EC Ophthalmology

Schwannomas are benign peripheral nerve sheath tumors arising from Schwann cells and represent a small proportion of orbital neoplasms. Their occurrence along the optic nerve is exceptionally rare, given the absence of Schwann cells within the nerve itself. The angiomatoid variant is even less frequent and is characterized by prominent vascular spaces and hemorrhagic components, features that may complicate radiologic interpretation. Although typically slow-growing, these tumors may lead to progressive visual impairment and exophthalmos secondary to compressive effects on the optic nerve and adjacent orbital structures. Imaging-particularly MRI-plays a fundamental role in identifying lesion characteristics, assessing optic canal involvement, and guiding surgical planning, while definitive diagnosis relies on histopathological confirmation.

We report the case of a 30-year-old woman presenting with progressive right-sided exophthalmos and visual loss. MRI demonstrated a well-defined, fusiform intraconal lesion centered on the optic canal, hyperintense on T2-weighted sequences and intensely enhancing following gadolinium, with internal susceptibility artifacts suggestive of microhemorrhages. Histopathology revealed a spindle cell proliferation with pronounced angiomatoid features, confirming an angiomatoid schwannoma.

This case underscores the importance of considering optic nerve schwannoma-even in its rare angiomatoid form-in the differential diagnosis of unilateral progressive exophthalmos with visual decline. Awareness of its imaging characteristics is essential for accurate diagnosis and appropriate treatment planning.

 Keywords: Optic Nerve Schwannoma; Angiomatoid Schwannoma; Orbital Tumor; Exophthalmos; MRI

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