Histologic and physiologic effects of electrocautery, CO₂ laser, and radiofrequency injury in the porcine soft palate

Objectives: This study was undertaken to compare the effects of electrosurgery, CO₂ laser, and radiofrequency on the histological structure and physiological properties of the soft palate. These surgical techniques are used for stiffening and reducing the soft palate in the treatment of snoring and mild sleep apnea. Study Design: Fifteen pigs were divided into five groups. Methods: group 1 underwent electrosurgery incision of the lateral soft palate and excision of the uvula. Group 2 underwent the same procedure with the CO₂ laser. Group 3 underwent CO₂ laser ablation of the midline soft palate mucosa. Group 4 underwent radiofrequency volumetric reduction. Group 5 served as control. After 5 weeks the animals were sacrificed. Soft palate mucosa and muscle were subjected to tensiometric and histological analysis. Statistical analysis of tensiometric measurements was done with an ANOVA using a Bonferroni-Dunn correction. Results: Tensiometric measurements of the mucosa were increased over normal controls when the surgical technique resulted in mucosal disruption. When the surgical technique resulted in primarily muscle disruption (radiofrequency) tensiometric measurements of the muscle were increased over controls. Histological analysis demonstrated normal remucosalization in all specimens, with fibrosis increased at the site of the primary injury. Conclusions: The type of injury produced resulted in identifiable patterns of physiological and histological change. Understanding of the effects of available surgical techniques is important in guiding our choice of surgical approach and allows us to better counsel our patients on their surgical options.