Intellectual function and memory in children with moyamoya disease: relationship between Wechsler Intelligence Scale and Benton Visual Retention Test scores and regional cerebral blood flow

OBJECTIVE

Intellectual function declines in about 30% of children with moyamoya disease (MMD). Memory function underpins higher order brain function, but the relationship between intellectual function and memory in pediatric MMD patients has not been well studied. This study aimed to investigate correlations between scores on the Wechsler Intelligence Scale for Children (WISC) and the Benton Visual Retention Test (BVRT), a visual memory test that can be administered to children, in children with MMD. Relationships between intellectual function or memory and regional cerebral blood flow (rCBF) have also not been well clarified in pediatric MMD patients. The authors also investigated associations between WISC or BVRT scores and rCBF in various brain regions.

METHODS

WISC and BVRT scores and rCBF were assessed in 17 children with ischemic-onset MMD before revascularization. Single-photon emission CT with 123I-iodoamphetamine was used to measure rCBF. Relationships between WISC and BVRT scores were evaluated using Spearman's correlation coefficient and multivariate linear regression analysis. Cutoff values were identified for BVRT scores. Sensitivity and specificity were calculated to predict full-scale intelligence quotient (FSIQ) > 85 or ≤ 85. Associations between rCBF and WISC or BVRT scores were evaluated using linear regression analysis.

RESULTS

BVRT scores were significantly correlated with FSIQ and scores on the Working Memory Index (WMI), Processing Speed Index, and Verbal Comprehension Index (VCI)/Verbal Intelligence Quotient (VIQ) of WISC. Multivariate linear regression revealed that number correct score and number of errors score of BVRT were associated with FSIQ. As cutoff values, a number correct score of 5 and a number of errors score of 8 offered the most reliable predictors of FSIQ > 85 and ≤ 85, respectively. FSIQ correlated positively with rCBF in the right and left hemispheres, right and left ganglia, right and left thalamus, right and left cerebellum, right middle cerebral artery (MCA) territory, pons, and vermis. WMI score was positively associated with rCBF in the right hemisphere, right anterior cerebral artery territory, right MCA territory, right basal ganglia, right and left thalamus, right and left cerebellum, pons, and vermis.

CONCLUSIONS

BVRT score correlated well with WISC index scores, suggesting that BVRT may be helpful in screening for intellectual impairments in children with MMD. In the MCA territory, basal ganglia, thalamus, cerebellum, pons, and vermis, rCBF associated well with WISC index scores, suggesting that reduced rCBF in relevant brain regions may influence intellectual function.

Brain volume measured by synthetic magnetic resonance imaging in adult moyamoya disease correlates with cerebral blood flow and brain function

Moyamoya disease (MMD) is characterized by progressive arterial occlusion, causing chronic hemodynamic impairment, which can reduce brain volume. A novel quantitative technique, synthetic magnetic resonance imaging (SyMRI), can evaluate brain volume. This study aimed to investigate whether brain volume measured with SyMRI correlated with cerebral blood flow (CBF) and brain function in adult MMD. In this retrospective study, 18 adult patients with MMD were included. CBF was measured using iodine-123-N-isopropyl-p-iodoamphetamine single photon emission computed tomography. Cerebrovascular reactivity (CVR) to acetazolamide challenge was also evaluated. Brain function was measured using the Wechsler Adult Intelligence Scales (WAIS)-III/IV and the WAIS-R tests. Gray matter (GM), white matter, and myelin-correlated volumes were evaluated in six areas. Resting CBF was positively correlated with GM fractions in the right anterior cerebral arterial and right middle cerebral arterial (MCA) territories. CVR was positively correlated with GM fraction in the right posterior cerebral arterial (PCA) territory. Full-Scale Intelligence Quotient and Verbal Comprehension Index scores were marginally positively correlated with GM fractions in the left PCA territory. Processing Speed Index score was marginally positively correlated with GM fraction in the right MCA territory. The SyMRI-measured territorial GM fraction correlated with CBF and brain function in patients with MMD.

Liquid Biopsy for Glioma Using Cell-Free DNA in Cerebrospinal Fluid

Glioma is one of the most common primary central nervous system (CNS) tumors, and its molecular diagnosis is crucial. However, surgical resection or biopsy is risky when the tumor is located deep in the brain or brainstem. In such cases, a minimally invasive approach to liquid biopsy is beneficial. Cell-free DNA (cfDNA), which directly reflects tumor-specific genetic changes, has attracted attention as a target for liquid biopsy, and blood-based cfDNA monitoring has been demonstrated for other extra-cranial cancers. However, it is still challenging to fully detect CNS tumors derived from cfDNA in the blood, including gliomas, because of the unique structure of the blood-brain barrier. Alternatively, cerebrospinal fluid (CSF) is an ideal source of cfDNA and is expected to contribute significantly to the liquid biopsy of gliomas. Several successful studies have been conducted to detect tumor-specific genetic alterations in cfDNA from CSF using digital PCR and/or next-generation sequencing. This review summarizes the current status of CSF-based cfDNA-targeted liquid biopsy for gliomas. It highlights how the approaches differ from liquid biopsies of other extra-cranial cancers and discusses the current issues and prospects.

Memory, Executive, and Intellectual Functions in Adults with Moyamoya Disease

OBJECTIVE

Cognitive function can decline in adults with moyamoya disease (MMD). Memory, which is an essential but complex and multifaceted function, underpins executive and intellectual functions. However, the relationship between memory and executive or intellectual functions in adults with MMD has not been well studied. The relationship between memory and cerebral blood flow has also not been elucidated. This study investigated correlations between memory, executive function, and intellectual function, and associations between cerebral blood flow and memory in adults with MMD.

METHODS

Memory, executive function, and intellectual function were assessed using the Wechsler Memory Scale-Revised (WMS-R), Frontal Assessment Battery (FAB), and Wechsler Adult Intelligence Scale (WAIS) third or fourth edition, respectively, in 31 adults with MMD. Cerebral blood flow was measured with iodine 123I-iodoamphetamine single-photon emission computed tomography.

RESULTS

WMS-R scores correlated significantly with total FAB and WAIS scores before and after revascularization. Cerebral blood flow in the left posterior cerebral artery territory correlated positively with WMS-R and WAIS scores pre- and postoperatively. Postoperative cerebrovascular reserves of the right cerebellum, pons, and vermis were positively associated with visual memory, and postoperative cerebrovascular reserve of the pons was also associated with general memory.

CONCLUSIONS

Memory function correlates with executive and intellectual functions in adults with MMD. The FAB, which requires about 10 min to administer, might be useful to screen for memory dysfunction. Memory might be vulnerable to hypoperfusion in the posterior cerebral artery territory among adults with MMD. Postoperative cerebrovascular reserve might help predict memory dysfunction in adults with MMD.

