Anterior communicating artery (AcomA) aneurysm is one of the most common intracranial aneurysms.Interventional treatment of wide-neck AcomA aneurysms remains challenging.With the emergence of several intracranial stents and the innovation and development of a variety of stent technologies,stentassisted coiling (SAC) embolization has gradually become one of the preferable techniques for the treatment of wide-neck AcomA aneurysms.This article reviews several SAC embolization techniques of AcomA aneurysms.

AIM: To investigate the differentiation of human mesenchymal stem cells (MSCs) into neuron-like cells induced by the supernatant of rat C6 glloma cells. METHODS: The heparin anticoagulant human bone marrow sampling was performed and human MSCs were separated flom human bone marrow using Percoll gradient method, followed by trypsinization and passage culture. When the MSCs at 4-6 passages reached a confluence of 90%, they were inoculated into a 24-well culture plate at a density of 2×103 per well. Cells were then divided into induction group and control group. In the induction group, C6 glioma cells were induced by the complete culture medium supplemented with 50% C6 glloma ceils supernatant (L-DMEM containing 0.1 fetal bovine serum), and half of the culture medium as replenished every 2 days. In the control group, cells were cultured in the complete culture medium. Both groups were treated 3 days and the expression of neuron-specific marker was monitored with S-P immunocytochemical stain. RESULTS: After an induction period of 24 hours, the differentiated MSCs showed typical neuron-like appearance, while the controlled cells exhibited no obvious alters. After 3 days of the induction, the neuron specific enola,se-positive rate of the cells in the induction was significantly higher than that in the control group (P < 0.01). The neurofilament protein-positive rate of cells in the induction group was (44.2±2.4)%, and the control group cells did not express neurofilament protein. Typical glial astrocyte marker glial fibrillary acidic protein was negatively expressed in both groups. CONCLUSION: Differentiation of MSCs into neuron-like cells can be induced by the supematant of rat C6 glioma cells in vitro.

MicroRNA (miRNA),which is closely related to the occurrence and development of tumors,may act as oncogenes or tumor suppressor genes by regulating target genes-related signal transduction pathways,such as epidermal growth factor receptor pathway,phosphatidylinositol 3-kinase-protein kinase B pathway and Ras signal transduction pathway.It is believed that miRNAs have broad application prospects in the treatment of tumors.

Objective To establish the carotid fusiform aneurysm model in rabbits carrying similar characteristics of human intracranial aneurysms by using induction method with porcine pancreatic elastase. Methods Twenty-five New Zealand white rabbits were randomly divided into normal control group (n=5), saline control group (n = 5) and study group (n = 15). The rabbits of the study group were randomly and equally subdivided into 7-day subgroup, 14-day subgroup and 21-day subgroup. By using induction method with porcine pancreatic elastase to digest right common carotid the fusiform aneurysm model was established in all the rabbits of the study group. DSA examination , HE staining and elastic fiber staining pathologic examination were carried out at 7, 14 and 21 days after the procedure to observe the imaging and pathologic changes of the fusiform aneurysm models. Results DSA angiography showed that the mean vascular diameters of the normal control group and the saline control group were (1.64 ± 0.17) mm and (1.66 ± 0.24) mm respectively. The mean length and width of the fusiform aneurysm of the 7-day subgroup, 14-day subgroup and 21-day subgroup were (19.33 ± 1.65) mm and (2.86 ± 0.21) mm, (19.66 ± 1.18) mm and (3.95 ± 0.54) mm, and (19.84 ± 0.82) mm and (4.03 ± 0.95) mm, respectively. Pathologically, rupture of internal elastic membrane, disordered structure of tunica media smooth muscle and distortion of cell shape were observed in the rabbits of 7-day subgroup. Gradually stabilized aneurysmal lumen intimal hyperplasia was seen in the rabbits of 14-day subgroup. Remarkable structure changes at the aneurysmal neck-cavity junction were found in the rabbits of 21-day subgroup. Elastic fiber staining demonstrated that strikingly thinned elastic layer was observed in the rabbits of 7-day subgroup, gradually thinning elastic layer at the aneurysmal neck-cavity junction was seen in the rabbits of 14-day subgroup, and the thinned elastic layer became stable in the rabbits of 21-day subgroup. Conclusion Using simple surgical method combined with porcine pancreatic elastase to digest vascular wall, carotid fusiform aneurysm models can be reliably established in New Zealand white rabbits which carry similar morphologic and pathologic characteristics of human intracranial aneurysms.

