摘要
Background:To evaluate refractive outcome 24 months after Deep Anterior Lamellar Keratoplasty(DALK)in pediatric patients by comparing results achieved using mechanical trephine and femtosecond laser.Methods:Twenty eyes of 20 patients affected by keratoconus were evaluated.To perform big-bubble DALK,10 eyes(Group 1;mean age 11.2±2.2 years)were subjected to the Hessburg-Barron mechanical trephine and the remaining 10 eyes(Group 2;mean age 11.3±3.1 years)to a 150 kHz femtosecond laser that performed mushroom incisions.Preoperative thinnest point in the corneal thickness map and K readings were measured by the Sirius Scheimpflug camera.We also evaluated corrected distance visual acuity(CDVA)as logMAR value using spectacles,spherical equivalent and refractive astigmatism.Results:Mean preoperative thinnest point and pre-and post-operative K readings did not show significant difference(P>0.05)between the two groups.CDVA,spherical equivalent and refractive astigmatism were respectively,0.14±0.08 logMAR and 0.13±0.10 logMAR(P=0.8),−4.2±1.1 D and−2.8±1.2 D(P=0.03),4.4±2.0 D and 3.6±1.2 D(P=0.4)in Groups 1 and 2.All DALK procedures were uneventful.Conclusion:Our findings suggest that femtosecond laser compared to mechanical trephine could significantly reduce the spherical equivalent amount in pediatric big-bubble DALK.