Nonpyogenic thrombosis of intracranial venous sinus

This code signifies the presence of a blood clot within one of the venous sinuses of the brain, not caused by an infection. This condition, also known as cerebral venous sinus thrombosis (CVST), can impede blood drainage from the brain, potentially leading to increased intracranial pressure, stroke, or hemorrhage.

Use this code for diagnoses of cerebral venous sinus thrombosis where infectious etiologies have been ruled out. Documentation should clearly state the presence of a thrombus in an intracranial venous sinus, often identified through imaging studies like MRI or CT venography, and specify its nonpyogenic nature.

• Differentiate from septic intracranial thrombophlebitis (e.g., 325), which involves an infectious origin.
• Code any associated neurological deficits or complications, such as cerebral infarction, separately.
• Ensure documentation specifies the affected sinus(es) if known, although this code is general for any nonpyogenic intracranial venous sinus thrombosis.