| 摘要 |
In a blade ( 1 ) for cutting away an epithelial flap from a Bowman's membrane ( 31 ), the blade tip ( 11 ) is designed in such a way that, in the state in which the blade tip ( 11 ) is inserted between epithelium ( 2 ) and Bowman's membrane ( 31 ), said blade tip ( 11 ) spreads open a clearance space between the epithelium ( 2 ) and the Bowman's membrane ( 31 ). The clearance space thus held open results in a pre-tensioning of connections between the epithelium ( 2 ) and the Bowman's membrane ( 31 ). The cutting edge of the blade tip ( 11 ) is rounded and has a thickness which corresponds at least substantially to the thickness of the epithelium ( 2 ). The blade ( 1 ) is held removably in a blade holder ( 8 ) in such a way that the blade tip ( 11 ), in relation to the cutting plane ( 9 ), has an application clearance angle in a range of from 10° to 30°. Drive means ( 82, 83 ) of the blade holder ( 8 ) move the blade ( 1 ) in the advance direction ( 7 ) and set the cutting edge of the blade ( 1 ) in a lateral oscillating movement perpendicular to the advance direction ( 7 ) in the cutting plane ( 9 ), the advance travel being negligible compared to the cumulative lateral travel of the cutting edge resulting from the oscillation movement. As a result of the pre-tensioning and of the alternating load caused by the oscillating movement, the connection between the epithelium ( 2 ) and the Bowman's membrane ( 31 ) can be separated without forward pressure having to be exerted on the epithelial cells to do this, with the result that intercellular connections of the epithelium ( 2 ) are not impaired.
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