Greene classification

The CT grading scale proposed by Greene and colleagues stratifies tSAH based on the extent and distribution of hemorrhage observed on head CT scans. The scale includes the following categories:

Grade 0:

No evidence of subarachnoid hemorrhage on the CT scan. Grade 1:

Localized subarachnoid hemorrhage confined to one cistern or fissure. Grade 2:

Subarachnoid hemorrhage involving more than one cistern or fissure but not diffuse. Grade 3:

Diffuse subarachnoid hemorrhage across multiple cisterns or fissures. Grade 4:

Diffuse subarachnoid hemorrhage accompanied by intraventricular hemorrhage or intracerebral hematoma. Clinical Implications of the Greene Classification Correlation with Outcomes:

Higher grades (3 and 4) are associated with worse clinical outcomes, including higher mortality and lower functional recovery rates. Lower grades (0 and 1) tend to have better prognoses. Prognostic Value:

The extent and distribution of hemorrhage reflect the severity of the initial traumatic event and are predictors of intracranial pressure (ICP) dynamics, secondary brain injury, and overall outcomes. Management Implications:

Higher-grade tSAH often requires more aggressive management, including ICP monitoring, sedation, and surgical interventions if needed. Lower-grade tSAH may be managed conservatively with close monitoring and supportive care. Significance of the Study The Greene classification provides a systematic and standardized approach to grading tSAH severity on CT imaging. It helps clinicians:

Stratify patients for treatment decisions. Predict outcomes more accurately. Compare results across clinical studies.

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