Published online Feb 12, 2013. doi: 10.5318/wjo.v3.i1.1
Revised: December 21, 2012
Accepted: January 23, 2013
Published online: February 12, 2013
AIM: To reduce astigmatism, increase corneal volume and improve visual acuity.
METHODS: A retrospective, single-surgeon, single-center, clinic-based study of a surgical procedure on twenty-four eyes of fourteen patients diagnosed with stage III or stage IV keratoconus. Paired arcuate keratotomy coupled with modified circular keratotomy was performed at a single center by a single surgeon as an outpatient procedure with local anaesthetic in a minor surgery room. Modified circular keratotomy was performed 7 mm from the pupillary center with depth of incision ranging between 70% and 90% of corneal thickness. Arcuate keratotomy was performed 2.5 mm from the pupillary center with the depth of incision at 90% of corneal thickness. Angular length of the arcs ranged between 60° and 120° depending on the astigmatic power of the cornea.
RESULTS: Astigmatism decreased in 87.5% of the 24 treated eyes, increased in 8.33% and did not change in 4.17%. Corneal volume increased in 91.66% of the 24 eyes and decreased in 8.34%. Visual acuity improved in 100% of the eyes; there was a mean improvement of 59% from preoperative visual acuity, 8.34% of the treated eyes reaching a visual acuity of 1.0 (20/20) with correction. No complications occurred during or after surgery. No suturing was performed and there was no rupturing at incision sites. There was statistical significance difference between pre.sph against post.sph (P = 0.001). Also between pre.cyl against post.cyl (P = 0.005), there was no significance difference between pre.axis against post.axis (P = 0.05).
CONCLUSION: Paired arcuate keratotomy coupled with modified circular keratotomy should be considered as an intervention before performing keratoplasty.