Therapeutic effects of different durations of acupuncture on rats with middle cerebral artery occlusion

Acupuncture is regarded as an effective therapy for cerebral ischemia. Different acupuncture ma- nipulations and durations may result in different therapeutic effects. In the present study, the Neig uan （PC6） acupoint of rats with occluded middle cerebral arteries was needled at a fixed frequency （3 Hz） with different durations, i.e., 5, 60 and 180 seconds under a twisting-rotating acupuncture method. Results showed that different durations of acupuncture had different therapeutic effects, with 60 seconds yielding a better therapeutic effect than the other two groups. This duration of treatment demonstrated rapid cerebral blood flow, encouraging recovery of neurological function, and small cerebral infarct volume. Experimental findings indicated that under 3 Hz frequency, the treatment of needling Neiguan for 60 seconds is effective for ischemic stroke.

Predictors of short-term outcome in patients with acute middle cerebral artery occlusion: unsuitability of fluid-attenuated inversion recovery vascular hyperintensity scores

Fluid-attenuated inversion recovery （FLAIR） vascular hyperintensity （FVH） is used to assess leptomeningeal collateral circulation, but clinical outcomes of patients with FVH can be very different. The aim of the present study was to assess a FVH score and explore its relationship with clinical outcomes. Patients with acute ischemic stroke due to middle cerebral artery M1 occlusion underwent magnetic resonance imaging and were followed up at 10 days （National Institutes of Health Stroke Scale） and 90 days （modified Rankin Scale） to determine short-term clinical outcomes. Effective collateral circulation indirectly improved recovery of neurological function and short-term clinical outcome by extending the size of the pial penumbra and reducing infarct lesions. FVH score showed no correlation with 90-day functional clinical outcome and was not sufficient as an independent predictor of short-term clinical outcome.

Screen-imaging guidance using a modified portable video macroscope for middle cerebral artery occlusion

The use of operating microscopes is limited by the focal length.Surgeons using these instruments cannot simultaneously view and access the surgical field and must choose one or the other.The longer focal length （more than 1 000 mm） of an operating telescope permits a position away from the operating field,above the surgeon and out of the field of view.This gives the telescope an advantage over an operating microscope.We developed a telescopic system using screen-imaging guidance and a modified portable video macroscope constructed from a Computar MLH-10 × macro lens,a DFK-21AU04 USB CCD Camera and a Dell laptop computer as monitor screen.This system was used to establish a middle cerebral artery occlusion model in rats.Results showed that magnification of the modified portable video macroscope was appropriate （5-20 ×） even though the Computar MLH-10 × macro lens was placed 800 mm away from the operating field rather than at the specified working distance of 152.4 mm with a zoom of 1-40 ×.The screen-imaging telescopic technique was clear,life-like,stereoscopic and matched the actual operation.Screen-imaging guidance led to an accurate,smooth,minimally invasive and comparatively easy surgical procedure.Success rate of the model establishment evaluated by neurological function using the modified neurological score system was 74.07%.There was no significant difference in model establishment time,sensorimotor deficit and infarct volume percentage.Our findings indicate that the telescopic lens is effective in the screen surgical operation mode referred to as ＂long distance observation and short distance operation＂ and that screen-imaging guidance using an modified portable video macroscope can be utilized for the establishment of a middle cerebral artery occlusion model and micro-neurosurgery.

Effect of Fujian tablet on the expression of Nogo-A mRNA in the cervical spinal cord of middle cerebral artery occlusion model rats

