cortical ribbon sign
Early CT finding of acute stroke characterized by loss of gray-white matter differentiation in the cerebral cortex.
Full Definition
The cortical ribbon sign is an early and subtle CT finding in acute ischemic stroke that manifests as loss of the normal gray-white matter distinction along the cerebral cortex. This sign appears as hypodensity or obscuration of the cortical ribbon, typically within the first few hours of stroke onset. It represents early cytotoxic edema and is often more apparent than frank hypodensity in hyperacute stroke. Recognition of this sign is crucial for stroke diagnosis and treatment decisions, as it may be the only visible abnormality on non-contrast CT in the early stages of cerebral infarction.
Usage
Usage note: Often described as subtle; quantify extent when possible.
In Context
- "Subtle cortical ribbon sign was evident in the left MCA territory on the initial non-contrast CT." — Emergency radiology report
- "The absence of cortical ribbon sign within the therapeutic window supported the decision for thrombolysis." — Treatment planning