Age Estimation of Ischemic Stroke by MRI Patterns
Selective neuronal necrosis on MRI is not a validated imaging marker for estimating the age of an ischemic cerebral infarction in clinical practice. MRI stroke dating is instead based on sequence-dependent evolution patterns on DWI/ADC and FLAIR and on unenhanced and contrast-enhanced T1- and T2-weighted sequences. [1]
Imaging Basis for Infarct Dating
Age estimation of ischemic infarction is performed using temporal changes in restricted diffusion on DWI/ADC, temporal changes on FLAIR, and subsequent signal evolution on T1- and T2-weighted sequences. [1]
Relation of “Selective Neuronal Necrosis” to MRI Timeline
“Selective neuronal necrosis” is primarily used as a neuropathologic or experimental concept describing tissue fate after ischemia rather than as a standardized, human-validated MRI feature for infarct age dating. [2]
Evidence Gap for Selective Neuronal Necrosis–Based Dating
Experimental work describes distinct temporal MR relaxation behavior in selective neuronal necrosis after transient focal ischemia in rats, but this does not constitute a clinically validated method to infer infarct onset time in humans. [3]
Clinical Implication for Use in Practice
When infarct age is required, sequence-specific MRI dating frameworks should be used instead of attempting to infer time from the presence of selective neuronal necrosis terminology alone. [1]
Most Reliable Alternatives
The most clinically used MRI approach for estimating whether an infarct is early versus later uses DWI restriction patterns in combination with FLAIR signal change and the degree of subsequent T1/T2 evolution. [1]