Two-Year Follow-up of Intracorneal Ring Segments Implantation in Adolescent Patients With Keratoconus.

PURPOSE: To evaluate the visual, refractive, topographic, and aberrometric outcomes after intracorneal ring segments (ICRS) implantation in adolescent patients with keratoconus.

METHODS

A retrospective longitudinal study was undertaken with a total of 61 eyes from 47 patients with keratoconus, aged between 13 and 18 years, implanted with a Ferrara-type ICRS. Topography (flattest keratometry, steepest keratometry, and asphericity), uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), refractive error (sphere and cylinder), and aberrometric measurements (spherical aberration and vertical coma) were evaluated before surgery and at 1 month, 6 months, 1 year, and 2 years after surgery.

RESULTS

UDVA exhibited a statistically significant increase at all times from 1 month to 2 years postoperatively (P < .001), whereas CDVA showed a statistically significant improvement at 1 month, 6 months, and 2 years (P < .002), but dropped in significance at 1 year postoperatively (P = .097). The refractive error analysis showed no variation in statistical significance in the sphere (P = .712) after 2 years. The cylinder presented a statistically significant decrease in diopters at all times from preoperatively to 2 years postoperatively (P < .007). Steepest keratometry manifested a statistically significant decrease in steepness at all times after surgery (P < .001), whereas flattest keratometry lost significance at 1 year (P = .298) and 2 years (P = .053) postoperatively. There was no statistically significant change in the spherical aberration at any of the measured times. The vertical coma was only significantly different at 2 years postoperatively (P = .001).

CONCLUSIONS

ICRS implantation is a safe and effective treatment for improving visual and corneal morphological parameters as shown at 2 years of follow-up in adolescent patients with keratoconus. It is a good option to flatten and regularize the cornea and to temporarily improve the quality of life of young patients and delay the need for keratoplasty. [J Refract Surg. 2021;37(2):91-97.].