Synchronized videostroboscopic and electroglottographic examination of glottal opening.

Interpretation of electroglottography (EGG) as an index of glottal contact area has been complicated by difficulty obtaining independent validation measures. The purpose of this research was to implement a new simultaneous EGG/videostroboscopic technique for the evaluation of the relationship between a discontinuity in the opening phase of the EGG waveform with the onset of glottal opening viewed via videostroboscopy. The results support previous suggestions that this EGG discontinuity, when observed in nonpathologic individuals, usually marks the onset of glottal opening along the superior surface of the vocal folds.