Potential of machine learning to predict early ischemic events after carotid endarterectomy or stenting: a comparison with surgeon predictions.

Carotid endarterectomy (CEA) and carotid artery stenting (CAS) are recommended for high stroke-risk patients with carotid artery stenosis to reduce ischemic events. However, we often face difficulty in determining the best treatment strategy. We aimed to develop an accurate post-CEA/CAS outcome prediction model using machine learning that will serve as a basis for a new decision support tool for patient-specific treatment planning. Retrospectively collected data from 165 consecutive patients with carotid stenosis underwent CEA or CAS and were divided into training and test samples. The following five machine learning algorithms were tuned, and their predictive performance was evaluated by comparison with surgeon predictions: an artificial neural network, logistic regression, support vector machine, random forest, and extreme gradient boosting (XGBoost). Seventeen clinical factors were introduced into the models. Outcome was defined as any ischemic stroke within 30 days after treatment including asymptomatic diffusion-weighted imaging abnormalities. The XGBoost model performed the best in the evaluation; its sensitivity, specificity, positive predictive value, and accuracy were 31.9%, 94.6%, 47.2%, and 86.2%, respectively. These statistical measures were comparable to those of surgeons. Internal carotid artery peak systolic velocity, low-density lipoprotein cholesterol, and procedure (CEA or CAS) were the most contributing factors according to the XGBoost algorithm. We were able to develop a post-procedural outcome prediction model comparable to surgeons in performance. The accurate outcome prediction model will make it possible to make a more appropriate patient-specific selection of CEA or CAS for the treatment of carotid artery stenosis.

Geranylgeranylacetone attenuates cerebral ischemia-reperfusion injury in rats through the augmentation of HSP 27 phosphorylation: a preliminary study.

BACKGROUND: We previously reported that heat shock protein 27 (HSP27) phosphorylation plays an important role in the activation of glucose-6-phosphate dehydrogenase (G6PD), resulting in the upregulation of the pentose phosphate pathway and antioxidant effects against cerebral ischemia-reperfusion injury. The present study investigated the effect of geranylgeranylacetone, an inducer of HSP27, on ischemia-reperfusion injury in male rats as a preliminary study to see if further research of the effects of geranylgeranylacetone on the ischemic stroke was warranted. METHODS: In all experiments, male Wistar rats were used. First, we conducted pathway activity profiling based on a gas chromatography-mass spectrometry to identify ischemia-reperfusion-related metabolic pathways. Next, we investigated the effects of geranylgeranylacetone on the pentose phosphate pathway and ischemia-reperfusion injury by real-time polymerase chain reaction (RT-PCR), immunoblotting, and G6PD activity, protein carbonylation and infarct volume analysis. Geranylgeranylacetone or vehicle was injected intracerebroventricularly 3 h prior to middle cerebral artery occlusion or sham operation. RESULTS: Pathway activity profiling demonstrated that changes in the metabolic state depended on reperfusion time and that the pentose phosphate pathway and taurine-hypotaurine metabolism pathway were the most strongly related to reperfusion among 137 metabolic pathways. RT-PCR demonstrated that geranylgeranylacetone did not significantly affect the increase in HSP27 transcript levels after ischemia-reperfusion. Immunoblotting showed that geranylgeranylacetone did not significantly affect the elevation of HSP27 protein levels. However, geranylgeranylacetone significantly increase the elevation of phosphorylation of HSP27 after ischemia-reperfusion. In addition, geranylgeranylacetone significantly affected the increase in G6PD activity, and reduced the increase in protein carbonylation after ischemia-reperfusion. Accordingly, geranylgeranylacetone significantly reduced the infarct size (median 31.3% vs 19.9%, p = 0.0013). CONCLUSIONS: As a preliminary study, these findings suggest that geranylgeranylacetone may be a promising agent for the treatment of ischemic stroke and would be worthy of further study. Further studies are required to clearly delineate the mechanism of geranylgeranylacetone-induced HSP27 phosphorylation in antioxidant effects, which may guide the development of new approaches for minimizing the impact of cerebral ischemia-reperfusion injury.

Outcome and effect of endovascular treatment in stroke associated with acute extracranial internal carotid artery occlusion: Single-center experience in Japan.

