A new L-shaped titanium prosthesis for total reconstruction of the ossicular chain.

摘要

OBJECTIVE: To describe the technique used for total ossiculoplasty with the Fisch titanium total prosthesis and evaluate the 1-year postoperative functional results in patients presenting with the stapes (or footplate) without the malleus handle. STUDY DESIGN: Prospective trial with preoperative and postoperative comparison. SETTING: Academic and private practice tertiary care center for otologic surgery. PATIENTS: Forty-nine consecutive patients operated on from September 1996 to December 2000. SURGERY:: Staged ossicular reconstruction with a Fisch titanium total prosthesis placed between the footplate and the tympanic membrane without regard to the presence or absence of the stapes arch. Coupling of the prosthesis to the footplate was achieved by various techniques, including perforation, foot and spike on the footplate without perforation, and shaft alone (without foot) with tragal cartilage fixation (disc or small wedges). There was no interposition of cartilage between the prosthesis head and the tympanic membrane. MAIN OUTCOME MEASURES: Pre- and postoperative air and bone-conduction thresholds and air-bone gaps for pure-tone averages of three and four frequencies and for single frequencies. RESULTS: Postoperative air-bone gap closures within 20 dB distributed equally (50%) between 0.5, 1, and 4 kHz and reached the highest rate (89%) at 2 kHz (p < 0.05). The postoperative air-bone gaps for pure-tone averages reached 0 to 20 dB in 57% and 0 to 30 dB in 87% of the cases. There were no dead ears and no partial or total extrusions of prostheses. The best functional results were achieved through perforation coupling of the spiked foot to the footplate in large oval windows and after fixation of the shaft (without foot) with tragal cartilage disc in narrow oval windows. CONCLUSION: The functional results of the L-shaped Fisch titanium total prosthesis implanted in ears with the stapes but no malleus handle are best at 2 kHz and better than those of comparable columellar titanium prostheses over the remaining tested frequencies.