A single 210-degree arc length intrastromal corneal ring implantation for the management of pellucid marginal corneal degeneration.

PURPOSE: To determine the visual and refractive outcomes of 210-degree arc length intrastromal corneal ring segment (ICRS) implantation in eyes with pellucid marginal corneal degeneration (PMCD).

DESIGN

Retrospective, consecutive case series.

METHODS

Sixteen consecutive eyes of 10 patients who underwent a single 210-degree ICRS implantation by femtosecond laser for the management of PMCD and completed at least 1 year follow-up were included. A complete ophthalmic examination was performed preoperatively and postoperatively, including uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), manifest spherical and cylindrical refractions, spherical equivalent, and keratometric readings.

RESULTS

The mean follow-up period was 30.7 months (range 12 to 36 months). No intraoperative complication was observed. White deposits around the segments were noted in 2 of 16 eyes (12.5%) at the first postoperative year. The mean UCVA showed significant improvement, from 1.69 +/- 1.02 logarithm of the minimal angle of resolution (logMAR) preoperatively to 0.64 +/- 0.43 logMAR at the 36th month (n = 11, P < .001). The mean preoperative BSCVA was 0.88 +/- 0.68 logMAR; after 36 months, this improved to 0.35 +/- 0.34 (P < .001). At the 36th month, UCVA was improved in all eyes (n = 11, range: gain of 1 to 6 lines), whereas BSCVA was improved in 9 eyes (81.8%, range: gain of 2 to 7 lines) and remained unchanged in 2 eyes (18.1%); UCVA was 20/40 or better in 3 eyes (27%) and BSCVA was 20/40 or better in 8 eyes (72.7%). There was a significant reduction in the spherical equivalent refractive error, from -4.40 +/- 1.85 diopters (D) preoperatively to -1.86 +/- 0.60 D (P < .001), and the mean maximum keratometric power decreased from 49.70 +/- 4.32 D to 46.08 +/- 2.84 D (P < .001) after 36 months. The mean cylindrical refraction decreased from -4.39 +/- 1.86 D preoperatively to -2.38 +/- 1.35 D at 36 months (P < .001).

CONCLUSION

A single 210-degree arc length ICRS implantation using a femtosecond laser for patients with PMCD provides good visual and refractive outcomes.