BACKGROUND: Positive data from several randomized controlled trials (RCTs) of endovascular treatment (EVT) for acute ischemic stroke (AIS) patients with anterior circulation large vessel occlusion (ACLVO) have emerged. However, little evidence exists on EVT for acute extracranial internal carotid artery (EC-ICA) occlusion. We therefore analysed the outcome and effect of EVT on AIS due to ACLVO caused by EC-ICA occlusion, including tandem occlusion compared with that caused by pure intracranial artery occlusion. METHODS: A total of 135 consecutive AIS patients with ACLVO between July 2014 and December 2017 were identified. We retrospectively analysed the efficacy of EVT for ACLVO after introducing a stent retriever (SR). We classified ACLVO into the following categories: group A, intracranial artery occlusion without EC-ICA occlusion (pure intracranial artery occlusion), and group B, ipsilateral EC-ICA occlusion with/without intracranial artery occlusion. RESULTS: In total, 65 patients were enrolled. Group A comprised 71% (46/65) of all cases. No difference was observed in terms of age, National Institute of Health Stroke Scale (NIHSS) score, Alberta Stroke Program Early Computed Tomography Score-Diffusion Weighted imaging (ASPECTS-DWI), several clinical time intervals, rate of successful revascularization (74% versus 84%), and rate of functional independence (42% versus 39%) between groups A and B. In all patients, an ASPECTS-DWI ≥6 and an onset-to-door time ≤6 h were associated with good outcome, whereas intracranial artery occlusion without EC-ICA occlusion (pure intracranial artery occlusion) was not. CONCLUSIONS: The outcomes support the efficacy of EVT in stroke associated with acute EC-ICA occlusion. In the EVT of AIS due to ACLVO, there was no significant difference in the results between ipsilateral EC-ICA occlusion with/without intracranial artery occlusion and intracranial artery occlusion without EC-ICA occlusion (pure intracranial artery occlusion).

Stroke Systems of Care During the COVID-19 Epidemic in Kobe City.

BACKGROUND: The novel coronavirus disease 2019 (COVID-19) outbreak raised concerns over healthcare systems' ability to provide suitable care to stroke patients. In the present study, we examined the provision of stroke care in Kobe City during the COVID-19 epidemic, where some major stroke centers ceased to provide emergency care. METHODS: This was a cross-sectional study. The Kobe Stroke Network surveyed the number of stroke patients admitted to all primary stroke centers (PSCs) in the city between March 1 and May 23, 2020, and between March 3 and May 25, 2019. In addition, online meetings between all PSC directors were held regularly to share information. The survey items included emergency response system characteristics, number of patients with stroke hospitalized within 7 days of onset, administered treatment types (IV rt-PA, mechanical thrombectomy, surgery, and endovascular therapy), and stroke patients with confirmed COVID-19. RESULTS: During the period of interest in 2020, the number of stroke patients hospitalized across 13 PSCs was 813, which was 15.5% lower than that during the same period of 2019 (p = 0.285). The number of patients admitted with cerebral infarction, intracerebral hemorrhage, and subarachnoid hemorrhage decreased by 15.4% (p = 0.245), 16.1% (p = 0.659), and 14.0% (p = 0.715), respectively. However, the rates of mechanical thrombectomy and surgery for intracerebral hemorrhage were slightly increased by 12.1% (p = 0.754) and 5.0% (p = 0.538), respectively. PSCs that ceased to provide emergency care reported a decrease in the number of stroke cases of 65.7% compared with the same period in 2019, while other PSCs reported an increase of 0.8%. No case of a patient with stroke and confirmed COVID-19 was reported during the study period. CONCLUSION: Kobe City was able to maintain operation of its stroke care systems thanks to close cooperation among all city PSCs and a temporal decrease in the total number of stroke cases.

MicroRNA regulating stanniocalcin-1 is a metastasis and dissemination promoting factor in glioblastoma.

