Supplemental Material for: Orbital schwannomatosis –two interesting cases

<p dir="ltr">Introduction:</p><p dir="ltr">Orbital schwannomas are a rare subtype of peripheral nerve sheath tumors that occur in cranial and peripheral nerves throughout the body.Their location in the orbit accounts for only 1%-4% of all head and neck tumors.Indolent growth delays diagnosis till pressure effects on the delicate neuro-ophthalmic structures within the bony orbit appear. Complete surgical excision is the preferred treatment modality.</p><p dir="ltr">Case reports:</p><p dir="ltr">Our two cases shared the typical clinical picture of long-standing progressive proptosis.

However, the intraoperative finding of two discrete, well-encapsulated schwannomas in the same orbit is highly unusual. In both patients, removal of the first lesion did not fully relieve the mass effect, prompting further exploration that revealed a second lesion. Histologically, both lesions were identical, showing the classic biphasic spindle cell pattern with strong S100 positivity.