A cavernous sinus dural arteriovenous fistula treated by direct puncture of the superior ophthalmic vein with craniotomy: illustrative case

BACKGROUND

The authors report a case of symptomatic cavernous sinus (CS) dural arteriovenous fistula (dAVF) that was successfully treated using direct puncture of the superior ophthalmic vein (SOV) with craniotomy. CS dAVF is commonly treated using transvenous embolization (TVE), with the most common access route via the inferior petrosal sinus (IPS). However, this route is sometimes unavailable because of an occluded, hypoplastic, aplastic, or tortuous IPS. The SOV is an alternative, albeit tortuous and long, route to the CS; therefore, direct SOV puncture is occasionally performed. Direct SOV puncture is mostly percutaneous; however, in this case, it was difficult because of subcutaneous SOV narrowing.

OBSERVATIONS

As the patient experienced increased intraocular pressure, decreased vision, and eye movement disorders, CS embolization was performed via direct puncture with a craniotomy because of other access difficulties.

LESSONS

Several reports have described CS dAVF in patients receiving endovascular treatment via direct SOV puncture using a transorbital approach. However, to the best of the authors' knowledge, this is the first reported case of a CS dAVF treated using TVE with craniotomy. This approach is useful when the SOV cannot be reached intravenously and its distance from the epidermis is long.

Percutaneous transluminal angioplasty for persistent primitive hypoglossal artery stenosis: illustrative case

BACKGROUND

We report a case of symptomatic, progressive stenosis of a persistent primitive hypoglossal artery (PPHA), which was successfully treated with percutaneous transluminal angioplasty (PTA) of the origin of the PPHA. The PPHA is a type of carotid-basilar anastomosis with an incidence of 0.02% to 0.10%. It originates from the internal carotid artery (ICA), passes through the hypoglossal canal, and merges with the basilar artery. In many cases, the ipsilateral vertebral artery is hypoplastic; therefore, PPHA stenosis causes cerebral infarction in the posterior circulation territory, as in this case.

OBSERVATIONS

The patient's right PPHA had severe and progressive stenosis; therefore, he experienced cerebral infarction despite medical treatment. Therefore, PTA for the stenosis was performed, which ceased the recurrence of cerebral infarction and dizziness by improving blood flow in the posterior circulation.

LESSONS

Several reports have described ICA stenosis accompanied by PPHA or PPHA stenosis in patients receiving endovascular treatments. Almost all cases were nonprogressive, and the treatment procedure was stenting. However, in our case, the PPHA stenosis was progressive, and we performed PTA because the patient experienced resistance to antiplatelet drugs and had poor collateral flow.

Hemifacial Spasm Caused by Vascular Compression of the Anterior Inferior Cerebellar Artery-Posterior Inferior Cerebellar Artery Common Trunk Anomaly at the Cisternal Portion of the Facial Nerve: A Case Report

W report the first case of hemifacial spasm (HFS) caused by vascular compression of the anterior inferior cerebellar artery (AICA)-posterior inferior cerebellar artery (PICA) common trunk anomaly at the cisternal portion of cranial nerve VII (CN VII). A 71-year-old female with a typical right HFS was admitted to our hospital. As per her magnetic resonance (MR) imaging results, no offending arteries were noted around the CN VII root exit zone (REZ). Computed tomography angiography revealed an AICA-PICA common trunk anomaly with a dominant PICA, with the rostral branch of the AICA-PICA common trunk anomaly compressing the CN VII at the cisternal portion. The patient underwent microvascular decompression (MVD), and the HFS disappeared after surgery. The amplitude of the abnormal muscle responses (AMR) disappeared immediately after complete transposition of the offending artery. However, the patient experienced mild transient facial palsy 3 days after MVD which was eventually resolved with the administration of vitamin B12. No HFS recurrence was observed during the 1-year follow-up period. The AICA-PICA common trunk anomaly has been found to cause HFS as it compressed the CN VII at the cisternal portion, and not at the REZ. AMR monitoring might be helpful for cases where the unusual vessel particularly compresses the CN VII.

Angiogenic and inflammatory responses in human induced microglia-like (iMG) cells from patients with Moyamoya disease

Angiogenic factors associated with Moyamoya disease (MMD) are overexpressed in M2 polarized microglia in ischemic stroke, suggesting that microglia may be involved in the pathophysiology of MMD; however, existing approaches are not applicable to explore this hypothesis. Herein we applied blood induced microglial-like (iMG) cells. We recruited 25 adult patients with MMD and 24 healthy volunteers. Patients with MMD were subdivided into progressive (N = 7) or stable (N = 18) group whether novel symptoms or radiographic advancement of Suzuki stage within 1 year was observed or not. We produced 3 types of iMG cells; resting, M1-, and M2-induced cells from monocytes, then RNA sequencing followed by GO and KEGG pathway enrichment analysis and qPCR assay were performed. RNA sequencing of M2-induced iMG cells revealed that 600 genes were significantly upregulated (338) or downregulated (262) in patients with MMD. Inflammation and immune-related factors and angiogenesis-related factors were specifically associated with MMD in GO analysis. qPCR for MMP9, VEGFA, and TGFB1 expression validated these findings. This study is the first to demonstrate that M2 microglia may be involved in the angiogenic process of MMD. The iMG technique provides a promising approach to explore the bioactivity of microglia in cerebrovascular diseases.

Abstract TP133: Efficacy Of Mechanical Thrombectomy For The Posterior Circulation Stroke

Background and Purpose: The efficacy of mechanical thrombectomy (MT) for posterior circulation large vessel occlusions has not been fully elucidated. We investigated the efficacy and safety of MT for posterior circulation stroke (PCS) compared with anterior circulation stroke (ACS).

Methods: We analyzed 885 consecutive patients who underwent MT for acute ischemic stroke between January 2013 and December 2020 at six comprehensive stroke centers. The patients were divided into two groups; the PCS and ACS group. The procedural and clinical outcomes were compared between the groups.

Results: A total of 767 patients (PCS group, 83; ACS group, 684), were analyzed. PCS patients were significantly younger (75 vs. 79, P = 0.008) and had a higher NIHSS score at baseline (23 vs 19, p=0.012) and longer door to puncture time (97 vs 73 min, p=0.009). The rate of male (67.0 vs 46.9% p<0.001) and atherosclerotic brain infarction (22.8 vs 8.3% p<0.001) were higher, comorbid atrial fibrillation (50.6 vs 64.4% p=0.022) was fewer in the PCA group. The rate of mTICI 3 recanalization at the first pass (40.9 vs 28.5% p=0.019) was significantly higher in the PCS group. However, the rates of final mTICI ≥ 2b recanalization (86.6 vs 83.8% p=0.491), symptomatic hemorrhagic complications, good clinical outcome at 90 days (34.3 vs 32.5% p=0.767), and mortality (22.3 vs 16% p=0.184) were similar in the groups. In the PCS group, the single use of a stent retriever for the first pass was associated with higher mortality rate compared with use of ADAPT or combined technique (38.6 vs 12.2% p=0.012).

Conclusions: MT for PCS seemed to be beneficial, having similar complication, recanalization rate, and clinical outcomes with ACS.

