To determine the refractive and keratometric predictability,stability,efficacy and complication rate of Femtosecond laser Astigmatic keratotomy for post PKP and DALK astigmatism in Keratoconus

The Femtec(20/10 perfect vision,Gmbh Heidelberg,Germany)Femtosecond Laser performed Paired 90-degree angled arcuate incisions on the graft button at 1.00mm inside the graft edge and at 85%of the corresponding local graft thickness,whereas the angular lengths of the cuts were determined by analyzing the locations of the steepest meridians in the refraction ,javal and computeric keratometry and topographic map.main outcome measures included preoperative and postoperative manifest refraction, uncorrected visual acuity(UCVA),best spectacle-corrected visual acuity(BSCVA),surgically induced astigmatism(SIA) ,pentacam corneal topography and full pachymetric results,javal and computeric keratometric astigmatism and complications.

Postoperative follow-up extended to 6 months.mean uncorrected logarithm of the minimum angle of resolution(logMAR)BSCVA and UCVA improved from preoperative values of0.30±0.18and0.85±0.32 to6-month values of0.19±0.17(standard deviation)and0.65±0.33,respectively(P˂0.05)mean subjective astigmatism was7.79±2.64diopters(D)preoperatively and3.69±2.25at6month after surgery(p˂0.05)surgically induced astigmatism was8.65±5.15D.mean subjective sphere changed from-0.85±4.35D preoperatively to -2.41±4.79D postoperatively(p˂0.05)

Femtolaser assisted astigmatic keratotomy is an effective treatment for high astigmatism after PKP and DALK in keratoconus patients with an encouraging refractive predictability.there is some myopic shift after femtolaser assisted astigmatic keratotomy. Further and larger studies are needed to achieve reduction of cylinder with greater accuracy