Videofluoroscopic kinesiologic analysis of swallowing: defining a standard plane.

The Videofluorographic Swallowing Study (VFSS) has become the routine method for assessing swallowing dysfunction and accordingly, much research has been conducted on this procedure. However, due to a lack of standardization of the method of analysis of VFSS, it is often difficult to compare the results of such studies. Therefore, we conducted a comparative study of VFSS's spatial measurement using different standard planes used in the past study and Camper's plane and examined which plane was the most preferable.VFSS was performed on 20 healthy young volunteers (26.9 +/- 3 years) and 9 healthy elderly (77.3 +/- 3 years). Each subject swallowed 4ml of thin liquid barium. We measured hyoid displacement and opening of the upper esophageal sphincter (UES) by using four different standard planes.In the young group, the correlation between anterior hyoid displacement and UES opening was significant in all standard planes. In the elderly group, the correlation between anterior hyoid displacement and UES opening was significant only in Camper's plane. Moreover, this plane is hard to be affected by morphological change as ageing.Camper's plane was found to be as the most preferable plane for analyzing swallowing function.