[Experimental study of contraction loss effects of mouth mucosa by ethanol injection]

We began treating patients with simple snoring and obstructive sleep apnea syndrome (OSAS) with the coblator radiofrequency generator in our outpatient clinic from April 2001. Good clinical results have been obtained, but we noticed a contractile effect on mucosa from ethanol, which possesses marked sclerotic degenerative action on tissue as well as radiofrequency energy. We conducted a series of experiments in a guinea pig model to investigate the efficacy of local ethanol injection in contracting mouth mucosa. To examine the influence on respiration of liquid injection, physiological saline was gradually injected in decrements into the arch of the palate mucosa. We found that the safe dosage that did not bring about edema and subsequent dyspnea was under 10 microliters. Based on this finding, ethanol in concentrations of 50%, 70%, and 100% at volumes of 1, 2, 4, 8, and 10 microliters was injected into the arch of the palate mucosa in guinea pigs and changes in local field mucosa were observed daily. In the 50% ethanol injection, no clear contractile effect on mucosa could be observed at any dosage. In contrast, the 100% ethanol injection led to strong tissue impairment that caused extensive necrotic collapse of the local field mucosa, even when the dosage was down to the minimum of 1 microliter. We found that, injection of 70% ethanol at 1 or 2 microliters, however, resulted in formation of a local field mucosa wound of lesser degree that healed completely within a few days, associated with moderate contraction of mucosal tissue. We concluded that in moderate dosage, 70% ethanol seems to have the potential for the treatment of endermosis, such as uvuloptosia (elongated uvula) and hypertrophy of palate mucosa, as a useful mucosa contractile agent.