In vivo performance of the Nitinol shape-memory stapes prosthesis during hearing restoration surgery in otosclerosis: a first report.

The limitations of manual prosthesis crimping in hearing restoration surgery for otosclerosis are thought to have a key role in the occurrence of incomplete postoperative elimination of conductive hearing loss and postoperative recurrences of conductive hearing loss. To eliminate manual crimping, the self-crimping, shape-memory alloy Nitinol stapes piston was introduced in nine otosclerosis patients. The results were compared with those in a database of surgeries performed with conventional titanium pistons. The effects of the self-crimping Nitinol prosthesis on the postoperative elimination of conductive hearing loss and its postoperative variations were investigated. The variations of postoperative residual conductive hearing loss were significantly smaller and the extent of conductive hearing-loss elimination greater in the Nitinol group. The mean postoperative residual conductive hearing loss was smaller in the Nitinol group. The postoperative stability of conductive hearing loss elimination was similar in both patient groups. Preliminary results suggest that the self-crimping shape-memory alloy Nitinol stapes piston overcomes the drawbacks of manual crimping in hearing restoration surgery for otosclerosis.