Transoral Endoscopic Coblation Tongue Base Surgery in Obstructive Sleep Apnea: Resection versus Ablation

<b><i>Background:</i></b> A new transoral tongue base surgical procedure for the treatment of snoring and obstructive sleep apnea (OSA) is described. It is named “Robo-Cob” technique because it is similar to transoral robotic surgery (TORS) but it is performed by means of coblation technology in order to resect the tongue base in countries where TORS is not an available option for such benign conditions. <b><i>Methods:</i></b> In this prospective, randomized, controlled trial, the new Robo-Cob technique was carried out in 25 adult OSA patients with confirmed tongue base hypertrophy at preoperative drug-induced sedation endoscopy. The results of this procedure were compared with the coblation endoscopic lingual lightening (CELL) technique used to ablate (or minimally resect) the central part of the tongue base, in another 25 adult OSA patients with similar characteristics (age, sex, preoperative body mass index and Apnea-Hypopnea Index, AHI). The base of tongue surgery was part of multilevel surgery including also septoturbinoplasty and barbed reposition pharyngoplasty (with/without tonsillectomy). <b><i>Results:</i></b> In this study, the Robo-Cob technique is proved to be feasible and effective in all cases either alone or when combined with other procedures in multilevel surgical settings. No/minimal intraoperative or postoperative complications were observed. Postoperative pain as measured by visual analog scale ranged from 3 to 7. No tracheostomy was done in any patient. Objective clinical improvement was confirmed by a level 3 polygraphy performed 6 months after surgery. There was significant difference in operative time at the level of the tongue base between Robo-Cob and CELL techniques, with shorter times observed within the Robo-Cob group. Moreover, the Robo-Cob technique provided tongue base tissue specimens that allowed measurement of the volume that ranged from 5 to 17 cm³ (mean 11.64 ± 3.49 cm³). It was found that resection of at least 10 cm³ of tongue base tissue was associated with better outcomes in terms of postoperative AHI reduction. <b><i>Conclusion:</i></b> In this study, the added values of using coblation for resection and not ablation appear to be the short surgical time, the low postoperative tissue edema, and the possibility of providing tissue specimens to measure resected volumes.