This study was supported by grant Scientific Research Foundation for the High-level Talents, Fujian University of Traditional Chinese Medicine (X2019002-talents).

Procedures involving animal subjects have been approved by the Medical Norms and Ethics Committee of Wenzhou Medical University and are in accordance with the China legislation on the use and care of laboratory animals.
1. Preparation of the thread plug, SD rats, and experimental equipment
<ol>
	<li>Use a nylon thread with a diameter of 0.28 mm as the main body of the thread plug. 
	NOTE: The softness and hardness of the nylon thread should be moderate.</li>
	<li>Cover one end of the ny...

<ol>
	<li>Bousser, M. G., Ferro, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cerebral+venous+thrombosis:+an+update.">Cerebral venous thrombosis: an update.</a> Lancet Neurology. 6 (2), 162-170 (2007).</li><li>Guenther, G., Arauz, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cerebral+venous+thrombosis:+A+diagnostic+and+treatment+update.">Cerebral venous thrombosis: A diagnostic and treatment update.</a> Neurologia. 26 (8), 488-498 (2011).</li><li>Stam, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thrombosis+of+the+cerebral+veins+and+sinuses.">Thrombosis of the cerebral veins and sinuses.</a> New England Journal of Medicine. 352 (17), 1791-1798 (2005).</li><li>Einh&#228;upl, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=EFNS+guideline+on+the+treatment+of+cerebral+venous+and+sinus+thrombosis+in+adult+patients.">EFNS guideline on the treatment of cerebral venous and sinus thrombosis in adult patients.</a> European Journal of Neurology. 17 (10), 1229-1235 (2010).</li><li>Coutinho, J. 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O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cerebral+Blood+Flow+Alterations+in+a+Rat+Model+of+Cerebral+Sinus+Thrombosis.">Cerebral Blood Flow Alterations in a Rat Model of Cerebral Sinus Thrombosis.</a> Stroke. 24 (4), (1993).</li><li>R&#246;ttger, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+model+of+reversible+sinus+sagittalis+superior+thrombosis+in+the+rat:+magnetic+resonance+imaging+changes.">A new model of reversible sinus sagittalis superior thrombosis in the rat: magnetic resonance imaging changes.</a> Neurosurgery. 57 (3), 573-580 (2005).</li><li>Chen, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Photothrombosis+combined+with+thrombin+injection+establishes+a+rat+model+of+cerebral+venous+sinus+thrombosis.">Photothrombosis combined with thrombin injection establishes a rat model of cerebral venous sinus thrombosis.</a> Neuroscience. 306, 39-49 (2015).</li><li>Yang, H., Meng, Z., Zhang, C., Zhang, P., Wang, Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Establishing+a+new+rat+model+of+central+venous+sinus+thrombosis+and+analyzing+its+pathophysiological+and+apoptotic+changes.">Establishing a new rat model of central venous sinus thrombosis and analyzing its pathophysiological and apoptotic changes.</a> Journal of Neuroscience Methods. 203 (1), 130-135 (2012).</li><li>Longa, E. Z., Weinstein, P. R., Carlson, S., Cummins, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reversible+middle+cerebral+artery+occlusion+without+craniectomy+in+rats.">Reversible middle cerebral artery occlusion without craniectomy in rats.</a> Stroke. 20 (1), 84-91 (1989).</li><li>Fluri, F., Schuhmann, M. 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In this study, a new type of CVST model was successfully established by inserting a self-made thread plug into the SSS of SD rats. Additionally, laser-speckle blood-flow imaging and small-animal MRI were combined to monitor changes in blood flow on the brain surface of SD rats before and after the embolization in order to standardize ischemic timing and location.
In 1989, Longa et al. made a reversible MCA occlusion model by retrogradely inserting a self-made nylon suture into the external car...

