Lenticule Interface Quality After Ocular Surface Washout And Tear Homogenization Versus No Washout Before Femtosecond Laser Docking In Klex Surgery: Assessment Using Automated Image Analysis
Published 2026 - 44th Congress of the ESCRS
Reference: FP11.05 | Type: Free paper | DOI: 10.82333/t00z-0j28
Authors: Prof. Dr Shady Awwad* 1 , Dr Karen Asfar 2 , Dr Hady Yazbeck 3 , Dr Jad F. Assaf 4
1Ophthalmology,American University of Beirut,Beirut,Lebanon, 2Ophthalmology,Baylor,Houston,United States, 3Ophthalmology,OHSU,Portland,United States, 4Ophthalmology,OHSU,Houston,United States
Purpose
To evaluate the value of ocular surface washout and tear homogenization before femtosecond laser docking in KLEx surgery.
Setting
American University of Beirut Medical Center
Methods
116 eyes of 71 patients who underwent KLEx using the Ziemer LDV Z8 were retrospectively analyzed. 1:1 matching was used to form clinically comparable eye pairs: before and after adoption of ocular surface washout by the operating surgeon. Baseline and postoperative evaluations were performed at day 1, week 1, and months 1 and 3, and included UDVA, CDVA, refraction, corneal topography, higher-order aberrations, and optical coherence tomography. Image analysis algorithm to evaluate the homogeneity score (HS) of an image was applied on retroillumination images generated by a pyramidal aberrometer (PERAMIS/OSIRIS) to quantify interface quality. Correlations between HS and clinical and tomographic and aberrometric parameters were assessed.
Results
At day 1, HS decreased from 0.83±0.01 to 0.74±0.04 and 0.82±0.02 to 0.77±0.03 for the standard and new technique, respectively (both P < 0.001). 63.8% vs 75.8% of eyes achieved UDVA ≥ 20/20 at day 1 in the standard and new groups, respectively, with mean UDVA improving from 1.06±0.22 to 0.09±0.17 and 1.05±0.28 to 0.01±0.09 (both P < 0.001). The new technique yielded superior HS at day 1 and week 1 (P=0.007 and P<0.001) and superior day 1 ∆CDVA compared to the old technique (P=0.011). 35.4% in the standard group and 47.8% in the new group gained ≥1 line of CDVA. Overall, ∆HS correlated with early gain in ∆CDVA at day 1 and week 1 (r = -0.40; P=0.0017 and r= -0.31; P=0.0126, respectively). Visual results were comparable at 3 months.
Conclusions
Ocular surface washout prior to femtosecond laser docking in KLEx surgery provides a faster early visual recovery and a better lenticule interface homogeneity than standard technique. The Homogeneity Score provides an objective measure of lenticule interface quality after KLEx and can help guide treatment modifications.