A videofluorographic and impedance curve study of swallowing *
Videofluoroscopy is considered to be the most accurate method for assessing oropharyngeal functions, swallowing physiology, or food as it is being swallowed, but it is an invasive radiographic technique. A number of non-imaging instrumentation procedures have been used to investigate various aspects of swallowing physiology including surface electromyography, electroglottography, and oropharyngeal manometry. The use of electroglottography, an impedance analysis of swallowing difficulty around the thyroid cartilage area, has been reported sporadically. I considered more information for impedance analysis must be available around the angles of the mandible. Using an electrical impedance technique and videofluoroscopy, the effects of voluntary movements, bolus, and aging were studied. Fortyseven normal volunteers were divided into two groups, a young adult group (23.0±2.0years) and an elderly group (71.4±6.5years). For impedance measurements, I used an electric impedance meter that was made for this study. Simulaneously, videofluoroscopy was carried out and impedance waves were recorded . The waveforms of the pharyngeal phase were unaffected by tongue movements but were influenced by laryngeal movements. The young age group had simple impedance waveforms, whereas the old group showed the presence of early flowing into the pharynx or separated swallowing on videofluoroscopy , and delayed pharyngeal transit times. Polyphasic impedance waves appeared in most of the old individuals. Since pharyngeal transit times show a tendency to elongate, further wave analysis of the neck impedance technique may reveal details of latent dysphagic patients at the bedside. As a therapeutic tool, this procedure could prove useful in providing biofeedback for improving swallowing parameters, (Accepted on October 28, 1997) Kawasaki Igakkaishi 23(3) : 165-173. 1997
