Cross-sectional area of scala tympani in human and cat.

The cross-sectional area of scala tympani is measured in midmodiolar sections of both human and cat temporal bones (20 pairs each). The areal sizes of scala tympani in different turns of human cochlea are more than twice those in the cat. A noticeable area reduction between the lower basal turn and the upper basal turn is found in the cat. The cross-sectional view of scala tympani is ovoid to round and flat on top in the basal turns, but it is more like a flat triangle in the lower middle turn and above. The area measurement of the scala tympani assists the development of the implantable electrode. The information also contributes to the construction of models for physiological experiments.