Safety of Apixaban Monotherapy for Non-Valvular Atrial Fibrillation-Related Acute Stroke with Intra-/Extracranial Artery Stenosis.

INTRODUCTION: We investigated whether apixaban is safe for the prevention of further adverse events in non-valvular atrial fibrillation (NVAF) patients with intra-/extracranial artery stenosis (Stenosis group) compared with acute large vessel occlusion without intra-/extracranial artery stenosis (No stenosis group). We also examined whether combination therapy using apixaban and antiplatelet is safe. METHODS: ALVO (Apixaban on clinical outcome of patients with Large Vessel Occlusion [LVO] or stenosis) was a historical and prospective multicenter registry at 38 centers in Japan. Patients with NVAF and acute LVO or stenosis who received apixaban within 14 days after onset were included. We conducted the post hoc analysis using the ALVO dataset. We compared patients with stenosis versus those without stenosis in terms of the primary outcome, which was defined as a composite of all-cause death, major bleeding events, and ischemic events 365 days after onset. RESULTS: Of the 662 patients, 54 (8.2%) patients were classified into the Stenosis group, and 104 patients of the total (16%) reached the primary outcome. The cumulative incidence of primary outcome was not significantly different between the No stenosis and the Stenosis groups (hazard ratio [HR] 1.2, 95% confidence interval [CI]: 0.64-2.4; p = 0.52). Even after adjustment for predictive clinical variates, no significant difference in the primary endpoint between the No stenosis and the Stenosis groups was shown (adjusted HR 1.2, 95% CI: 0.59-2.5; p = 0.60). Fifty patients (7.6%) used an antiplatelet with apixaban. Among the Stenosis group patients, the cumulative incidence of the primary outcome was significantly higher among patients treated with an antiplatelet and apixaban (HR 3.5, 95% CI: 1.0-12; p = 0.048). CONCLUSION: Apixaban monotherapy appears safe for the prevention of further adverse events in the Stenosis group patients similar to the No stenosis group patients. Concomitant use of an antiplatelet might not be favorable in patients with stenosis.

Endovascular vs Medical Management for Late Anterior Large Vessel Occlusion With Prestroke Disability: Analysis of CLEAR and RESCUE-Japan.

BACKGROUND AND OBJECTIVES: Current guidelines do not address recommendations for mechanical thrombectomy (MT) in the extended time window (>6 hours after time last seen well [TLSW]) for large vessel occlusion (LVO) patients with preexisting modified Rankin Scale (mRS) > 1. In this study, we evaluated the outcomes of MT vs medical management in patients with prestroke disability presenting in the 6- to 24-hour time window with acute LVO. METHODS: We analyzed a multinational cohort (61 sites, 6 countries from 2014 to 2020) of patients with prestroke (or baseline) mRS 2 to 4 and anterior circulation LVO treated 6-24 hours from TLSW. Patients treated in the extended time window with MT vs medical management were compared using multivariable logistic regression and inverse probability of treatment weighting (IPTW). The primary outcome was the return of Rankin (ROR, return to prestroke mRS by 90 days). RESULTS: Of 554 included patients (448 who underwent MT), the median age was 82 years (interquartile range [IQR] 72-87) and the National Institutes of Health Stroke Scale (NIHSS) was 18 (IQR 13-22). In both MV logistic regression and IPTW analysis, MT was associated with higher odds of ROR (adjusted OR [aOR] 3.96, 95% CI 1.78-8.79 and OR 3.10, 95% CI 1.20-7.98, respectively). Among other factors, premorbid mRS 4 was associated with higher odds of ROR (aOR, 3.68, 95% CI 1.97-6.87), while increasing NIHSS (aOR 0.90, 95% CI 0.86-0.94) and decreasing Alberta Stroke Program Early Computed Tomography Scale score (aOR per point 0.86, 95% CI 0.75-0.99) were associated with lower odds of ROR. Age, intravenous thrombolysis, and occlusion location were not associated with ROR. DISCUSSION: In patients with preexisting disability presenting in the 6- to 24-hour time window, MT is associated with a higher probability of returning to baseline function compared with medical management. CLASSIFICATION OF EVIDENCE: This investigation's results provide Class III evidence that in patients with preexisting disability presenting 6-24 hours from the TLSW and acute anterior LVO stroke, there may be a benefit of MT over medical management in returning to baseline function.

