Evaluation of ischemic penumbra in wake-up stroke patients based on mismatch of amide-proton transfer weighted imaging with DWI: a feasibility study / 中华神经医学杂志

ABSTRACT

Objective:To explore the feasibility of mismatch of amide proton transfer weighted (APTw) imaging with diffusion weighted imaging (DWI) in evaluating ischemic penumbra (IP) in patients with wake-up stroke.Methods:A prospective study was performed; 96 patients with wake-up stroke and unilateral middle cerebral artery territory infarction admitted to Emergency Stroke Department, Affiliated Hospital of Jining Medical University from September 2020 to January 2023 were chosen. All patients underwent routine MRI, DWI, APTw imaging and 3D arterial spin labeling (3D-ASL) before treatment and 90 d after treatment. IP presence was defined as changes of abnormal signal on T2-fluid-attenuated inversion recovery (FLAIR) 90 d after treatment greater than 20% of high signal range on DWI before treatment, and it was used as the gold standard to compare the efficacy in evaluating whether the patients had IP based on mismatch of 3D-ASLwith DWI and mismatch of APTw imaging with DWI before treatment. The infarct core (IC) region, mismatch region of APTw imaging with DWI, mismatch region of 3D-ASL with APTw imaging were delineated on the fusion images in patients with IP based on mismatch of 3D-ASLwith DWI and mismatch of APTw with DWI, and the differences of APTw values in different regions were compared.Results:According to the 90-d follow-up results, 50 patients had IP and 46 patients did not have IP. Specificity, accuracy and sensitivity evaluating whether the patients had IP based on mismatch of 3D-ASL with DWI were 86.9%, 93.7% and 100.0%, respectively; specificity, accuracy and sensitivity evaluating whether the patients had IP based on mismatch of APTw imaging with DWI were 100.0%, 95.8% and 92.0%, respectively. The APTw max, APTw min and APTw ave values of the IC region were significantly lower than those of mismatch region of APTw with DWI, and the APTw max-min values of mismatch region of APTw imaging with DWI were significantly higher than those of mismatch region of 3D-ASL with APTw imaging ( P<0.05). Conclusion:APTw imaging can reflect the acidosis status of different brain regions in patients with wake-up stroke; specificity and accuracy evaluating whether the patients have IP based on mismatch of APTw imaging with DWI are higher than those based on mismatch of 3D-ASL with DWI.