[Acoustic analysis in patients with trauma to unilateral cricoarytenoid joint by computer technique]

To investigate the acoustic characteristics of unilateral cricoarytenoid joint trauma and evaluate the effect of acoustic analysis technique on the diagnosis and treatment of this disease.

The voice signals of sustained vowel [a] were measured using a micro-computer with Dr. Speech software in 50 healthy adults and 30 patients with unilateral cricoarytenoid joint trauma. The acoustic parameters (jitter, shimmer and NNE) and spectrographic characteristics (harmonic waves, formants and noise) were analyzed. The acoustic changes before and after the treatment of arytenoid motion were observed and compared.

All acoustic parameters were significantly increased in trauma of unilateral cricoarytenoid joint. The pathologic spectrograph showed decrease or loss of harmonic waves and formants, and increase of noise, in middle and high frequencies. There was a relationship between NNE and the position of the vocal cord. After the treatment of arytenoid motion, 33% patients were cured and had normal acoustic parameters and spectrograph. 47% were improved with reduced parameters and improved spectrograph. The acoustics in 20% cases didn't change at all after treatment. The acoustic parameters were significantly decreased after the treatment of arytenoid motion.

The present study suggested that the acoustic parameters may estimating the degrees of voice lesion as objective standards and NNE may judge the degree of glottic closure. Both acoustic parameters and spectrograph are of value in the diagnosis, treatment effect and prognosis observation to cricoarytenoid joint trauma.