Cerebrospinal Fluid CSF Flow Artifacts are Associated with Brain Pulsation in Patients with Severe Carotid Artery Stenoses.

OBJECTIVE: We investigated the factors associated with cerebrospinal fluid (CSF) flow artifacts on fluid-attenuated inversion recovery imaging in patients with carotid artery (CA) stenosis. METHODS: Each CSF artifact grade was defined by comparing the highest intensity in a given region of interest (ROI) to those in reference ROIs, as follows: higher than the intensity of normal white matter in the centrum semiovale = 2 points; equal to or less than the white matter, and higher than CSF = 1 point; and equal to CSF = 0. CSF flow scores in eight sites were measured and added to the total score (0 -16). The prevalences of each finding, specifically white matter lesions, CA stenoses and brain atrophy, were compared using multivariate logistic regression models. RESULTS: We evaluated the findings in 54 patients with CA stenosis treated by CA stenting (CAS) and 200 adults with no history of neurological disorders (control group). Adjusted by stroke risk factors, a CSF flow score ≤ 11 was positively associated with CA stenosis, heart rate > 70 / min, and brain atrophy, and negatively with the female gender. The score was 12.8 ± 1.8 in the control group and 12.0 ± 2.0 in CA stenosis group after CAS, which was significantly higher than before CAS (10.4 ± 2.8, p<0.001). CONCLUSION: The CSF flow score was associated with female gender, brain atrophy, heart rate, and severe CA stenosis, and was found to be elevated after revascularization.

Asymptomatic cerebral findings on 3-Tesla MRI in patients with severe carotid artery stenoses.

BACKGROUND AND PURPOSE: Small vessel diseases (SVDs) are often asymptomatic. However, SVDs significantly influence the prognosis in patients with large vessel diseases (LVDs). We investigated asymptomatic cerebral findings on 3-Tesla MRI in patients with severe carotid artery (CA) stenoses, compared to peoples without a past history of neurological disorders, including strokes. METHODS: We retrospectively analyzed the prevalences of various asymptomatic cerebral findings which were intracerebral hemorrhages (ICHs), cortical superficial siderosis, ventricular dilatation (Evans' index) and SVDs including cerebral microbleeds (CMBs), lacunar infarctions (LIs), deep white matter hyperintensities (WMHs), periventricular hyperintensities (PVHs). The prevalence of each finding was compared using multivariate logistic regression models with adjustment for stroke risk factors. RESULTS: We evaluated the findings in 54 patients with severe CA stenosis treated by stenting (CA stenosis group) and 200 adults with health screening tests of the brain and no past history of neurological disorders (control group). Multivariate analyses adjusted for age ≥ 65 years old, female gender, hypertension, hyperlipidemia, diabetes mellitus, alcohol consumption, and smoking index revealed that the prevalences of severe PVHs, severe deep WMHs, asymptomatic deep ICHs, and asymptomatic LIs were significantly higher in the CA stenosis group than the control group. However, there were no significant differences in the prevalences of CMBs, or the remaining asymptomatic findings described above. CONCLUSIONS: With pathological differences between SVD and LVD, asymptomatic SVDs except CMBs and deep ICHs often co-exists severe CA stenosis as a presentative LVD.

Reperfusion Therapy Brings Apixaban Administration Forward in Patients with Nonvalvular Arterial Fibrillation with Anterior Circulation Large Vessel Occlusion or Stenosis.

