Microdrill, CO2-laser, and piezoelectric stapedotomy: a comparative study.

OBJECTIVE: To compare 3 different devices used to perforate the stapes footplate in otosclerotic patients.

STUDY DESIGN: The study design was a prospective unblinded study. It was conducted at the ENT Department of a general hospital.

MATERIALS AND METHODS: Ninety subjects undergoing primary stapedotomy for otosclerosis by a senior surgeon participated. A stapedotomy operation was performed under local anesthesia with reversed sequence of surgical steps. Three different devices were used to perforate the posterior half of the footplate: a microdrill (MD), a CO2 laser (CO2), and a Piezosurgery bone device (PZS). The hole diameter was 0.7 mm. Three consecutive samples of unselected patients were recruited. All patients of each sample were operated with the same device. Main outcome measures were preoperative and postoperative air- (AC) and bone-conduction (BC) audiometry, intraoperative findings, and postoperative complications. Postoperative pure-tone audiometry was done 1 month after surgery.

RESULTS: The CO2 laser was used in 30 stapedotomies, the PZS in 30, and the MD was used in 30. Bone-conduction pure-tone averages did not worsen in the MD and CO2 groups. CO2 laser shows a trend toward less residual air-bone gap and more functional gain at low frequencies. Piezosurgery bone device patients lost approximately 10 dB in BC at 4,000 Hz. Significant differences in AC thresholds gain and in the residual air-bone gap were found between groups. Piezosurgery bone device patients had less gain and more residual gap at high frequencies as a result of a slight deterioration of BC threshold. A higher rate of postoperative vertigo was also found in PZS patients.

CONCLUSION: The use of the CO2 laser seems associated with the best functional results, although on a statistical basis, they do not differ significantly from that obtained with the standard MD platinotomy. The PZS stapedotomy is effective from a surgical point of view for most patients. However, it is associated with a slight but significant deterioration of BC at high frequency and at higher vertigo rate. More basic validation of the stimulation parameters is necessary for safe use of this new technology.