Related Experiment Video
Updated: Sep 4, 2025
Brain Infarct Segmentation and Registration on MRI or CT for Lesion-symptom Mapping
Published on: September 25, 2019
Susceptibility-Weighted MRI as an Imaging Marker for Reperfusion Injury in Acute Ischemic Stroke Following Mechanical
Jenny M Gandhi1, P Mathew Cherian1, Pankaj Mehta1
1Department of Neuro and Intervention Radiology, Kovai Medical Centre and Hospital, Avinashi Road, Coimbatore, Tamil Nadu, India.
Background/Purpose:
Following endovascular intervention for stroke, hyperattenuated areas are common in brain parenchyma and it is difficult to differentiate on non-contrast CT whether it is contrast staining or reperfusion hemorrhage. Differentiation between contrast staining from reperfusion hemorrhage is of paramount importance for early initiation of antiplatelets and/or anticoagulants to prevent reocclusion of vessel. This study demonstrates signal characteristics of contrast-staining and reperfusion hemorrhage on susceptibility weighted MRI and its role to differentiate between two.
Materials/Methods:
Between July 2017 to March 2019, 36 patients who presented with acute ischemic stroke due to large vessel occlusion underwent mechanical thrombectomy. Low-osmolar non-ionic (Iopromide 300 mg/L) iodinated contrast was used in all patients who underwent endovascular intervention. All patients underwent noncontrast CT brain and SWI on 3T MRI within 30 minutes of endovascular intervention. MRI was evaluated by two neuroradiologists. Reperfusion hemorrhage was defined as ECASS criteria II. Symptomatic ICH was defined as hemorrhagic transformation temporally related to a negative shift in NIHSS score >/=4.
Results:
Out of 36 patients, 15 had hyperattenuated areas in brain on NCCT. Out of 15, 13 patients had blooming on SWI, suggestive of bleed. Two patients had no blooming on SWI, suggestive of contrast staining. Two patients didnot show any hyperdensity on NCCT but blooming on SWI, suggestive of bleed.
Conclusion:
All patients with hyperdensity on NCCT secondary to bleed showed blooming on SWI whereas those with contrast staining didnot show any signal changes on SWI. Thus, it is possible to differentiate reperfusion hemorrhage from contrast staining using SWI MRI. The significance of SWI in normal CT may be low where a small bleed maynot have any clinical significance.
Insights
Susceptibility weighted MRI (SWI) can differentiate reperfusion hemorrhage from contrast staining after stroke intervention. SWI blooming indicates hemorrhage, while its absence suggests contrast staining, aiding treatment decisions.
Area of Science:
- Neuroradiology
- Neuroimaging
- Stroke Management
Background:
- Distinguishing post-stroke endovascular intervention contrast staining from reperfusion hemorrhage on non-contrast CT is challenging.
- Accurate differentiation is crucial for timely initiation of antiplatelet/anticoagulant therapy to prevent reocclusion.
- Susceptibility weighted MRI (SWI) may offer a solution for differentiating these findings.
Purpose of the Study:
- To evaluate the signal characteristics of contrast staining and reperfusion hemorrhage on SWI.
- To assess the role of SWI in differentiating between contrast staining and reperfusion hemorrhage after endovascular stroke intervention.
Main Methods:
- 36 patients with acute ischemic stroke undergoing mechanical thrombectomy were included.
- Noncontrast CT and 3T SWI MRI were performed within 30 minutes of intervention.
- Two neuroradiologists evaluated MRI for blooming, indicative of hemorrhage.
Main Results:
- 15 patients had hyperattenuated areas on NCCT; 13 showed SWI blooming (hemorrhage), 2 did not (contrast staining).
- Two patients without NCCT hyperdensity showed SWI blooming, indicating hemorrhage.
- All NCCT-identified bleeds demonstrated SWI blooming; contrast staining showed no signal changes on SWI.
Conclusions:
- SWI MRI effectively differentiates reperfusion hemorrhage from contrast staining after endovascular stroke intervention.
- SWI is valuable for identifying hemorrhage, even when subtle or absent on noncontrast CT.
- SWI can guide treatment decisions, potentially improving outcomes in stroke patients.
