Volume 33 · Issue 04 · 2017

At present, stroke is still one of the main disabling and fatal diseases in all countries in the world. According to the Third Retrospective Sampling Survey Report of Causes of Death in China, stroke has become the first cause of death among Chinese nationals, and the mortality rate is 4~5 times that of European and American countries and 3.5 times that of Japan. In the United States, one stroke occurs every 40 seconds and one stroke dies every 4 minutes^[1]。 According to the "China Stroke Prevention and Treatment Report 2015", the overall standardized prevalence of stroke in China is 2.1%, and about 16.4% of people aged ≥40 are at high risk of stroke, and 10% to 15% of strokes are caused by carotid artery stenosis^[2]。 According to this estimate, at least 3.5 million stroke patients in China are caused by carotid artery stenosis. When to undergo carotid revascularization in these patients after stroke has become an urgent clinical problem to be standardized.

To evaluate the safety and efficiency of endovascular Willis covered stent in treating ruptured blood blister-like aneurysms (BBAs) of supraclinoidal internal carotid artery.

During the period from December 2013 to December 2015, 13 patients with 15 ruptured BBAs of supraclinoidal internal carotid artery were treated with Willis covered stentsin Department of Interventional Radiology of Tongji Hospital affiliated to Tongji University. We retrospectively analyzed the patients'clinical data, endovascular treatment, surgicaloutcomes, complications and follow-up results.

Thirteen stents were successfully delivered in thirteen patients with fifteen aneurysms. Immediate angiography after stent deployment revealed complete occlusion in 12 patients and minorendoleak in 1 patient, which had spontaneously resolved at the follow-up.In addition, occlusion of the ophthalmic artery was observedin 2 cases and occlusion of the anterior choroidal artery was demonstratedin 1 case without neurological dysfunctions. During the operation, no acute thrombosis, aneurysm rupture or other complications occurred in those patients. The mean follow-up period was 5.5±0.8 months (range 4-6 months). The follow-up angiography showed no stenosis in the parent arteryor aneurysm recurrence. Only two patients had mild to moderate asymptomatic in-stent stenosis. During the follow-up period, no bleeding or ischemic events were reported. The modified Rankin Scale was 0 in 8 patients and 1 in 5 patients.

Willis covered stentseems to be safe and effective for the treatment of ruptured BBAs of superclinoid internal carotid artery, which needs to be confirmedby longer follow-up and large-sample controlled studies.

To evaluate the technical feasibility, safety and long-term outcome of interventional recanalization for chronic symptomatic intracranial vertebrobasilar artery occlusion (VBAO), and to summarize the collateral circulations for chronic VBAO.

A retrospective study was conducted about 13 consecutive patients with chronic VBAO on the dominant side who were admitted to Department of Interventional Neurology, Beijing Tiantan Hospital, Capital Medical University during the period from January of 2013 to December of 2015 and underwent interventional recanalization. The rate of recanalization, collateral circulation, periprocedural complications and follow-up results were evaluated. The Thrombolysis in Cerebral Infarction (TICI) score was compared radiographically before and after procedure and the functional outcome was assessed based on the modified Rankin Scale (mRS).

In this series, recanalization was successful in 11/13 patients immediately after the procedure. In 3 patients, more than 1 stent was applied because of the long lesions (3 stents in 1 patient and 2 stents in the other 2 patients). The balloon angioplasty only was conducted in 2 patients. One patient developed the perioperative complication of perforator stroke confirmed with MRI. At 21-month follow-up, 11 patients reported good outcome (mRS score: 0-1). One patient had moderate (mRS socre: 2-3) and one had poor outcome (mRS score: 4-5). No death occurred. Collateral circulations for VBAO included posterior communicating artery (n=8), cerebellar leptomeningeal artery (n=8), anterior spinal arteries (n=3) and leptomeningeal artery flow from middle cerebral artery to posterior cerebral artery (n=2).

Endovascular recanalization for symptomatic chronic VBAO seems to demonstrate technical feasibility and safety for particular patients, which, however, needs further clinical research considering it may be associated with certain rates of perioperative complications.

To investigate the factors influencing the complications and prognosis of stent-assisted coil embolization (SACE) for ruptured wide-necked saccular intracranial aneurysms.

