A comparison between manual and automatic flow inverse filtering for patients with spindle-shaped glottis during phonation

Abstract

Twenty-eight patients showing spindle-shaped glottal insufficiency with or without sulcus vocalis at laryngoscopic examination were examined with videostroboscopy, flow inverse filtering and audio recordings of voice. Inverse filtering was performed both manually and with an automatic method. No major differences were found between the inverse filtering methods regarding glottal flow or estimations of glottal closure and voice quality from flow data. Several flow parameters correlated well with perceived breathiness in the voice. The sulcus patients had significantly higher flow open quotient (OQ 20%), higher mean flow and higher fundamental frequency during phonation than the non-sulcus patients. Male sulcus patients also had higher estimated minimum area values than the male non-sulcus patients. The presence (or absence) of a hump in the closed phase of the glottograms was related to the presence (or absence) of a mucosal wave for the patients studied.

Key Words:

• inverse filtering
• spindle-shaped glottis
• sulcus vocalis