Different hemodynamics of basal ganglia between moyamoya and non-moyamoya diseases using intravoxel incoherent motion imaging and single-photon emission computed tomography

BACKGROUND

Moyamoya disease (MMD) and non-MMD have different pathogenesis, clinical presentation, and treatment policy.

PURPOSE

To identify differences in hemodynamics between MMD and non-MMD using intravoxel incoherent motion (IVIM) magnetic resonance imaging (MRI) and single-photon emission computed tomography (SPECT).

MATERIAL AND METHODS

Patients who had undergone ^99mTc-ECD or ¹²³I-IMP SPECT, and IVIM imaging were retrospectively studied. IVIM imaging was acquired using six different b-values. Cerebral blood flow ratio (CBF_R) in the basal ganglia was calculated using a standardized volume-of-interest template. The cerebellum was used as a reference region. IVIM perfusion fraction (f) was obtained using a two-step fitting algorithm. Elliptical regions of interest were placed in bilateral basal ganglia on the IVIM f map. Patients were classified into MMD and non-MMD groups. The correlation between CBF_R and mean IVIM f (f_mean) in the basal ganglia was evaluated using Spearman's rank correlation coefficient.

RESULTS

In total, 20 patients with MMD and 28 non-MMD patients were analyzed. No significant differences in f_mean were observed among MMD, affected hemisphere with non-MMD (non-MMD_aff), and unaffected hemispheres with non-MMD (non-MMD_unaff). A negative correlation was seen between f_mean and CBF_R in the MMD group (r = -0.40, P = 0.0108), but not in the non-MMD group (non-MMD_aff, r = 0.07, P = 0.69; non-MMD_unaff, r = -0.22, P = 0.29). No significant differences were found among MMD and non-MMD patients, irrespective of SPECT tracers.

CONCLUSION

The combination of IVIM MRI and SPECT appears to allow non-invasive identification of differences in hemodynamics between MMD and non-MMD.

Abstract TMP88: Prognostic Scoring System Of Mechanical Thrombectomy For Elderly Acute Ischemic Stroke Patients

Background: The number of mechanical thrombectomy (MT) for acute ischemic stroke (AIS) in elderly patients has increased, but the feasibility and safety are still debated. We aimed to investigate the risk factors and produce a prognostic scoring system for MT in elderly AIS patients.

Methods: We analyzed data from 763 consecutive patients who underwent MT for AIS between January 2013 and January 2020 at seven comprehensive stroke centers for derivation group. We defined elderly patients as ≥ 75 years of age. We investigated the risk factors of MT among these elderly patients and developed a prognostic scoring system assigned weighted points proportional to their standardized coefficient values. We conducted a subsequent validation study that included 287 consecutive patients treated between February 2020 and December 2021.

Results: In total, 251 elderly patients in derivation group were analyzed retrospectively. According to the multivariable analysis, we developed a scoring system (SNA 3 P score) consisting of six factors, including age ≥ 90 (2 points), female sex (2 points), a pre-modified Rankin Scale (mRS) score of 2 (1 point), anticoagulant drug use (2 points), the NIHSS score (4 points), and the ASPECTS (4 points). A score ≤ 5 predicted an mRS score of 0-2 at 90 days with a sensitivity of 74% and a specificity of 65%, and the area under the curve (AUC) was 0.76. In the validation study, a score ≤ 5 predicted an mRS score of 0-2 at 90 days with a sensitivity of 70% and a specificity of 60% (AUC was 0.74).

Conclusions: We created the novel scoring system to predict the functional outcome of elderly AIS patients undergoing MT. This simple scoring system may provide the information for indication of MT for elderly AIS patients, but further investigation for external validation is needed.

Liquid biopsy with multiplex ligation-dependent probe amplification targeting cell-free tumor DNA in cerebrospinal fluid from patients with adult diffuse glioma

Background

Copy number alterations (CNAs) are common in diffuse gliomas and have been shown to have diagnostic significance. While liquid biopsy for diffuse glioma has been widely investigated, techniques for detecting CNAs are currently limited to methods such as next-generation sequencing. Multiplex ligation-dependent probe amplification (MLPA) is an established method for copy number analysis in pre-specified loci. In this study, we investigated whether CNAs could be detected by MLPA using patients' cerebrospinal fluid (CSF).

Methods

Twenty-five cases of adult diffuse glioma with CNAs were selected. Cell-free DNA (cfDNA) was extracted from the CSF, and DNA sizes and concentrations were recorded. Twelve samples, which had appropriate DNA sizes and concentrations, were subsequently used for analysis.

Results

MLPA could be successfully performed in all 12 cases, and the detected CNAs were concordant with those detected using tumor tissues. Cases with epidermal growth factor receptor (EGFR) amplification, combination of gain of chromosome 7 and loss of chromosome 10, platelet-derived growth factor receptor alpha amplification, cyclin-dependent kinase 4 amplification, and cyclin-dependent kinase inhibitor 2A (CDKN2A) homozygous deletion were clearly distinguished from those with normal copy numbers. Moreover, EGFR variant III was accurately detected based on CNA.

Conclusions

Thus, our results demonstrate that copy number analysis can be successfully performed by MLPA of cfDNA extracted from the CSF of patients with diffuse glioma.

Unusual imaging characteristics of cystic meningioma in cerebellopontine angle

We report a case of cystic meningioma at the left cerebellopontine angle (CPA). Magnetic resonance imaging demonstrated both solid and cystic components in the tumor. The cystic component appeared slightly hyperintense compared to cerebrospinal fluid on fluid-attenuated inversion recovery (FLAIR) imaging. A hypointense tubular structure was identified in the cystic component on 3D driven equilibrium sequencing. These imaging findings are unusual for cystic meningioma. However, awareness of these unusual imaging features is important to determine appropriate treatment strategies although cystic meningioma at the CPA is extremely rare.

Discrepancy in the Ki67 labeling index of brain and orbital metastatic lesions from gastrointestinal neuroendocrine tumors: A case report

Proliferative activity examined by Ki67 labeling index (LI) plays pivotal role for managing gastrointestinal neuroendocrine tumor (GI-NET). Few reports indicated the intra-patient heterogeneity of Ki67-LI among metastatic tumor sites. We report a case of brain and orbital metastases from GI-NET that showed discrepancy of the Ki67-LI. A 71 year-old woman who was diagnosed as GI-NET with liver and bone metastases and performed medical therapy, had headache, right exophthalmos, and pain of right eye and was referred to our department. Magnetic resonance image revealed that tumors in the left occipital region and right orbit. We diagnosed as metastatic brain and orbital tumors from GI-NET. Surgical removal of both symptomatic lesions was performed and the diagnosis was pathologically confirmed. Immunohistochemical studies revealed the discrepancy of the Ki67-LI of the lesions (brain tumor: 8% versus orbital tumor: 22%). Sampling of multiple metastatic sites may prevent underestimate tumor proliferative activity.

