Endoscopic multicolor investigation of swallowing.

Background: The complexity of the diagnostic/therapeutic problem in ENT-specific as well as in neurogenic dysphagia requires that test foods be offered in a variety of consistencies (viscosities), at different temperatures, and with various tastes. The swallowing assessment is undertaken with different head and trunk postures, using different swallowing techniques. Methods: A series of test foods of varied viscosities is prepared with different food colorings. It is given to the patient according to an individually tailored viscosity plan, but usually in the same (repeatable) color sequence of blue - yellow or blue - yellow - black, an order which offers optimal color contrasts. Results, Conclusions: During repeated swallowing assessments, the "multicolor technique" is more useful for endoscopic observation of the pharyngolaryngeal route of the food bolus than the "methylene blue swallow". Food coloring is cheap and it changes neither the taste nor the pH of the food.