Clinical Presentation of Adult Chiari I

Adult patients with Chiari malformation, sometimes referred to as hindbrain descent, most frequently present with symptoms in their 20s and 30s. Symptoms include those that can be attributed to interference with normal cerebrospinal fluid (CSF) flow equalization. Exertionally related headaches, characteristic for Chiari malformation, are due to this mechanism and are also the most common of all Chiari-related symptoms. Symptoms may also be related to brainstem compression and compression of cerebellar connections, reflected in balance problems, visual problems, and autonomic symptoms. Symptoms related to traction on lower cranial nerves may include swallowing and voice problems and may contribute to sleep apnea. Chiari malformation and related symptoms may present as a manifestation of other diseases, including hypophosphatemic rickets, Paget’s disease, Crouzon’s disease, and achondroplasia. Secondary Chiari malformation may be seen with pseudotumor cerebri (idiopathic intracranial hypertension) and occult cerebrospinal fluid leaks.