PURPOSE: To investigate the effectiveness of femtosecond laser-assisted intrastromal relaxing incisions for astigmatism management and establish laser treatment parameters. METHODS:Sixteen eyes of 16 patients had regular astigmatism after penetrating keratoplasty. All sutures had been removed and the refraction was stabilized. Paired arcuate intrastromal incisions were made 180° apart within the graft stroma with a femtosecond laser preserving the epithelium. Follow-up examinations were performed at 1 week, 2 weeks, 1 month, and 3 months. RESULTS:The logMAR corrected distance visual acuity (CDVA) improved from 0.50 ± 0.29 to 0.32 ± 0.23 (Snellen 20/63 to 20/40). Refractive and topographic anterior cylinders decreased from 6.8 ± 2.2 diopters (D) to 3.7 ± 1.7 D and from 9.5 ± 4.8 D to 4.4 ± 2.1 D, respectively. Stabilization of topographic cylinder was observed 1 month postoperatively. The worse the preoperative CDVA was and the higher the preoperative values for the refractive and topographic cylinders were, the higher the surgically induced changes were. Anterior side cut angles at 90° and 120° produced similar results. A bulge of incision occurred in one eye requiring compression sutures.CONCLUSIONS: Signifi cant improvement in CDVA and refractive and topographic cylinders indicated a good effect of femtosecond laser-assisted intrastromal relaxing incisions in reducing astigmatism. No advantage between 90° and 120° anterior side cut angles was found. No infections were recorded and no patient expressed discomfort.[J Refract Surg. 2013;29(6):378-382.] stigmatism occurring after penetrating keratoplasty is common and 4 to 5 diopters (D) of postoperative penetrating keratoplasty astigmatism is not unusual.1 Mild cases can be treated with spectacles or contact lenses. However, some patients with postoperative penetrating keratoplasty have more severe astigmatism that requires surgical treatment.2,3 Arcuate keratotomy is a surgical method to treat astigmatism and is traditionally made mechanically with a knife or keratome. [4][5][6][7][8][9][10][11][12] This causes the incised meridian to fl atten and steepen perpendicularly, thus reducing astigmatism. 13 The advantages of arcuate keratotomy are that it does not penetrate the anterior chamber, it preserves the optic axis, and it can be used to treat high astigmatism.The use of femtosecond lasers for relaxing incisions has been studied. [13][14][15][16][17][18][19][20][21][22] The therapeutic results of femtosecond laser-assisted incisions that penetrate the epithelium are similar compared to the mechanical incisions. [14][15][16][17][18][19][20] We studied the effect of intrastromal relaxing incisions made with a femtosecond laser. Theoretical advantages of intrastromal incisions where the corneal surface is not penetrated are a reduced risk for infection and reduced inconvenience caused by pain. PATIENTS AND METHODSAll patients were referred to Helsinki University Eye Hospital for treatment of postoperative penetrating keratoplasty astigmatism. They wer...

Efficacy of femtosecond laser-assisted intrastromal relaxing incisions is correlated with the posterior depth of the incisions. The deeper incisions were more effective.

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