Evaluation of corneal flap dimensions and cut quality using the SKBM automated microkeratome.
OBJECTIVE
To evaluate flap dimensions and cut quality with repeated blade use of the automated Summit Krumeich-Barraquer microkeratome (SKBM [LadarVision]).


METHODS
Department of Ophthalmology, University Erlangen-Nuremberg, Erlangen, Germany.


METHODS
The SKBM (160 microm plate, intended flap diameter 9.0 mm) was used to perform a corneal hinged flap in 35 pig cadaver eyes. Seven blades were reused 5 times each. The flap diameter was measured by planimetry, and the thickness was assessed by ultrasonic pachymetry. Scanning electron microscopy (SEM) of blades and stromal beds was performed.


RESULTS
With single use of the blade, the mean central flap thickness was 145 microm +/- 25 (SD). The vertical/horizontal flap diameter was 9.0 +/- 0.03 mm/8.6 +/- 0.03 mm. No thickness gradient was observed from the incision (138 +/- 31 microm) to the flap hinge (130 +/- 30 microm). If the blade was used more than 2 times, the flap was thinner at the incision (157 +/- 34 microm versus 124 +/- 20 microm; P =.003) and the hinge (143 +/- 24 microm versus 122 +/- 31 microm; P =.04), but the central thickness remained unchanged. With multiple use of the blade, SEM analysis showed increasing cut irregularity, more tissue remnants on the blade surface, and a progression in blade irregularities (up to 9.3 microm).


CONCLUSIONS
Reproducible flap size and thickness can be obtained with single use of stainless steel blades in the SKBM. With multiple use, the quality of the blades and the stromal bed deteriorates and the peripheral thickness of the flaps decreases. Thus, single use of blades is recommended.
Viestenz
Arne
A
Department of Ophthalmology, University of Erlangen-Nürnberg, Germany. Arne.Viestenz@t-online.de
Langenbucher
Achim
A
Hofmann-Rummelt
Carmen
C
Modis
Laszlo
L
Viestenz
Anja
A
Seitz
Berthold
B
D000818:Animals; D001837:Body Weights and Measures; D003319:Corneal Stroma / Q000601:surgery* / Q000648:ultrastructure*; D020731:Keratomileusis, Laser In Situ / Q000295:instrumentation*; D008855:Microscopy, Electron, Scanning; D015203:Reproducibility of Results; D013524:Surgical Flaps; D013552:Swine