Related Experiment Video
Updated: Jun 11, 2026
Three Different Protocols of Corneal Collagen Crosslinking in Keratoconus: Conventional, Accelerated and Iontophoresis
Published on: November 12, 2015
Sequential versus concurrent KERARINGS insertion and corneal collagen cross-linking for keratoconus
1Ophthalmology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt. telragal@hotmail.com
Purpose:
To evaluate the safety and efficacy of combined intracorneal ring segments (KERARINGS) insertion and corneal collagen cross-linking (CXL) performed in one session or two sessions and to present the refractive outcomes.
Setting:
Magrabi Eye Hospital, Cairo, Egypt.
Methods:
This prospective comparative study included 16 eyes of 10 patients with progressive mild to moderate keratoconus that were randomly divided into two groups. Group 1 included nine eyes that underwent KERARINGS insertion followed by CXL 6 montsh later; group 2 included seven eyes that underwent the two procedures at the same day. In both groups channel creation was performed using the femtosecond laser (Intralase FS 60).
Results:
There was statistically significant improvement in both groups' uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA), with significant reduction in refractive error and keratometric values (p<0.05). There was no statistically significant difference between both groups regarding the changes in UDVA, CDVA and refractive error (p>0.05). However, group 2 revealed more statistically significant reduction of keratometric values on topographical examination (p=0.046). The stromal haze that developed in both groups was more marked and persistent in group 2 than in group 1.
Conclusion:
Combined KERARINGS insertion and CXL can be performed safely in one or two sessions. However, the same-session procedure appears to be more effective regarding the improvement in the corneal shape.
