Purpose: To evaluate the results of the first 10 keratoconus patients submitted to Ferrara's ring surgery. Methods: In a prospective study, 10 keratoconus patients were included with best uncorrected visual acuity equal to or worse than 20/100, contact lens intolerance and absence of significant corneal scar. Patients were healthy otherwise, with no systemic medications or diseases. LogMAR visual acuity, refraction, topography and surgical complications were recorded. Minimum follow up was three months. Results: Two microperfurations occurred during the incision for the inferior tunnel. After surgery we had one case of single acrylic extrusion and four cases of displacement of one or both segments. Overall spectacle corrected visual acuity improved from 0.750 ± 0.374, to 0.438 ± 0.342 (p=0.026). The mean noncorrected visual acuity on the first day after surgery was 0.667 ± 0.447 (n=9), and final noncorrected visual acuity of 0.562 ± 0.272 was recorded. Five patients achieved spectacle corrected visual acuity of 0.5 LogMAR units was recorded or better, after three months of surgery. One patient did not show any significant flattening of the cornea at topography. Conclusion: This study showed improvement of visual acuity, refraction and topography in most patients in relation to preoperative results.
Keratoconus; Corneal stroma; Prostheses and implants; Visual acuity; Corneal topography; Prospective studies
