Comparison of manual and femtosecond laser arcuate keratotomy procedures for the correction of post-keratoplasty astigmatism

PURPOSE: To compare the effectiveness of femtosecond laser (FSL) assisted and manual arcuate keratotomy (AK) procedures for the correction of postkeratoplasty astigmatism. METHODS: Fifty-two eyes (52 patients) were treated with FSL assisted AK and 53 eyes (51 patients) with manual AK for post-keratoplasty astigmatism. The main outcome measures included preoperative and postoperative manifest refraction, uncorrected and corrected distance visual acuity (UDVA, CDVA), corneal topography and complications. RESULTS: In FSL group, UDVA changed significantly from 0.90 ± 0.43 preoperatively to 0.60 ± 0.39 at last follow-up (p = 0.001). In manual group, preop- (0.87 ± 0.35) and post-operative UDVA (0.93 ± 042) were comparable (p = 0.535). CDVA improved from 0.30 ± 0.18 preoperatively to 0.20 ± 0.14 at last follow-up visit in FSL group (0.014) and 0.28 ± 0.15 preoperative to 0.23 ± 0.19 at last postoperative visit (0.074) in manual group. Postoperative UDVA and CDVA were comparable between both the groups (p > 0.05). The mean preoperative refractive cylinder was 6.38 ± 3.73 and 7.15 ± 132, decreasing significantly to 5.06 ± 2.06 and 5.19 ± 2.25 after manual and FSL assisted AK procedures respectively. Mean change in the refractive cylinder was −1.10 ± 4.11 in manual AK group and −2.19 ± 2.35 in FSL group (p = 0.134). Perforation, overcorrection and regression occurred in respectively 3 eyes (5.8%), 12 eyes (23.07%) and 1 eye (1.92%) in FSL group and 1 eye (1.9%; macro-perforation), 7 eyes (13.21%) and 8 eyes (15.09%) in manual group. Additionally, in the manual group, severe ectasia occurred in 1 eye (1.9%). CONCLUSION: FSL assisted AK procedure is comparable or to a certain extent better regarding safety and efficacy than manual AK procedure. Postoperatively, FSL resulted in better outcomes of UCVA, BCVA, refractive cylinder and keratometric astigmatism compared to the manual AK procedures; although, the difference between the groups was not statistically significant.