J Korean Radiol Soc.  2005 Oct;53(4):253-262. 10.3348/jkrs.2005.53.4.253.

A Middle Cerebral Artery Occlusion Model in Rabbits: Development with Endovascular Interventional Techniques and Evaluation by Magnetic Resonance Imaging

• Lee DH
• Choi CG
• Kim SJ
• Cha SH
• Park KS

• KMID: 2103784
• DOI: http://doi.org/10.3348/jkrs.2005.53.4.253

Abstract

PURPOSE: The aim of this study was to develop a new middle cerebral artery occlusion (MCAO) model in rabbits using a less invasive, endovascular interventional technique. The new animal model's technical feasibility and its success in producing lesions was evaluated using magnetic resonance imaging (MRI).
MATERIALS AND METHODS
Ten rabbits were used to develop the MCAO models using a transfemoral catheter-based technique. After catheterization of the common carotid artery, a microcatheter was introduced coaxially through the catheter to cannulate the internal carotid artery and to embolize the MCA with polyvinyl alcohol particles. We evaluated how successful we were in selecting the vessels, catheterization, embolization, and also evaluated how many of the animals survived until the end of experiment. Diffusion-weighted imaging (DWI) and T2-weighted imaging (T2WI) were performed in one-hour intervals to monitor the ischemic lesion for a total of six hours following successful occlusion of the target artery. The relative volume of the lesion was calculated as a hemispheric lesion volume (HLV, %). The signals of the lesion and contralateral normal brain (control) were measured in each image at every time point. Lesion-to-control signal-intensity ratio (SIR) of DWI, and T2WI were obtained together with relative apparent diffusion coefficient (rADC).
RESULTS
Catheterization and embolization of the internal carotid artery were successful in all 10 rabbits, which showed relevant lesions on MRI. All rabbits survived until the end of the experiment. The HLV (mean+/-standard deviation) was 35.7+/-14.6%. The relative ADC was 0.80+/-0.13. The lesion signals on DWI and T2WI showed a gradual increase as time passed, while the ADC value of the lesion gradually decreased (p<0.0001).
CONCLUSION
The rabbit MCAO model using an endovascular interventional technique is technically feasible, and provides a reproducible lesion in the target arterial territory. MRI successfully revealed a typical finding of acute cerebral infarction. This model is also believed to be suitable for the MRI investigation of acute cerebral ischemia.

Keyword

Brain ischemia; Brain infarction; Animal model; Ischemia model; Endovascular technique; Magnetic resonance imaging; Diffusion-weighted image

MeSH Terms

Animals
Arteries
Brain
Brain Infarction
Brain Ischemia
Carotid Artery, Common
Carotid Artery, Internal
Catheterization
Catheters
Cerebral Infarction
Diffusion
Endovascular Procedures
Infarction, Middle Cerebral Artery*
Magnetic Resonance Imaging*
Middle Cerebral Artery*
Models, Animal
Polyvinyl Alcohol
Rabbits*
Polyvinyl Alcohol