Schwannoma of the Nose at the Keystone Area in Relation to the Dorsal Nasal Nerve

Abstract

Schwannomas are well-circumscribed, solitary benign encapsulated tumors arising from Schwann cells, which originate from neural crest cells. 1 They constitute only 4% of the head and neck tumors and involve the paranasal sinuses and nasal cavities. 2 About 80% of cases involve the vestibulocochlear nerve, followed by the trigeminal nerve in this region. 3 A 27-year-old woman presented to us with complaints of swelling over the nose for the past 8 months. She was medically managed for associated tension headaches. She gave no history of nasal obstruction, trauma, epistaxis, localized facial numbness, anosmia, or other swellings. Clinical examination showed a hemispherical, fi rm swelling of size 1.5 (cid:1) 1.0 (cid:1) 0.75cm over the rhinion and left keystone area in the subcutaneous plane, with side-to-side mobility and pinchable overlying skin. Deep palpation caused dyses-thesia at thetip of the nose.Anterior rhinoscopyexamination revealed no intranasal extension. High-de fi nition ultrasonography (HD-USG) imaging showed no cystic degeneration. Computed tomography (CT) scan revealed a hyperintense lesion over the rhinion and left keystone area of the nose, with no bony or cartilaginous erosions. Contrast magnetic resonance imaging (MRI) showed the same with delayed centripetal fi lling