Five-Year Changes in Cognitive Function and Their Predictor in Adult Moyamoya Disease

OBJECTIVE

The long-term outcomes of cognitive function in moyamoya disease remain unknown. We aimed to assess 5-year changes in cognitive function in adult moyamoya disease patients and to evaluate the value of the magnetic resonance angiography (MRA) steno-occlusive score to predict cognitive changes.

METHODS

Participants comprised 20 consecutive patients whose cognitive functions had been evaluated using the Frontal Assessment Battery (FAB) and Neurobehavioral Cognitive Status Examination (Cognistat) at baseline and reassessed 5 years later.

RESULTS

The total FAB score and total Cognistat score were lower after 5 years in 9 patients each. The Wilcoxon signed-rank test showed that subscores for conceptualization and comprehension increased, while subscores for mental flexibility, programming, and inhibitory control significantly decreased after 5 years. The right MRA total score and right posterior cerebral artery score were negatively associated with 5-year changes in the total FAB score and total Cognistat score. The right posterior cerebral artery score was significantly associated with changes in subscores for mental flexibility, programming, sensitivity to interference, and construction.

CONCLUSIONS

Specific cognitive domains can decline over time in patients with adult moyamoya disease. MRA findings might be useful for predicting future declines in cognitive function.

Microsurgical Resection of Tuberculum Sellae Meningioma through Pterional Approach with Extradural Optic Canal Unroofing

Tuberculum sellae meningiomas pose significant challenges because they are surrounded by crucial neurovascular structures, such as the optic and oculomotor nerves, pituitary stalk, internal carotid artery and its branches, and the anterior cerebral arteries. Even if small, such meningiomas frequently extend to the optic canal that is considered a poor prognostic factor for vision. In this video clip, we illustrate the case of a 60-year-old female who had an approximately 3-cm tuberculum sellae meningioma with optic canal involvement. She underwent surgical resection of the tumor through a pterional approach. After extradural optic canal unroofing, detaching, devascularizing, and debulking the tumor, careful dissection of the meningioma from the surrounding tissues was performed. Next, the tumor extensions into both of the optic canals were removed. Finally, coagulation and resection of the tumor origin on the dura of the tuberculum sellae following Simpson's grade-I resection were performed. Histopathology revealed that the tumor was a World Health Organization (WHO) grade-I meningioma. The patient had an uneventful postoperative course and her visual acuity was preserved, with no visual field defect on postoperative visual examination. In this video, the basic surgical techniques in performing extradural optic canal unroofing, preserving the arachnoid plane, and stay in collect layer, which is the essential technique for dissecting meningiomas and for preserving neurovascular structures, are demonstrated.

The link to the video can be found at: https://youtu.be/vD54Iji0C4Q.

Ankle-Brachial Index and Cardio-Ankle Vascular Index as Predictors of Cognitive Decline Over Time After Carotid Endarterectomy

Objective: Patients with carotid stenosis risk cognitive impairment even after carotid endarterectomy (CEA) because of the long-term presence of vascular risk factors. Early prediction of cognitive decline is useful because early appropriate training for impaired cognitive domains can improve their functions. Ankle-brachial index (ABI) and cardio-ankle vascular index (CAVI) are frequently used as general indicators of systemic atherosclerosis and are associated with cognitive function in the general population. This study aimed to evaluate the utility of those vascular biomarkers for predicting cognitive decline in patients after CEA.

Methods: Patients who had undergone both CEA at our institute and cognitive evaluations between March 2016 and January 2022 were invited to participate in this study. Associations between ABI or CAVI three years before baseline and cognitive function at baseline were assessed retrospectively in 94 patients, and associations between ABI or CAVI at baseline and three-year changes in cognitive functions were assessed prospectively in 24 patients. Cognitive functions were assessed using the Frontal Assessment Battery (FAB) and Neurobehavioral Cognitive Status Examination (Cognistat).

Results: Low ABI three years before baseline was associated with poor performances on Cognistat and FAB at baseline. ABI, as a continuous measure, three years before baseline, showed positive linear associations with total Cognistat score and subscores for naming, construction, and judgment at baseline. The Wilcoxon signed-rank test showed that the total Cognistat score, total FAB score, and subscores for attention and inhibitory control declined after three years. CAVI at baseline was negatively associated with three-year changes in total Cognistat score and subscores for naming, construction, and memory.

Conclusion: Cognitive function can decline over time in patients with carotid stenosis even after CEA. ABI and CAVI might be useful to predict cognitive function and its decline among patients who have undergone CEA.

Preoperative Prediction of Intracranial Meningioma Grade Using Conventional CT and MRI

Objective

Preoperative diagnosis of tumor grade can assist in treatment-related decision-making for patients with intracranial meningioma. This study aimed to distinguish between high-grade and low-grade meningiomas using conventional CT and MRI.

Methodology

We retrospectively analyzed 173 consecutive patients with intracranial meningioma (149 low-grade and 24 high-grade tumors) who were treated surgically at the National Hospital Organization Kyushu Medical Center from 2008 to 2020. Clinical and radiological features, including tumor doubling time (Td) and relative growth rate (RGR), were compared between low-grade and high-grade meningiomas.

Results

Multivariate logistic regression analysis showed that symptomatic tumor (p=0.001), non-skull base location (p=0.006), irregular tumor shape (p=0.043), tumor heterogeneity (p=0.025), and peritumoral brain edema (p=0.003) were independent predictors of high-grade meningioma. In 53 patients who underwent surgery because of tumor progression, progression to symptoms (p=0.027), intratumoral heterogeneity (p<0.001), peritumoral brain edema (p=0.001), larger tumor volume (p=0.005), shorter Td (p<0.001), and higher RGR (P<0.001) were significantly associated with high-grade meningioma. Receiver operating characteristics (ROC) curve analysis showed that the optimal Td and annual RGR cut-off values to distinguish high-grade from low-grade meningioma were 460.5 days and 73.2%, respectively (100% sensitivity and 78.6% specificity).

Conclusion

Based on our findings, conventional CT and MRI are useful methods to predict meningioma grades before surgery. High-grade lesions are associated with non-skull base location, irregular tumor shape, intratumoral heterogeneity, and peritumoral brain edema. High-grade meningioma should be suspected in tumors that exhibit Td <460.5 days or annual RGR >73.2% or those that develop intratumoral heterogeneity or surrounding brain edema on surveillance imaging.