A retrospective analysis was conducted about the clinical data of 147 patients with ruptured wide-necked saccular intracranial aneurysms who underwent SACE from March 2008 to December 2015 at Department of Neurosurgery, Nanjing General Hospital of Nanjing Military Command. The modified Rankin Scale (mRS) was used to assess the patients’ outcomes. Univariate and multivariate Logistic regression were utilized to identify the factors influencing the related complications and prognosis.

Surgery-related complications occurred in 26 patients (17.7%) out of 147 cases. The location (P=0.002) and size (P=0.028) of intracranial aneurysms might be risk factors of the complications. Among all patients, 125(85.0%) achieved good clinical outcome. The univariate analysis revealed that the patient's age over 65 (P=0.041) and relatively high Hunt-Hess grade at admission (P<0.001) might be associated with high mRS at the time of discharge. The analysis using multivariate Logistic regression demonstrated that the Hunt-Hess grade (OR, 28.790, 95% CI 8.091-102.446, P<0.001) and aneurysm size (OR, 0.149, 95% CI 0.030-0.734, P=0.019) were independent factors influencing the patient's mRS at the time of discharge, while the short-term outcome was only associated with the Hunt-Hess grade(P<0.001).

The treatment of SACE seems to be a safe and effective procedure for ruptured wide-necked saccular intracranial aneurysms. Middle cerebral artery aneurysms and large aneurysms might be the risk factors of surgical complications. The patient's age over 65, high Hunt-Hess grade on admission and large size of aneurysm could be associated with poor outcome at the time of discharge assessed by mRS. High Hunt-Hess grade might be a significant factor influencing the patient's short-term prognosis.

To observe the short-term efficacy of Pipeline embolization device (PED) for the treatment of complex intracranial aneurysms.

The clinical data of 27 consecutive patients with 28 intracranial aneurysms treated with PED at Department of Neurosurgery the First Hospital of Xinjiang Medical University between April 2015 to July 2016 were analyzed retrospectively. PED were implanted in 10 out of the 27 patients, PED combined with coils in 17 patients, and 2 patients underwent balloon remodeling following PED implantation.

We treated 27 aneurysms with 28 PEDs, all of which were successfully implanted. PED were placed across the ostia of 17 ophthalmic arteries, 9 posterior communicating arteries, 4 posterior inferior cerebellar arteries and 1 anterior cerebral artery. Immediate post-procedural angiography revealed occlusion in 1 (1/17) ophthalmic artery and 1 (1/9) posterior communicating artery, and no occlusion of branch vessels or stenosis of parent arteries occurred. Two cases of subarachnoid hemorrhage resulting in death occurred 2 hours and 5 days post surgery, respectively. At 6-month follow-up, 19 patients underwent whole-brain angiography and 4 patients received the examination of MRA, which revealed complete occlusion or near occlusion in 20 (87%, 20/23) cases as well as partial occlusion in 3 (13%, 3/23) cases without any stenosis of parent arteries. The branch arteries without immediate intraoperative occlusion remained well. No neurological deficits were reported in 25 patients who received clinical follow-up.

The PED seems to demonstrate a good short-term effect on the treatment of complex intracranial aneurysms with high rates of aneurysm occlusion and low risk of complications.

To investigate the efficacy and safety of antiplatelet therapy with tirofiban in stent-assisted embolization of intracranial aneurysms.

The clinic data of 309 patients with intracranial aneurysms were retrospectively studied, who were admitted to Wuhan General Hospital of People's Liberation Army of China from January 2014 to December 2015 and treated with stent-assisted embolization. The cases included 213 ruptured aneurysms and 79 unruptured aneurysms. After successful stenting, tirofiban was administered with intravenous bolus injection [2-4 μg/kg (about 2-4 ml)], continuously infused with pump for 24 hours and followed by gradual switch to oral administration of platelet aggregation inhibitors.

In the 309 patients with intracranial aneurysms, complications that occurred during the application of tirofiban included rerupture of aneurysms in 6 cases (1.9%), thrombosis in 2 cases (0.6%) and bleeding in trachea carina in 1 case (0.3%). Among them, 298 cases had successfully transitioned from tirofiban to oral platelet aggregation inhibitors 12-24 hours post surgery. For 76 patients, there was significant difference in the average rate of platelet activation between preoperative and 1-day postoperative (CD62p) levels 75.7±10.4% vs. 71.9±15.9%, respectively, P=0.035). For 133 patients, there was also significant difference in the average rate of platelet activation between preoperative and 3-day postoperative levels 73.2±13.2% vs. 27.9±22.1%, respectively, P<0.001).

