Radiofrequency Volumetric Tissue Reduction of the Palate in Subjects With Sleep-Disordered Breathing: Outcome

28 May

Radiofrequency Volumetric Tissue Reduction of the Palate in Subjects With Sleep-Disordered Breathing: OutcomeWe had previously correlated RFe to lesion size in the porcine tongue model using 0.5 to 2.4 kj with a Spearman correlation coefficient of 0.986, which in the homogenous tissues of the tongue indicated that as energy increases so does lesion size. In the porcine evaluation, the lesion size was verified by gross and histologic sectioning. The palate tissues are not homogenous and are quite thin compared with the tongue tissues. Thus, any hint of blanching to the soft tissues and the extent of the edematous response was initially used to set the upper limits of RFe (Table 3). This empiric and clinical approach made it difficult to accurately assess whether the temperature at the surface in these initial treatments was in a range at, or below, what could safely be administered, and there was concern as to the lateral extent of tissue involvement. Digital infrared thermography was used to document these tissue thermal gradients, as well as the lateral spread of the lesion. This noninvasive technique quickly allowed conformation and adjustments to RFe parameters and the safe positioning of the active electrode, as well as substantiating that optimal temperatures were attained in the range of energy we were delivering. These data were used in conjunction with the clinical examination at 24 h and polysomnographic variables at 48 to 72 h. cialis professional

In this investigation, there were only statistically significant changes relating to safety in the polysomnographic variables of the RDI and nadir Sa02, and clinically at no time during treatment did there appear to be sufficient edema to compromise the airway, awake or asleep. The objective changes were of concern since there was a definite trend in the decrement of these variables. The RDI pretreatment in our group was a mean of 3.93±3.3, and at 48 to 72 h, it was 10.5±9.1, a 2.7-fold increase. The apnea index (AI) and hypopnea index (HI) were a pretreatment mean of 0.88±2.5, 3.05±2.5, and a posttreatment mean of 4.45±5.9, 6.01 ±4.4, respectively, which is a five-fold increase in AI and a 1.9-fold increase in the HI. (These data are similar to what was reported by Terris et al, in which postoperative edema following LAUP treatment for snorers was characterized. Following LAUP, the RDI and the AI increased four-fold. MRI scanning and video endoscopy demonstrated a decrease in the cross-sectional area of the upper airway at 48 to 72 h that was correlated clinically along with the objective sleep data.)