OBJECTIVE: The initiation of anticoagulant administration after large vessel occlusion (LVO) or stenosis with nonvalvular arterial fibrillation (NAVF) is controversial. We evaluate the timing of anticoagulation and its relationship with clinical factors. METHODS: We enrolled 595 anterior circulation LVO or stenosis with NAVF cases from 38 stroke centers. Laboratory data; activities of daily living; the Alberta Stroke Program Early CT Score (ASPECTS); the National Institutes of Health Stroke Scale (NIHSS) score; occluded artery; treatment methods; date of the initiation of apixaban administration and outcome were recorded. Multivariate analyses were performed after univariate analysis. RESULTS: The median start of apixaban administration after the stroke was 2 days (interquartile range, 1-5; range, 0-14). Multivariate analysis of variance showed that non-internal carotid artery occlusion (F value 4.60), reperfusion therapy (31.1), high ASPECTS (6.27) before anticoagulant intake, and absence of intracranial hemorrhage (12.9) were significantly correlated with early apixaban administration. Multiple logistic regression analysis for independent living at 90 days after the stroke showed significant factors: aging (odds, 0.94; 95% confidence interval [CI], 0.91-0.97); male (odds, 0.46; 95% CI, 0.26-0.79); prestroke independence (odds, 20.7; 95% CI, 6.48-93.9); number of white blood cells (odds, 0.99; 95% CI, 0.97-1.00); non-internal carotid artery occlusion; NIHSS score at 72 hours after the stroke (odds 0.92; 95% CI, 0.89-0.96); ASPECTS before apixaban intake (odds, 1.15; 95% CI, 1.00-1.31) and initiation of apixaban (odds, 0.91; 95% CI, 0.83-0.99). CONCLUSIONS: Early administration of apixaban is induced by nonsevere infarction, reperfusion therapy or none of intracranial hemorrhage and it correlates with an independent long-term outcome.

Elongated Internal Carotid Arteries in Patients with Severe Carotid Artery Stenosis.

OBJECTIVE: This study aimed to investigate the risk factors and asymptomatic cerebrovascular diseases associated with elongated internal carotid arteries (ICAs) and the relationship between ICA elongation and severe carotid artery (CA) stenosis. METHODS: We evaluated risk factors for stroke and magnetic resonance imaging (MRI) findings in patients with severe CA stenosis compared with people without neurological disorders who underwent brain screening (controls). On magnetic resonance angiography (MRA) images, we measured the longest distance, defined as the ICA distance, from the most distant anterior wall of the cervical ICA at the site of bending or kinking to the line between the origin of the external CA and the anterior protrusion of the ICA near the petrosal bone. We retrospectively compared various asymptomatic findings, including cerebral microbleeds, lacunar infarctions, and deep white matter hyperintensities (WMHs), between participants with an ICA distance ≥ 1.2 cm vs. < 1.2 cm. The prevalence of findings and stroke risk factors were compared using multivariate logistic regression models. RESULTS: We evaluated 53 patients (70.0 ± 8.1 years old, nine female) with severe CA stenosis treated by CA stenting and 400 controls (63.0 ± 9.2 years old, 227 females). Multivariate analyses showed that ICA distance ≥ 1.2 cm was associated with age ≥ 65 years (odds ratio (OR) = 1.8, p < 0.01), severe deep WMHs (OR = 2.0, p = 0.02), and severe CA stenosis (OR = 0.17, p < 0.01). CONCLUSION: ICA elongation, measured by ICA distance, was positively associated with age and deep WMHs and negatively associated with severe CA stenosis.

Virtual test occlusion for assessing ischemic tolerance using computational fluid dynamics.

BACKGROUND: Ischemic tolerance has been evaluated by the balloon test occlusion (BTO) for cerebral aneurysms and tumors that might require parent artery occlusion during surgery. However, because of its invasiveness, a non-invasive evaluation method is needed. In this study, we assessed the possibility of virtual test occlusion using computational fluid dynamics (CFD) as a non-invasive alternative to BTO for evaluating ischemic tolerance. METHODS: Twenty-one patients who underwent BTO were included in the study. Virtual test occlusion was performed using CFD analysis, and the flow rate (FR) and wall shear stress (WSS) of the middle cerebral artery on the occlusion side were calculated. The correlations between these parameters and examination data including the parameters of computed tomography perfusion during BTO were assessed and the cutoff value of CFD parameters for detecting the good collateral group was calculated. RESULTS: The FR was strongly correlated with mean transit time (MTT) during BTO and moderately correlated with collateral flow grade based on angiographic appearance. The WSS was moderately correlated with collateral flow grade, mean stump pressure (MSP), and MTT. Furthermore, the FR and WSS were strongly correlated with the total FR and the diameters of the inlet vessels. The cutoff value of FR for detecting the good collateral group was 126.2 mL/min, while that of the WSS was 4.54 Pa. CONCLUSION: The parameters obtained through CFD analysis were correlated with collateral flow grade and MSP in addition to MTT. CFD analysis may be useful to evaluate ischemic tolerance as a non-invasive alternative to BTO.