Antiplatelet threapy with tirofiban for patients with stent-assisted embolization of intracranial aneurysms is relatively safe and effective, but cautions need to be taken in cases with hemorrhagic tendency. The platelet activation test could objectively reveal the inhibition of platelets and help guide the clinical administration of platelet aggregation inhibitors.

To investigate the effects of surgical timing and approaches on the treatment outcomes of hypertensive cerebral hemorrhage in the basal ganglia.

The clinical data of 223 patients with hypertensive cerebral hemorrhage in the basal ganglia, who underwent operations at Department of Neurosurgery, the People's Hospital of Xinjiang Uygur Autonomous Region from January 2010 to September 2015, were retrospectively analyzed. Based on the time from illness onset to surgery, these patients were divided into 3 groups: the ultra-early group (≤ 7 h, n=75), early group(> 7-24 h, n=109), and delayed group (> 24 h, n=39). According to different surgical approaches, patients were also divided into 2 groups including the craniotomy group in which 107 cases were treated with craniotomy with bone flap and minimally invasive group in which 116 patients underwent minimally invasive puncture and drainage. Evaluation with the activities of daily living (ADL) grade was conducted at 7 days and 3 month post surgery for all patients.

The modified ADL scores demonstrated that the excellent rate at 7 days post surgery in the ultra-early group was 89.3% and significantly higher than those in the early group (62.3%) and delayed group (56.4%) (both P<0.05). The excellent rate at three months post surgery in the ultra-early group (91.9%) was also higher than those in the early group (65.7%) and delayed group (59.0%) (both P<0.05). The 7-day follow-up results suggested that the excellent rate in the craniotomy group (66.4%) was lower than the minimally invasive group (74.1%) (P<0.05), while the study at 3 months post operation did not reveal significant difference in excellent rate between the craniotomy (68.9%) and minimally invasive (77.4%) groups (P>0.05).

The prognosis of patients with hypertensive hemorrhage in the basal ganglia undergoing ultra-early surgical management seems to be better than those undergoing early or delayed operations. The treatment of craniotomy could lead to better perioperative periool outcomes and similar short-term results compared with the minimally invasive procedure for hematoma removal.

Cavernous vascular malformation is a common benign lesion, which most often occurs in the brain parenchyma. Among them, extraparenchymal cavernous hemangiomas (CHs) tend to occur in the cavernous sinus and middle cranial fossa, and are rarer in clinic, accounting for 0.4% ~2.0% of all intracranial vascular malformations. Some can also be seen in tentorium, carina, anterior cranial fossa, cerebellopontine foot, Meckel cavity, sella turcica and internal auditory tract, but are extremely rare, accounting for only 0.2% ~0.5% of intracranial vascular malformations^[1]。 cavernous sinus heman-giomas (CSHs) is a type of CHs, which is easily misdiagnosed as meningioma. Different from intracerebral CA, the clinical manifestations of CHs are similar to those of true hemangioma, and the related clinical symptoms will also be aggravated with the increasing size of hemangioma^[2]。 A total of 6 cases of CSHs were treated by the Head Gamma Knife Center of the Affiliated Hospital of Inner Mongolia Medical University from August 2010 to March 2015, and all of them achieved good results. The retrospective report is as follows.

Hypertensive cerebral hemorrhage is a common disease, and the most common site is putamen. Surgery is the most effective treatment for this disease, but the severe disability rate after operation is extremely high. Minimally invasive technique of directional catheterization is a gradually mature surgical method in recent years, which can not only reduce surgical trauma, but also achieve the purpose of clearing hematoma^[1]。 Magnetic Resonance diffusion tensor Fiber Bundle imaging is a further development of diffusion tensor imaging (DTI), which can determine the damage of moving fibers early^[2]。 Whether soft channel minimally invasive technique can minimize surgical injury and protect the motor fibers of patients is still under discussion. This article retrospectively enrolled 39 patients with hypertensive putamen hemorrhage who completed soft channel minimally invasive surgery and DTI examination from September 2011 to January 2015 in the Department of Neurosurgery, Huzhou Central Hospital, Zhejiang Province. Among them, 32 patients were followed up for 6 months after surgery. The efficacy was compared with 27 patients with hypertensive putamen hemorrhage who underwent craniotomy, DTI examination and 6-month follow-up at the same time.

multiple intracranial aneurysms (MIA) refer to the presence of two or more aneurysms in the cranium at the same time. MIA accounts for 15% to 35% of intracranial aneurysms^[1]。 Because surgical treatment of MIA faces risks such as large exposure range, deep surgical field and more prone to complications, there has been controversy in the treatment strategy. Clipping MIA by one-side approach can reduce the risk and economic pressure brought by secondary surgery on the one hand, but on the other hand, it also increases the risk of primary surgery. Nine cases of bilateral MIA were treated with unilateral craniotomy from June 2013 to February 2016 in the Department of Neurosurgery of North Jiangsu People's Hospital, and good clinical results were obtained. The retrospective analysis is as follows.

