Radiofrequency volumetric reduction of the tongue. A porcine pilot study for the treatment of obstructive sleep apnea syndrome.

STUDY OBJECTIVE: To investigate, in an animal model, the feasibility of radiofrequency (RF) volumetric tongue reduction for the future purpose of determining its clinical applications in obstructive sleep apnea syndrome (OSAS). DESIGN: The study was performed in three stages, one in vitro bovine stage and two in vivo porcine stages. The last stage was a prospective investigation with histologic and volumetric analyses to establish outcomes. SETTING: Laboratory and operating room of veterinary research center. PARTICIPANTS: A homogeneous population of porcine animal models, including seven in stage 2 and 12 in stage 3. INTERVENTION: RF energy was delivered by a custom-fabricated needle electrode and RF generator to the tongue tissue of both the in vitro and in vivo models. MEASUREMENTS AND RESULTS: Microultransonic crystals were used to measure three-dimensional changes (volumetric reduction). Lesion size correlated well with increasing RF energy delivery (Sperman correlation coefficient of 0.986; p = 0.0003). Histologic assessments done serially over time (1 h through 3 weeks) showed a well-circumscribed lesion with a normal healing progression and no peripheral damage to nerves. Volumetric analysis documented a very mild initial edematous response that promptly tapered at 24 h. At 10 days after RF, a 26.3% volume reduction was documented at the treatment site (circumscribed by the microultrasonic crystals). CONCLUSION: RF, in a porcine animal model, can safely reduce tongue volume in a precise and controlled manner. Further studies will validate the use of RF in the treatment of OSAS.

Tongue base reduction with hyoepiglottoplasty: a treatment for severe obstructive sleep apnea.

OBJECTIVE: To describe a surgical procedure for the treatment of severe obstructive sleep apnea syndrome (OSAS), the procedure's indications, and its results. STUDY DESIGN: A retrospective study of 10 male patients with OSAS treated by tongue base reduction with hyoepiglottoplasty (TBRHE) at the Foch Hospital (Suresnes, France) between 1994 and 1997. Patients had a mean body mass index (BMI) of 32 kg/m2, a mean respiratory disturbance index (RDI) of 70 events/h, and a mean minimal oxygen saturation of 78%. They had refused positive airway pressure therapy or wished to discontinue it. METHODS: Subtotal tongue base reduction preceded by lingual neurovascular bundle identification and derouting, epiglottal verticalization, mouth floor horizontalization, and hyoid bone repositioning was performed, associated in some cases to uvulopalatopharyngoplasty (UPPP). Indications were based on a site-related obstruction, on the absence of craniofacial deficiencies, and on the presence of hyolingual abnormalities determined by cephalometry and magnetic resonance imaging. RESULTS: TBRHE associated to UPPP in most cases had an 80% success rate, based on a postoperative RDI below 20 events/h and a reduction of the preoperative RDI of more than 50%. Snoring and excessive daytime sleepiness decreased or disappeared, respectively, in 100% and 90% of the cases. No neurovascular complications occurred. CONCLUSION: TBRHE is a safe procedure for the neurovascular bundle. Associated to a pharyngotomy, it is an effective treatment for severe OSAS attributable to tongue base obstruction. These results require confirmation in a larger series of patients.

[Tongue base reduction with hyoid-epiglottoplasty. A surgical alternative in severe sleep apnea syndromes]. / Basiglossectomie avec hyo-épiglottoplastie. Une alternative chirurgicale pour les syndromes d'apnées du sommeil sévères.

We present preliminary results and indications of tongue base reduction with hyo-epiglottoplasty for the treatment of severe obstructive sleep apnea syndrome (OSAS) due to isolated hyolingual abnormalities. The procedure consists in a subtotal resection of the tongue base after identification and derouting of the lingual neurovascular bundle. Hypopharyngeal enlargement, epiglottis verticalization, floor of the mouth tension and hyoid bone repositioning are also performed during the procedure. 14 severe OSAS male patients (mean apnea-hypopnea index of 71) were treated in our institution from November 1992 to February 1996. Indications were determined after a cephalometric analysis and a magnetic resonance imaging evaluation. Results were evaluated on clinical and polysomnographic criteria. No neurovascular complications occurred. Clinical results were excellent but success rate based on polysomnography was 50%. These preliminary results led us to change some of the steps in the technique. We also identified a predictive factor of success on the cephalometrics: an oropharyngeal area greater than 25 cm2.