Efficacy of endoscopic treatment for chronic subdural hematoma surgery

Endoscopic treatment is a potential therapeutic addition to chronic subdural hematoma (CSDH) surgery. However, the effect of endoscopic treatment remains controversial. Herein, we examined the optimal indication for endoscopic treatment in CSDH surgery. We retrospectively analyzed 380 consecutive patients with CSDH who underwent single burr-hole craniostomy. We defined postoperative rebleeding as radiological re-accumulation or increased computed tomography value of the hematoma. Reoperation was performed following further hematoma accumulation and/or neurological deterioration. Complicated CSDH was radiologically defined as a hematoma with a clot and/or fibrous septum. There were no differences in baseline characteristics or postoperative mortality and morbidity between the endoscope (97 patients) and control (283 patients) groups. The incidence of postoperative rebleeding (9.3% vs 25.1%, respectively; P = 0.001) and reoperation (0% vs 9.2%, respectively; P = 0.004) were significantly lower in the endoscope group versus controls. Multivariate analysis showed that males (odds ratio 2.14, 95% confidence interval 1.19-3.81; P = 0.012) and endoscopy (odds ratio 0.29, 95% confidence interval 0.13-0.59; P = 0.001) were independently associated with postoperative rebleeding. When CSDHs were divided into two types based on hematoma component, 175 patients exhibited complicated CSDH. There was a significant reduction in postoperative rebleeding (6.5% vs 23.0%, respectively; P = 0.010) and reoperation (0% vs 9.7%, respectively; P = 0.027) in complicated CSDH patients. Endoscopic treatment in CSDH surgery does not increase the risk of surgical complications. Complicated CSDH with a clot and/or septum may be an optimal indication for endoscopic treatment in CSDH surgery to reduce postoperative recurrence.

Microsurgical Anatomy of the Inferior Petroclival Vein and its Relation to Surrounding Structures: A Cadaveric and Radiological Study

BACKGROUND

The inferior petroclival vein (IPV) courses along the extracranial surface of the petroclival fissure. It is occasionally involved in vascular diseases and has recently been used for vascular access to the cavernous sinus. However, detailed descriptions of its anatomy are currently lacking.

OBJECTIVE

To define the anatomic relationship between the IPV and its surrounding structures based on cadaveric dissection and radiological analysis.

METHODS

A dry skull and an injected cadaver head were examined to reveal the relationships between the IPV and its surrounding structures. The existence of the IPV and its relationships with other venous structures were also examined by contrast-enhanced, fat-suppressed T1-weighted magnetic resonance imaging in 26 patients (51 sides).

RESULTS

The entire course of the IPV was shown via stepwise cadaver dissection from below. Its relationships with surrounding structures, such as the jugular bulb, sigmoid sinus, inferior petrosal sinus, petrosal venous confluence, and the posterior, lateral, and anterior condylar veins, were also shown. In the radiological analysis, the IPV was identified on all sides. The rostral end of the vein was connected to the venous plexus around the carotid artery on all sides. The vein drained into the caudal end of the inferior petrosal sinus (49/51 sides, 96.1%) or into the anterior condylar vein (2/51 sides, 3.9%).

CONCLUSION

A precise understanding of the anatomy of the IPV will enable endovascular and skull base surgeons to achieve diagnoses and gain safe access to lesions involving the IPV.

Discrepancy in the Ki67 labeling index of brain and orbital metastatic lesions from gastrointestinal neuroendocrine tumors: A case report

Proliferative activity examined by Ki67 labeling index (LI) plays pivotal role for managing gastrointestinal neuroendocrine tumor (GI-NET). Few reports indicated the intra-patient heterogeneity of Ki67-LI among metastatic tumor sites. We report a case of brain and orbital metastases from GI-NET that showed discrepancy of the Ki67-LI. A 71 year-old woman who was diagnosed as GI-NET with liver and bone metastases and performed medical therapy, had headache, right exophthalmos, and pain of right eye and was referred to our department. Magnetic resonance image revealed that tumors in the left occipital region and right orbit. We diagnosed as metastatic brain and orbital tumors from GI-NET. Surgical removal of both symptomatic lesions was performed and the diagnosis was pathologically confirmed. Immunohistochemical studies revealed the discrepancy of the Ki67-LI of the lesions (brain tumor: 8% versus orbital tumor: 22%). Sampling of multiple metastatic sites may prevent underestimate tumor proliferative activity.

Neuroimaging Recommendations in Outpatients With Dementia: Three Cases of Frontal Meningioma Demonstrating Reversible Dementia

Benign brain tumors largely affect the brain and can lead to reversible dementia, which can be resolved following the treatment of the primary etiology. Herein, we report three cases of relatively large frontal meningiomas in patients who presented with cognitive impairment as initial symptoms. The three participants demonstrated notable dementia alongside frontal meningioma. Following resection, all patients showed dramatic cognitive function improvement, and they successfully returned to society. Our cases illustrate the benefit of active surveillance with neuroimaging in selected patients, especially those who present with acute or subacute dementia.

Carotid ultrasonography predicts collateral development following combined direct and indirect revascularization surgery in adult ischemic Moyamoya disease

OBJECTIVE

The relationship between carotid ultrasonographic parameters and postoperative collateral development in adult ischemic moyamoya disease (MMD) patients who received combined direct and indirect revascularization surgery remains unclear. Herein, we investigated the postoperative changes in carotid ultrasonographic parameters in patients with adult ischemic MMD.

METHODS

We studied 28 adult ischemic MMD patients (31 hemispheres) who underwent combined revascularization surgery. Patients underwent preoperative and postoperative (within 14 days and 3, 12, and 24 months after surgery) magnetic resonance imaging and carotid ultrasonography. We defined the hemisphere in which all signal intensities of the superficial temporal, middle meningeal, and deep temporal arteries were increased compared with that before surgery on magnetic resonance angiography as well-developed collateral establishment.

RESULTS

Patients with good collateral establishment on MRA at 2-year after surgery had a lower external carotid artery (ECA) pulsatility index (PI) (P = 0.0413) and ECA/internal carotid artery (ICA) pulsatility index (PI) ratio (P = 0.0427) at 3-month post-operation. At 3-month post-operation, a cut-off ECA PI of 1.416 (sensitivity 40.0 %, specificity 92.3 %, area under the curve 0.7282, likelihood ratio 5.20, P = 0.0404) and ECA/ICA PI ratio of 0.8768 (sensitivity 50.0 %, specificity 92.31 %, area under the curve 0.7308, likelihood ratio 6.50, P = 0.0415) provided reliable values for good prediction of collateral development at 2 years after revascularization.

CONCLUSION

ECA/ICA PI ratio and ECA PI at 3-month after surgery can be one of the indicators for predicting future well-developed neovascularization on MRA and better outcome in patients with adult ischemic MMD who received combined direct and indirect revascularization surgery.

[Unruptured Fronto-Orbital Artery Aneurysm Anomalously Originating from the Proximal Segment of the Anterior Cerebral Artery(A1)Concurrent with Tuberculum Sellae Meningioma:A Case Report]

We report a case of an unruptured aneurysm arising from the bifurcation of the fronto-orbital artery originating from the proximal segment of the left anterior cerebral artery(A1)concurrent with a tuberculum sellae meningioma. A 46-year-old woman presented with a right visual disturbance and left temporal hemianopsia. Preoperative neuroradiological examination showed a heterogeneously enhanced extra-axial suprasellar tumor expanding to the right optic canal and 3-mm diameter aneurysm arising from the bifurcation of the fronto-orbital artery originating from the proximal segment of the left anterior cerebral artery(A1). She underwent total removal of the tumor and neck clipping of the aneurysm via a right pterional approach without any additional deficits. Postoperative MRI and 3D CTA showed total tumor removal and complete obliteration of the aneurysm. The patient was discharged 21 days after surgery without new or worsened postoperative neurological deficits. Cerebral aneurysm concurrent with meningioma is extremely rare. Preoperative diagnosis and appropriate assessment of both the meningioma and unruptured aneurysm are warranted to prevent severe complications.

