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An “All-laser” Endothelial Transplant
Published on: July 6, 2015
Zig Zag versus Top Hat configuration in IntraLase-enabled penetrating keratoplasty
Raneen Shehadeh Mashor1, Irit Bahar2, Dan B Rootman3
1Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ontario, Canada Departfment of Ophthalmology, Bnai Zion Medical Center, Technion, Haifa, Israel.
Aim:
To compare the outcomes with IntraLase-enabled keratoplasty using (IEK) Top Hat (TH) versus Zig Zag (ZZ) configuration.
Methods:
Retrospective comparative series of 24 eyes that underwent TH and 10 eyes that underwent ZZ IEK.
Results:
There were no significant differences in LogMar Best-spectacle corrected visual acuity (TH- IEK=0.3; ZZ-IEK=0.18, p=0.18), spherical equivalent (TH-IEK=-3.55±3.7 dioptres (D); ZZ-IEK=-2.69±4.85 D, p=0.60), manifest cylinder (TH- IEK=3.79±2.43 D; ZZ- IEK=4.61±3.29 D, p=0.45), topographic astigmatism (TH-IEK=3.67±2.34 D; ZZ-IEK=4.26±1.1 D, p=0.63), total higher-order aberrations (TH- IEK=8.26±3.53; ZZ-IEK=8.1±4.71, P=0.92), endothelial cell density change from baseline (TH- IEK= -41.55%±15.86; ZZ-IEK=-25.45%±30.66, p=0.22) or time to suture removal in months (TH- IEK=7.48±4.07; ZZ- IEK=6.93±2.71, p=0.75). There was no difference in requirements for astigmatic keratectomy (TH-IEK=54.2%±13; ZZ-IEK=50%±5, OR=1.18) or complications (TH-IEK=25%±6; ZZ-IEK=30%±3, OR=0.78).
Conclusions:
TH-IEK and ZZ-IEK have comparable visual and refractive outcomes, wound healing and endothelial cell counts at 1-year.
