Comparison of manual and femtosecond astigmatic keratotomy in the treatment of postkeratoplasty astigmatism.

PURPOSE To compare the outcomes of femtosecond astigmatic keratotomy (FSAK) and manual astigmatic keratotomy (AK) in treatment of postkeratoplasty astigmatism. METHODS A retrospective, comparative, pairwise-matched case series including 150 patients who underwent either FSAK (n = 75) or manual AK (n = 75) for the treatment of astigmatism (>3.00 D) following penetrating keratoplasty or deep anterior lamellar keratoplasty. Pairwise matching for baseline variables (age, visual acuity and astigmatism) was performed. RESULTS Mean age was 57.5 ± 16.0 years. The FSAK group had significantly better postoperative best-corrected visual acuity (BCVA) (p = 0.010), uncorrected visual acuity (UCVA) (p = 0.049), corneal astigmatism (p = 0.020) and manifest astigmatism (p < 0.001) compared with the manual AK group. Gain of ≥3 lines in BCVA (logMAR) was seen in five eyes (6.7%) and 21 eyes (28.0%) in manual AK and FSAK, respectively (p = 0.005). Alpins vector analysis showed lower (closer to 0) index of success (0.50 ± 0.24 and 0.79 ± 0.48, p < 0.001) and higher (closer to 1) correction index (0.94 ± 0.45 and 0.74 ± 0.55, p = 0.020) in FSAK compared with manual AK. Corneal and manifest astigmatism improved significantly in both groups, while BCVA and UCVA improved significantly in FSAK only. Repeat AK rate was 32% (24 eyes) in manual AK and 4% (three eyes) in FSAK (p < 0.001). Overcorrection-related re-suturing rate was 0% in manual AK and 8% (six eyes) in FSAK (p = 0.037). There was one microperforation (1.3%) in FSAK, and there were no occurrences of graft dehiscence, infectious keratitis or graft rejection. CONCLUSIONS Both manual AK and FSAK were safe and effective in reducing postkeratoplasty astigmatism. FSAK had superior visual and keratometric outcomes compared with manual AK.