Abstract
Myofibrous organization of 20 adult humans (12 males, 8 females, aged from 29 to 88, average 61.7 years) was studied to identify functional characteristics of m, oblicularis oculi in man. Materials were embedded in celloidin and stained with hematoxylin and eosin. The following results were obtained: 1) Cross-sectional area of the inferior part was larger than that of the superior part, and this tendency was remarkable in males. 2) The number of muscle fibers per sq. mm of the superior tended to be larger than that of the inferior, and no sex difference was observed. 3) The total number of muscle fibers of the inferior exceeded to that of the superior, and those of males exceeded those of females. 4) The muscle fiber size of the inferior was larger than that of the superior. Those of males tended to be larger than those of females. 5) The muscle fiber size of m. oblicularis oculi was smaller than that of other human muscles. Muscle fiber density of the inferior was greater than that of the superior, and those of males were greater than those of females. 6) Correlation between the cross-sectional area and the number of muscle fiber per sq. mm was negative in the superior part and positive in the inferior. There was positive correlation between the cross-sectional area and the total number of muscle fibers in both parts, and no correlation between cross-sectional area and muscle fiber size.