Objective To investigate the feasibility and effectiveness of inducing rabbit common carotid fusiform aneurysms via the common carotid extravascular digestion method. Methods Sixteen New Zealand white rabbits were randomly assigned into either an experiment group ( n=12 ) or a control group (n=4). Porcine pancreatic elastase 80-400 U were used to incubate and digest 2 to 4 cm segment of artery distal to the origin of right common carotid artery. One week after modeling,intravenous angiography was performed and the length and width of fusiform dilatation of common carotid artery were measured. The fusiform dilated artery was examined with hematoxylin and eosin staining and the vascular morphological changes were observed with scanning electron microscope. Isotonic saline solution was used to incubate common carotid arteries of the 4 New Zealand white rabbits in the control group. After one week,the same method was used to observe the lumen of common carotid artery and intimal changes. Results After the digestion of common carotid artery adventitia,the angiography of 12 New Zealand white rabbits of the experimental group revealed fusiform dilatation of common carotid artery of the 10 model rabbits. The widest diameter of the fusiform artery was 3. 70 ± 0. 32 mm;two rabbits had common carotid artery occlusion. Compared with the control group,the right common carotid artery diameter enlarged significantly in the experimental group (1. 80 ± 0. 16 mm,P<0. 01). The HE staining showed that the lumen widened, adventitia and media reduced. Scanning electron microscope showed intimal inflammatory injury and thrombus attachment. Conclusion Using porcine pancreatic elastase to digest the adventitia of common carotid artery can make fusiform dilatation of common carotid artery in rabbits. Using this method may effectively induce a model of fusiform aneurysm,and it has certain feasibility.

Objective To investigate the application technology and effect of Navien catheter in intracranial aneurysms embolization.Methods The clinical data of 15 patients with intracranial aneurysm treated with Navien catheter in Department of Neurosurgery of Yijishan Hospital Affiliated to Wannan Medical College from March to December 2016 were analyzed retrospectively. The extracranial segments of internal carotid arteries were seriously tortuous in all patients. The coaxial system was used during procedure. Whether the Navien catheter could be smoothly placed into the target artery or not was observed,and the coils or stent-assisted coils were used to embolize the intracranial aneurysms in the corresponding positions. The immediate embolization results were assessed by the Raymond grading. The intraoperative and postoperative complications were observed and the patients were followed up by imaging.Results All 15 patients had abnormal tortuosity of extracranial segments of internal carotid arteries. The Navien catheter was able to smoothly pass through the tortuous vessels and reach the desired position. The stent-assisted coil embolization was used in 9 patients,and the coil embolization was used in 6 patients. The success rate of the coil and stent placement technology was 100%. The stents were all accurately put in place without shift. According to the Raymond grading,the immediate embolization rate of aneurysms showed that 15 patients achieved Raymond gradeⅠ. One case developed internal carotid spasm during the procedure. The patient was improved after giving papaverine. Others did not have intraoperative complications,such as cerebral vasospasm,vascular dissection,in-stent thrombosis,and intraoperative aneurysm rupture. Five patients were followed up for 3 to 6 months with digital subtraction angiography (DSA). There was no recurrence of aneurysm and no in-stent stenosis and shift,No rebleeding or cerebral ischemia was observed.Conclusion Forpatients with severely tortuous in extracranial segments of internal carotid artery,using the Navien catheter may overcome artery tortuosity and other unfavorable factors of the patients and successfully reach the target vessel position,enable the embolization of intracranial aneurysms to be completed successfully.

Objective To investigate the effect of endovascular treatment of intracranial ruptured vertebral artery dissecting aneurysms via bilateral vertebral artery approach. Methods The symptoms and imaging results of 5 patients with ruptured vertebral artery dissecting aneurysms were analyzed retrospectively. They were all treated with coil embolization via bilateral vertebral artery approach. The two ends of dissection aneurysms were packed densely,the middle segments were packed loosely,and the arteries were isolated from the blood circulation. Results Of the 5 patients after treated,the clinical symptoms were improved rapidly in 4 patients no abnormal limbs activity and mental disorders. After treatment,the modified Rankin scale (mRS)was 0 in four cases after six-month follow-up. One patient turned clear consciousness after 4 weeks, and their mRS was 3 at 6-month follow-up. Before treatment,DSA showed vertebral artery dilation and stenosis. The mean length of involvement in vertebral arteries was 9. 3 ± 1. 5 mm;after treatment,the dissecting aneurysms of 5 patients did not develop completely,no further bleeding occurred,and no new infarcts were observed. No recurrence of the aneurysms and parent artery recanalization were found at the follow-up after 6 months. Conclusion The occlusion of ruptured vertebral artery dissecting aneurysms via bilateral vertebral artery approach is technically feasible. It may be an effective treatment to prevent rebleeding.

