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Updated: Jul 2, 2026
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Analysis of Cerebral Vasospasm in a Murine Model of Subarachnoid Hemorrhage with High Frequency Transcranial Duplex Ultrasound
Published on: June 3, 2021
Diffusion-perfusion mismatch in symptomatic vasospasm after subarachnoid hemorrhage
Tatsuya Ohtonari1, Kenichi Kakinuma, Tomohiro Kito
1Department of Neurosurgery, Cerebrovascular Center, Niigata Rosai Hospital, Joetsu, Japan. otonari1@alpha.ocn.ne.jp
Neurologia Medico-Chirurgica
|August 23, 2008
Summary
Diffusion-perfusion mismatch detected by advanced MRI may help identify early vasospasm after subarachnoid hemorrhage. This imaging technique shows promise for timely diagnosis and treatment initiation.
Area of Science:
- Neurology
- Radiology
- Medical Imaging
Background:
- Subarachnoid hemorrhage (SAH) following aneurysm clipping can lead to vasospasm.
- Early detection of vasospasm is crucial for preventing ischemic complications.
- Current diagnostic methods for vasospasm may have limitations in early detection.
Purpose of the Study:
- To evaluate the utility of diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) in detecting early vasospasm.
- To assess the role of diffusion-perfusion mismatch in identifying ischemic changes.
- To compare the efficacy of MRI techniques with single photon emission computed tomography (SPECT).
Main Methods:
- Seventeen patients with acute SAH post-aneurysm clipping were studied.
- Diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) were performed.
- Single photon emission computed tomography (SPECT) using N-isopropyl-p-[(123)I]iodoamphetamine was also utilized.
Main Results:
- Diffusion-perfusion mismatch was clearly identified in patients with clinical deterioration.
- PWI revealed increased mean transit time, normal cerebral blood flow, and altered cerebral blood volume.
- SPECT did not show earlier signs of vasospasm compared to MRI.
Conclusions:
- Diffusion-perfusion mismatch demonstrated by DWI/PWI is a sensitive indicator of early vasospasm.
- This MRI-based approach may facilitate early identification of ischemia.
- Prompt diagnosis can lead to timely initiation of appropriate treatment for vasospasm.
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