#foarads

Individuals with spina bifida and/or Chiari malformation may develop a syrinx (collection of fluid in the spinal cord). The mechanism is thought to be blockage of CSF flow in the subarachonid space at the level of the foramen magnum --> venous congestion --> spinal cord edema --> collection of fluid in the potential space at the center of the spinal cord (syringomelia) or off-center in the cord (hydromelia). Image comes from an anesthesiology paper, Anand, et alia, "Anesthetic management of a patient with syringomyelia and Arnold-Chiari malformation type I with autonomic dysfunction," Anaesth Pain & Intensive Care 2015;19(3):408-411.

A. This is a trick question, as no imaging is required to diagnose congenital hypothyroism; the diagnosis is made with an elevated serum TSH and depressed free T4. If you were to do imaging, a thyroid ultrasound or thyroid uptake scan with technetium-99m or iodine-123 could be done to look for hypoplastic or ectopic thyroid tissue. Editor's note: Stay tuned, as next week's theme is thyroid imaging!