investigations

Last reviewed 04/2022

A minimal series of investigations in hydrocephalus includes:

  • skull X ray:
    • assess skull size, suture diastasis; may be obvious in infants
    • look for evidence of chronic raised pressure - erosion of the posterior clinoids
    • look for associated defects - e.g. basilar invagination

  • CT scan including contrast - reveals pattern of ventricular enlargement and, frequently, the site and cause of obstruction:
    • generalised dilatation - suggests communicating hydrocephalus
    • lateral and 3rd ventricles dilated:
      • 4th ventricle normal - suggests aqueduct stenosis
      • 4th ventricle absent or deviated - suggests a posterior fossa mass

  • ultrasonography through the anterior fontanelle in infants - demonstrates ventricular enlargement but is less informative than CT