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Updated: Jul 5, 2026
Advanced Diffusion Imaging in The Hippocampus of Rats with Mild Traumatic Brain Injury
Published on: August 14, 2019
Serial diffusion and perfusion MRI analysis of the perihemorrhagic zone in a rat ICH model
B Orakcioglu1, K Becker, O W Sakowitz
1Department of Neurosurgery, University Hospital Heidelberg, Heidelberg, Germany. berk.orakcioglu@med.uni-heidelberg.de
Objectives:
Cerebral ischemia has been proposed as a contributing mechanism to secondary neuronal injury after intracranial hemorrhage (ICH). We aimed to examine perihemorrhagic changes with an animal experimental MRI study using a stroke-MRI protocol. In a subset of animals the feasibility and effects of stereotactic hematoma evacuation was investigated.
Methods:
An MRI compatible setup for rats was established using a double injection model. ICH was stereotactically placed into the right basal ganglia of 49 Wistar rats. Coronal T2-WI, T2*-WI, DWI and PWI were generated with a 2.35T animal MRI scanner at 3 time points. Clot volumes, normalized ADC and relative MTT values were analysed in 3 hematoma regions (periphery, outer rim, healthy ipsilateral tissue) in all sequences.
Results:
There were no perihemorrhagic ADC decreases consistent with ischemic cytotoxic edema but a mild vasogenic edema surrounding the ICH could be observed. This improved partially with evacuation. Reduced perfusion was seen in the periphery and outer rim. This disappeared with lysis and evacuation of the clot.
Conclusion:
No evidence for the existence of a perihemorrhagic ischemic area was found. But, reversible perfusion reduction in this model indicates that early evacuation may help reducing secondary neuronal changes.
Insights
This study found no evidence of perihemorrhagic ischemia after intracranial hemorrhage (ICH) in rats. However, reduced blood flow around the clot was reversible, suggesting early hematoma evacuation may limit secondary brain injury.
Area of Science:
- Neuroscience
- Radiology
- Neurosurgery
Background:
- Intracranial hemorrhage (ICH) can cause secondary neuronal injury.
- Cerebral ischemia is a proposed mechanism contributing to this injury.
- Understanding perihemorrhagic changes is crucial for developing effective treatments.
Purpose of the Study:
- To investigate perihemorrhagic changes using advanced MRI techniques in a rat model of ICH.
- To assess the feasibility and effects of stereotactic hematoma evacuation.
Main Methods:
- Stereotactic ICH induction in 49 Wistar rats.
- High-resolution MRI (T2-WI, T2*-WI, DWI, PWI) at 3 time points.
- Analysis of clot volume, apparent diffusion coefficient (ADC), and mean transit time (MTT) in perihematomal regions.
Main Results:
- No evidence of cytotoxic edema (ischemic changes) surrounding the hematoma.
- Mild vasogenic edema observed, which partially improved after evacuation.
- Reduced cerebral blood flow (perfusion) in the periphery and outer rim of the hematoma, resolving with clot lysis and evacuation.
Conclusions:
- The study found no evidence of a perihemorrhagic ischemic area in this ICH model.
- Reversible perfusion reduction suggests that early surgical evacuation of the hematoma may mitigate secondary neuronal damage.