Common carotid flow velocity is associated with cognitive function after carotid endarterectomy

The relationship between ultrasonographic flow parameters and cognitive function has not been well studied. This study aimed to clarify associations between carotid flow velocity (FV) and cognitive function in patients with a history of carotid endarterectomy (CEA). Ninety-four patients who previously underwent CEA participated in this study. The Neurobehavioral Cognitive Status Examination (Cognistat) and Frontal Assessment Battery (FAB) were adopted to assess cognitive functions at a mean of 6.5 ± 3.2 years after CEA. End-diastolic flow velocity (EDV) of the left and right common carotid artery (CCA) was significantly associated with total Cognistat score (p < 0.001) and total FAB score (p < 0.05). Pulsatility index (PI) of the left CCA was significantly associated with total Cognistat score and total FAB score (p < 0.01). A cut-off right CCA EDV of 14.5 cm/s offered the most reliable predictor of the bottom 25th percentile of total Cognistat score (sensitivity 83.3%, specificity 61.0%, area under the curve (AUC) 0.731, p = 0.0060), while a cut-off left CCA PI of 1.83 was the most reliable predictor of the bottom 25th percentile of total FAB score (sensitivity 73.3%, specificity 60.0%, AUC 0.679, p = 0.0179). Left and right CCA EDV correlated with sub-components of comprehension, construction, judgment, programming (p < 0.01), and conceptualization (p < 0.05). Right CCA EDV correlated with similarity (p < 0.01), repetition, naming, and memory (p < 0.05). Left CCA PI correlated with attention, conceptualization (p < 0.01), repetition, construction, similarity, and mental flexibility (p < 0.05), while right CCA PI correlated with construction (p < 0.05). CCA FV may offer useful markers of cognitive functions in patients with a history of CEA.

Impact of antithrombotic therapy on surgical treatment in patients with chronic subdural hematoma

OBJECTIVE

The effects of antithrombotic therapy on chronic subdural hematoma (CSDH) are controversial. Herein, we investigated the association of antithrombotic therapy with surgical complications and outcomes in patients with CSDH.

METHODS

We retrospectively analyzed 323 consecutive patients with CSDH who underwent single burr-hole craniostomy.

RESULTS

One hundred and eight patients (33%) underwent preoperative antithrombotic therapy. Hemorrhagic and thromboembolic complications were detected in 6 and 8 patients, respectively, which peaked at 3 and 4.5 days after CSDH surgery, respectively. CSDH recurrence was detected in 62 cases, and reoperation was required in 16 cases. Discontinuance of antiplatelet therapy for >2 weeks was significantly associated with thromboembolic complications (43%; p = 0.005). Postoperative use of multiple antithrombotic agents was significantly associated with CSDH recurrence (40%; p = 0.03). Further, earlier recurrence within 2 weeks was significantly associated with the following reoperation (62%; p = 0.006).

CONCLUSIONS

To reduce morbidity and minimize the risk of CSDH reoperation, the optimal timing for resumption of antithrombotic agents is approximately 3 days after CSDH surgery. Postoperative use of multiple antithrombotic agents can increase CSDH recurrence, while earlier recurrence may be a predictor for the following reoperation.

eGFR and deep white matter hyperintensity as predictors of cognitive decline long after carotid endarterectomy

Chronic kidney disease and white matter hyperintensity (WMH) are associated with cognitive decline. The aim of this study was to assess the correlations between estimated glomerular filtration rate (eGFR) or WMH and cognitive function in patients who have undergone carotid endarterectomy (CEA). Cognitive functions were investigated using the Neurobehavioral Cognitive Status Examination (Cognistat) in 83 patients who had undergone CEA. The eGFR at 5 years prior to examination was significantly associated with severe cognitive impairment (odds ratio, 0.89 per 1-mL/min/1.73 m² increase, 95% confidence interval 0.82–0.97, p = 0.0004). Receiver operating characteristic analysis revealed that a cutoff eGFR of 46.8 mL/min/1.73 m² at 5 years prior to examination offered the most reliable predictor of severe cognitive impairment (sensitivity 88.9%, specificity 76.5%, area under the curve 0.848). The eGFR at 5 years prior to examination showed a significant linear association with total Cognistat score (r² = 0.11035, p = 0.0032) compared to eGFR at 3 years prior to examination (r² = 0.06455, p = 0.0230) or at examination (r² = 0.0210, p = 0.0210). Spearman’s correlation coefficient revealed that orientation, comprehension, repetition, construction, memory, and similarity correlated with eGFR at 5 years prior to examination. Conversely, Fazekas grade for deep WMH at examination was associated with total Cognistat score (p = 0.0016), unlike that at 3 years (p = 0.0100) or 5 years prior to examination (p = 0.0172). While eGFR correlates with future cognitive function, deep WMH associates with present cognitive function in patients who have undergone CEA.

Single loop interrupted suture technique for cerebrovascular anastomosis: Technical note

The ideal suturing technique for cerebrovascular anastomosis remains a point of debate. Although simple interrupted sutures are considered to achieve higher patency, they require longer anastomosis time compared with running sutures. The authors describe a novel techniques named single loop interrupted suture to place interrupted sutures for cerebrovascular anastomosis. The single loop interrupted suture technique consists of repeatedly placing, tying and cutting a single loop between anchor stitches. A single loose loop was placed next to the anchor stitch, tied and cut, and then another loop was placed next to the knot. The loops resulted in efficiently placed interrupted sutures. This technique is employed for a range of end-to-side cerebrovascular anastomosis procedures, and is feasible in placing interrupted suture.

Three-Piece Orbitozygomatic Craniotomy: Anatomical and Clinical Findings

OBJECTIVE

To describe the technical details of 3-piece orbitozygomatic (OZ) craniotomy using a diamond threadwire saw as an alternative to cutting the orbital rim and zygoma.

METHODS

The details of this procedure are presented by cadaver dissection and a surgical case.

RESULTS

Three-piece OZ craniotomy consists of 3 steps of bone flap elevation. First, the zygomatic arch is divided and reflected downward with the temporal muscle. This provides adequate exposure around the inferior orbital fissure with less skin flap retraction. In the second step, frontotemporal craniotomy is performed close to the skull base without the requirement for additional craniectomy. Finally, the superolateral wall of the orbital bone flap is elevated. Cutting the orbital rim and zygoma with a diamond threadwire saw allows reconstruction with a minimal bone gap.

CONCLUSIONS

The herein-described 3-piece OZ craniotomy technique is simple and provides excellent brain exposure equivalent to that achieved by 1- and 2-piece OZ craniotomy while minimizing flap retraction and requiring less additional bone removal.

