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Brain Infarct Segmentation and Registration on MRI or CT for Lesion-symptom Mapping
Published on: September 25, 2019
Initial brain lesion size affects the extent of subsequent pathophysiological responses
Nobuo Nagai1, Naoyuki Kawao, Kiyotaka Okada
1Department of Physiology, Kinki University School of Medicine, Japan. nagainnn@med.kindai.ac.jp
Brain Research
|February 9, 2010
Summary
Stroke severity varies, but initial brain lesion size impacts recovery. Larger lesions trigger stronger inflammatory responses, including microglia and astrocyte activation, suggesting damage extent dictates healing. Understanding this relationship aids stroke treatment strategies.
Area of Science:
- Neuroscience
- Pathophysiology
- Stroke Research
Background:
- Ischemic stroke severity varies due to individual artery occlusion and distal vessel territories.
- The link between initial brain lesion extent and subsequent pathophysiological responses remains unclear.
Purpose of the Study:
- To investigate how initial brain lesion size influences subsequent pathophysiological responses in ischemic stroke.
- To compare lesion size control between photochemically induced thrombotic brain damage (PIT-BD) and middle cerebral artery occlusion (MCA-O) models.
Main Methods:
- Utilized a photochemically induced thrombotic brain damage (PIT-BD) model for reproducible lesion size control.
- Compared lesion size reduction and glial cell activation (microglia, astrocytes) in mice with large versus small lesions.
- Investigated the role of urokinase-receptor (uPAR) deficiency in lesion resolution using both MCA-O and PIT-BD models.
Main Results:
- In the PIT-BD model, larger lesions (4.9% brain) showed greater reduction (56%) by day 7 than smaller lesions (1.3% brain, 30% reduction).
- Microglia and astrocyte activation was significantly lower in mice with smaller lesions compared to those with larger lesions on day 5.
- In the MCA-O model, uPAR(-/-) mice with smaller initial lesions showed less reduction, but comparable reduction was observed in uPAR(-/-) and wild-type mice with similar lesion sizes in the PIT-BD model.
Conclusions:
- Initial brain lesion size is a critical determinant of subsequent pathophysiological responses in ischemic stroke.
- Greater initial brain damage elicits a stronger inflammatory and cellular response, influencing lesion resolution.
- Findings suggest that the observed differences in lesion resolution in uPAR(-/-) mice were due to initial lesion size, not solely gene deficiency.
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