Coblation lesion formation in a porcine tongue model.

OBJECTIVE To investigate, in a porcine tongue model, the lesions created by coblation to define the optimal application of this method in treating the enlarged tongue base in patients with obstructive sleep apnea syndrome. STUDY DESIGN A prospective, experimental animal study. SETTING Military medical center. SUBJECTS AND METHODS Fifteen fresh porcine tongue specimens were injected with normal saline, and a single coblation probe was applied to the tongue specimens to create multiple submucosal lesions at specific energy settings. Control lesions were created without the use of saline injections. After creating the lesions, the porcine tongue specimens were sectioned and examined grossly. Size and character of lesions were recorded for each of the specimens and were compared across energy settings. RESULTS The energy applied at each setting was calculated on the basis of watts multiplied by treatment time. Coblation with saline injection created visible lesions with an average lesion area of 1.20 to 2.87 cm(2). The average lesion area increased as setting increased. Without saline injection, the average lesion area was 0.15 to 0.8 cm(2). CONCLUSION The porcine tongue model describes the relationship between lesion size and cold ablation device settings. Setting, but not time, significantly affects lesion size. The coblation setting and treatment time directly impact the amount of energy delivered. Additionally, submucosal normal saline injection significantly increases lesion size at all settings and application times. Given the average lesion diameter described in this study, placing lesions 1 cm apart will optimize the area affected by coblation while minimizing lesion overlap.