Influence of endoscopic sinus surgery on voice quality

Twenty-one patients with documented chronic paranasal sinusitis and in need of endoscopic endonasal sinus surgery were subjected to voice analysis. Ta pe recordings of different sustained vowels were performed pre- and postope ratively. All voice samples were examined with a sound spectrographic analy sis system. Patients having known nasal obstruction detected by active ante rior rhinomanometry were excluded from further study. Analysis of pre- and postoperative spectrograms focused on changes in center frequency or bandwi dth of the first four formants, as well as variations in specific differenc es of the formant frequencies and amplitudes. The different subgroups of pa tients revealed a series of significant changes in the parameters studied. The vowels [a:] and [i:] showed inverse changes in measured values, while e valuation of the vowel [u:] was restricted due to artifactual scattering of individual values. In general, bandwidth diminished and energy peaks of fo rmants increased postoperatively. In 6 of 21 patients (approximately one-th ird of the cases), patients or other individuals detected perceptual change s of speech postoperatively. Based on our data, we recommend informing all patients, and voice professionals in particular, about the possible effects of endonasal sinus surgery on altering speech.