Orbital lymphatic vessels: immunohistochemical detection in the lacrimal gland, optic nerve, fat tissue, and extrinsic oculomotor muscles

ABSTRACT Purpose: To identify the lymphatic vessels in orbital specimens from human cadavers using light microscopy and immunohistochemical analysis. Methods: A postmortem study included 10 orbital specimens from 10 human cadavers. The orbital specimens were obtained no later than 12 hours after death. The orbital specimens were dissected into lacrimal gland, optic nerve, fat tissue, and oculomotor muscles. The histologic criteria to qualify as a lymphatic vessel were thin-walled channels of endothelium without a well-developed basal membrane and with an erythrocyte-free, irregular lumen. The immunohistochemical criteria were irregularly shaped, thin-walled vessels with an erythrocyte-free, irregular lumen and immunopositivity for podoplanin D2-40. Results: The lacrimal gland, optic nerve, fat tissue, and extraocular muscle sections were positively stained with podoplanin D2-40. Conclusions: This study demonstrated lymphatic vessels in the human orbit, more precisely, in the lacrimal gland, dura mater of the optic nerve, adipose tissue, and extrinsic oculomotor muscles via light microscopy and immunohistochemistry.

摘要
目的：采用光学显微镜与免疫组织化学分析，识别人类尸体眼眶标本中的淋巴管。
方法：本死后研究纳入10具人类尸体的10份眼眶标本，标本获取时间不晚于死后12小时。将眼眶标本解剖为泪腺、视神经、脂肪组织及眼外肌。淋巴管的组织学判定标准为：由内皮细胞构成的薄壁管道，无发育完善的基底膜，管腔无红细胞且形态不规则。免疫组织化学判定标准为：管腔无红细胞、形态不规则的薄壁血管，且呈podoplanin D2-40免疫阳性。
结果：泪腺、视神经、脂肪组织及眼外肌标本均呈podoplanin D2-40免疫阳性染色。
结论：本研究通过光学显微镜与免疫组织化学方法，证实人类眼眶组织（确切而言为泪腺、视神经硬脑膜、脂肪组织及眼外肌）中存在淋巴管。