Pediatric Arachnoid Cyst

  • Etiology:
  • Imaging: (radiograph, CXR, AXR, US, CT, MRI)
  • DDX:
  • Complications:
  • Treatment:
  • Clinical:

Radiology Cases of Arachnoid Cyst

MRI of hemispheric arachnoid cyst
Axial T2 (left) and coronal T1 (right) MRI without contrast of the brain show a large extra-axial cystic structure in the right hemisphere causing significant mass effect to the left.
CT of arachnoid cyst of the posterior fossa
Axial CT without contrast of the brain shows a cystic structure on the left side of the posterior fossa that is shifting the cerebellum, which is structurally normal, to the right. The fourth ventricle is compressed leading to a moderate amount of hydrocephalus.