Anteriority of Tongue Position After Glossectomy Surgery

Objectives: The study will measure anterior volume of the tongue in controls and patients who have had glossectomy surgery to remove cancer from the oral part of the tongue. The sound “s” is challenging for glossectomy patients, therefore the effect of “s,” and the easier sound “sh,” was studied on the vowel “uh” to see if its anteriority was related to the consonant. We expect patients to have less anteriority due to the loss of tongue tissue.

Methods: Using Cine-MRI, tongue volume was measured for the sound “uh” in the speech tasks “a shell” and “a souk”. Volume anterior to the maxillary 1^st molars (M1) and maxillary 2^nd premolars (PM2) was divided by the total tongue volume to determine the percent of anteriority using ITK SNAP software.

Results: In controls, there was no systematic relationship between anteriority of “uh” in “s” vs. “sh” context. In patients, the tongue was more anterior during the “uh” in “a shell” than “a souk.”

Conclusions: In patients, anteriority of “uh” is greater in “sh” because the body of the tongue is similar in shape between these two sounds. In the case of “s,” the tongue tip extends forward and if that also occurs during the “uh,” the missing tongue tissue will result in a smaller anterior volume.