BACKGROUND: MicroRNAs (miRs) regulate many biological processes, such as invasion, angiogenesis, and metastasis. Glioblastoma (GBM) patients with metastasis/metastatic dissemination have a very poor prognosis; therefore, inhibiting metastasis/metastatic dissemination has become an important therapeutic strategy for GBM treatment. METHODS: Using 76 GBM tissues, we examined the expression levels of 23 GBM-related miRs and compared the miRs' expression levels between GBMs with metastasis/metastatic dissemination and GBMs without metastasis/metastatic dissemination. Using the bioinformatics web site, we searched the target genes of miRs. To analyze the function of target gene, several biological assays and survival analysis by the Kaplan-Meier method were performed. RESULTS: We found that eight miRs were significantly decreased in GBM with metastasis/metastatic dissemination. By the bioinformatics analysis, we identified stanniocalcin-1 (STC1) as the most probable target gene against the combination of these miRs. Four miRs (miR-29B, miR-34a, miR-101, and miR-137) have predictive binding sites in STC1 mRNA, and mRNA expression of STC1 was downregulated by mimics of these miRs. Also, mimics of these miRs and knockdown of STC1 by siRNA suppressed invasion in GBM cells. GBM with metastasis/metastatic dissemination had significantly higher levels of STC1 than GBM without metastasis/metastatic dissemination. Finally, Kaplan-Meier analysis demonstrated that GBMs with high STC1 level had significantly shorter survival than GBMs with low STC1 level. CONCLUSIONS: STC1 may be a novel metastasis/metastatic dissemination promoting factor regulated by several miRs in GBM. Because STC1 is a secreted glycoprotein and functions via the autocrine/paracrine signals, inhibiting STC1 signal may become a novel therapeutic strategy for GBM.

Myo-inositol concentration in MR spectroscopy for differentiating high grade glioma from primary central nervous system lymphoma.

It is sometimes difficult to distinguish gliomas from other tumors on routine imaging. In this study, we assessed whether 3-T magnetic resonance spectroscopy (MRS) with LCModel software might be useful for discriminating glioma from other brain tumors, such as primary central nervous system lymphomas (PCNSLs) and metastatic tumors. A total of 104 cases of brain tumor (66 gliomas, 20 PCNSLs, 6 metastatic tumors, 12 other tumors) were preoperatively investigated with short echo time (35 ms) single-voxel 3-T MRS. LCModel software was used to evaluate differences in the absolute concentrations of choline, N-acetylaspartate, N-acetylaspartylglutamate, glutamate + glutamine, myo-inositol (mIns), and lipid. mIns levels were significantly increased in high-grade glioma (HGG) compared with PCNSL (p < 0.001). In multivariate logistic regression analysis, mIns was the best marker for differentiating HGG from PCNSL (p < 0.0001, odds ratio 1.9927, 95% confidence interval 1.3628-3.2637). Conventional MRS detection of mIns resulted in a high diagnostic accuracy (sensitivity, 64%; specificity, 90%; area under the receiver operator curve, 0.80) for HGG. The expression of inositol 3-phosphate synthase (ISYNA1) was significantly higher in gliomas than in PCNSLs (p < 0.05), suggesting that the increased level of mIns in glioma is due to high expression of ISYNA1, the rate-limiting enzyme in the mIns-producing pathway. In conclusion, noninvasive analysis of mIns using single-voxel MRS may be useful in distinguishing gliomas from other brain tumors, particularly PCNSLs.

Cognard Type V Dural Arteriovenous Fistula Involving the Occipital Sinus.

The Cognard type V dural arteriovenous fistula (dAVF), which has a drainage route into the spinal vein, is a rare subtype of cranial dAVF. Because of typical features such as progressive myelopathy and brainstem dysfunctions, aggressive treatments should be considered. To eliminate venous congestion of the spinal cord, various approaches including surgical interruption of the spinal draining vein or transarterial embolization with cyanoacrylate have been reported. The introduction of nonadhesive Onyx has changed the treatment of dAVF, although little is known about the clinical usefulness of this type of fistula. We describe a case of the Cognard type V dAVF, draining into the spinal vein through the occipital sinus (OS) successfully treated by transarterial double catheter injection of Onyx. We used the alternating injections from 2 microcatheters until the Onyx reached the OS and reflowed into feeders adequately. This technique contributed to the elimination of the remaining afferent flow in an early stage of Onyx injection and achieved enough penetration into the draining vein.

Mechanical Thrombectomy for Acute Ischemic Stroke Patients Aged 80 Years or Older.

