Rare retro-orbital intraconal occurrence of benign schwannoma - a case report

Abstract

Schwannomas otherwise referred to as neurilemmomas are benign, slowly progressing, encapsulated tumors arising from Schwann cells in the peripheral nerve sheath. They may grow along any peripheral or cranial nerve. Amongst the cranial nerve schwannomas, the eigth cranial nerve is the commonest site. But orbit is a rare site for their occurrence. Solitary orbital schwannomas account for 1% of orbital neoplasms. Orbital schwannomas arise from 3(th), 4(th), 6(th) cranial nerves and ciliary ganglion. Since complications like optic nerve compression and atrophy are likely to occur, early diagnosis is imperative for appropriate management. The present case deals with the rare occurrence of a retro-orbital, intraconal schwannoma in a 23-year-old lady who was clinically and radiologically diagnosed to have a retro-orbital cavernous hemangioma. The variable presentation and location of this tumor can certainly make the diagnosis difficult which may be confirmed only by histopathological examination as in the present case. Our patient underwent a successful complete surgical excision before any complications could ensue.

Keywords: Intraconal; Retro-orbital; Schwannoma.

[Table/Fig-1]:

Clinical picture of the 23-year-old female patient with proptosis of right eye

[Table/Fig-2]:

CT showing left eye with intraconal hyperintense lesion

[Table/Fig-3]:

Well encapsulated tumor measuring 2.5 X 2 cms

[Table/Fig-4]:

Cut section- completely encapsulated, gray-white, glistening with focal hemorrhagic areas

[Table/Fig-5]:

Hypercellular (Antoni-A) areas and Hypocellular (Antoni-B) areas

[Table/Fig-6]:

H&E, 40X : Spindled tumor cells with bland oval to wavy nuclei with buckling