MRI of ischemic stroke in canines: applications for monitoring intraarterial thrombolysis.
OBJECTIVE
To describe a canine embolic stroke model that is appropriate for endovascular procedure evaluations and develop local cerebral blood flow (CBF) maps to monitor the progression of stroke and thrombolysis. In the future, MR may displace X-ray imaging in some endovascular procedures, such as intraarterial (IA) thrombolysis for stroke therapy, due to increased monitoring capabilities. For MR to attain its full potential in endovascular therapy, the development of appropriate disease models and monitoring techniques is essential.


METHODS
The canine stroke model uses an injection of autologous clot to produce ischemic and infarcted tissue and produces a range of stroke severities within the anterior cerebral circulation. Local CBF maps were formed by using the catheter that would be in place to deliver the thrombolytic agent for treatment to deliver the gadolinium-based contrast agent for perfusion imaging.


RESULTS
After the injection of clot, changes on imaging were consistent with the progression of ischemic stroke. Local CBF maps showed perfusion changes with stroke progression and treatment.


CONCLUSIONS
We successfully demonstrate the progression of ischemic stroke in the canine to mimic the progression of human stroke. CBF maps to show local perfusion characteristics show great potential in the evaluation of stroke therapy.
Harris
Ashley D
AD
Seaman Family MR Research Centre, Foothills Medical Centre, Calgary Health Region, Calgary, Alberta, Canada.
Kosior
Jayme C
JC
Ryder
Ronda C
RC
Andersen
Linda B
LB
Hu
William Y
WY
Hudon
Mark
M
Morrish
William H
WH
Sevick
Robert J
RJ
Wong
John
J
Frayne
Richard
R
D000818:Animals; D002545:Brain Ischemia / Q000188:drug therapy* / Q000503:physiopathology*; D002560:Cerebrovascular Circulation; D003287:Contrast Media / Q000008:administration & dosage; D004195:Disease Models, Animal; D018450:Disease Progression; D004285:Dogs; D019786:Gadolinium DTPA / Q000008:administration & dosage; D007269:Injections, Intra-Arterial; D008279:Magnetic Resonance Imaging / Q000379:methods*; D020521:Stroke / Q000188:drug therapy* / Q000503:physiopathology*; D015912:Thrombolytic Therapy
D003287:Contrast Media; D019786:Gadolinium DTPA