Objective To investigate the feasibility and effectiveness of endovascular treatment of posterior communicating artery aneurysm (PcoAA)in keeping the fetal posterior cerebral artery (FPCA) patency. Methods Form January 2014 to December 2015,14 patients with ruptured PcoAA enrolled retrospectively were treated with endovascular embolization. Six of them were treated with simple coil embolization,3 with stent-assisted coil embolization,3 with double catheter-assisted coil embolization,1 with stent-assisted coil embolization + double catheter technique,and 1 with Y-stent in Yijishan Hospital, Wannan Medical College. The immediate embolization rate of PcoAA (using Raymond grade),prognosis of the patients (the modified Rankin scale score at 6 months after procedure),complications,and imaging follow-up results were analyzed. Results The success rate of coil and stenting was 100% . All the stents were accurately released in place without displacement. The immediate Raymond grading of the aneurysms displayed that Raymond grade Ⅰ was in 8 cases,Raymond grade Ⅱ was in 4 cases,and Raymond grade Ⅲ was in 2 cases. All FPCA were kept patent. A coil protruded into internal carotid artery in one case during the procedure. Others did not have any complications,such as intraoperative cerebral vasospasm,in-stent thrombosis,and rupture. All 14 patients were followed up for 3 -24 months after procedure. Two had recurrence. Both were aneurysms embolized with coils only. No rebleeding and ischemic
complications were observed. The modified Rankin scale scores in 13 cases were 0 -2 at 6 months after procedure,1 was 4. Conclusions Endovascular embolization for the treatment of PcoAA and keeping FPCA patency are safe and feasible. A variety of endovascular treatment modalities are necessary in order to keep FPCA patency.

Objective To investigate the risk factors for influencing recrudescence after endovascular embolization of posterior communicating artery aneurysms.Methods From January 2014 to December 2014,71 consecutive patients (a total of 74 aneurysms) with posterior communicating artery aneurysm treated with endovascular treatment at the Department of Neurosurgery,Yijishan Hosptial of Wannan Medical College were enrolled retrospectively.The aneurysms were calculated as the number of cases (n=74).The aneurysms were divided into two groups according to whether they had recrudescence or not,including recurrent group (n=18) and non-recurrent group (n=56).The differences of the clinical data and aneurysm characteristics between the two groups were compared.Multivariate logistic regression was used to analyze the risk factors for recrudescence after endovascular embolization of posterior communicating artery aneurysms.Results Of the 74 patients with aneurysm,51 were treated with simple coil embolization and 23 were treated with stent-assisted coil embolization.All the coils were released satisfactorily.There were significant difference in the size of aneurysms and Raymond grade between the two groups (all P<0.01).The incidence of aneurysms with daughter cysts (55.6% [10/18] and the rate of non-stent-assisted coil embolization (88.9% [16/18]) in the recurrent group were significantly higher than those in the non-recurrent group (23.2% [13/56],62.5% [35/56]).The difference between the two groups was statistically significant (all P<0.05).There was no significant difference in other aneurysm features between the two groups (all P>0.05).After variable selection,the Raymond grade was referred to Raymond gradeⅠ.Multivariate logistic regression analysis showed that the non-stent-assisted coil embolization (OR,4.789,95%CI 1.207-19.009,P=0.026),Raymond grade Ⅱ (OR,12.326,95%CI 3.838-39.592,P<0.01),Raymond grade Ⅲ (OR,36.884,95%CI 2.892-470.454,P=0.005) were the independent risk factors for recrudescence after embolization of posterior communicating artery aneurysms.Conclusion Non-stent-assisted coil embolization,Raymond Ⅱ and Ⅲ may cause recrudescence of posterior communicating artery aneurysms.

Objective To analyze the intraoperative and postoperative common complications of Enterprise stent-assisted embolization of intracranial aneurysms and the causes and preventive measures. Methods One hundred forty-three patients with intracranial aneurysm treated with Enterprise stent-assisted embolization at the Department of Neurosurgery,Yijishan Hospital,the First Hospital Affiliated to Wannan Medical College from January 2012 to March 2014 were analyzed retrospectively. The common intraoperative and postoperative complications and its possible causes,as well as the appropriate management were analyzed,and the prognoses were observed. Results A total 143 patients(205 aneurysms)with intracranial aneurysm were enrolled,included 43 with unruptured aneurysm,12 with recurrent aneurysm,and 88 with ruptured aneurysm. A total of 170 Enterprise stents were used. Twenty-two patients (15. 4%)had complications. Among them,2 had intraoperative aneurysm rupture,and they recovered well and discharged after active treatment. Thirteen patients had acute thrombosis,11 of the patients completely restored blood flow immediately after tirofiban and/or urokinase,microcatheter and guidewire-contact thrombolysis. The thrombolysis failed in 1 patient,and the blood flow was slow in 1 patient. Six patients had different degrees of cerebral infarction after procedure,and 1 died (peroperative Hunt-Hess grade Ⅳ). Three patients had vasospasm and they were improved after reducing blood vessel wall irritation and papaverine infusion. The introperative stent guidewire was broken and the stent in place was difficult in 1 case. The last coil packed difficultly during the procedure,and it protruded into the parent artery in 1 case. Two patients had non-aneurysmal hemorrhage after procedure. After conservative treatment,one left unilateral limb muscle strength decline and the other was stable after craniotomy,but leaving aphasia and hemiplegia. Conclusion When using the Enterprise stent-assisted embolization for complex aneurysms,grasping the indications strictly,strengthening the perioperative management and improving the operative skills may reduce or avoid the occurrence of complications.