A new microviscometer for determining the viscosity of middle ear effusion

A new microviscometer has been developed based on the capillary viscometer method. The device uses a glass sensor tube for aspirating 15-microliter samples. The relative viscosity of the samples was estimated from the negative pressure required for aspiration of the fluid. These pressures ranged widely from 1 centipoise (cp) to 10,000 cp. Measurement of the viscosity of middle ear effusions in 119 samples from 110 otitis media with effusion patients using this device revealed a close relation between their values and their gross appearance (serous less than seromucoid less than mucoid). The microviscometer is useful to determine the relative viscosity of a very small amount of fluid such as middle ear effusion.