Cerebral venous sinus thrombosis (CVST) is a rare disease of the cerebral venous system that accounts for only 0.5-1.0% of all causes of stroke but has a relatively high occurrence rate in children and young adults1. During autopsy, CVST was found to be the cause of 10% of cerebrovascular disease deaths2. Thrombosis can occur in any part of the intracranial venous system. The superior sagittal sinus (SSS) is one of the most commonly affected areas in CVST and can involve multiple blood vessels. Owing to stenosis or occlusion of the venous sinuses, intracranial venous return is blocked, which is often accompanied by increased intracranial pressure3. The clinical manifestations of CVST are complex and vary over time; although there is a lack of specificity of symptoms, the most common symptoms include headache (77.2%), seizures (42.7%), and neurological deficits (39.9%). In severe cases, coma and even death may occur4,5. In recent years, due to the overall improvement of medical and health standards and public health awareness, the proportion of related risk factors has changed, the proportion of trauma and infection has decreased, and the proportion of CVST caused by pregnancy, puerperium, oral contraceptives, and other reasons has gradually increased5.
At present, the pathogenesis of CVST is still not well understood. To explore CVST in depth, further pathophysiological research is needed. However, most of these research methods are invasive and therefore difficult to implement clinically. Owing to many limitations of clinical research, animal models have irreplaceable advantages in terms of basic and translational research.
The cause of CVST is complex, as its initial onset is often unrecognized and the location of thrombus formation is highly variable. Fortunately, animal models can achieve better control of these factors. In the past few decades, a variety of CVST animal models have been established, and each model has its own disadvantages. According to different production methods, they can be roughly divided into the following categories: the simple SSS-ligation model6,7; the SSS internal-injection-accelerator model8; the ferric-chloride-induced SSS thrombosis model9; the photochemical-induced SSS thrombosis model10; and the self-made embolism-occlusion SSS model11. However, most of these models are unable to circumvent invasive damage to the animal's cerebral cortex and are not able to accurately control the ischemic time and location. In some models, the thrombus will recanalize spontaneously; in other models, the SSS becomes permanently occluded. In addition, complicated operations and/or serious injuries may affect subsequent pathophysiological findings in these models.
In the present study, a thread plug was inserted into the SSS of Sprague-Dawley (SD) rats to successfully establish a CVST model that minimized damage, enabled precise controllability, and yielded good stability. Additionally, small-animal magnetic resonance imaging (MRI) and laser-speckle blood-flow imaging were combined to verify the model's effectiveness. We evaluated changes in cerebral blood flow before and after establishment of our model, as well as evaluated the stability of our model, laying a foundation for further studies exploring the occurrence, development, and related pathophysiological mechanisms of CVST.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>2 mL syringe</td>
			<td>Becton,Dickinson and Company</td>
			<td>301940</td>
			<td></td>
		</tr>
		<tr>
			<td>brain stereotaxic instrument</td>
			<td>Shenzhen RWD Life Technology Co., Ltd</td>
			<td>68025</td>
			<td></td>
		</tr>
		<tr>
			<td>dissecting microscope</td>
			<td>Wuhan SIM Opto-technology Co.</td>
			<td>SIM BFI-HR PRO</td>
			<td></td>
		</tr>
		<tr>
			<td>high-speed skull drill</td>
			<td>Shenzhen RWD Life Technology Co., Ltd</td>
			<td>78046</td>
			<td></td>
		</tr>
		<tr>
			<td>laser-speckle blood-flow imaging system</td>
			<td>Wuhan SIM Opto-technology Co.</td>
			<td>SIM BFI-HR PRO</td>
			<td></td>
		</tr>
		<tr>
			<td>needle holder</td>
			<td>Shenzhen RWD Life Technology Co., Ltd</td>
			<td>F31022-12</td>
			<td></td>
		</tr>
		<tr>
			<td>needle thread</td>
			<td>Shenzhen RWD Life Technology Co., Ltd</td>
			<td>F33303-08</td>
			<td></td>
		</tr>
		<tr>
			<td>scissors</td>
			<td>Shenzhen RWD Life Technology Co., Ltd</td>
			<td>S13029-14</td>
			<td></td>
		</tr>
		<tr>
			<td>silica gel</td>
			<td>Heraeus Kulzer</td>
			<td>302785</td>
			<td></td>
		</tr>
		<tr>
			<td>small animal anesthesia machine</td>
			<td>Shenzhen RWD Life Technology Co., Ltd</td>
			<td>R540</td>
			<td></td>
		</tr>
		<tr>
			<td>small-animal MRI</td>
			<td>Bruker Medical GmbH</td>
			<td>Biospec 94/30 USR</td>
			<td></td>
		</tr>
		<tr>
			<td>tweezers</td>
			<td>Shenzhen RWD Life Technology Co., Ltd</td>
			<td>F11029-11</td>
			<td></td>
		</tr>
		<tr>
			<td>vascular forceps</td>
			<td>Shenzhen RWD Life Technology Co., Ltd</td>
			<td>F22003-09</td>
			<td></td>
		</tr>
	</tbody>
</table>

establishment of a rat model of superior sagittal-sinus occlusion via a thread-embolism method

The mechanisms contributing to the natural onset of cerebral venous sinus thrombosis (CVST) are mostly unknown, and a variety of uncontrollable factors are involved in the course of the disease, resulting in great limitations in clinical research. Therefore, the establishment of stable CVST animal models that can standardize a variety of uncontrollable confounding factors have helped to circumvent shortcomings in clinical research. In recent decades, a variety of CVST animal models have been constructed, but the results based on these models have been inconsistent and incomplete. Hence, in order to further explore the pathophysiological mechanisms of CVST, it is necessary to establish a novel and highly compatible animal model, which has important practical value and scientific significance for the diagnosis and treatment of CVST. In the present study, a novel Sprague-Dawley (SD) rat model of superior sagittal sinus (SSS) thrombosis was established via a thread-embolization method, and the stability and reliability of the model were verified. Additionally, we evaluated changes in cerebral venous blood flow in rats after the formation of CVST. Collectively, the SD-rat SSS-thrombosis model represents a novel CVST animal model that is easily established, minimizes trauma, yields good stability, and allows for accurately controlling ischemic timing and location.

