Tuesday, October 16, 2012

Congenital Midline Nasofrontal Masses

Midline nasofrontal masses are due to faulty regression of the midface dural diverticulum during embryologic development. The differential diagnosis includes:

  • Epidermoid and dermoid cysts
    • dermoid  
      • ectoderm + skin appendages
      • usually midline and tend to occur at the glabella
    • epidermoid
      • ectoderm without skin appendages
      • usually paramidine
  • Nasal gliomas
    • not a neoplasm
    • cerebral heterotopia
    • can be intranasal (lateral nasal wall, middle turbinate, nasal septum) or extranasal (usually at glabella, +/- overlying skin telangectasia)
    • T1WI - isointense/hypointense to gray matter
    • T2WI - hyperintense to gray matter
  • Encephaloceles
    • herniation of intracranial content through a skull defect with a persistent connection to the subarachnoid space
    • high prevalence of associated intracranial abnormalities
      • intracranial cysts, callosal agenesis, interhemispheric lipomas, facial clefts, schizencephaly
    • usually isointense to gray matter on all MR sequences 
      • may be hyperintense on T2WI due to gliosis

Lowe LH, Booth TN, Joglar JM, et al. Midface anomalies in children. Radiographics 2000;20:907-22.

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.