Blades with blunt ledge (Descemet's membrane protection) are used to perform the superficial keratectasia (removal of superficial layers of corneal stroma). Used to remove the 4 parts of separated stromal layers after the "Big Bubble" procedure.
https://cdn.shopify.com/s/files/1/0605/8249/4420/files/Corneal_Procedures.pdf?v=1643297274,https://cdn.shopify.com/s/files/1/0512/1710/5045/files/RUMEX_Corneal.png?v=1612360271