Obstructive hydrocephalus

This code represents a condition where there is an abnormal accumulation of cerebrospinal fluid (CSF) within the brain's ventricles due to a blockage in its normal flow pathways. This obstruction leads to increased intracranial pressure and ventricular enlargement.

Use this code when documentation clearly indicates hydrocephalus caused by a structural impediment to CSF circulation, such as aqueductal stenosis, tumor compression, or congenital malformations. This applies to both communicating and non-communicating types where an obstruction is the underlying cause.

• Differentiate from communicating hydrocephalus without obstruction (e.g., impaired absorption), which would be coded differently.
• Always code the underlying cause of the obstruction if known and documented (e.g., brain tumor, congenital anomaly).
• Review imaging reports (CT, MRI) and physician notes for specific anatomical locations of the obstruction.