Establishment Of Animal Intracerebral Hemorrhage Model And Experimental Research Of Interventional Ultrasound

Objective:1. To explore a method of establishing a canine model ofintracerebral hemorrhage (ICH) by puncturing the main branch of middle cerebralartery (MCA) under ultrasonic guidance.2. To explore the ICH characteristics ofcontrast-enhanced ultrasound (CEUS) in experimental dogs.3. To preliminarilyexplore the feasibility of hemostatic therapy for ICH by interventional ultrasound.Methods:1.Twelve healthy mongrel dogs were enrolled in the experiment.In the condition of bone window, the main branch of MCA was punctured to bleedunder the ultrasonic guidance. Two-dimensional ultrasound and CEUS of brainwere conducted immediately,30min and1h after modeling, respectively, toobserve the lesion echo and bleeding area. CT scans were also conducted at1hourafter modeling, and another CEUS was performed at24h. Then brains werecollected for pathologic examination after dogs were euthanized.2. Another3dogs were made ICH models. Hemostatics, including thrombin，rFⅦa, and saline,were injected locally to the active bleeding areas under the guidance of CEUSrespectively, and then to observe the changes of bleeding areas after10min.Results:1. Eleven of twelve dogs developed ICH successfully that located inthe out edge of basal ganglia, which was confirmed by CT, CEUS andpathological examination. One dog died within6hours due to intraventricularhemorrhage which was confirmed by autopsy.2. The hematoma diameters were measured on brain specimens and byCEUS before euthanasia. There was no statistical difference between the twomethods on the measurements（P>0.05）.3. Two-dimensional ultrasound of ICH showed irregular agglomeratehigh-echo, unclear boundary, but it didn t show active bleeding. CEUS of activebleeding showed that contrast agent overflowed extravascularly and pooled, enhanced obviously. CEUS of hematoma showed lack of perfusion with low andno enhancement, clear boundary, while the normal cerebral tissue was enhanced.There was no statistical difference between CEUS (1h) and CT on themeasurements (P>0.05). The lesion sizes of30min and1h continued to increaseafter modeling, and there were both significant statistical differences comparingwith the immediate ones(P<0.01)，while there was no statistical differencebetween the measurements of30min and1h(P>0.05).4. The images showed that the active bleeding stopped after the hemostaticsinjected under the guidance of CEUS.Conclusion:1.A model of canine ICH by puncturing the main branch ofMCA under the guidance of ultrasound was established successfully, and it provedto be simple, effective and repeatable.2. CEUS can help show the extent and scope of ICH, and dynamically showthe process of it.3. The therapy for ICH active bleeding with local injection hemostaticsunder the guidance of CEUS is feasible.