BACKGROUND: There are limited data about the prognostic factors predicting outcomes after mechanical thrombectomy with stent retrievers for the elderly. Here, we evaluated outcomes in elderly patients in a real-world setting. METHODS: Between April 2015 and January 2017, 80 patients with anterior intracranial acute large vessel occlusion, who had lived independently before ictus, were treated with mechanical thrombectomy using a stent retriever at our institute. We compared outcomes between patients ≥80 years old (n = 36) and those <80 years old (n = 44), and assessed prognostic factors for favorable outcomes (modified Rankin Scale score 0-2) at 90 days in all patients. RESULTS: There was no significant difference in baseline National Institutes of Health Stroke Scale score and Alberta Stroke Program Early Computed Tomography Score between the 2 groups. Successful revascularization (modified Thrombolysis in Cerebral Infarction [mTICI] scores 2b/3) (83% versus 93%, P = .286), complete recanalization (mTICI 3) (47% versus 50%, P = .826), and favorable outcomes (42% versus 57%, P = .261) were achieved more often in those <80 years old, but differences did not reach statistical significance. Multivariate regression analysis showed that baseline National Institutes of Health Stroke Scale (P = .013) and mTICI scores of 3 (P = .006) were significant predictive factors, but being ≥80 years old and baseline Alberta Stroke Program Early Computed Tomography Score were not. In those ≥80 years old, mTICI score of 3 was an influential factor for favorable outcome (P = .017). CONCLUSIONS: Being aged 80 years or older was not a significant predictor for outcomes after mechanical thrombectomy, whereas complete recanalization was an influential predictor of outcome in the elderly.

Early endovascular stenting for extracranial carotid artery dissection with angiographic flow stasis: A series of four cases.

Extracranial carotid artery dissection is a major cause of ischemic stroke in young patients. Progressive stroke or recurrent ischemic symptoms may occur despite adequate medical treatment. Our treatment policy for these conditions is based on the fact that immediate vascular reconstruction is necessary in the cases with angiographic flow stasis in the true lumen beyond the dissection site. We report our experiences with four consecutive extracranial carotid artery dissections successfully treated with early endovascular stenting and discuss the indication of this treatment with a special emphasis on the angiographic findings.

Cerebral angiitis associated with subarachnoid hemorrhage in Castleman's disease: report of two cases.

BACKGROUND: Multicentric Castleman's disease (MCD) is characterized by a systemic lymphoproliferative disorder affecting systemic lymph nodes. Cerebrovascular involvements have rarely been reported, and to our knowledge, cerebral angiitis causing subarachnoid hemorrhage (SAH) in patients with Multicentric Castleman's disease (MCD) has not been previously described. CASE PRESENTATION: We identified two cases of MCD with SAH who were receiving immunosuppressive therapy with low dose prednisolone. Both patients presented with sudden-onset headache and were diagnosed with cortical SAH in the sulci by a computed tomography scan. Digital subtraction angiography showed segmental stenosis in the peripheral area of the middle cerebral artery. In both cases, cerebral angiitis causing SAH induced by a systemic inflammatory condition and elevated levels of interleukin (IL) -6 were suspected and resolved over a period of several months. CONCLUSION: Our cases highlight the clinical diversity of the potential causes of cerebral angiitis and expand the association of MCD and cortical SAH; however, cortical SAH patients have a more favorable outcome than aneurysmal SAH patients.

Duplex-assisted carotid artery stenting without administration of contrast medium for patients with chronic kidney disease or allergic reaction.

INTRODUCTION: We aimed to investigate the safety and feasibility of duplex-assisted carotid artery stenting (CAS) without administration of contrast medium for the prevention of adverse reactions. METHODS: Fifteen patients (9 % of all CASs) with severe carotid stenosis (≥70 %) associated with chronic kidney disease (CKD) (stage ≥3) or allergy to contrast medium underwent duplex-assisted CAS without administration of contrast medium over 4 years. The procedural success rate and perioperative complication rates were compared between the duplex-assisted CAS (n = 15) and conventional CAS (n = 153) groups. RESULTS: The technical success rate was 100 % in both groups. Combined stroke or death rates during the post-procedural period did not differ significantly between the duplex-assisted CAS group (0/15, 0 %) and conventional CAS group (4/153, 2.6 %). None of the 14 patients with CKD in the duplex-assisted CAS group experienced further deterioration of renal function. The mean surface radiation dose of participants in the duplex-assisted CAS group (n = 13, 312 ± 131 mGy) was significantly lower than that of the conventional CAS group (n = 31, 1036 ± 571 mGy) (p < 0.001). The mean duration of CAS procedure was not significantly different between the duplex-assisted CAS group (156 ± 39.7 min) and the conventional CAS group (156 ± 37.4 min). CONCLUSION: Duplex-assisted CAS without administration of contrast medium could be an alternative option in selected patients deemed to be at high risk for renal failure from nephrotoxic contrast medium or who have an allergy to contrast medium.