With the progress of material science, the interventional treatment of intracranial aneurysms is becoming more and more perfect, especially in the position where craniotomy is difficult to expose its advantages are very obvious, and good microcatheter shaping is one of the key steps in endovascular treatment^[1,2,3]。 There are two technical difficulties in aneurysm embolization: one is that the microcatheter is accurately placed in the aneurysm sac; Another is that during embolization, the tip of the microcatheter needs to maintain good stability to prevent the microcatheter from prolapsing, thus reducing embolization complications^[4]。 The precise shaping of the microcatheter directly determines the success of the operation. The Department of Neurosurgery, Affiliated Hospital of Binzhou Medical College, used 3D printing technology to reconstruct the aneurysm complex in three dimensions, analyzed the angle and spatial position of the aneurysm and the tumor-bearing artery, simulated the movement of the microcatheter in the blood vessel, and designed a microcatheter shape model that fits the anatomy of the patient's own aneurysm, which was used to guide the shaping of the microcatheter, thus improving the success rate of operation. Thirteen operations performed in the previous period are summarized.

To explore the influencing factors of early disappearance of abnormal muscle response (AMR) during microvascular decompression for hemifacial spasm(HFS) and the clinical outcomes.

During the period from January to December of 2014, a total of 372 patients of HFS underwent microvascular decompression (MVD) at Neurosurgery Department of Nanjing Drum Tower Hospital. Characteristic AMR of HFS was observed in 359 patients intraoperatively, among whom 33 patients showed early permanent disappearance of AMR before decompression and the remaining 326 patients did not. Clinical features and outcomes of 359 cases were analyzed retrospectively.

Offending vessels were identified in all 359 cases. In the 33 patients with early disappearance of AMR, no indentation was observed on their facial nerves, and immediate and delayed (7 days post operation) resolution of symptoms occurred in 32 cases and 1 case, respectively. No complications were reported during the follow-up period in the 33 patients. In the 326 patients without early disappearance of AMR, 39 (12%) cases demonstrated indentation on the facial nerve.In this group, AMR disappeared completely in 305(93.6%) patients after decompression. Although sufficient decompression was achieved, AMR did not disappear in the other 21 (6.4%) patients. Out of the 326 patients, immediate and delayed (2-310 days post operation) symptom resolution occurred in 267 and 57 cases, respectively, and HFS was not relieved in the remaining 2 cases. Hearing loss and delayed facial paralysis were observed in 4 and 9 cases, respectively.The two groups of patients were followed-up for 20-32 months, and no recurrence was observed. The surgical outcomes in patients with early AMR disappearance were significantly better than the other group(P=0.027). The two groups did not differ for postoperative complications. There were no statistically significant differences in gender, age, duration of illness, the side of HFS or the type of offending vessels between the two groups(P>0.05).

Less stress of offending vessels might be responsible for early disappearance of AMR. Compared with those without early AMR disappearance, the patients whose AMR disappear before decompression seem to have better outcomes.

To evaluate the clinical value of collateral venous circulation assessment in operations of parasagittal meningiomas (PSM).

A total of 71 patients with PSM were enrolled in this study who underwent surgical operations at Department of Neurosurgery, Fuzhou General Hospital from October 2011 to December 2015. The examination of MRV was conducted prior to operation to reveal the location of tumors and degrees of their invasion of the venous sinus. The collateral venous circulation was graded from 0 to 4 based on the Qureshi Collateral Circulation Assessment with certain modifications, guided by which operations were conducted and the patients' outcomes were retrospectively analyzed.