Effect of prior antiplatelet therapy on large vessel occlusion in patients with non-valvular atrial fibrillation newly initiated on apixaban.

INTRODUCTION: We evaluated the effect of prior antiplatelet therapy on large vessel occlusion (LVO) in patients with non-valvular atrial fibrillation (NVAF) newly initiated on apixaban. METHODS: Patients with acute LVO with acute stroke due to NVAF or stenosis with NVAF started on apixaban within 14 days of onset were enrolled. We compared incidence of major bleeding, cerebral hemorrhage, ischemic events, cerebral infarction, and all-cause mortality between patients with and without prior antiplatelet therapy for acute LVO. We also compared these events between patients who continued antiplatelet therapy after onset (continued group) and those who discontinued it (discontinued group). Hazard ratios were estimated after adjusting for confounders; interaction was evaluated considering intravenous thrombolysis (IVT) or endovascular treatment (EVT) according to major bleeding. RESULTS: The study comprised 686 eligible patients (excluded [n = 194]; enrolled [n = 492]). The antiplatelet group consisted of older patients (mean: 79 vs. 76 years; p = 0.006) and had a higher cumulative incidence of major bleeding (7.3% vs. 2.9%, p = 0.003). The incidence of ischemic events and all-cause mortality was similar between the groups. Among the 109 patients in the antiplatelet group, the cumulative incidence of major bleeding, ischemic events, and all-cause mortality was comparable between continued group (n = 26) and discontinued group (n = 83). There were no significant differences between groups with and without IVT/EVT. However, major bleeding occured more frequently in the antiplatelet group without IVT. CONCLUSION: Prior antiplatelet therapy for LVO in patients with NVAF newly initiated on apixaban was associated with major bleeding, which was more frequent in the antiplatelet group without IVT.

Usefulness of Preoperative Simulation Using a Stereolithographic 3D Printer in Cerebral Aneurysm Coil Embolization.

Objective: We present a preoperative simulation of cerebral aneurysm coil embolization using a hollow model of cerebral blood vessels created by a stereolithography (SLA) 3D printer. Case Presentation: The patient was a 66-year-old woman. During follow-up, coil embolization was planned for an expanding paraclinoid aneurysm. A hollow cerebral vascular model was created preoperatively using an SLA 3D printer. The catheter was malleable and inserted into the hollow model, which enabled the surgeons to confirm its movement, stability, and ease of insertion. In the surgical procedure, the catheter was easily inserted into the aneurysm without reshaping. The procedure was completed without stability problems. Conclusion: The use of a hollow model of cerebral blood vessels was useful as a preoperative simulation and improved the safety of the procedure.

Safety of Early Administration of Apixaban on Clinical Outcomes in Patients with Acute Large Vessel Occlusion.

Early administration of direct oral anticoagulants in patients with acute large vessel occlusion (LVO) and nonvalvular atrial fibrillation (NVAF) is a concern, as endovascular therapy (EVT) became highly utilized. We conducted a historical and prospective multicenter registry at 38 centers in Japan from July 2016 to February 2018. Patients aged ≥ 20 years with NVAF and acute LVO or stenosis who received apixaban within 14 days from onset were included. We compared patients who received apixaban < 48 h (Early group) and ≥ 48 h (Late group) after onset in terms of the primary outcome (a composite of ischemic events, major bleeding events, and all-cause deaths). The secondary outcomes were each component of the primary outcome. Among the 686 patients, the median time from onset to administration was 2.5 days (range, 0-14; Early 263, Late 423). The Alberta Stroke Program Early CT Score (ASPECTS) and diffusion-weighted imaging (DWI)-ASPECTS) were significantly higher in the Early group than in the Late group. Recombinant tissue plasminogen activator (rt-PA) and EVT were more utilized in the Early group (rt-PA 46% vs. 35%, p = 0.003; EVT 62% vs. 46%, p < 0.0001). The cumulative incidence of primary outcome was similar between groups (ischemic events: Early 1.9% vs. Late 0.5% at 30 days; 3.5% vs. 0.7% at 90 days, major bleeding 3.4% vs. 2.9% at 30 days; 5.0% vs. 3.4% at 90 days). Early administration of apixaban (< 48 h), after onset of acute LVO in patients with NVAF, was generally safe compared with those who received it Late (≥ 48 h). http://www.clinicaltrials.gov . Unique identifier: NCT02818868 (June 30, 2016).

