Ntrm subarach hemorrhage from left carotid siphon and bifurc

This code signifies bleeding into the subarachnoid space, specifically originating from a non-traumatic rupture of an aneurysm or other vascular malformation located at the carotid siphon or bifurcation on the left side of the brain. This type of hemorrhage is a serious medical emergency often presenting with a sudden, severe headache.

Use this code when documentation clearly indicates a spontaneous (nontraumatic) subarachnoid hemorrhage. The physician's notes must specify the origin as the left carotid siphon or bifurcation, typically confirmed by imaging studies such as CT angiography or cerebral angiography.

• Differentiate from traumatic subarachnoid hemorrhage, which has distinct coding.
• Ensure the laterality (left) and specific anatomical site (carotid siphon and bifurcation) are explicitly documented.
• If the hemorrhage is from an unspecified carotid artery or an unspecified site, a different code would be appropriate.