A 4-year-old boy is brought to the physician because of a progressive headache and neck pain for 2 weeks. During this period, he has had multiple episodes of dizziness and tingling sensations in his arms and hands. His neck is supple. Neurological examination shows gait ataxia. Brain imaging shows caudal displacement of cerebellar tonsils. Which of the following is the most likely cause of this patient's condition?

Question

Quizplus · Accepted Answer

Eductional Objective: Chiari malformations are congenital disorders that result from underdevelopment of the posterior fossa, causing parts of the cerebellum and medulla to herniate through the foramen magnum.  Chiari type I is relatively benign and presents during adulthood with occipital headache and cerebellar dysfunction.  Chiari type II is a more severe form that affects neonates and is often associated with lumbar myelomeningocele and hydrocephalus.

A 4-Year-Old Boy Is Brought to the Physician Because of a Progressive