Harvey Brianna M, Bhatnagar Kunwar P, Schenck Robert J, Rosenberger Alfred L, Rehorek Susan J, Burrows Anne M, DeLeon Valerie B, Smith Timothy D
School of Physical Therapy, Slippery Rock University, Slippery Rock, Pennsylvania, 16057.
Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, Kentucky.
Anat Rec (Hoboken). 2016 Dec;299(12):1690-1703. doi: 10.1002/ar.23468.
Living primates have relatively large eyes and support orbital tissues with a postorbital bar (POB) and/or septum. Some mammals with large eyes lack a POB, and presumably rely on soft tissues. Here, we examined the orbits of four species of strepsirrhine primates (Galagidae, Cheirogaleidae) and three species of fruit bats (Pteropodidae). Microdissection and light microscopy were employed to identify support structures of the orbit. In bats and primates, there are two layers of fascial sheets that border the eye laterally. The outer membrane is the most superficial layer of deep fascia, and has connections to the POB in primates. In fruit bats, which lacked a POB or analogous ligament, the deep fascia is reinforced by transverse ligaments. Bats and primates have a deeper membrane supporting the eye, identified as the periorbita (PA) based on the presence of elastic fibers and smooth muscle. The PA merges with periostea deep within the orbit, but has no periosteal attachment to the POB of primates. These findings demonstrate that relatively big eyes can be supported primarily with fibrous connective tissues as well as the PA, in absence of a POB or ligament. The well-developed smooth muscle component within the PA of fruit bats likely helps to protrude the eye, maintaining a more convergent eye orientation, with greater overlap of the visual fields. The possibility should be considered that early euprimates, and even stem primates that may have lacked a POB, also had more convergent eyes than indicated by osseous measurements of orbital orientation. Anat Rec, 299:1690-1703, 2016. © 2016 Wiley Periodicals, Inc.
现存的灵长类动物眼睛相对较大，眼眶组织由眶后棒（POB）和/或眶隔支撑。一些眼睛较大的哺乳动物没有眶后棒，可能依靠软组织。在此，我们研究了四种狐猴型灵长类动物（婴猴科、鼠狐猴科）和三种果蝠（狐蝠科）的眼眶。采用显微解剖和光学显微镜来识别眼眶的支撑结构。在蝙蝠和灵长类动物中，有两层筋膜片在眼睛外侧与眼周相连。外层膜是深筋膜的最表层，在灵长类动物中与眶后棒相连。在没有眶后棒或类似韧带的果蝠中，深筋膜由横向韧带加强。蝙蝠和灵长类动物有一层更深的膜支撑眼睛，根据弹性纤维和平滑肌的存在确定为眶周膜（PA）。眶周膜在眼眶深处与骨膜融合，但在灵长类动物中与眶后棒没有骨膜附着。这些发现表明，在没有眶后棒或韧带的情况下，相对较大的眼睛主要可以由纤维结缔组织以及眶周膜支撑。果蝠眶周膜内发达的平滑肌成分可能有助于突出眼睛，保持更会聚的眼睛方向，使视野有更大的重叠。应该考虑到这样一种可能性，即早期的真灵长类动物，甚至可能没有眶后棒的灵长类祖先，其眼睛的会聚程度也比根据眼眶方向的骨骼测量结果所显示的要高。《解剖学记录》，299:1690 - 1703，2016年。© 2016威利期刊公司。
