Mismatch of delayed perfusion volume between TTP and Tmax map of perfusion MRI

Area of Science:

• Neurology
• Radiology
• Medical Imaging

Background:

• Acute stroke management requires accurate prediction of infarct progression.
• Perfusion-weighted imaging (PWI) and diffusion-weighted imaging (DWI) mismatches identify patients with potential for reperfusion.
• Predicting infarct evolution in mismatch patients with persistent vascular occlusion is clinically important.

Purpose of the Study:

• To identify novel imaging parameters that predict infarct volume change in acute stroke patients with a PWI-DWI mismatch.
• To evaluate the utility of time-to-peak and time-to-max (TTP-Tmax) perfusion delay mismatch volume as a predictive parameter.

Main Methods:

• Retrospective review of 54 acute stroke patients with PWI-DWI mismatch and vascular occlusion on initial MRI.
• Analysis of patients with no recanalization of the occluded vessel.
• Statistical analysis to determine correlates of infarct volume change.

Main Results:

• Time-to-peak and time-to-max (TTP-Tmax) perfusion mismatch volume was a significant independent correlate of infarct volume change (P=.004).
• A larger TTP-Tmax perfusion delay mismatch volume was associated with less infarct expansion.

Conclusions:

• A large TTP-Tmax perfusion delay mismatch volume in acute stroke patients with PWI-DWI mismatch may indicate a stable infarct size.
• This finding suggests that infarct volume may not increase despite persistent vascular occlusion in selected patients.
• TTP-Tmax perfusion delay mismatch volume could be a valuable parameter for predicting infarct evolution in acute stroke.