Orbital Dermoid

  • Etiology: developmental anomaly in which embryonic ectoderm is trapped in closing neural tube
  • Imaging: in upper outer quadrant at fronto-zygomatic suture, fat containing mass forming a fossa in adjacent bone, bony erosion common
  • Clinical: most common orbital mass
    — Epidermoids contain only ectoderm – specifically squamous epithelium
    — Dermoids contain only ectoderm – specifically squamous epithelium + hair + sebaceous/sweat glands

Cases of Orbital Dermoid