[Development of Deep Venous Thrombosis Shortly after Neurological Surgery].

Little is known about the incidence and characteristics of deep venous thrombosis(DVT)developing shortly after neurological surgery. Lower extremity venous ultrasound scanning was performed before and after surgery, and retrospective data of 157 surgical cases, including endovascular surgery(42.0%), craniotomy(28.7%), burr hole(24.2%), and shunt(3.2%), were evaluated. DVT that had not been pre-operatively observed was discovered in five cases of surgery(five patients, 3.2%)on the day following the surgery, and it was asymptomatic in all cases. One patient was diagnosed with pulmonary thromboembolism as a complication. No difference in characteristic factors was observed between the presence and absence of DVT development. In addition, DVT was detected on preoperative examinations in 10 cases of surgery(10 patients, 6.4%). On the basis of these results, ambulation on the first postoperative day is considered mostly safe. On the other hand, taking into account the increase in the number of patients with DVT and the possibility that a thrombus present in calf veins propagates toward the proximal side, pre-and post-operative screening tests should be performed more often.

Cerebral aneurysm neck diameter is an independent predictor of progressive occlusion after stent-assisted coiling.

BACKGROUND: Some intracranial aneurysms treated by stent-assisted coiling (SAC) with incomplete occlusion undergo progressive occlusion (PO) during follow-up period. We analyzed the predictors for the occurrence of PO. METHODS: Among 74 cerebral aneurysms treated by SAC using the Enterprise or Neuroform stents from 2010 to 2015, we included 43 aneurysms with occlusion grade of neck remnant (NR, n = 36) or residual aneurysm (RA, n = 7) at the post-procedure. We defined PO as improvement in occlusion grade from RA to NR, or from NR or RA to complete occlusion on angiographic follow-up imaging at 6 months after the procedure. We analyzed the independent predictors for PO using a multivariate logistic regression model and receiver operating characteristic (ROC) curve analysis. RESULTS: Forty-three aneurysms were analyzed, with mean volume embolization ratio of 30.3 ± 6.7%. Twenty aneurysms (47%) achieved PO. Univariate analysis found that the median neck diameter of the aneurysms was smaller in aneurysms with PO than others. Multivariate logistic regression analysis also found that the odds ratio of neck diameter of the aneurysm for PO was 0.44 (95% CI, 0.19-0.82, p < 0.01). Moreover, ROC curve analysis for PO found that the optimal cut-off value of the neck diameter was 5.5 mm, with a sensitivity of 95%, specificity of 57% (p < 0.01). CONCLUSIONS: Incompletely occluded aneurysms with a neck diameter of 5.5 mm or less might be more likely to develop PO within 6 months after SAC by using Enterprise or Neuroform stents.

Double balloon protection during carotid artery stenting for vulnerable carotid stenosis reduces the incidence of new brain lesions.

