Same Day vs. Sequential CK+CXL in the Treatment of Ectasia

Abstract

Purpose : Corneal crosslinking (CXL) is often combined with procedures to improve vision and corneal shape in patients with advanced ectasia; however, studies combining conductive keratoplasty (CK) with CXL have demonstrated marked regression by 3 months. We performed a non-randomized, prospective, non-comparative case series to evaluate Logmar improvement in vision using CK followed by same day CXL compared to CK 1 day before CXL in patients with ectasia. The goal of our study is to find a sustainable method for stabilizing the cornea and ultimately improve vision in patients with advanced ectasia.

Methods : Our study includes 209 eyes from 149 patients, 65% are male and 35% female. The mean age is 34 years. 17% of eyes were treated for post LASIK ectasia and 81% for keratoconus. Exclusion criteria includes corneal apex thickness less than 325 microns, rigid contact lens use within 4 weeks of CK and postoperatively, and patients with adequate corrected distance visual acuity (CDVA). CK was performed using intraoperative keratometry and/or serial Pentacam tomography measurements; CXL, using a novel, proprietary riboflavin loading system was performed the same day or 1 day following CK. CDVA was analyzed preoperatively and at postop month (POM)1, 2-4.5, 4.5-10, 10-15 using 2-tailed paired Ttest.

Results : For all patients at POM10-15, mean improvement in LogMAR UDVA is 0.083 (p=0.132) and LogMAR CDVA is 0.106 (p=0.001). Mean improvements in LogMAR CDVA is 0.08(p=0.03) at POM10-15 for same day eyes, 0.16 (p=0.01) at POM10-15 for eyes with CXL 1 day after CK. For patients with a preop CDVA of 20/40 or worse, mean improvements in LogMAR CDVA is 0.17 (p=0.02) at POM10-15 for CK followed by same day CXL and 0.41(p<0.001) at POM10-15 for eyes with CXL 1day after CK.

Conclusions : CK plus proprietary Epi-On CXL for ectasia is a safe, effective, non-invasive method to improve vision in select patients. Statistically significant improvement in CDVA is noted up to 15 months postop. Improvement in uncorrected distance visual acuity (UDVA) is noted, but is not statically significant at POM10-15. Superior improvement in vision is observed with CXL 1day after CK compared to eyes with same day CK and CXL. These results are more pronounced at 10-15 months, as there was markedly more regression in patients with same day CK + CXL by 10-15 months postoperatively. As expected, greater results are visible in patients with a preoperative CDVA of 20/40 or worse.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.