Endovascular Internal Trapping of Ruptured Occipital Artery Pseudoaneurysm Associated with Occipital-Internal Jugular Vein Fistula in Neurofibromatosis Type 1.

Spontaneous cervical extradural pseudoaneurysms or arteriovenous fistulas (AVFs) are rare vascular diseases. We report a case of ruptured occipital artery (OA) pseudoaneurysm associated with occipital-internal jugular vein (IJV) fistula in neurofibromatosis type 1. Endovascular internal trapping via the OA was attempted; however, the distal entry of the OA could not be accessed because of the high shunt flow and tortuosity of the OA. The distal part of the OA was obliterated with coil via a transvenous approach through the IJV and pseudoaneurysm. The proximal entry of the OA was obliterated with coil and glue under proximal flow control with a balloon, and the fistula was successfully obliterated without placement of coils in the pseudoaneurysm. When ordinary internal trapping via a transarterial approach is not possible, the transvenous approach should be considered as an alternative for AVF associated with an aneurysmal component.

Long-Term Outcomes of Carotid Endarterectomy and Carotid Artery Stenting for Carotid Artery Stenosis: Real-World Status in Japan.

BACKGROUND AND PURPOSE: We investigated long-term outcomes of carotid endarterectomy (CEA) and carotid artery stenting (CAS) in our institute to evaluate the outcomes of real-world practice in Japan. METHODS: Between August 2006 and July 2013, 203 consecutive carotid revascularizations with either CEA or CAS were performed in our institute. The initial treatment was regarded as the starting point in the cases of the patients who received treatment by bilateral carotid artery stenosis or retreatment. We assessed the long-term outcomes with survival analyses. RESULTS: A total of 182 patients (CEA 111, CAS 71), including 86 symptomatic patients, were included in the current study with a mean follow-up period of 42.9 months. The periprocedural stroke/death/myocardial infarction (MI) rate was 3.6% for CEA and 5.6% for CAS groups (P = .71). Estimates of the 4-year event-free rate from the primary end point (the composite of any stroke, death, or MI within 30 days, and any ipsilateral stroke thereafter) using competing risk analysis were 3.6% for CEA and 7.1% for CAS (P = .156). Kaplan-Meier estimates of the 4-year event-free rate from the secondary end point (the composite of any stroke, death, or MI within 30 days, and any stroke or death thereafter) were 13.8% for CEA and 19.1% for CAS (P = .072). Age was the only significant predictor for the primary end point. Both age and CAS were significant predictors for the secondary end point. CONCLUSIONS: The current study on real-world practices demonstrated perioperative and long-term outcomes that were comparable to previous major studies of large numbers of patients.

Endoscopic endonasal transsellar approach for laterally extended pituitary adenomas: volumetric analysis of cavernous sinus invasion.

PURPOSE: The authors conducted a statistical analysis of surgical results of the endoscopic endonasal transsellar approach to provide quantitative indices for selection of the approach in the treatment of laterally extended pituitary adenomas. METHODS: Surgical results of 25 patients with laterally extended pituitary adenomas of Knosp grade 3 or 4 were retrospectively analyzed. The removal rate was evaluated by the volumetric change of the lateral tumor compartment. RESULTS: The transsellar approach was used exclusively in all cases. Gross total removal of the lateral tumor compartment was achieved in 14 (56.0%). Factors affecting the tumor removal through the transsellar approach were lateral tumor volume (p = 0.006), maximal distance to the cavernous sinus outer wall (p = 0.004) and history of previous surgery (p = 0.017). The cut-off values for the lateral tumor volume and maximal distance to the cavernous sinus outer wall predicting the gross total removal were 0.479 ml and 8.1 mm, respectively. The surgical complications of the transsellar approach included each case of anterior lobe function insufficiency and liquorrhea. CONCLUSIONS: The transsellar approach is adequate for removal of lateral tumor compartment in the majority of cases with laterally extended pituitary adenomas. The tumor compartments dorsal and ventral to the horizontal portion of the intracavernous carotid artery are amenable to the removal. But for removal of the tumor compartment lateral to the carotid siphon requires additional use of the parasellar approach.

[Use of heparinized autologous blood for intraoperative rinsing and storage of vascular grafts].

