Analysis of the articulation after glossectomy

Rehabilitation of the oral cancer patient should aim to achieve not only morphological restoration but also post-operative functions. However, there are few reports describing quantitative evaluation of the latter. The authors have attempted quantitative evaluation of post-operative articulatory function after glossectomy, and report the evaluation of it by speech intelligibility, electropalatography (EPG), and acoustical analysis. Subjects were five directly sutured patients and five patients reconstructed with forearm flap, all after glossectomy. The target syllable was /ta/ from among speech intelligibility test samples. The speech intelligibility and acoustical analysis were investigated pre-operation, and 1, 6 and 12 months post-operation. EPG data were collected by DP-01(RION) at 6 months post-operation. Acoustical analyses were carried out by consonant frequency characteristics and formant variance from consonant to vowel transitions. As a result, subjects reconstructed with a forearm flap showed higher restorative tendency than directly sutured subjects. Articulatory characteristics expected from acoustical analysis were more in agreement with the results of EPG than with the results of the speech intelligibility test. From the results, it was suggested that the acoustical analysis used for this research could reveal changes in articulatory movement and will be useful for quantitatively evaluating post-operative articulatory functions.