Laser-assisted myringoplasty--technical aspects

At lower power, lasers fuse collagen fibres and weld tissues. Welded collagen fibres make a solid bond and allow tissue growth along the bonded edges. Our aim was to study applicability of lasers in myringoplasty. We used a KTP-532 laser in outpatient myringoplasty. The laser beam was delivered through a micromanipulator connected to a microscope or through a 200-400-micron silica fibre. The perichondrium was used for transplantant and harvested from the tragus. The margins of the perforation in the eardrum were evaporated, with the laser operating in a continuous mode at 2-4 W. The middle ear was filled with gelfilm to provide support for the transplant. The perichondrium was placed under the margins of the tympanic membrane and lazed at low power (0.2-1.5 W) in continuous mode. In pale tissues, venous blood, methylene blue or fluorescein was used to enhance the tissue admittance of laser energy. Surgical failures were linked to thermal tissue damage due to excessive energy during lazing. In two cases, visibility via microscope into the anterior edge was not complete and the transplantant did not adhere in the relatively limited area. One patient had epidermal growth under the tympanic membrane and developed local cholesteatoma. Laser-assisted myringoplasty provides several advantages over traditional myringoplasty: it is minimally invasive, no manipulation of the ossicles is needed and it is convenient in anterior perforations, where it can be done endoscopically. We prefer a fibre delivery system to a micromanipulator, as lazing with endoscopes is possible and thermal damage is easier to prevent.