2026-06-30T01:25:16Zhttps://docta.ucm.es/rest/oai/request

oai:docta.ucm.es:20.500.14352/1092062024-10-30T15:54:28Zcom_20.500.14352_14col_20.500.14352_15

00925njm 22002777a 4500 dc Cho, Kwang Ho author Jin, Zhe Wu author Umeki, Shinichi author Yamamoto, Masahito author Murakami, Gen author Abe, Shinichi author Rodríguez Vázquez, José Francisco author 2021-08-21 Purpose: To compare fetal and adult morphologies of the orbital muscle (OM) and to describe the detailed topographical anatomy in adults. Methods: Using unilateral orbits from 15 near-term fetuses and 21 elderly cadavers, semiserial horizontal or sagittal paraffin sections were prepared at intervals of 20-100 µm. In addition to routine histology, we performed immunohistochemistry for smooth muscle actin. Results: At near term, the OM consistently extended widely from the zygomatic bone or the greater wing of the sphenoid to the maxilla or ethmoid. Thus, it was a large sheet covering the future inferior orbital fissure. In contrast, the adult OM was a thin and small muscle bundle connecting (1) the greater wing of the sphenoid to the maxilla (11/19 cadavers), (2) the lesser wing of the sphenoid to the maxilla (5/19) or the greater wing (3/19). The small OM was likely to be restricted within the greater wing (5/19 cadavers) or the maxilla (3/19). Two of these five types of OM coexisted in eight orbits. OM attachment to the lesser wing was not seen in fetuses, whereas ethmoid attachment was absent in adults. Conclusions: The lesser wing attachment of the OM seemed to establish after birth. A growing common origin of the three recti was likely involved in "stealing" the near-term OM attachment from the ethmoid. The strong immunoreactivity of remnant-like OM in the elderly suggests that OM contraction is still likely to occur against the increased flow through a thin vein. However, the contraction might have no clinical significance. Cho KH, Jin ZW, Umeki S, Yamamoto M, Murakami G, Abe SI, Rodríguez-Vázquez JF. Human orbital muscle in adult cadavers and near-term fetuses: its bony attachments and individual variation identified by immunohistochemistry. Surg Radiol Anat. 2021 Nov;43(11):1813-1821. doi: 10.1007/s00276-021-02819-1 0930-1038 10.1007/s00276-021-02819-1 https://hdl.handle.net/20.500.14352/109206 1279-8517 https://doi.org/10.1007/s00276-021-02819-1 34417852 https://link.springer.com/article/10.1007/s00276-021-02819-1 Human orbital muscle in adult cadavers and near-term fetuses: its bony attachments and individual variation identified by immunohistochemistry