Observations of cochlear microcirculation using intravital microscopy.

The guinea pig cochlea was prepared for visual observation of blood vessels using fluorescence intravital microscopic techniques. Measurements were made of the lateral wall vessels in the third cochlear turn and of the basilar membrane and lateral wall vessels in the first turn. A stable and consistent pattern of flow was observed under a variety of manipulations, including blood pressures of less than 20 mmHg. The rationale for the choice of observation areas in the cochlea and the specific vessel types studied at these locations are discussed. The change in blood velocity in cochlear blood vessels during pentoxifylline perfusion and during exsanguination are described.