title: Computed tomography and pathological findings of five nasal neurilemmomas.
abstract: OBJECTIVE
  Neurilemmomas are benign tumors deriving from Schwann cells of the nerve sheath. They occur in all parts of the body. The highest incidence of neurilemmoma is in the head and neck region (38-45%), but involvement of the nose and paranasal sinus is quite rare, with only sporadic cases having been reported in the world literature. Fewer than 4% of these tumors involve the nasal cavity and paranasal sinuses. We describe the clinical, pathologic, and computed tomography (CT) features of five nasal neurilemmomas.
  
  
  METHODS
  CT features of five patients with nasal schwannoma proved by operation and pathology were investigated.
  
  
  RESULTS
  Schwannomas tend to be solitary and are usually well-circumscribed tumors with an oval, round or fusiform shape in the unilateral nasal cavity. The lesions usually have a mottled central lucency with peripheral intensification on contrast-enhanced CT scans. The heterogeneous appearance is related to areas of increased vascularity with adjacent non-enhancing cystic or necrotic regions.
  
  
  CONCLUSIONS
  Schwannoma should be considered in the differential of unusual nasal masses. Certain clinical and CT patterns may be of use in the differential diagnosis.
authors.affiliation: Department of Otolaryngology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China. zhouyunzhoush@163.com.
authors.forename: Jing
authors.initials: J
authors.lastname: Hu
authors.forename: Yang-Yang
authors.initials: YY
authors.lastname: Bao
authors.forename: Ke-Jia
authors.initials: KJ
authors.lastname: Cheng
authors.forename: Shui-Hong
authors.initials: SH
authors.lastname: Zhou
authors.forename: Ling-Xiang
authors.initials: LX
authors.lastname: Ruan
authors.forename: Zhou-Jun
authors.initials: ZJ
authors.lastname: Zheng
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009442:Neurilemmoma / Q000000981:diagnostic imaging* / Q000473:pathology*; D009669:Nose Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D012583:Schwann Cells / Q000473:pathology; D014057:Tomography, X-Ray Computed / Q000379:methods