3 Month Outcomes Of Corneal Allogeneic Intrastromal Ring Segments For Corneal Ectasia.
Published 2026 - 44th Congress of the ESCRS
Reference: POCOR400 | Type: Free paper | DOI: 10.82333/2nz1-b576
Authors: Dr Sherif Tolees* 1 , Dr Alhosafy Abdulwahab 2
1Ophthalmology,Magrabi Health,Jeddah,Saudi Arabia, 2Ophthalmology,Gamal Abdulnasser Hospital,Alexandria,Egypt
Purpose
To evaluate 3-month changes in uncorrected and corrected distance visual acuity (UDVA/CDVA, logMAR) after single-segment CAIRS for corneal ectasia; to quantify refractive and optical quality effects (manifest cylinder, anterior HOAs, vertical coma); and to document early safety using a standardized femtosecond-guided workflow.
Setting
Magrabi Health, Almurjan Eye Center. Jeddah
Methods
Prospective consecutive case series of 7 eyes (6 male patients) with corneal ectasia (6 keratoconus; 1 post-LASIK ectasia). Two keratoconus eyes had prior CXL. All eyes received one KeraNatural allogeneic segment with femtosecond-laser tunnel creation (Wavelight ES200/FS200). Planning followed an Istanbul-style nomogram: inner diameter 4.0 mm, outer diameter 7.5 mm, tunnel depth 250 µm, channel width 1.75 mm, incision cut length 1.5 mm, energies 1.3 µJ (incision and ring), axis aligned to cone location. Primary outcomes were changes in UDVA and CDVA (logMAR) at 3 months; secondary outcomes included manifest refraction cylinder and optical quality metrics (anterior HOAs, vertical coma).
Results
UDVA improved from 0.61 ± 0.57 to 0.12 ± 0.06 logMAR (P < .001), and CDVA from 0.14 ± 0.15 to 0.03 ± 0.05 logMAR (P < .001). Manifest refraction showed MRSE −0.48 ± 1.79 D and cylinder −4.11 ± 1.35 D pre operatively, with cylinder improving to −2.75 ± 1.05 D at 3 months (P < .001). Maximum anterior HOA (4-mm pupil) decreased from 1.12 ± 0.26 µm to 0.88 ± 0.48 µm, and vertical coma from 0.85 ± 0.26 µm to 0.38 ± 0.09 µm. No major complications (infection, extrusion, or migration) were observed.
Conclusions
CAIRS using standardized femtosecond-guided tunnels and a single allogeneic segment produced clinically meaningful gains in visual acuity, reduced astigmatism, and improved optical quality by 3 months, with a favorable early safety profile. These findings support CAIRS as a viable addition to the ectasia management pathway; larger cohorts with longer follow-up are underway to validate refractive and tomographic stability and refine a personalized nomogram.