Among the 71 patients, tumors were located in the anterior (n=12), middle (n=46) and posterior (n=13) regions of superior sagittal sinus. Collateral venous circulation was not observed (grade 0) in 26 (36.6%) cases; 8 (11.3%) patients were graded class 1; 12 (16.9%) and 25 (35.2%) patients belonged to grade 3 and 4, respectively. Simpson grade Ⅰ/Ⅱ and Ⅲ resections were achieved in 67 (94.4%) and 4 (5.6%) cases, respectively. The superior sagittal sinus was excised in 15(21.1%) cases, reconstructed in 8 (11.3%) cases and electrocoagulated in 48 (67.6%) cases. The median length of postoperative follow-up was 34 months (range 3-70 months). Fourteen (19.7%) patients reported post-operative new neurological dysfunctions or deterioration of original symptoms, and permanent neurological dysfunctions occurred in 8 (11.3%) cases. The percentages of poor outcomes in patients with grade 0-4 collateral venous circulation were 2/26, 1/8, 1/12 and 4/25, respectively, and their differences were not statistically significant (P=0.830). Postoperative venous sinus thrombosis occurred in 3 (4.2%) patients, among whom one (1.4%) was cured, one (1.4%) died and one (1.4%) reported recurrence 1 year post surgery.

Extracranial collateral venous circulation plays an important role in the design of incision. Preoperative assessment of collateral venous circulations for PSM patients help guide the venous treatment and improve their outcomes.

To investigate the neuroradiological features of MRI and CT of intracranial hemangioendothelioma (HE) and their relationship to histopathological characteristics.

We conducted a retrospective analysis of 7 patients with pathologically confirmed intracranial HE who were admitted to Department of Neurosurgery, Taizhou People's Hospital from January 2008 to June 2016. Their imaging features and pathological results were studied.All patients were performed MRI examinations.Among them 3 patients underwent CT scan and 1 patient underwent MRA examination.

Among the 7 patients, 2 had lesions on the right side of the skull (1 on the frontal bone and 1 on the parietal bone), 2 in the tentorium, and 1 in the cerebral falx, 1 in the right cavernous sinus, and 1 in the right temporal lobe. The diameters of the lesions measured 2.1-5.3 cm with an average of (4.1±1.1) cm. Most appeared iso- or hypointense on T1-weighted MRI, with a multiple fleck pattern or small punctate hyper-intensities. Lesions appeared as inhomogeneous hyperintense regions on T2-weighted MRI, with multiple enlarged and tortuous blood flow voids. After contrast-enhanced scanning, lesions in all 7 cases had delayed enhancements, which showed a honeycomb-like marked enhancement. One case underwent MRA examination and the result showed abnormal increase of vascular imaging around the tumor. The CT scans showed a high-density region with many small round higher-density foci. Of the 7 cases, 4 were epithelial HE, 2 were retiform HE, and 1 was Kaposiform HE. Histological examination revealed endothelial cell proliferation, with vascular lesions and mucous matrix or dense fibrous mesenchyme.

MRI and CT Imaging findings of intracranial HE include certain characteristics, which might be closely related to its pathologic basis.

To explore the assessment value of plasma copeptin level in postoperative diabetes insipidus of pituitary adenoma patients.

A total of 53 patients with pituitary adenoma were admitted to Department of Neurosurgery, Fuzhou General Hospital from March 2014 to March 2015 and their data were consecutively collected and prospectively analyzed in this study. All cases underwent tumor resection using transsphenoidal approach. MRI examination was performed preoperatively to observe posterior pituitary bright spot (PPBS). The plasma copeptin level was detected with the method of ELISA preoperatively and 1 day post surgery. The volumes of urine were documented postoperatively. Patients were divided into diabetes insipidus group (n=23) and control group (without diabetes insipidus, n=30). In addition, patients were also separated into PPBS positive group (n=45) and PPBS negative group (n=8). The relationship between copeptin, PPBS and postoperative diabetes insipidus was analyzed.

In the diabetes insipidus group, the average concentration of copeptin was 5.35(4.24, 8.25)pmol/L preoperatively, which was not significant different from that assessed 1 day post surgery 4.87(4.08, 6.43)pmol/L (P>0.05). In the control group, the preoperative and postoperative (1 day post surgery) concentrations of copeptin were 6.82(4.99, 10.77)pmol/L and 6.21(4.81, 9.84)pmol/L, respectively, and the difference was not significant (P>0.05). The average concentrations of copeptin in the diabetes insipidus group were significantly lower than those in the control group (P<0.05) both preoperatively and postoperatively. The average concentration of copeptin 6.57(4.87, 10.39)pmol/L in PPBS-positive group was higher than that in PPBS-negative group 4.65(3.49, 6.23)pmol/L (P<0.05). There was no correlation between the intensity of PPBS and plasma copeptin level (P>0.05).

