Applications of Diode Laser in Stapes Surgery

Purpose of the study. The aim of our study was to estimate the efficacy and safety of high-power short-pulse mode 0.98 µm diode laser stapedoplasty based on the functional results.
Material and methods. Patients with tympanic otosclerosis (n=20) underwent laser stapedoplasty under local anesthesia using Teflon piston prosthesis. A diode laser with a wavelength of 0.98 µm was used in a contact shortpulse mode at a high output power (30 W 30 ms). Before the surgical intervention, the laser light guide was prepared by activation on a wooden spatula (5 pulses) to create carbon particles at the end that well absorb laser radiation with a wavelength of 0.98 µm. Number of pulses for perforating the stapes footplate was 2–3 impulses. To assess the possible damage of the inner ear and the functional results of the intervention, we performed audiometric test on the 7th day, after 1, 3, and 6 months. In addition, to assess the state of the inner ear during surgery, an assessment of vestibular reactions was carried out – a sense of falling, short-term dizziness (up to 10 seconds), long-term dizziness (more than 10 seconds), as well as an assessment of the nystagmus.
Results. Improvement of hearing thresholds for air conduction (AC) and closure of the bone-air gap (ABG) were obtained in patients in the postoperative period. Median values of hearing thresholds for AC: before surgery – 25±11.1 dB, after 1 month – 16.2 dB (Me), after 3 months – 15 dB (Me), and after 6 months – 15 dB (Me). When assessing hearing thresholds by AC (PTA) before and after the intervention, a statistically significant difference in the direction of decreasing the thresholds (p<0.05) was obtained using the paired Student’s t test. After 6 months, ABG closure of less than 20 dB was observed in all patients (100%), less than 15 dB – in 18 patients (90%) at frequencies of 0.5–4,0 kHz. In the postoperative period, no vestibular disorders and no increase in bone conduction (BC) hearing thresholds at high frequencies were observed, which indicates the absence of damage to the inner ear. Conclusion. Piston stapedoplasty using a diode laser with a wavelength of 0.98 µm allows achieving “excellent” (ABG≤10 dB) functional results in 80% of patients with otosclerosis 6 months after surgery. Intraoperatively and in the early postoperative period, the patients did not demonstrate vestibular disorders or a significant decrease in hearing thresholds at high frequencies, which indicates the safety of the proposed technique. Key words: laser stapedoplasty, piston stapedoplasty, otosclerosis, 980 nm diode laser, conductive hearing loss
Conflict of interest. The authors declare no conflict of interest.
Funding. There was no funding for this study