Inhibiting the expression of Nogo-A in cervical spinal cord by use of interaction of antigen and antibody can help the remodeling of corticospinal projection of focal cerebral ischemia model rats to facilitate neurological recovery, which provides a new possible mechanism for drugs to promote neurological recovery. However, the effects of drugs on the expression of Nogo-A in cervical spinal cord are still unclear. OBJECTIVE： To observe the effect of Fujian tablet on the expression of Nogo-A mRNA in cervical spinal cords of middle cerebral artery occlusion （MCAO） rats, and to investigate the possible regulatory effect of Fujian tablet on the regenerated microenvironment of spinal conduction bundle. DESIGN： A randomized and controlled trial taking Wistar rats as experimental animals. SETTING： Department of Neurology, Affiliated Hospital of Shandong University of Traditional Chinese Medicine. MATERIALS： This experiment was carried out in the laboratory of Shandong Academy of Medical Science between June 2005 and July 2006. A total of 40 healthy male Wistar rats, aged 12 weeks, weighing 250 - 300 g, were provided by the Experimental Animal Center of Shandong University. Fujian tablets （main components： Heshouwu, Yinyanghuo, etc） were provided by office of Pharmaceutics of Shandong University of traditional Chinese medicine. Nogo-A detection kit was provided by Wuhan Boster Biotechnology Co.,Ltd., and batch number was 040309009. This experiment was approved by Local Animal Ethics Committee. METHODS： Forty male rats were randomly divided into 4 groups, with 10 in each： normal group, sham-operation group, model group and administration group. Rats in the administration group and model group were subjected to MCAO. Rats in the sham-operation group underwent the same craniotomy, and their middle cerebral arteries （MCA） were not occluded. Rats in the normal group were untouched. Rats in administration group were intragastrically administrated with the solution of Fujian tablet at a dose of 9 g/kg and others were given equal dosage of normal saline two days later. The treatments were done once a day and the course totaled 2 weeks. MAIN OUTCOME MEASURES： The expression of Nogo-A mRNA in slices of cervical spinal cords. RESULTS： Forty rats were involved in the final analysis. The expression of Nogo-A mRNA in the cervical spinal cord of rats in the administration group and model group was significantly decreased as compared with that in the normal group （P 〈 0.01 and P 〈 0.05, respectively）. The expression of Nogo-A mRNA in the administration group was also significantly weaker than that in the model group （P 〈 0.05 ） . CONCLUSION： Fujian tablet can inhibit the expression of Nogo-A mRNA in cervical spinal cords of MCAO rats, which facilitates regeneration and remodeling of cervical spinal cords.

Motor outcomes of patients with a complete middle cerebral artery territory infarct

Detailed knowledge of motor outcomes enables to establish proper goals and rehabilitation strate-gies for stroke patients. Several previous studies have reported functional or motor outcomes in patients with a middle cerebral artery territory infarct. However, little is known about motor outcome in patients with a complete middle cerebral artery territory infarct. In this study, we investigated the motor outcomes in 23 patients with a complete middle cerebral artery territory infarct. All of these patients received comprehensive rehabilitative management, including movement therapy and neuromuscular electrical stimulation of the affected finger extensors and ankle dorsiflexors, for more than 3 months. Motor outcomes were measured at 6 months after stroke onset using the Medical Research Council, Motricity Index, the modified Brunnstrom Classification, and Functional Ambula-tion Category scores. The motor function of the lower extremities was found to be better than that of the upper extremities. After receiving rehabilitation treatments for 3–6 months, about 70% of these patients were able to walk independently （Functional Ambulation Category scores 3）, but no pa-tient achieved functional hand recovery.

Is decompressive craniectomy for malignant middle cerebral artery infarction of any worth?

Objective: Malignant middle cerebral artery (MCA) infarction is characterized by mortality rate of up to 80%. The aim of this study was to determine the value of decompressive craniectomy in patients presenting malignant MCA infarction compared with those receiving medical treatment alone. Methods: Patients with malignant MCA infarction treated in our hospital between January 1996 and March 2004 were included in this retrospective analysis. The National Institute of Health Stroke Scale (NIHSS)was used to assess neurological status on admission and at one week after surgery. All patients were followed up for assessment of functional outcome by the Barthel index (BI) and modified Rankin Scale (RS) at 3 months after infarction. Results: Ten out of 24patients underwent decompressive craniectomy. The mean interval between stroke onset and surgery was 62.10 h. The mortality was 10.0% compared with 64.2% in patients who received medical treatment alone (P<0.001). The mean NIHSS score before surgery was 26.0 and 15.4 after surgery (P<0.001). At follow up, patients who underwent surgery had significantly better outcome with mean BI of 53.3, RS of 3.3 as compared to only 16.0 and 4.60 in medically treated patients. Speech function also improved in patients with dominant hemispherical infarction. Conclusion: Decompressive craniectomy in patients with malignant MCA infarction improves both survival rates and functional outcomes compared with medical treatment alone. A randomized controlled trial is required to substantiate those findings.