A case of metastatic brain tumor mimicking an expanding thalamic hematoma

Background:

Brain tumor are a major etiology of secondary intracranial hemorrhage (ICH) because ICH in patients with cancer often occurs from an intratumoral hemorrhage. However, it is sometimes difficult to detect a tumor when it is tiny and buried, especially during initial examination.

Case Description:

A 65-year-old woman who was diagnosed with pulmonary small cell carcinoma 6 months previously developed sudden-onset consciousness disturbance and left hemiparesis. Head computed tomography (CT) showed a round, high-density lesion with a diameter of 31 mm in the right thalamus. There was no enhancement with administration of contrast agent. Five days later, CT revealed significant progression of the hematoma in the thalamus with perifocal edema. She underwent total removal of the hematoma. Histopathological examination revealed a tiny cluster of metastatic cancer tissue within the hematoma.

Conclusions:

When cerebral hemorrhage occurs in a cancer patient, we must consider the possibility of hemorrhage due to a brain metastasis.

Abducens Nerve Schwannoma: A Case Report and Literature Review

BACKGROUND

Abducens nerve function seldom shows complete recovery after removal of abducens nerve schwannoma. No cases with unclear course of the abducens nerve during surgery have been reported to achieve complete recovery of nerve function.

CASE DESCRIPTION

We report the case of a 44-year-old woman who presented with occasional dysgeusia without abducens nerve paresis. Magnetic resonance imaging showed a solid tumor about 2 cm in diameter at the left cerebellopontine cistern. Cranial nerves except the abducens nerve appeared intact. The tumor was removed via suboccipital craniotomy. The abducens nerve was totally invisible on the surface of the tumor throughout the procedure. Only short segments of abducens nerve were identifiable at around Dorello's canal and the root exit zone. The tumor was resected by subcapsular dissection, and part of the tumor capsule was preserved as a scaffold for nerve generation, although whether any abducens nerve was included remained uncertain. Histopathologic examination confirmed World Health Organization grade I schwannoma. Postoperatively, the patient presented with complete left abducens nerve paresis and diplopia, but abducens nerve function began to improve 3 months later and had completely recovered within 16 months after surgery.

CONCLUSIONS

This represents the first description of abducens nerve schwannoma in which the course of the abducens nerve was intraoperatively unclear but complete recovery was achieved. In such cases, intentional subcapsular dissection may potentiate functional recovery.

Ruptured cerebral arteriovenous malformation during fifth pregnancy: A case report and literature review

BACKGROUND

Whether the risk of rupture of a cerebral arteriovenous malformation (AVM) increases during pregnancy remains controversial. Moreover, it is unclear whether the number of pregnancies correlates with AVM rupture risk. We report a case of ruptured AVM during the fifth pregnancy.

CASE DESCRIPTION

A 34-year-old woman presenting sudden headache and vomiting was admitted to our hospital. Neuroimaging revealed a subarachnoid hemorrhage due to a ruptured AVM in the right temporal lobe. She was pregnant (9 weeks and 1 day), and she had previously experienced four normal vaginal deliveries (gravidity and parity G₄P₄) without complications. Elective treatment including neuroendovascular and direct surgery was performed, and the AVM was safely resected (at 15 weeks 6 days of pregnancy). She underwent elective caesarean section without complications 151 days following the AVM resection (at 37 weeks 1 day of pregnancy), and the baby was healthy.

CONCLUSIONS

This report suggests that the risk of AVM rupture persists even after multiple deliveries. Intracranial hemorrhage should be suspected even in pregnant patients who underwent multiple deliveries, and a rapid diagnosis and appropriate treatment are necessary.

Multiple Brain Metastases from Pancreatic Adenocarcinoma Manifesting with Simultaneous Intratumoral Hemorrhages

BACKGROUND

Pancreatic adenocarcinoma rarely metastasizes to the brain, and clinical features of brain metastasis in such cases remain elusive. To the best of our knowledge, only 21 cases of brain metastasis from pancreatic adenocarcinoma have been previously reported in the English language literature.

CASE DESCRIPTION

A 61-year-old woman was diagnosed with pancreatic adenocarcinoma and began chemotherapy 1 year 4 months before the current admission. Three days before the current admission, she developed acute dysarthria. She was referred to a cancer center, where neuroradiologic examination showed multiple metastatic brain tumors, including a 30-mm-diameter tumor in the right cerebellar region. She was transferred to our institute. Three days after admission, she developed sudden-onset disturbance of consciousness and left hemiparesis. Computed tomography and magnetic resonance imaging of the head showed that the metastatic lesions had increased in size with development of intratumoral hemorrhage and obstructive hydrocephalus. She underwent urgent removal of the tumor in the cerebellum. Obstructive hydrocephalus was relieved, and her consciousness improved immediately after surgery. She was transferred to the palliative care unit of the cancer center and died under hospice care 3 weeks after surgery.

CONCLUSIONS

This case demonstrates that brain metastases from pancreatic adenocarcinoma can enlarge suddenly and simultaneously with intratumoral hemorrhage even without coagulation disorders, resulting in neurologic deterioration in a short time. Surgical resection of metastatic brain lesions from pancreatic adenocarcinoma has an extremely limited role, but such treatment can remove neurologic symptoms and temporarily improve the patient's quality of life in selected cases.

Long-Term Neurocognitive Outcomes in Patients with Adult Moyamoya Disease

OBJECTIVE

Neurocognitive impairment is a frequent complication of moyamoya disease in adults, but the long-term outcomes of neurocognitive function remain unclear. We evaluated neurocognitive functions in a group of patients with a history of moyamoya disease and assessed the relationship between regional cerebral blood flow (rCBF) and neurocognitive functions.

METHODS

We studied 53 patients with a history of adult moyamoya disease. Neurocognitive functions were evaluated with the Neurobehavioral Cognitive Status Examination (Cognistat) and the Frontal Assessment Battery. The relationship between rCBF and neurocognitive functions were assessed in patients for whom rCBF was measured using single-photon emission computed tomography with ¹²³I-iodoamphetamine.

RESULTS

Patients had a history of moyamoya disease for an average of 10.6 years, with 23 patients managed conservatively and 30 managed using revascularization. Attention, memory, conceptualization, mental flexibility, and inhibitory control were impaired but with no significant difference between conservatively and surgically treated patients. Posterior cerebral artery involvement and frontal lobe infarction were not associated with neurocognitive examination scores in nonrevascularized or revascularized patients. Orientation, comprehension, calculation, conceptualization, and sensitivity to interference correlated with rCBF in the left ventral middle cerebral artery territory (P < 0.01), whereas memory correlated with rCBF in the right dorsal anterior cerebral artery territory (P < 0.01). Conceptualization also correlated with rCBF in the left dorsal anterior cerebral artery territory (P < 0.001).

CONCLUSIONS

Our findings indicate that long-standing hypoperfusion in specific brain regions can cause related neurocognitive dysfunction even in mild moyamoya disease managed conservatively.

