Flap quality in single versus multiple use of the same blade in the Flapmaker microkeratome

We evaluated experimentally the variability of cut thickness, flap diameter, and cut quality produced by the Flapmaker corneal microkeratome (IOLTech), with single and repeated use of the same cutting blade.

Keratectomy was performed with twelve cutting heads (8.5-mm diameter, 160-microm cutting depth) on 47 corneas and with six cutting heads (8.0-mm diameter, 180-microm cutting depth) on 18 freshly enucleated swine eyes in a repeated manner. Ultrasonic pachymetry was determined at the initial, central, and final microkeratome pass zones, first before the flap was created and subsequently after the flap was reflected. Flap diameter was measured by planimetry. After the procedure stromal portions were submitted for scanning electron microscopy.

On the first blade use, mean central flap thickness was 145 +/- 32 microm and mean vertical flap diameter was 8.4 +/- 0.26 mm with the 8.5-mm blades. With the 8.0-mm blades, mean central flap thickness was 155 +/- 23 microm and mean vertical flap diameter was 8.0 +/- 0.27 mm. Scanning electron microscopy disclosed smooth cut surfaces when new blades were used, but with repeated blade use, increasingly prominent stromal bed folds were observed.

The evaluated blades produced reproducible flap size and thickness and good cut quality with single use, but after the first use, cut quality markedly deteriorated. Repeated use of Flapmaker cutting blades is not recommended.