Experimental Observation on the Superior Oblique Muscle Function in the Rabbits.

Park, Byung Il; Han, Hong Joo

Original Article

Journal of the Korean Ophthalmological Society 1976;17(2):137-142.
Published online February 1, 1976.

Experimental Observation on the Superior Oblique Muscle Function in the Rabbits.

Byung Il Park, Hong Joo Han

Department of Ophthalmology, Chonnam University Medical School, Kwangju, Korea.

가토상사근의 (家兎上斜筋) 기능에 관한 실험적연구

박병일 , 한홍주 ( Byung Il Park , Hong Joo Han )

Abstract

In anesthetized rabbits, the superior oblique muscle was excited by stimulation of a vestibular canal nerve. Induced reflex ocular movements were observed by the naked eyes, and were recorded by means of nystagmographic and oculographic techniques. Superior oblique muscle contraction induced by stimulation of a vestibular canal nerve produced ocular incycloduction associated with elevation. The elevatory action of superior oblique muscle was also demonstrated by means of the nystagmographic recording. Contraction of the superior oblique muscle caused augmented incycloduction in adduction of the eyeball, whereas excitation of the muscle produced augmented elevation in abduction of the eyeball. When these eye movements produced by the superior oblique muscle are compared to those of Tokumasu et al. observed in monkey and cat, the direction of the rotatory action appears to be contradictory. Such phenomenon may be ascribed to the anatomical differences of the oblique muscles in these animals endowed with the binocular or monocular vision.