assigned to have ICRS tunnel creation with a mechanical device or a femtosecond laser. Keraring ICRS with a 5.0 mm diameter and different arc length were implanted. The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, and keratometry (K) readings were measured preoperatively and 3&6 months and then 1 year postoperatively, finally data in the mechanical group and the femtosecond group were compared statistically.

One year postoperatively, there was significant improvement in UDVA, CDVA, K readings, spherical equivalent (SE), and manifest sphere and cylinder in both groups (P<.05). The mean reduction in maximum keratometry was 6.38 diopters (D) and 7.04 D, respectively, and the mean reduction in SE was 4.17D and 5.47D, respectively. There was no statistically significant difference between the 2 groups in visual or refractive results (P>.05). Bacterial keratitis, superficial segment placement, and segment extrusion in 1 eye, and white sterile deposition in 5 eyes occurred in the mechanical group.

Despite more intraoperative complications occurring in the mechanical group, the visual and refractive outcomes were similar to those in the femtosecond assisted tunnel creation group.