Timing of swallowing events after single-modality treatment of head and neck carcinomas with radiotherapy

This paper reports the results of a preliminary study designed to evaluate swallowing function in 20 patients 1 year after successful treatment of hea d and neck carcinomas with radiotherapy. The timing of swallowing events wa s evaluated by videofluoroscopy. The mean values for each measure were comp ared to the normative data from 60 control subjects. The radiotherapy patie nts demonstrated prolonged pharyngeal bolus transit and a delay of laryngea l closure. Hyoid bone elevation began late relative to the onset of bolus m ovement. A strong trend toward a delay in hyoid elevation relative to bolus movement was demonstrated. The time required for the hyoid bone to reach m aximal elevation did not differ from that in normals, but the hyoid was hel d in an elevated position for a longer period of time. As a result of chang es in hyoid movement, the upper esophageal sphincter tended to open early r elative to the arrival of the bolus. In conclusion, changes in deglutition occur after radiotherapy, presumably as an adaptation to changes in tissue compliance.