UNLABELLED: In cerebral revascularization surgery in Japan, the preferred solution for rinsing and intraoperative storage of saphenous vein or radial artery grafts is a heparinized saline solution with albumin. On the other hand, most cardiac surgeons routinely use solutions of heparinized autologous blood during surgery. Here we used the latter type of solution for cerebral revascularization surgery and evaluated its efficacy. PATIENTS AND METHODS: Since December 2011, we have used heparinized autologous blood for saphenous vein grafts during cerebral revascularization surgery. For this, 20mL of the whole blood was obtained from an arterial line;this blood was then mixed with 20mL of a heparinized saline solution containing 500IU of heparin and 40mg of papaverine hydrochloride. The saphenous vein was harvested using standard procedures and immersed in the autologous blood solution just before implantation. RESULTS: Between December 2011 and March 2013, six revascularizations using saphenous vein grafts were performed using this solution. None of the anastomoses presented complications related to revascularization procedures, and all grafts were clearly present postoperatively. DISCUSSION: There is still no evidence that the storage in autologous blood is superior to the use of a saline solution with albumin. However, the national health insurance does not cover the use of albumin products, which carries an additional cost. Furthermore, the autologous blood medium is a red-colored solution that indicates the presence of unfavorable graft leaks when the wall of the graft turns red. CONCLUSION: We recommend the use of heparinized autologous blood for intraoperative rinsing and storage grafts.

[Two cases of cerebral infarction due to focal irradiation for glioma in adults].

Radiation-induced vasculopathy is a complication of radiation therapy. Most reports regarding post-irradiation ischemic stroke with intracranial tumors are restricted to pediatric cases. Here we report two adult cases of delayed brain infarction due to anterior and middle cerebral artery stenosis or occlusion seemingly caused by focal radiation therapy for malignant glioma. Although radiation-induced ischemic stroke in adults is relatively uncommon, it is possible that the morbidity rate of radiation-induced stroke in malignant glioma patients will increase with prolonged survival due to advances in therapy. Therefore, regular evaluation of intracranial vasculature following radiation therapy is necessary.

Utility of 320-detector row CT for diagnosis and therapeutic strategy for paraclinoid and intracavernous aneurysms.

BACKGROUND: The aim of this study was (1) to assess the diagnostic accuracy of 320-detector row computed tomography (CT) for paraclinoid and intracavernous aneurysms, and (2) to investigate whether this method provides sufficient information for surgery. METHODS: A total of 14 patients with 16 unruptured proximal ICA aneurysms underwent three-dimensional CT angiography (3D-CTA) fusion imaging, which was created by superimposing 3D-CT venography data and/or 3D-bone data onto 3D-CTA data using 320-detector row CT, magnetic resonance imaging (MRI), and 3D digital subtraction angiography (DSA). The images of each modality were assessed using intraoperative findings as the reference standard. RESULTS: All aneurysms were clearly visualized on 320-detector row CT. Bone subtraction and arterio-venous discrimination were accurate. On 3D-CTA fusion images, 11 aneurysms were diagnosed as "extracavernous" and five as "intracavernous". No discordance in aneurysm location between the 3D-CTA fusion images and the intraoperative findings was found. In contrast, discordance between MRI and intraoperative findings were found in five of the 16 cases (31%), which was significantly more frequent than with 3D-CTA (p = 0.043). The findings DSA, which was performed in nine patients, were also in excellent agreement with the intraoperative findings. However, 3D-CTA fusion imaging provided more comprehensive information, including venous and osseous structures, than 3D-DSA. The 320-detector row CTA after surgery demonstrated a clear relationship between the clip and aneurysmal neck with notably few artifacts, which suggested the utility of this modality for postoperative assessment. CONCLUSIONS: The 320-detector row CT provided high accuracy for the diagnosis of paraclinoid and intracavernous aneurysms. This technique also provided comprehensive depiction of the aneurysms and surrounding structures. Therefore, this modality might be useful for the diagnosis of the paraclinoid and intracavernous aneurysms and for developing a surgical treatment plan.

Predicting impaired cerebrovascular reactivity and risk of hyperperfusion syndrome in carotid artery stenosis using BeamSAT magnetic resonance imaging.