Surgical Treatment of Poor Grade Middle Cerebral Artery Aneurysms Associated with Large Sylvian Hematomas Following Prophylactic Hinged Craniectomy

The clinical characteristics of patients who presented in poor clinical grade due to ruptured middle cerebral artery aneurysms （MCAAs） associated with large sylvian hematomas （SylH） were ana- lyzed and an ingenious designed prophylactic hinged craniectomy was introduced. Twenty-eight pa- tients were graded into Hunt-Hess grades IV-V and emergency standard micro-neurosurgeries （aneu- rysm clipping, hematoma evacuation and prophylactic hinged craniectomy） were performed, and their clinical data were retrospectively analyzed. 46.43% of the patients reached encouraged favorable out- comes on discharge. The favorable outcome group and the poor outcome group significantly differed in terms of patients＇ anisocoria, Hunt-Hess grade before surgery, extent of the midline shift and time to the surgery after bleeding （P〈0.05）. There were no significant differences in age, sex, volume and location of the hematoma, size of aneurysm between the favorable and poor groups （P〉0.05）. However, ingen- ious designed prophylactic hinged craniectomy efficiently reduced the patients＇ intracranial pressure （ICP） after surgery. It was suggested that preoperative conditions such as Hunt-Hess grading, extent of the midline shift and the occurrence of cerebral hernia affect the prognosis of patients, but time to the surgery after bleeding and prophylactic hinged craniectomy are of significant importance for optimizing the prognosis ofMCAA oatients 19resenting with large SylH.

In vivo tracking of human adipose-derived stem cells labeled with ferumoxytol in rats with middle cerebral artery occlusion by magnetic resonance imaging

Ferumoxytol, an iron replacement product, is a new type of superparamagnetic iron oxide ap- proved by the US Food and Drug Administration. Herein, we assessed the feasibility of tracking transplanted human adipose-derived stem cells labeled with ferumoxytol in middle cerebral artery occlusion-injured rats by 3.0 T MRI in vivo. 1 × 104 human adipose-derived stem cells labeled with ferumoxytol-heparin-protamine were transplanted into the brains of rats with middle cerebral artery occlusion. Neurologic impairment was scored at 1, 7, 14, and 28 days after transplantation. T2-weighted imaging and enhanced susceptibility-weighted angiography were used to observe transplanted cells. Results of imaging tests were compared with results of Prussian blue staining. The modified neurologic impairment scores were significantly lower in rats transplanted with cells at all time points except I day post-transplantation compared with rats without transplantation. Regions with hypointense signals on T2-weighted and enhanced susceptibility-weighted angiography images corresponded with areas stained by Prussian blue, suggesting the presence of superparamagnetic iron oxide particles within the engrafted cells. Enhanced susceptibility-weighted angiography image exhibited better sensitivity and contrast in tracing ferumoxytol-heparin-protamine-labeled human adipose-derived stem ceils compared with T2-weighted imaging in routine MRI.

Apparent diffusion coefficient evaluation for secondary changes in the cerebellum of rats after middle cerebral artery occlusion

Supratentorial cerebral infarction can cause functional inhibition of remote regions such as the cerebellum, which may be relevant to diaschisis. This phenomenon is often analyzed using positron emission tomography and single photon emission CT. However, these methods are expensive and radioactive. Thus, the present study quantified the changes of infarction core and remote regions after unilateral middle cerebral artery occlusion using apparent diffusion coefficient values. Diffu- sion-weighted imaging showed that the area of infarction core gradually increased to involve the cerebral cortex with increasing infarction time. Diffusion weighted imaging signals were initially in- creased and then stabilized by 24 hours. With increasing infarction time, the apparent diffusion co- efficient value in the infarction core and remote bilateral cerebellum both gradually decreased, and then slightly increased 3-24 hours after infarction. Apparent diffusion coefficient values at remote regions （cerebellum） varied along with the change of supratentorial infarction core, suggesting that the phenomenon of diaschisis existed at the remote regions. Thus, apparent diffusion coefficient values and diffusion weighted imaging can be used to detect early diaschisis.

