A 19-year-old man presented with a 3-year history of episodic headaches, right hemiparesis, and progressive vision loss in both eyes. Initially, extensive laboratory testing was unrevealing. MRI later demonstrated progressive enlargement and enhancement of the left optic nerve poorly correlated with the timing of his clinical manifestations. There was no clinical or radiological response to treatment with corticosteroids, mycophenolate mofetil, or rituximab administered empirically for possible inflammatory processes. Later in the disease course, he developed diabetes insipidus (DI), worsening vision to light perception bilaterally, severe cognitive decline, and spastic quadriparesis. Cerebrospinal fluid (CSF) beta human chorionic gonadotropin (β-hCG) was elevated. Eventually, a left optic nerve biopsy was performed, which was consistent with an intracranial pure germinoma with infiltration of the optic nerve and disseminated leptomeningeal disease. Although rare, intracranial germ cell tumors can primarily involve the anterior visual pathways and should be considered in the setting of DI and elevated CSF β-hCG.

中文翻译：

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颅内纯净生殖细胞瘤伴有视神经浸润。

一名19岁的男子有3年的发作性头痛，右偏瘫和双眼进行性视力丧失的病史。最初，尚未进行广泛的实验室测试。MRI随后显示左视神经的进行性扩大和增强与他的临床表现的时间差相关。对于可能的炎症过程，经验性给予皮质类固醇，霉酚酸酯或利妥昔单抗治疗均无临床或放射学反应。在病程的后期，他患上了尿崩症（DI），双眼视力恶化，双眼轻视，严重的认知能力下降和痉挛性四肢瘫痪。脑脊液（CSF）β人绒毛膜促性腺激素（β-hCG）升高。最终，进行了左视神经活检，这与颅内纯种生殖瘤伴视神经浸润和播散性软脑膜病一致。尽管罕见，但颅内生殖细胞肿瘤可能主要涉及前视觉通路，因此在DI和CSFβ-hCG升高的情况下应予以考虑。