Pencil-beam presaturation (BeamSAT) magnetic resonance imaging (MRI) produces selective magnetic resonance angiography (MRA) images of specific arteries, including the unilateral internal carotid artery (ICA-selective MRA) or vertebral artery (VA-selective MRA). We evaluate the influence of flow pattern, visualized using BeamSAT MRI, on preoperative cerebral hemodynamic status and postoperative hyperperfusion syndrome (HPS). Patients undergoing carotid artery stenting or carotid endarterectomy were categorized into two groups to evaluate flow pattern. Patients with neither crossflow on BeamSAT MRI nor mismatch in middle cerebral artery (MCA) signal intensity between ICA-selective and conventional MRA were classified into Group I, comprising 29 patients. Group II included all other patients comprising 19 patients, who were suspected of experiencing changes in intracranial flow patterns. Cerebral blood flow and cerebrovascular reactivity (CVR) were assessed using single-photon emission computed tomography, and potential HPS symptoms were retrospectively assessed by chart review. Preoperative ipsilateral CVR was significantly lower in Group II than in Group I (18.0% ± 20.0% vs. 48.3% ± 19.5%; P < 0.0001). Group II showed significantly impaired CVR (odds ratio 17.7, 95% confidence interval 1.82-171; P = 0.013) in multivariate analysis. The partial areas under the curve of the BeamSAT logistic model (0.843) were significantly larger than those of the conventional logistic model (0.626) over the range of high sensitivity (0.6-1) (P = 0.04). The incidence of postoperative HPS symptoms was significantly higher in Group II than in Group I (8/19 vs. 1/29; P = 0.001). BeamSAT MRI may be a valuable and non-invasive tool for assessing cerebral hemodynamics and predicting postoperative HPS.

Successful shrinkage of a recurrent partially thrombosed symptomatic large basilar tip aneurysm using a Target 3D Coil.

Background: Standalone coil embolization is often less effective for partially thrombosed intracerebral aneurysms (PTIA) because of the risk of frequent recurrence if the coil migrates into the thrombus. This report describes a case of PTIA at the basilar tip in which simple coil embolization using a Target 3D Coil resulted in sustained remission without recurrence during long-term follow-up. Case Description: The patient was a 63-year-old male who presented with right oculomotor nerve palsy after having undergone direct surgery for a basilar artery aneurysm 15 years earlier. Recurrence with partial thrombosis of the basilar artery aneurysm was diagnosed. Target 3D Coil embolization with frame construction in the aneurysmal sac was performed, resulting in the complete disappearance of the aneurysm and improvement of the oculomotor nerve palsy. Magnetic resonance imaging at five years postoperatively confirmed that the thrombus had completely disappeared, and there was no recurrence of the aneurysm. The closed loops in the Target 3D Coil may have contributed to the cohesive mass of coils remaining in the sac of the PTIA, potentially leading to healing. Conclusion: The characteristics of the Target 3D Coil may have prevented migration of the coil into the thrombus, potentially contributing to the successful resolution of the aneurysm.

MicroRNA-183 upregulates HIF-1α by targeting isocitrate dehydrogenase 2 (IDH2) in glioma cells.

MicroRNAs (miRs) are small, non-coding RNAs that regulate gene expression and contribute to cell proliferation, differentiation and metabolism. Our previous study revealed the extensive modulation of a set of miRs in malignant glioma. In that study, miR microarray analysis demonstrated the upregulation of microRNA-183 (miR-183) in glioblastomas. Therefore, we examined the expression levels of miR-183 in various types of gliomas and the association of miR-183 with isocitrate dehydrogenase 2 (IDH2), which has complementary sequences to miR-183 in its 3'-untranslated region (3'UTR). In present study, we used real-time PCR analysis to demonstrate that miR-183 is upregulated in the majority of high-grade gliomas and glioma cell lines compared with peripheral, non-tumorous brain tissue. The mRNA and protein expression levels of IDH2 are downregulated via the overexpression of miR-183 mimic RNA in glioma cells. Additionally, IDH2 mRNA expression is upregulated in glioma cells expressing anti-miR-183. We verified that miR-183 directly affects IDH2 mRNA levels in glioma cells using luciferase assays. In malignant glioma specimens, the expression levels of IDH2 were lower in tumors than in the peripheral, non-tumorous brain tissues. HIF-1α levels were upregulated in glioma cells following transfection with miR-183 mimic RNA or IDH2 siRNA. Moreover, vascular endothelial growth factor and glucose transporter 1, which are downstream molecules of HIF-1α, were upregulated in cells transfected with miR-183 mimic RNA. These results suggest that miR-183 upregulation in malignant gliomas induces HIF-1α expression by targeting IDH2 and may play a role in glioma biology.