Mechanical versus CO₂ laser occlusion of the posterior semicircular canal in humans

The purpose of this study was to compare the effectiveness of mechanical and laser-assisted posterior semicircular canal occlusion (PCO) for the treatment of intractable benign paroxysmal positional vertigo (BPPV). Twelve consecutive patients with intractable BPPV underwent PCO by three surgeons, six with mechanical PCO and six with CO₂ laser-assisted PCO. PCO eliminated positional vertigo in all patients treated with the laser and five of six patients treated without the laser. Dysequilibrium was present in all patients immediately postoperatively. This resolved in all patients treated with the CO₂ laser but in only two of six patients treated without the laser (p = 0.03). Patients were hospitalized for dysequilibrium for an average of 5.2 and 2.8 days for the mechanical and laser-assisted groups, respectively. Preoperative and postoperative hearing was not significantly different between the groups. No clinically significant postoperative hearing loss was encountered in either group. These results suggest that PCO is an effective treatment for intractable BPPV. The incidence of dysequilibrium that persists following PCO may be reduced by using the CO₂ laser to seal the membranous canal prior to occluding the bony canal.