Acquired Chiari Malformation: Safety of Neuraxial Anesthesia?

Chiari malformation is a congenital anomaly that primarily involves the downward displacement of the cerebellar tonsils through the foramen magnum and elongation of forth ventricle and lower brainstem. Patients with Chiari I (congenital or acquired) malformation are asymptomatic or may present with neurologic signs and symptoms. It is always a question of safety of neuraxial anesthesia in these patients. There is potential risk of dural puncture that can initiate the neurologic symptoms or worsen the existing symptoms due to CSF leakage or tonsillar herniation. Other side, performance of neuraxial anesthesia can cause acquired Chiari I type malformation due to CSF leak and intracranial hypotension. We reviewed the case reports and articles regarding safety of neuraxial anesthesia in the setting of Congenital or Acquired Chiari malformation.