Computerized reconstruction of the regional blood flow in the rodent cochlea

The regional blood flow in the cochlea has been studied by mapping the distribution of microspheres in 22 micron thick serial sections of plastic embedded rat and rabbit cochleas. Using a computer-assisted reconstruction technique, a graphic display of the microspheres in each cochlea is obtained. From this display, microspheres may be counted and their distribution may be observed both in relation to the different vascular areas and with respect to the length of the cochlea. This technique, coupled with quantitation of the microspheres in a reference blood sample, offers a method for calculating total and regional cochlear blood flow using non-radioactive microspheres. In addition, this technique allows analysis of blood flow patterns with respect to the different capillary beds along the length of the cochlea. Thus it may be possible to determine if regional blood flow displays a longitudinal gradient, as do other functional, morphologic and biochemical characteristics of the cochlea.