Oral cavity obliteration is a novel predictor of functional outcomes after glossectomy reconstruction

Objectives: The primary goal for reconstruction of oral tongue defects is to improve speech and swallowing. The purpose of this study is to present a new reconstructive metric that uses volume displacement to measure oral cavity obliteration and correlate this metric to outcomes of speech and swallowing.

Methods: 47 patients underwent resection and primary closure or free-tissue reconstruction of oral tongue defects. Oral cavity obliteration was measured using a novel oral volume assessment test (OVAT). Briefly, a latex balloon filled with pudding was placed on the patient's tongue and patients performed mouth closure to expel the pudding. Residual volumes represented dead space in the oral cavity and was measured by water displacement. These results were correlated with the Speech and Swallowing Assessment and Assessment of Intelligibility of Dysarthric Speech (AIDS) instruments.

Results: The mean residual volume was 7.4 cc (range 3 - 20 cc; sd 4.5 cc). There was a correlation with lower residual volumes (better obliteration) with increasing AIDS efficiency ratio (R = 0.72, p < 0.001). A receiver operator curve was used to identify 10 cc of residual volume as the optimal cutoff point. Binary logistic regression using this cut point showed that residual volume significantly predicts normal nutritional mode (p < 0.001), ability to tolerate all liquids (p = 0.007), range of solids (p = 0.004), eating in public (p = 0.007), understandability (p < 0.001), and speaking in public (p = 0.01).

Conclusions: Oral volume assessment test (OVAT) is a novel measure of residual volume (obliteration) that correlates with improved speech efficiency, intelligibility, speaking in public and swallowing outcomes.