Augenabteilung am St. Franziskus Hospital Münster
The Role of the Epithelial Flap
in EPI-LASIK and LASEK
Suphi TaneriTravel Grant from B&L
ASCRS Symposium, April 2-8, 2009, San FranciscoASCRS Symposium, April 2-8, 2009, San Francisco
Augenabteilung am St. Franziskus Hospital MünsterAugenabteilung am St. Franziskus Hospital Münster
PurposePurpose• To evaluate the safety and predictability of
EPI-LASIK using an EPI Separator head coupled to the Zyoptix XP microkeratome
• To elucidate the influence of the epithelial flap in EPI-LASIK and LASEK on visual recovery and pain perception.
Augenabteilung am St. Franziskus Hospital MünsterAugenabteilung am St. Franziskus Hospital Münster
MethodsMethods• Ongoing prospective single-center study
comparing 14 eyes of 7 patients treated with EPI-LASIK using the XP EPI Separator (Bausch & Lomb, Rochester, New York) to a control group of 14 eyes of 7 patients treated with LASEK.
• Each epithelial flap was clinically evaluated by its dimensions and completeness of epithelial separation.
• After laser ablation, epithelial flaps of one eye per patient were repositioned and the other one discarded. All eyes received a soft contact lens.
Augenabteilung am St. Franziskus Hospital MünsterAugenabteilung am St. Franziskus Hospital Münster
MethodsMethodsBaseline:
EPI-LASIK
Age (Years)
Corneal Thickness (µm)
Sphere (D)
Cylinder (D)
SE (D) BCVA
average Keratometry(D)
Mean 29 550 -3.81 -0.67 -4.14 0.93 43.9SD 5 46 1.50 0.48 1.58 0.10 0.8Min 20 497 -1.50 -1.50 -6.63 0.7 42.6Max 40 611 -6.25 0.0 -1.63 1.0 45.9
LASEKAge (Years)
Corneal Thicknes (µm)
Sphere (D)
Cylinder (D)
SE (D) BCVA
average Keratometry (D)
Mean 34 530 -3.61 -0.43 -3.82 0.9 44.3
SD 4 25 1.42 0.44 1.57 0.13 1.7
Min 20 494 -1.75 -1.50 -5.88 0.7 41.6
Max 50 588 -5.75 -0.25 -2.0 1.0 47.0
Augenabteilung am St. Franziskus Hospital MünsterAugenabteilung am St. Franziskus Hospital Münster
ResultsResultsHE stain of a discarded epithelial flap
magnification 200x
Microscopical examination showed complete epithelial separation
Augenabteilung am St. Franziskus Hospital MünsterAugenabteilung am St. Franziskus Hospital Münster
ResultsResultsPAS stain of a discarded epithelial flapmagnification 200x
Microscopical examination showed complete epithelial separation
Augenabteilung am St. Franziskus Hospital MünsterAugenabteilung am St. Franziskus Hospital Münster
Results: Visual recoveryResults: Visual recovery
Mean uncorrected visual acuity was slightly better in LASEK in the abscene of an epithelial flap.In Epi-LASIK mean uncorrected visual acuity was better if the flap had been repositioned (not significant).
Augenabteilung am St. Franziskus Hospital MünsterAugenabteilung am St. Franziskus Hospital Münster
Results: Development of pain perceptionResults: Development of pain perception
Pain scores decreased continually from day 1 to day 4 in all groups and showed no significant difference between the 4 groups.
Augenabteilung am St. Franziskus Hospital MünsterAugenabteilung am St. Franziskus Hospital Münster
Results: Closing of the epitheliumResults: Closing of the epithelium
closed
Augenabteilung am St. Franziskus Hospital MünsterAugenabteilung am St. Franziskus Hospital Münster
Results: Haze and Epithelial Results: Haze and Epithelial OpacificationOpacification
• Epithelial opacification was slightly higher with repositioned flaps (Fantes scale).
LASEK Mean RangeFlap repositioned 0.43 ± 0.53 0-1Flap discarded 0.33 ± 0.52 0-1Epi-LASIKFlap repositioned 0.75 ± 0.27 0.5-1.0Flap discarded 0.33 ± 0.41 0-1.0
Augenabteilung am St. Franziskus Hospital MünsterAugenabteilung am St. Franziskus Hospital Münster
ConclusionConclusionInitial results indicate a safe and standardized fashion of performing a surface ablation using the Zyoptix XP Epi Separator.
The role of the epithelial flap in surface ablation seems negligible in the first 3 months.
Differences in late on-set haze formation may exist.