BACKGROUND: The use of distal filter protection alone is associated with a high risk of ischemic complications when vulnerable carotid stenosis is treated by carotid artery stenting (CAS). Double balloon protection, a combination of distal balloon protection and proximal balloon occlusion, can be utilized. We assessed the outcome and complications of the double balloon protection method for vulnerable carotid stenosis. METHODS: Among 130 patients who underwent CAS from 2009 to 2014, we enrolled the following patients: those whose target lesion was vulnerable as evaluated by MRI, i.e., a signal ratio of plaque to posterior cervical muscle on T1-weighted images before CAS of ≥1.5, and those who underwent diffusion-weighted imaging (DWI) studies within 48 h after the procedure. Ninety patients were enrolled. We investigated DWI findings of the double balloon protection group compared with those of the simple distal balloon protection and distal filter protection groups. RESULTS: Sixty-four patients (71 %) underwent double balloon protection, 15 patients (17 %) simple distal balloon protection, and 11 patients (12 %) distal filter protection. Symptomatic embolic complications and new lesions on DWI after CAS were significantly less common in patients undergoing double balloon protection compared to distal balloon protection or distal filter protection (0 % vs. 20 %, 9 %, P < 0.01, and 30 % vs. 67 %, 82 %, P < 0.01, respectively). Logistic regression analysis also identified the odds ratio of double balloon protection for new lesions on DWI after CAS of 0.23 (95 % confidence interval: 0.07-0.70, P < 0.01) compared to simple distal protections. CONCLUSIONS: In the patients who underwent CAS for vulnerable carotid stenosis, double balloon protection was an independent significant factor associated with a reduction in the risk of new lesions on DWI after the procedure compared to conventional distal protections.

Design of Synthetic Polymer Nanoparticles That Facilitate Resolubilization and Refolding of Aggregated Positively Charged Lysozyme.

Designed polymer hydrogel nanoparticles (NPs) capable of facilitating resolubilization and refolding of an aggregated protein, positively charged lysozyme, are prepared. NPs designed to interact strongly with denatured lysozyme and relatively weakly with native lysozyme, facilitated resolubilization and refolding of aggregated lysozyme. Such NPs could be prepared by copolymerizing optimized combinations and populations of functional monomers. The refolded lysozyme showed native conformation and enzymatic activity. Eleven grams of aggregated protein was refolded by 1 g of NPs. However, NPs having low affinity to denatured lysozyme and NPs having high affinity to both denatured and native lysozyme showed relatively low facilitation activity. Our results suggest a potential strategy for the design of artificial chaperones with high facilitating activity.

[Fundamental study of the energy subtraction process using a monochromatic image for computed tomography angiography after coil embolization of a cerebral aneurysm].

Coil-embolized cerebral aneurysms are difficult to evaluate using computed tomography (CT) angiography (CTA) due to artifacts caused by the coil devices. This study was conducted to assess the practicality of energy subtraction processing using monochromatic images obtained using CTA after coil embolization of a cerebral aneurysm. In this study, the changes in the CT value of the contrast agent and the coil were analyzed not only at varying monochromatic energy levels but also by energy subtraction processing. Our analyses revealed an exponential change in the CT value of the contrast agent at any desired energy. We also found that the CT value of the coil was unchanged at the upper threshold of the grayscale limit. Based on these results, we were able to create images of changes in material-specific CT values and thus eliminate the material. Energy subtraction processing enabled us to distinguish between the contrast agent, the coil, and the artifacts from coil devices. We suggest that energy subtraction processing using monochromatic images can resolve the limitations of CTA after coil embolization of cerebral aneurysms.

[Strategy for the treatment of large-giant aneurysms in the cavernous portion of the internal carotid artery].

The treatment of a large-giant aneurysm in the cavernous portion of an internal carotid artery(ICA)requires occlusion of the ICA, with or without extracranial-intracranial(EC-IC)bypass surgery. Although a balloon occlusion test(BOT)is used to determine the need for bypass surgery and select the bypass type, the criteria are not well established. In this study, we retrospectively analyzed 10 consecutive patients(11 sides)with cavernous large and giant aneurysms treated during the past 8 years. Therapeutic strategies for each patient were selected according to the results of neurological and radiological examinations, and regional cerebral oxygen saturation. A total of 6 high-flow bypasses were placed before ICA occlusions. Three patients had STA-MCA bypasses before ICA occlusions, and two underwent endovascular ICA occlusion without bypass surgery. Favorable outcomes were obtained in all cases with respect to cranial nerve palsy, but one patient had insufficient ipsilateral cerebral blood flow postoperatively, and hemiparesis was revealed. An emergent STA-MCA bypass was performed in this case, which minimized the hemiparesis. Despite radiological evaluation during the BOT procedures, we had one false negative result. This indicates that the BOT requires increased sensitivity and specificity, and that a safety margin should be adopted when determining indications for bypass surgeries.

