Nontraumatic chronic subdural hemorrhage

This code signifies a slow, ongoing accumulation of blood between the dura mater and the arachnoid mater, occurring without a recent traumatic event. This type of hemorrhage typically develops over days or weeks, often due to the tearing of bridging veins as the brain atrophies, common in elderly patients.

Apply this code when documentation clearly indicates a subdural hemorrhage that is chronic and not attributed to acute trauma. This is frequently seen in patients presenting with insidious neurological symptoms such as headache, confusion, or weakness, where imaging (CT or MRI) confirms the presence of a chronic subdural collection.

• Differentiate carefully between acute, subacute, and chronic subdural hemorrhages based on imaging and clinical presentation.
• Ensure documentation specifies "nontraumatic" or provides no evidence of a recent traumatic cause.
• Consider sequencing this code as a principal diagnosis if it is the primary reason for the encounter, or as a secondary diagnosis if it complicates another condition.