Establishment of an animal model of dural venous sinus embolism*★

BACKGROUND： The pathological mechanism of secondary brain lesion following an embolism remains unclear. The establishment of an animal model that imitates the clinical pathophysiological processes is crucial to better study this disease during a certain time window. OBJECTIVE： To establish a new animal model of dural venous sinus embolism that is simple, has a high success rate, and emulates the pathophysiological course of clinical disease. DESIGN, TIME AND SETTING： A randomized block design trial was performed at the Department of Anatomy, Ningxia Medical College between March and December 2007. MATERIALS： Fifty-eight healthy, adult, Sprague Dawley rats were used in the present study. Plastic emboli, with a total length of 0.4 cm, were self-made. Each plastic embolus had a conical anterior segment; the largest diameter being 0.12 cm. The posterior segment became gradually thin and flat, with a width of 0.2 cm and length of 0.1 cm. METHODS： The fifty-eight rats were randomly divided into three groups： control （n = 6）, embolism （n = 26）, and sham-embolism （n = 26） groups. In the embolism group, a solid embolus was slowly inserted and fixed into the posterior part of the superior sagittal sinus against the flow of blood. The posterior segment was detained outside the superior sagittal sinus for fixing. In the sham-embolism group, rats were subjected only to sinus sagittalis superior exposure. In the control group, rats received no treatments. In both the embolism and the sham-embolism groups, the rat brains were resected at 6 hours, 1, 3, and 5 days post-surgery. MAIN OUTCOME MEASURES： （1） Brain surface appearance in the embolism and sham-embolism groups. （2） Thrombosis in the embolism group. （3） Cerebrospinal fluid content in the above-mentioned two groups. RESULTS： In the embolism group, the model success rate was 92% （24/26）. There was visible thrombosis in the superior sagittal sinus. Cerebral edema was noticeable under a microscope. These changes were visible at 6 h

Establishment of an animal model of dural venous sinus embolism

BACKGROUND: The pathological mechanism of secondary brain lesion following an embolism remains unclear. The establishment of an animal model that imitates the clinical pathophysiological processes is crucial to better study this disease during a certain time window.OBJECTIVE: To establish a new animal model of dural venous sinus embolism that is simple, has a high success rate, and emulates the pathophysiological course of clinical disease.DESIGN, TIME AND SETTING: A randomized block design trial was performed at the Department of Anatomy, Ningxia Medical College between March and December 2007.MATERIALS: Fifty-eight healthy, adult, Sprague Dawley rats were used in the present study. Plastic emboli, with a total length of 0.4cm, were self-made. Each plastic embolus had a conical anterior segment; the largest diameter being 0.12cm. The posterior segment became gradually thin and flat, with a width of 0.2cm and length of 0.1cm.METHODS: The fifty-eight rats were randomly divided into three groups: control (n=6), embolism (n=26), and sham-embolism (n=26) groups. In the embolism group, a solid embolus was slowly inserted and fixed into the posterior part of the superior sagittal sinus against the flow of blood. The posterior segment was detained outside the superior sagittal sinus for fixing. In the sham-embolism group, rats were subjected only to sinus sagittalis superior exposure. In the control group, rats received no treatments. In both the embolism and the sham-embolism groups, the rat brains were resected at 6 hours, 1,3, and 5 days post-surgery.MAIN OUTCOME MEASURES: (1) Brain surface appearance in the embolism and sham-embolism groups. (2) Thrombosis in the embolism group. (3) Cerebrospinal fluid content in the above-mentioned two groups.RESULTS: In the embolism group, the model success rate was 92%(24/26). There was visible thrombosis in the superior sagittal sinus. Cerebral edema was noticeable under a microscope. These changes were visible at 6 hours after embolism and were most obvious at 1 day after surgery. In the embolism group, cerebrospinal fluid content reached a peak level at 6 hours post-surgery and was significantly increased compared with the sham-embolism and the control groups (P<0.05). At 1 day post-surgery, the amount of cerebrospinal fluid was still greater in the embolism group compared to the control group (P<0.05)CONCLUSION: The method of inserting a solid embolus has many benefits, such as being able to directly observe, short cycle time, and minimal wound. The detained posterior segment prevents movement and perfusion of embolus, which results in a high success rate.