[Angiographic analysis of variations and anomalous origin of the anterior choroidal artery and posterior communicating artery].

OBJECT: The anterior choroidal artery (AchoA) is a very important artery for neurosurgeons and neuroendovascular surgeons. In fact the AchoA not only supplies the ventricles but also has important branches to the diencephalon, mesencephalon and cerebrum and also supplies motor and visual pathways. Review of the cerebrovascular embryology explains this variability in the anatomy of the developing AchoA and posterior communicating artery (PcomA)- posterior cerebral artery (PCA) distributions. CASE 1: A 47-year-old woman, with an unruptured left internal carotid artery (ICA) aneurysm. For the cerebral arterial aneurysm approximately 7 mm in size, we performed coil embolization with an assist balloon under general anaesthesia. CASE 2: A 63-year-old woman, with an unruptured right ICA aneurysm. Endeavouring to preserve the branch vessels, we undertook a craniotomy neck clipping operation. DISCUSSION AND CONCLUSION: It is thought that, usually, AchoA has its origin at the supraclinoid ICA distal to the PcomA. Our analysis of these two cases may be helpful for a better understanding of the vascular relations and anatomy of the AchoA and PcomA-PCA distributions. We emphasize the importance of recognizing such anomalies in planning surgical and interventional treatment.

Intravenous administration of mesenchymal stem cells derived from bone marrow after contusive spinal cord injury improves functional outcome.

Transplantation of mesenchymal stem cells (MSCs) derived from bone marrow has been shown to improve functional outcome in spinal cord injury (SCI). Systemic delivery of MSCs results in therapeutic benefits in a number of experimental central nervous system disorders. In the present study we intravenously administered rat MSCs derived from bone marrow at various time points after induction of a severe contusive SCI in rat to study their therapeutic effects. MSCs were systemically delivered at varied time points (6h to 28 days after SCI). The spinal cords were examined histologically 6 weeks after SCI. Stereological quantification was performed on the spinal cords to determine donor cell (MSCs transduced with the LacZ gene) density in the lesions. Light microscopic examination revealed that cavitation in the contused spinal cords was less in the MSC-treated rats. A limited number of cells derived from MSCs (LacZ(+)) in the injury site expressed neural or glial markers. Functional outcome measurements using the Basso-Beattie-Bresnehan (BBB) score were performed periodically up to 6 weeks post-SCI. Locomotor recovery improvement was greater in the MSC-treated groups than in sham controls with greatest improvement in the earlier post-contusion infusion times. The availability of autologous MSCs in large number and the potential for systemically delivering cells to target lesion areas without neurosurgical intervention suggests the potential utility of intravenous cell delivery as a prospective therapeutic approach in acute and subacute SCI.

Quantitative analysis of adverse events in neurosurgery.

OBJECTIVE: : It is well recognized that the occurrence rate of adverse events related to surgical procedures is considerably high in neurosurgery compared with other specialties. The purpose of this study was to quantitatively determine the occurrence rate of adverse events related to surgery and endovascular intervention in neurosurgery. METHODS: A conference on adverse events related to treatments (morbidity and mortality conference) has been held every month for the past 2 years in our department. At these conferences, all adverse events are evaluated and discussed. Adverse events include not only the unexpected complications, but also the neurological and general deterioration predicted before surgery. All the adverse events are discussed in terms of the conceivable causes, their association with the procedures, and the possibility of prediction and avoidance. RESULTS: One hundred eighty-two events (28.3%) among 643 neurosurgical interventions over 2 years were recognized as adverse events. Among these 182 adverse events, 165 (90.7%) were closely related to procedures and 125 events (68.7%) were predictable before or during the procedures. However, even when retrospectively reviewed, only 6 (3.3%) of events were deemed avoidable. Of these 6 avoidable events, there were only 2 (1.1%) that were considered to have been caused by error. CONCLUSION: Adverse events are not invariably rare in neurosurgery. Most of them are predictable; however, their avoidance is not necessarily easy. Avoidable adverse events caused by medical errors were observed in only 1.1% of cases.