The Orientation Of The Semicircular Canals In The Guinea Pig

Abstract

In 10 adult guinea pigs the stereotaxic coordinates of a series of points along each osseous semicircular canal were analysed to yield an equation of that canal plane in stereotaxic space. Angular relationships among the canal planes and between the canal planes and the major stereotaxic planes are presented together with the optimal positions of the head for physiological stimulation of each canal or pair of synergistic canals. The planes of the semicircular canals in each labyrinth are not perpendicular to one another and the planes of contralateral synergistic canals depart from parallelism by about 30d`.

This research was supported by grants from the National Health and Medical Research Council of Australia, Sydney University Research grants, and US Public Health Service grant NS 06658. Computing assistance was obtained from the Health Sciences Computing Facility, UCLA, sponsored by NIH Special Resources Grant RR-3.