To establish the SD-rat SSS-thrombosis model via the suture method, the suture should be prepared in advance (Figure 1A), and the equipment required for the experiment (Figure 1B) should be prepared. Due to the delicate nature of the operation, the preparation of the model needs to be completed under a dissecting microscope. The main steps are shown in Figure 2. To facilitate the description of the specific details of the blood-flow...

Watch this Scientific Journal Video about Establishment of a Rat Model of Superior Sagittal-Sinus Occlusion via a Thread-Embolism Method at JoVE.com

Establishment of a Rat Model of Superior Sagittal-Sinus Occlusion via a Thread-Embolism Method

Here, we establish a novel Sprague-Dawley (SD) rat model of superior sagittal sinus (SSS) thrombosis via a thread-embolization method, and the stability and reliability of the model were verified.

The mechanisms contributing to the natural onset of cerebral venous sinus thrombosis (CVST) are mostly unknown, and a variety of uncontrollable factors ...

Due to the lack of an ideal animal model, the study of CVST is greatly limited. Now, a new type of SD-Rat CVST model was successfully established by inserting self-made thread-embolization centripetally at the initial site of SSS which standardized various or uncontrollable interference factors in clinical condition. After the rat was successfully anesthetized by intra peritoneal injection, apply gel ophthalmic eye lubricant after rat is put on stereotaxic frame to protect the corneas from drying during anesthesia.Remove the hair on the top of the rat's head. In order to perform this process more effectively the earlier step can be performed earlier in the preparation room. After the rat was successfully anesthetized by anesthetic machine, also apply sterile ophthalmic eye lubricant.Sterilize surface on top of the rat's head with 5%povidone iodine. Alternate this three times with 75%ethanol. Make a skin incision about two centimeters long in the middle of the head.The fascia is cut open with a scalpel. And then, carefully peel off the top fascia and the periosteum to fully expose the skull. Confirm the position of the anterior fontanelle, A and the posterior fontanelle, B.Use the area between the coronal suture and the elbow suture, as the blood flow observational area.To prevent the skull from affecting observation during laser-speckle blood flow imaging, thin the skull in the observation area until the blood vessels are clearly visible. During skull grinding use a normal temperature syringe to rinse the dura repeatedly, to avoid a high temperature burst to the cerebral cortex. This step and the following are all performed under a dissecting microscope.In this figure, the red lined rectangular area is the blood flow observation area. The size of the thinned skull should be approximately one centimeter multiplied by one centimeter. And the blue lined rectangular area is the bone window.About six millimeters multiplied by four millimeters. The red circular area is the parietal joint and the arrow points to the SSS. When the skull can be seen use tweezers to carefully the remaining bone pieces of the bone window.Choose a suitable thread probe, use the front point or as the plug point. Carefully puncture it with a 2 millimeter syringe needle and quickly insert a thread probe into the prep point. At this time, the angle between the end of the thread probe end and the SSS should be approximately 30 to 45 degrees.Then adjust the angle between the end of the thread probe and the SS to zero to 10 degrees. And slowly insert the SSS into the structure until the head reaches the posteria end of the sinus confluence. Rapid breathing may occur when the SSS is punctured.If the end of the thread probe cannot be quickly inserted into the prep point at one time use a small gauze or cotton ball to gently press the probe point while slowly sliding down to expose the prep point carefully. That is done, quickly insert to the end of the wire brought into the SSS. The blue arrow shows the state of the probe insert into the SSS from the plug point.White arrow shows the body of the probe and the red arrow shows that is the head. Thereafter cut off the excess part of the tail. Suture the rat's skin.Disinfect the skin three times and remove the rat from stereotaxic frame. Use the laser light source to uniformly illuminated the blood flow observational area. The image records the dynamic process of the thread probe into the SSS.In this figure A and B shows a comparison of blood flow before and after thread embolization insertion. C shows that the blood flow in the SSS and brain veins were decreased significantly compared with both in the middle cerebral artery and capillaries. Fix the animal on the MRI scanning table.Calibrate the brain position by positioning scanning and perform T2WI and MRI sequence scanning after confirming the position. In order to observe the state of the thread probe in the SSS more clearly the C2 head mounted method was used to display T2WI image of the rat brain. In this figure, A, B and C show the thread probe in the SSS from the horizontal position, sagittal position and the cranial position.The image shows that the thread probe is in place which confirms embolization of the SSS. As the rat SSS thrombosis model is easily established minimizing the trauma, offered good stability and allowed for accurately controlling the chemical timing and the location, it is an ideal new type of CVST model.

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3.3K visualizações.  the Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University. Devido à falta de um modelo animal ideal, o estudo do CVST é bastante limitado. Agora, um novo tipo de modelo CVST SD-Rat foi estabelecido com sucesso inserindo embolização de rosca auto-feita centripetally no local inicial da SSS que padronizou vários ou incontroláveis fatores de interferência em condição clínica. Depois que o rato foi anestesiado com sucesso por injeção intra peritoneal, aplique lubrificante ocular oftálmico de gel após o rato ser colocado em quadro estereotax...