Copeptin could serve as a predictive tool for postoperative diabetes insipidus in pituitary adenoma patients. Preoperative and postoperative (1 day post surgery) low plasma copeptin levels might suggest a higher risk of postoperative diabetes insipidus.

To investigate the mechanism of miRNA-451 overexpression in the regulation of epithelial-mesenchymal transition(EMT) in human glioma cells through target calcium binding protein 39 (CAB39) and to explore the effects of miRNA-451 overexpression on invasion and migration of glioma cells.

The U251 glioma cells were cultured and divided into 3 groups including control group, nonsense sequence group and miRNA-451 mimics treatment group (briefly miRNA-451 group). The expression of miRNA-451 was detected by RT-PCR in glioma cells after transfection. The expression proteins of CAB39, E-cadherin, N-cadherin, Vimentin, TWIST, MMP-2, MMP-9, Snail, AKT, P-AKT were detected by Western blot. Cell immunofluorescence assay was used to further validate the expression levels of N-cadherin and Vimentin. The wound healing and transwell experiments were performed to detect changes in cell invasion and migration abilities.

The miRNA-451 expression level in the miRNA-451 group was significantly higher compared with those in the control and nonsense sequence groups (both P<0.05). The results of Western blot revealed that the expression levels of CAB39, N-cadherin, Vimentin, TWIST, MMP-2, MMP-9, Snail, P-AKT in miRNA-451 group were decreased (allP<0.05) and the expression level of E-cadherin was increased as compared with those in the control and nonsense sequence groups (allP<0.05). Cell immunofluorescence assay showed that the relative expressions of N-cadherin and Vimentin in miRNA-451 group were significantly lower than those in control group (bothP<0.05). The results of the wound healing showed that the scar repair rate of miRNA-451 group was significantly lower than those in the control and nonsense groups at 24 hrs or 48 hrs post would healing(allP<0.05). The number of cells in the miRNA-451 group was significantly decreased as compared with the other two groups at 48 hrs post transfection (bothP<0.05).

The regulation of PI3K/AKT pathway by miRNA-451 might be through the decrease of CAB39 expression, which could cause the inhibition of EMT in human glioma cells and their invasion and migration.

To establish the cell injury model with the mechanical loading system in HT-22 cell lines.

HT-22 cell lines were seeded with Bioflex cell plate, and applied with tensile stress-induced cell injury at the degree of deformation of 13.4% and frequency of 1 Hz by FX-5000TFL mechanical loading system. HT-22 cells were divided into control, 6 h, 12 h, and 24 h group, respectively. The mean cell area and thickness were assessed by real-time digital holographic microscopy (DHM), and Trypan blue assay and lactate dehydrogenase (LDH) detected kit were then performed to determine the cell viability and the level of LDH, respectively. Finally, the change of cell cycle and Sub-G₁ peak were measured by the flow cytometry (FCM).

(1) Compared with the control, HT-22 cells showed a reduction in area (from 603.9±28.5 μm ² to 182.9±4.5 μm ^2,t=21.93, P<0.01) and an increase in thickness (from 4.0±0.2 μm to 8.3±0.3 μm,t=16.65, P<0.01) assessed using the digital holographic microscopy. (2) Cell viability test showed that the cell survival rate of 6 h group (59.7±4.5%) was significantly reduced than that of control group(95.0±1.6%) (t=10.44, P<0.01). Although the cell survival rates of 12 h and 24 h groups were higher than that of 6 h group (t=4.56, P<0.05;t=6.45, P<0.01, respectively), there was also significant difference in cell survival rate between 12 h, 24 h, and control groups (t=7.56, P<0.01;t=3.873, P<0.05, respectively). (3) LDH assay showed that the level of LDH in 6 h group (273.9±4.6 ng/L) was significantly increased than that of control (51.7±5.8 ng/L,t=42.48, P<0.01), while those in 12 h (255.2±4.4 ng/L) and 24 h groups (240.2±6.0 ng/L) were lower than that in 6 h (separately,t=4.14, P<0.05;t=6.28, P<0.01). (4) As demonstrated in flow cytometry (FCM) assay, tensile stress-induced cell injury caused an appreciable accumulation in Sub-G₁ phase (6.5±0.6%) compared to that of the control group (0.6±0.3%, t=14.90, P<0.01). However, the Sub-G₁ population was decreased with the extension of time, particularly the lowest in the 24 h group (2.1±0.5%) compared to that of the 6 h group (t=9.61, P<0.01).

