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Updated: Aug 23, 2026
Integrated Photoacoustic, Ultrasound, and Angiographic Tomography (PAUSAT) for NonInvasive Whole-Brain Imaging of Ischemic Stroke
Published on: June 2, 2023
Contribution of susceptibility-weighted imaging to acute stroke assessment
Marc Hermier1, Norbert Nighoghossian
1Department of Neuroradiology and MRI, and the Cerebrovascular Disease Center, CREATIS, CNRS UMR 5515, INSERM U630 Hôpital Neurologique P. Wertheimer, Claude-Bernard Lyon-I University, Lyon, France.
Background:
Susceptibility-weighted (SW) MRI provides insight into the pathophysiology of acute stroke. We report on the use of SW imaging (SWI) sequences in clinical practice and highlight the future applications.
Summary Of Review:
SWI exploits the magnetic susceptibility effects generated by local inhomogeneities of the magnetic field. The paramagnetic properties of deoxyhemoglobin support signal changes related to acute hemorrhage and the intravascular spontaneous blood oxygen level dependent (BOLD) effect. SWI allows the early detection of acute hemorrhage within 6 hours after symptom onset. SWI may also identify previous microbleeds in acute ischemia; however, the impact of these findings on thrombolytic therapy safety has not been definitely established. The diagnosis of arterial occlusion is usually performed by magnetic resonance angiography. SWI allows intravascular clot detection at the acute stage.Substantial experimental data suggest that spontaneous BOLD contrast may improve tissue viability assessment. The ratio of oxyhemoglobin to deoxyhemoglobin, measured by MRI in the capillary and venous compartments, reflects the oxygen extraction fraction (OEF) and the cerebral metabolic rate of oxygen. The combination of magnetic resonance (MR)-measured OEF and cerebral blood flow, via perfusion studies, may provide information about tissue viability.
Conclusions:
SWI offers a spectrum of current clinical applications and may improve our knowledge of the pathophysiology of acute stroke.
Insights
Susceptibility-weighted imaging (SWI) using MRI offers early detection of acute stroke complications like hemorrhage and arterial occlusion. This advanced technique provides valuable insights into stroke pathophysiology and potential future clinical applications.
Area of Science:
- Neuroimaging
- Medical Physics
Background:
- Susceptibility-weighted (SW) MRI is crucial for understanding acute stroke pathophysiology.
- This review focuses on the clinical use and future potential of SW imaging (SWI) sequences.
Purpose of the Study:
- To review current clinical applications of SWI in acute stroke.
- To highlight emerging and future applications of SWI in stroke management.
Main Methods:
- SWI leverages magnetic susceptibility effects from local magnetic field inhomogeneities.
- It detects signal changes related to deoxyhemoglobin, acute hemorrhage, and the blood oxygen level dependent (BOLD) effect.
Main Results:
- SWI enables early detection of acute hemorrhage within 6 hours of symptom onset.
- It can identify microbleeds in acute ischemia and detect intravascular clots.
- SWI may aid in assessing tissue viability by measuring oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen.
Conclusions:
- SWI presents a range of current clinical applications in acute stroke.
- Further research utilizing SWI can enhance our understanding of stroke pathophysiology.