Ventriculoatrial shunting via the azygos vein.

The treatment of hydrocephalus has evolved through many stages but the "cure" is still elusive. It is not unusual for the neurosurgeon to find that the commonly used routes for catheter placement or sites for drainage of cerebrospinal fluid (CSF) cannot be employed. The azygos vein was used to gain access to the right atrium when the CSF could not be drained into the peritoneal cavity, nor could the neck veins be used to place the catheter into the right atrium. The azygos vein is a convenient and safe route to reach the right atrium in selected patients.