Viscoelastic evaluation of fetal umbilical vein for reconstruction of middle cerebral artery

The transplantation of artificial blood vessels with 〈 6 mm inner diameter as substitutes for human arterioles or veins has not achieved satisfactory results. Umbilical vein has been substituted for ar- tery in vascular transplantation, but it remains unclear whether the stress relaxation and creep be- tween these vessels are consistent. In this study, we used the fetal umbilical vein and middle cere- bral artery from adult male cadavers to make specimens 15 mm in length, 0.196-0.268 mm in tu- nica media thickness, and 2.82-2.96 mm in outer diameter. The results demonstrated that the stress decrease at 7 200 seconds was similar between the middle cerebral artery and fetal umbilical vein specimens, regardless of initial stress of 18.7 kPa or 22.5 kPa. However, the strain increase at 7 200 seconds of fetal umbilical veins was larger than that of middle cerebral arteries. Moreover, the stress relaxation experiment showed that the stress decrease at 7 200 seconds of the fetal umbilical vein and middle cerebral artery specimens under 22.5 kPa initial stress was less than the decrease in these specimens under 18.7 kPa initial stress. These results indicate that the fetal umbilical vein has appropriate stress relaxation and creep properties for transplantation. These properties are advantageous for vascular reconstruction, indicating that the fetal umbilical vein can be transplanted to repair middle cerebral artery injury.

Establishment of a rhesus monkey model of middle cerebral artery ischemia and reperfusion using a microcatheter embolization method

Nonhuman primates are closest to humans in terms of lineage, and middle cerebral artery ischemia/reperfusion responses of nonhuman primates are most similar to ischemic stroke in humans. Therefore, nonhuman primates could be utilized to simulate the process of ischemic stroke in the human. Few studies, however, have reported the use of endovascular technology to establish a rhesus monkey stroke model. In the present study, seven adult, male, rhesus monkeys were selected and, following anesthesia, a microcatheter was inserted into one side of the middle cerebral artery via the femoral artery to block blood flow, thereby resulting in middle cerebral artery occlusion. After 2 hours, the microcatheter was withdrawn to restore the middle cerebral artery blood flow and to establish ischemia/reperfusion. Results from angiography and magnetic resonance angiography confirmed occlusion and reopening of the middle cerebral artery. Magnetic resonance imaging revealed the existence of ischemic brain lesions, and neurological examination showed sustained functional deficits following surgery. The rhesus monkey middle cerebral artery ischemia/reperfusion models established by microcatheter embolization had the advantage of non-craniotomy invasion and reproducibility. The scope and degree of ischemic damage using this model was controllable. Therefore, this nonhuman primate model is an ideal model for cerebral ischemia and reperfusion.

Effects of Echinacoside on Histio-central Levels of Active Mass in Middle Cerebral Artery Occlusion Rats

Objective To investigate the effects of echinacoside on the extracellular striatal levels of norepinephrine（NE）,dopamine（DA）,homovanillic acid（HVA）,3,4-dihydroxyphenylethanoid acid（DOPAC）,5-hydroxyindoleacetic acid（HIAA）,and 5-hydroxytryptamine（5-HT） in middle cerebral artery occlusion（MCAO rats.Methods The middle cerebral artery was occluded in male Sprague-Dawley rats.Three days later microdialysis probes were placed into the right striatum of MCAO rat brains and the brains were perfused with Ringer＇s solution at a rate of 1.5 μL/min.Cerebral microdialysates were collected every 30 minutes from awake and freely moving rats before assaying for NE,DA,HVA,DOPAC,HIAA,and 5-HT levels by reverse phase HPLC with electrochemistry.Results Three days after MCAO,the extracellular striatal levels of NE,DA,DOPAC,HIAA,HVA,and 5-HT of the MCAO rats increased significantly（at least P0.05 vs.control）.However,simultaneous treatment with echinacoside（30.0 or 15.0 mg/kg） attenuated these increases（at least P0.05 vs.non-treated model rats）.Conclusion These results imply that echinacoside may protect striatal dopa minergic neurons from the injury induced by MCAO and may help prevent and treat cerebral ischemic diseases.

