Phlebitis and thrombophlebitis of intracranial venous sinuses

This code represents inflammation of the intracranial venous sinuses, often accompanied by thrombus formation. This condition can affect various sinuses within the skull, such as the superior sagittal, transverse, or cavernous sinuses. It typically results from infection spreading from nearby structures or from systemic prothrombotic states.

Use this code when documentation clearly indicates a diagnosis of phlebitis or thrombophlebitis affecting any of the venous sinuses within the cranium. This includes cases where the specific sinus is identified (e.g., cavernous sinus thrombosis) or when a more general intracranial venous sinus involvement is stated. Supporting documentation would include imaging reports (MRI, CT venography) confirming the thrombus and/or inflammation, and physician notes detailing the clinical presentation and diagnosis.

• Specify the underlying cause or associated infection whenever possible by coding it first.
• Distinguish from cerebral venous thrombosis (CVT) that may involve cortical veins rather than primarily the major sinuses.
• Review documentation for laterality if specified, though this code does not differentiate.