In vitro models of traumatic brain injury could be successfully established with the mechanical loading system, and the novel cell injury model in HT-22 cells might serve as a novel useful, effective and controllable approach in developing models of traumatic brain injury.

To investigate the effect of Purα on the hippocampal neuronal apoptosis and learning and memory in the rat epilepsy model induced by lithium-pilocarpine.

A total of 90 Sprague Dawley rats of 6-8 weeks were randomly divided into Purα overexpression group, control group and Purα silence group with 30 rats in each group. Rats in the overexpression and silence groups were administered overexpressed and silenced Purα lentivirus (5×10⁸ TU/ml), while the controls were administered the same volume of saline. Two weeks later, rats in all 3 groups were intraperitoneally injected with lithium chloride (127 mg/kg) and, after 18-20 h, were administered pilocarpine (30 mg/kg) for establishment of epilepsy model. The assay of Western blot was used to measure the expression of Purα and Caspase-3, and Caspase-3 was detected by immunohistochemistry technique. The Morris water maze was employed to assess the rats' function of learning and memory.

The Western blot assay revealed that the relative expression levels of Purα in overexpression, control and silence groups were 0.32±0.04, 0.39±0.01 and 0.17±0.02, respectively; those of Caspase-3 were 0.95±0.29, 0.46±0.05 and 1.35±0.10. The Caspase-3 positive cells in the CA3 region of hippocampus were 7.01±2.05, 9.01±2.21 and 13.8±1.93 for overexpression, control and silence groups, respectively; those in the dentate gyrus were 9.41±0.84, 12.50±2.46 and 17.60±2.51. The latencies to seizure in the 3 groups were 10.10±1.19 min, 9.30±1.70 min and 5.10±1.59 min; the seizure durations were 3.07±1.09 h, 5.57±2.11 h and 8.11±1.26 h. The differences in the parameters above between the 3 groups were all determined to be statistically significant (P<0.01). Assessed with the Morris water maze, the rats' stay time in the platform quadrant was 20.24±4.13 s, 15.67±3.58 s and 10.03±1.72 s; the crossing times were 8.38±2.62, 7.25±3.49 and 6.38±2.07 for the overexpression, control and silence groups, respectively; and the differences were significant compared with control (P<0.05). The escape latency was always the longest in overexpression group and shortest in silence group regardless time points post model establishment, and the differences were statistically significant (P<0.05).

Purα could reduce hippocampal apoptosis caused by seizures and therefore protect the hippocampal neurons in the rats with epilepsy.

Non-hemorrhagic subdural effusion is a rare complication after intracranial electrode placement, and its postoperative CT findings are low-density shadows, so it is often overlooked. However, this complication can progress rapidly and even lead to serious complications such as cerebral hernia, which requires early diagnosis and treatment. The Department of Neurosurgery of Beijing Tiantan Hospital affiliated to Capital Medical University treated a patient with non-hemorrhagic subdural effusion in March 2014. Now, combined with relevant literature, the clinical characteristics, diagnostic methods and treatment principles of the disease are summarized, aiming at deepening clinicians' understanding of non-hemorrhagic subdural effusion, so as to diagnose such complications early and improve the prognosis of patients.

Vertebral artery pseudoaneurysm refers to the destruction of the full-thickness structure of the vertebral artery wall, and the blood spills out of the vascular lumen and is wrapped by the surrounding tissue to form an aneurysm. The aneurysm wall has no three-layer structure of the complete artery wall, and is the periarterial tissue or only the residual aortic adventitia^[1]。 In May 2016, a case of right vertebral artery pseudoaneurysm was treated in the Department of Vascular Surgery, Changhai Hospital, Second Military Medical University. The symptoms of right vertebral artery blood stealing and brachial plexus compression were obvious. The hybrid surgical method of right vertebral artery retrograde embolization combined with pseudoarteriectomy + brachial plexus release was used. After the treatment was completed in the first stage, the patient's postoperative symptoms could be relieved and he recovered well. The report is now as follows.