Significance of Cyclooxygenase-2 Elevation in Middle Cerebral Artery for Patients with Hemorrhagic Moyamoya Disease

The etiology and pathogenesis of moyamoya disease（MMD） remain elusive. Some inflammatory proteins, such as cyclooxygenase（COX）-2, are believed to be implicated in the development of MMD. So far, the relationship between COX-2 and MMD is poorly understood and reports on the intracranial vessels of MMD patients are scanty. In this study, tiny pieces of middle cerebral artery（MCA） and superficial temporal artery（STA） from 13 MMD patients were surgically harvested. The MCA and STA samples from 5 control patients were also collected by using the same technique. The expression of COX-2 was immunohistochemically detected and the average absorbance（A） of positively-stained areas was measured. High-level COX-2 expression was found in all layers of the MCA samples from all 5 hemorrhagic MMD patients, while positive but weak expression of COX-2 was observed only in the endothelial layer of the MCA samples from most ischemic MMD patients（6/8, 75%）. The average A values of COX-2 in the hemorrhagic MMD patients were substantially higher than those in their ischemic counterparts（t=4.632, P=0.001）. There was no significant difference in the COX-2 expression among the ＂gender＂ groups, or ＂radiographic grade＂ groups, or ＂lesion location＂ groups（P0.05 for all）. The COX-2 expression was detected neither in the MCA samples from the controls nor in all STA specimens. Our results suggested that COX-2 was up-regulated in the MCA of MMD patients, especially in hemorrhagic MMD patients. We are led to speculate that COX-2 may be involved in the pathogenesis of MMD and even contribute to the hemorrhagic stroke of MMD patients.

Neuroprotective effect of Longshengzhi capsule following permanent middle cerebral artery occlusion in rats

Objective:Longshengzhi capsule(LSZC)is an optimized preparation based on the traditional Chinese Medicine formula Buyanghuanwu Decoction(BYHWD),and is approved by the China Food and Drug Administration for treating stroke-induced disability and vascular diseases.Herein,we examined the pharmacodynamics,anti-apoptotic and anti-oxidant actions,and potential mechanisms of action of LSZC following stroke in rats.Methods:Permanent middle cerebral artery occlusion(MCAO)was used as an ischemic stroke model.LSZC was administered intragastrically.We examined the survival rate,bodyweight,and neurological deficits in stroke rats.Brain infarct size was determined by 2,3,5-triphenyltetrazolium chloride staining.Brain pathology was examined using hematoxylin and eosin staining,Nissl staining,and TdT-mediated dUTP Nick-End Labeling staining.Malondialdehyde,catalase,superoxide dismutase,and glutathione levels were examined by commercial kits.Expression of Nrf2,heme oxygenase-1,Bax,Bcl-2,cleaved caspase-3,and caspase-3 proteins in brain tissue was measured by Western blot.Results:LSZC markedly improved the survival rate and bodyweight,and reduced infarct volume and neurological deficit scores,in MCAO stroke rats.LSZC also significantly attenuated oxidative stress,as indicated by decreased expression of malondialdehyde,and upregulation of Nrf2,heme oxygenase-1,catalase,superoxide dismutase,and glutathione.Moreover,LSZC significantly decreased apoptosis,including a decrease in Bax and cleaved caspase-3 expression,and an increase in Bcl-2,as well as a reduction in numbers of apoptotic neurons.Conclusion:LSZC treatment is neuroprotective against ischemic stroke,potentially via reducing oxidative stress and apoptosis.The Nrf2 and apoptotic signaling pathways may play important roles in the antioxidant and anti-apoptotic actions of LSZC.

