Eliminating the Limitations of Manual Crimping in Stapes Surgery? A Preliminary Trial with the Shape Memory Nitinol Stapes Piston

Abstract

Manual piston malcrimping in stapedotomy may be the major cause of the occurrence of the significant, interindividual variations of postoperative air-bone gap (ABG), air-bone gap closures (ABGC), and postoperative recurrences of conductive hearing loss. To eliminate the effects of manual crimping on stapedotomy outcomes, the self-crimping, shape memory alloy Nitinol stapes piston was investigated and hearing evaluated. Prospective, preliminary case-control study in a tertiary care referral center. Sixteen patients with otosclerosis undergoing reversed stapedotomy using the Nitinol stapes piston were matched to reference patients out of our conventional titanium piston database. The effects of the self-crimping Nitinol piston on the postoperative ABGC, the postoperative air-bone gap (ABG) variations, and the postoperative short-term hearing results were investigated 3, 6 and 9 months postoperatively. These data were statistically compared with the results of the control patients in our titanium stapes piston database. The mean postoperative ABG and the interindividual variations of the postoperative ABG were significantly smaller in the Nitinol group, the extent of ABGC greater in the Nitinol piston group, but not significant. The postoperative short-term stability of ABGC was similar in both groups. No infections or adverse reactions occurred during follow-up. Our preliminary results suggest that the self-crimping shape memory alloy Nitinol stapes piston eliminates the limitations of manual malcrimping in stapedotomy, thus optimising the surgical procedure. This allows reliable, safe, and consistent air-bone-gap closure in patients with otosclerosis up to 1 year after surgery.