Topography-guided vertical implantation of intacs using a femtosecond laser for the treatment of keratoconus

We report 2 cases of vertical implantation of Intacs (Addition Technology) for the correction of keratoconus with temporal cones. Case 1 was a 16-year-old boy. In the left eye, the refraction was -4.50 x 100, with an uncorrected visual acuity (UCVA) of 0.5 and a best corrected visual acuity (BCVA) of 0.7. The flattest meridian (K1) was 43.7@100 and the steepest meridian (K2),46.9@10. Case 2 was a 20-year-old woman. In the left eye, the refraction was -6.00 -7.00 x 100, with a UCVA of 0.05 and a BCVA of 0.1; K1 was 51.3@25 and K2, 55.1@115. In each patient, 2 Intacs segments of 0.45 mm and 0.25 mm were inserted in the temporal and nasal regions, respectively. One year postoperatively, the UCVA was 0.7 and 0.3 in Case 1 and Case 2, respectively, and the BCVA was 0.8 and 0.5, respectively. The postoperative refraction was -2.50 x 110 in Case 1 and -5.25 x 95 in Case 2. Based on the localization of the cone, Intacs implantation appeared to improve visual acuity in keratoconic patients.