Intraoperative hemodynamic parameters of middle cerebral artery and other artery aneurysms utilizing transcranial Doppler ultrasonography

BACKGROUND： Hemodynamic changes accompany the initiation, development and rupture of middle cerebral artery （MCA） aneurysms. The complexity of the intraaneurysmal hemodynamic factors has not been completely clarified by the indirect measures and methods used in previous studies. OBJECTIVE： To evaluate correlations of intraoperative hemodynamic factors to initiation and rupture of MCA aneurysms. DESIGN, TIME AND SETTING： A case-control study was performed at the Department of Neurosurgery, Tiantan Hospital Affiliated to Capital Medical University, China between March and October 2008. PARTICIPANTS： A total of 12 consecutive patients diagnosed with MCA aneurysms （MCA aneurysms group） and five patients without middle cerebral artery aneurysms （with aneurysms located at other arteries, control group） were enrolled at the Department of Neurosurgery, Tiantan Hospital Affiliated to Capital Medical University, China. METHODS： The proximal and distal arteries of MCA aneurysms were exposed visibly in the MCA aneurysm group. The M1 segment of MCA without the aneurysm and the aneurysm on other arteries were also exposed visibly in the control group. Hemodynamic indices were then measured using an intraoperative 16 MHz probe installed in a Multi-Dop TCD8X4 device. MAIN OUTCOME MEASURES： Mean （time-averaged velocity） difference, maximum mean, pulsatility index difference, maximum pulsatility index, resistance index difference, maximum resistance index; correlation of development and rupture of MCA aneurysms to intraoperative hemodynamic factors of the parent artery. RESULTS： A total of 12 patients underwent microsurgery for treatment to occlude 15 MCA aneurysms. Of the 15 MCA aneurysms, 12 were located at the bifurcation, two at the M1 segment and one at the M3 segment; eight of the aneurysms were unruptured and seven were ruptured. The whole indices with combination mean difference, maximum mean, and maximum pulsatility index of the aneurysms were important factors influencing the rupture of MCA aneurysms （t = 2.92, P = 0.03, constant）. A higher velocity intraaneurismal flow at the bifurcation was identified （t = 3.48, P = 0.01, constant）. After the aneurysm was completely occluded, global high-velocity flow could not be detected in the parent arteries （t = 2.57, P=0.03, constant）. CONCLUSION： When short-term high-velocity blood flow is present, aneurysms can be easily initiated and ruptured at the bifurcation of MCA.

Fetal umbilical vein transplantation for the repair of middle cerebral artery injury

It is necessary to investigate the longitudinal tensile mechanical characteristics of the middle cere- bral artery and the fetal umbilical vein prior to applying fetal umbilical vein transplantation for repair of injured middle cerebral artery. Fifteen fresh fetal umbilical vein specimens and 15 normal human fresh cadaver middle cerebral artery specimens were collected for longitudinal tensile testing at the speed of 0.5 mm/min and at normal human temperature. The results showed that under 16.0 kPa physiological stress, the strain value of fetal umbilical vein specimens was larger, while the maximal stress and elastic modulus values were less than those of middle cerebral artery specimens. Our findings indicate that fetal umbilical vein has good elastic properties and the stress-strain curve of the fetal umbilical vein is similar to that of the middle cerebral artery. Fetal umbilical vein transplan- tation can, therefore, potentially repair the injured middle cerebral artery.

Occlusion of the middle cerebral artery Guidance by screen imaging using an EDA-H portable medium-soft electronic endoscope

The present study aimed to verify the practicability of performing screen-based surgical operations under the guidance of a real-time viewing and recording system （RTVRS） using a portable medium-soft electronic endoscope （pmsEE）. The middle cerebral artery in rats was occluded under screen-imaging guidance using a pmsEE RTVRS to reproduce an animal model of human cerebral infarction. The screen imaging of the pmsEE RTVRS was clear, life-like, stereoscopic and synchronous with the actual operation. Screen-imaging guidance led to an accurate, smooth, minimally invasive and comparatively easy surgical procedure. The surgical success rate, time of model establishment, neurological function scores, and infarct volume were similar to those using an operating microscope. These results indicate that the self-designed pmsEE RTVRS could be utilized for portable endoscopic screen-based surgical operations.