Traumatic internal carotid artery pseudoaneurysm (PSA) is a rare disease. According to foreign reports, the incidence rate of head and neck trauma is about 9%^[1], accounting for about 1% of all intracranial aneurysms^[2]。 There are few reports at home and abroad on local cerebral infarction caused by thrombus shedding in combined tumors.

epidermoid cyst (EC) accounts for no more than 2% of intracranial lesions^[1,2,3,4]It is common in cerebellopontine angle (CPA) area, parasellar, lateral fissure, ventricle and other extracerebral areas, and a few can also occur in the brain or cerebellar parenchyma. EC originating from the brainstem is rare^[1,2,3,4,5]。 There are literature reports abroad that the malignant transformation into squamous cell carcinoma on the basis of cyst^[6]。 However, malignant transformation of brainstem EC has rarely been reported so far. In March 2015, a patient with malignant EC in the brainstem was admitted to the Department of Neurosurgery of Wuxi Second Hospital affiliated to Nanjing Medical University, which is reported in the literature as follows.

optic pathway glioma (OPG) is a low-grade astrocytoma originating from the optic nerve, optic chiasm, optic tract or hypothalamus, which seriously affects the visual acuity and endocrine function of patients^[1]。 Prevalent in children (<18 years old), about 10% of patients were ≥19 years old, and 60% to 75% were female. There is no significant correlation between the prevalent site and age, but it may affect the prognosis. The total mortality rate involving optic nerve is about 5%, while the mortality rate involving hypothalamus is about 50%, and the quality of life of patients is poor^[2]。 Due to the variation of clinical course of OPG and the younger age of patients, the choice of treatment mode is difficult^[3]。 Tremendous progress has been made in the diagnosis and treatment of OPG in the past 10 years, so this article reviews the clinical features and treatment strategies of OPG.

Intracranial aneurysm has the characteristics of high incidence, low rupture rate and high residual mortality after rupture and hemorrhage^[1,2]。 Therefore, the individualized assessment of the rupture risk of intracranial aneurysms has become the most important subject in aneurysm research. Traditional methods of intracranial aneurysm examination, such as digital subtraction angiography (DSA), CT angiography (CTA), magnetic resonance angiography (MRA), etc., are based on the blood flow in the vascular lumen for imaging, and indirectly speculate the risk of aneurysm rupture through information such as the location, size and shape of the aneurysm. This evaluation method is the most widely used clinically, but its accuracy is poor. Histopathological study of intracranial aneurysms showed that there were interruption of endothelial necrosis, necrosis and proliferation of smooth muscle cells and collagen fiber proliferation in the tumor wall^[3,4,5]。 Therefore, a rupture risk assessment method based on aneurysm wall features will be more meaningful.

3D printing technology is a new application technology that combines digital 3D imaging with modern high-tech continuous printing. This new technology has been applied to human production, life and some industrial fields. 3D printing technology plasticizes the characteristics of simulated entities through layered processing, superposition molding and layer-by-layer addition, making it unique in high-precision, high-difficulty and highly complex individualization process. At present, the development of medicine gradually tends to precision treatment, and 3D printing technology is much better than traditional industries, especially in implant manufacturing, in vitro simulation, tissue repair and organ transplantation, showing unique advantages. With the success of 3D printing of organs, cells and bones, 3D printing technology will become an artifact in the medical field^[1,2,3]。 This article reviews the current application and progress of 3D printing in neurosurgery.

Schwannoma is the most common benign tumor in the spinal canal, which is generally single, and multiple ones are rarer. Multiple schwannoma often brings difficulties in clinical diagnosis and treatment because it involves a wide range of nerve and spinal cord segments. Early diagnosis, total resection as much as possible, and maximum protection of nerve function are important factors to improve the curative effect. This article reviews the etiology, clinical features, imaging features, treatment and prognosis of multiple schwannomas in the spinal canal.

Although the mortality rate of aneurysmal subarachnoid hemorrhage (aSAH) has decreased with the advancement of diagnosis and treatment technology, it remains the main factor of stroke-related death^[1]。 At present, the recognized risk factors related to aSAH mortality include poor clinical grade (Hunt-Hess, SAH grade of the World Federation of Neurosurgeons, Fisher score, etc.), elderly patients, aneurysm rebleeding, aneurysm diameter greater than 10 mm and cerebral infarction caused by cerebral vasospasm, among which the direct effect of primary hemorrhage, aneurysm rupture and rebleeding, and cerebral vasospasm are the main factors leading to death after aSAH^[1]。 However, recent studies have found that global cerebral edema (GCE) is another important factor leading to poor prognosis of SAH. This article reviews the research progress of hemispheric swelling after aSAH.

Professor Zuo Huancong, a famous neurosurgeon in China and a famous teacher of a generation, died in Beijing on February 15, 2017 at the age of 72.