Early diffusion-weighted imaging reversal after endovascular reperfusion is typically transient in patients imaged 3 to 6 hours after onset.

Background And Purpose: The aim of this study was to assess the frequency and extent of early diffusion-weighted imaging (DWI) lesion reversal after endovascular therapy and to determine whether early reversal is sustained or transient.

Methods: MRI with DWI perfusion imaging was performed before (DWI 1) and within 12 hours after (DWI 2) endovascular treatment; follow-up MRI was obtained on day 5. Both DWIs were coregistered to follow-up MRI.

Clinical outcomes strongly associated with the degree of reperfusion achieved in target mismatch patients: pooled data from the Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution studies.

Background And Purpose: To investigate relationships between the degree of early reperfusion achieved on perfusion-weighted imaging and clinical outcomes in the Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution studies. We hypothesized that there would be a strong correlation between the degree of reperfusion achieved and clinical outcomes in target mismatch (TMM) patients.

Methods: The degree of reperfusion was calculated on the basis of the difference in perfusion-weighted imaging volumes (time to maximum of tissue residue function [Tmax]>6 s) between the baseline MRI and the early post-treatment follow-up scan.

Early diffusion-weighted imaging and perfusion-weighted imaging lesion volumes forecast final infarct size in DEFUSE 2.

Background And Purpose: It is hypothesized that early diffusion-weighted imaging (DWI) lesions accurately estimate the size of the irreversibly injured core and thresholded perfusion-weighted imaging (PWI) lesions (time to maximum of tissue residue function [Tmax] >6 seconds) approximate the volume of critically hypoperfused tissue. With incomplete reperfusion, the union of baseline DWI and posttreatment PWI is hypothesized to predict infarct volume.

Methods: This is a substudy of Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution Study 2 (DEFUSE 2); all patients with technically adequate MRI scans at 3 time points were included.

MRI profile and response to endovascular reperfusion after stroke (DEFUSE 2): a prospective cohort study.

Background: Whether endovascular stroke treatment improves clinical outcomes is unclear because of the paucity of data from randomised placebo-controlled trials. We aimed to establish whether MRI can be used to identify patients who are most likely to benefit from endovascular reperfusion.

Methods: In this prospective cohort study we consecutively enrolled patients scheduled to have endovascular treatment within 12 h of onset of stroke at eight centres in the USA and one in Austria.

Evaluation of respiratory liver and kidney movements for MRI navigator gating.

Purpose: To determine the tracking factor by studying the relationship between kidney and diaphragm motions and to compare the efficiency of the gating-and-following and gating-only algorithms in reducing motion artifacts in navigator-gated scans.

Materials And Methods: Diaphragm and kidney motions were measured by using real-time TrueFISP sequences from 10 healthy human volunteers to determine tracking factors at different acceptance windows. Mean tracking factors were used to calculate mean residual errors and improvement factors for the gating-and-following and gating-only algorithms.