Histopathological Features of Middle Cerebral Artery and Superficial Temporal Artery from Patients with Moyamoya Disease and Enlightenments on Clinical Treatment

The histopathological features of the middle cerebral artery（MCA） and superficial temporal artery（STA） from moyamoya disease（MMD） and their relationships with gender,age,angiography stage were explored.The causes and the clinical significance of vasculopathy of STA were also discussed.The clinical data and specimens of MCA and STA from 30 MMD patients were collected.Twelve samples of MCA and STA from non-MMD patients served as control group.Histopathological examination was then performed by measuring the thickness of intima and media,and statistical analysis was conducted.The MCA and STA specimens from MMD group had apparently thicker intima and thinner media than those from the control group.There was no significant pathological difference between the hemorrhage group and non-hemorrhage group,and between the males and females in MMD patients.Neither the age nor the digital subtraction angiography（DSA） stage was correlated with the thickness of intima in MCA and STA.MMD is a systemic vascular disease involving both intracranial and extracranial vessels.Preoperative external carotid arteriography,especially super-selective arteriography of the STA,benefits the selection of donor vessel.

Middle cerebral artery occlusion methods in rat versus mouse model of transient focal cerebral ischemic stroke

Experimental stroke research commonly employs focal cerebral ischemic rat models （Bederson et al., 1986a; Longa et al., 1989）. In human patients, ischemic stroke typically results from thrombotic or embolic occlusion of a major cerebral artery, usually the mid- dle cerebral artery （MCA）. Experimental focal cerebral ischemia models have been employed to mimic human stroke （Durukan and Tatlisumak, 2007）. Rodent models of focal cerebral ischemia that do not require craniotomy have been developed using intraluminal suture occlusion of the MCA （MCA occlusion, MCAO） （Rosamond et al., 2008）. Furthermore, mouse MCAO models have been wide- ly used and extended to genetic studies of cell death or recovery mechanisms （Liu and McCullough, 2011）. Genetically engineered mouse stroke models are particularly useful for evaluation of isch- emic pathophysiology and the design of new prophylactic, neuro- protective, and therapeutic agents and interventions （Armstead et al., 2010）. During the past two decades, MCAO surgical techniques have been developed that do not reveal surgical techniques for mouse MCAO model engineering. Therefore, we compared MCAO surgical methods in rats and mice.

Combined surgical and interventional treatment of tandem carotid artery and middle cerebral artery embolus: A case report

BACKGROUND The 2018 American Heart Association/American Stroke Association guidelines for early management of acute ischemic stroke recommend the use of retrievable stents for mechanical thrombectomy in patients with acute internal carotid artery or middle cerebral artery M1 occlusion that can be treated within 6 h from onset.For cases of carotid artery with ipsilateral middle cerebral artery tandem embolization, the operation is more complicated and challenging. We here report a case of a tandem embolism, and the anatomy of the aortic arch was complex.Direct carotid artery incision and thrombectomy can not only prevent the escape of the carotid embolus but also save time during establishment of the thrombectomy access.CASE SUMMARY The patient was a 70-year-old man. He was admitted to hospital due to sudden inability to speak and inability to move his right limb for 3 h. Imaging confirmed a diagnosis of a tandem embolism in the left carotid artery with left M1 occlusion.Carotid artery incision thrombectomy combined with stent thrombectomy was performed. The operation was successful, and 24 h later the patient was conscious and mentally competent but had motor aphasia. His bilateral limb muscle strength level was 5, and his neurologic severity scores score was 2.CONCLUSION Carotid artery incision thrombectomy combined with stenting for carotid artery plus cerebral artery tandem embolization is clinically feasible. For patients with a complicated aortic arch and an extremely tortuous carotid artery, carotid artery incision can be chosen to establish the interventional path.