Surgical outcome in elderly patients with intracranial meningioma

The aim of this study was to examine the utility of surgical management of intracranial meningioma in elderly patients. A total of 138 patients with intracranial meningiomas who underwent surgery from 2008 to 2017 were divided into elderly (≥75 years old, n = 34) and younger (<75 years old, n = 104) groups. Clinical and radiological data were retrospectively analyzed. Total tumor removal was achieved in 79% of elderly patients, which was similar to that in young patients (85%, p = .81). The average preoperative Karnofsky performance scale score in elderly patients was significantly lower than that in young patients (70.6 vs. 90.4, respectively; p < .0001). However, the average change in the Karnofsky performance scale score after surgery was similar between the two groups (0.3 vs. -0.4, respectively; p = .36). Histopathological grading revealed that the incidence of malignant meningioma (World Health Organization grades II and III) was significantly higher in elderly patients than that in young patients (44% vs. 14%, respectively; p = .004). Among meningiomas showing chronological progression, World Health Organization grade II and III meningiomas accounted for 67% of tumors in elderly patients, but only 23% in younger patients (p = .01). These data suggest that surgical removal of meningiomas may be a safe and useful treatment strategy in elderly patients.

Inhibition of glioblastoma cell invasion by hsa-miR-145-5p and hsa-miR-31-5p co-overexpression in human mesenchymal stem cells

OBJECTIVE

Human bone marrow–derived mesenchymal stem cells (hMSCs) show tropism for brain tumors and may be a useful vehicle for drug or gene delivery to malignant gliomas. Recently, some microRNAs (miRNAs) have been shown to suppress the invasiveness of malignant gliomas.

METHODS

To test their potential to become vehicles for the delivery of miRNA to malignant gliomas, hMSCs were engineered so that hMSC secretion of miRNAs that inhibit glioma cell invasion was enabled without altering the hMSC tropism for glioma cells.

RESULTS

In coculture, hMSCs cotransfected with hsa-miR-145-5p and -31-5p miRNAs showed markedly reduced invasion by U87 glioma cells in a contact-dependent manner both in vitro and ex vivo, with invasion of hMSCs cotransfected with these 2 miRNAs by the U87 cells reduced to 60.7% compared with control cells. According to a Matrigel invasion assay, the tropism of the hMSCs for U87 cells was not affected. In glioma cell lines U251 and LN229, hMSCs exhibited tropism in vivo, and invasion of hMSCs cotransfected with hsa-miR-145-5p and -31-5p was also significantly less than that of control cells. When U87 cells were coimplanted into the striatum of organotypic rat brain slices with hMSCs cotransfected with hsa-miR-145 and -31-5p, the relative invasive area decreased by 37.1%; interestingly, these U87 cells showed a change to a rounded morphology that was apparent at the invasion front. Whole-genome microarray analysis of the expression levels of 58,341 genes revealed that the co-overexpression of hsa-miR-145-5p and -31-5p downregulated FSCN1 expression in U87 cells.

CONCLUSIONS

This study demonstrates that miRNA overexpression in hMSCs can alter the function of glioma cells via contact-dependent transfer. Co-overexpression of multiple miRNAs may be a useful and novel therapeutic strategy. The study results suggest that hMSCs can be applied as a delivery vehicle for miRNAs.

Altered Expression of MicroRNA-15a and Kruppel-Like Factor 4 in Cerebrospinal Fluid and Plasma After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Cerebral vasospasm (CVS) is a major determinant of prognosis in patients with subarachnoid hemorrhage (SAH). Alteration in the vascular phenotype contributes to development of CVS. However, little is known about the role of microRNAs (miRNAs) in the phenotypic alteration after SAH. We investigated the expression profile of miRNAs and the chronologic changes in the expression of microRNA-15a (miR-15a) and Kruppel-like factor 4 (KLF4), a potent regulator of vascular phenotype modulation that modulates the expression of miR-15a, in the plasma and cerebrospinal fluid (CSF) of patients with SAH.

METHODS

Peripheral blood and CSF samples were collected from 8 patients with aneurysmal SAH treated with endovascular obliteration. Samples obtained from 3 patients without SAH were used as controls in the analysis. Exosomal miRNAs were isolated and subjected to microarray analysis with the three-dimensional-gene miRNA microarray kit. The time course of the expression of miR-15a and KLF4 was analyzed using quantitative real-time polymerase chain reaction.

RESULTS

Microarray analysis showed that 12 miRNAs including miR-15a were upregulated or downregulated both in the CSF and in plasma after SAH within 3 days. Quantitative real-time polymerase chain reaction showed that miR-15a expression was significantly increased in both the CSF and plasma, with a peak around 3-5 days after SAH, whereas the expression of KLF4 was significantly decreased around 1-3 days after SAH and remained lower than in controls.

CONCLUSIONS

Our results suggest that an early and persistent decrease in KLF4 followed by an increase in miR-15a may contribute to the altered vascular phenotype, resulting in development of CVS.

Impact of antithrombotic treatment on clinical outcomes after craniotomy for unruptured intracranial aneurysm

OBJECTIVE

Patients receiving antithrombotic treatment occasionally undergo craniotomy. We aimed to explore the impact of perioperative use of antithrombotic agents on the occurrence of surgical complications and clinical outcomes in patients with unruptured intracranial aneurysm (UIA).

PATIENTS AND METHODS

We retrospectively analyzed 401 consecutive patients who had undergone craniotomy for UIA at our institution between January 2006 and December 2016. Patients were divided into two groups: those who received oral antiplatelet and/or anticoagulant agents during the perioperative period (antithrombotic treatment group, n=45); and those who did not (no antithrombotic treatment group, n=356). In the antithrombotic treatment group, 40 patients received antiplatelet alone, 2 received anticoagulant alone, and 3 received antiplatelet plus anticoagulant.

RESULTS

The two groups showed no significant differences in mortality, morbidity, or occurrence of symptomatic brain infarction, but intracranial hemorrhage was more frequent in the antithrombotic treatment group than in the no antithrombotic treatment group (p=0.0187). Multivariate analysis revealed posterior location of the aneurysm (odds ratio (OR), 8.10; 95% confidence interval (CI), 2.77-23.68; p=0.0001) and surgical procedure (OR, 5.48; 95%CI, 1.68-17.86; p=0.0048) as significantly correlated with severe morbidity, and intracranial hemorrhage as correlated significantly with antithrombotic treatment (OR, 3.83; 95%CI, 1.36-10.76; p=0.0110).

CONCLUSIONS

This study provides important information about the occurrence of intracranial hemorrhage and clinical outcomes in patients undergoing antithrombotic treatment during the perioperative period of craniotomy for UIA.

Detection of proneural/mesenchymal marker expression in glioblastoma: temporospatial dynamics and association with chromatin-modifying gene expression

Proneural and mesenchymal are two subtypes of glioblastoma identified by gene expression profiling. In this study, the primary aim was to detect markers to develop a clinically applicable method for distinguishing proneural and mesenchymal glioblastoma. The secondary aims were to investigate the temporospatial dynamics of these markers and to explore the association between these markers and the expression of chromatin-modifying genes. One hundred thirty-three glioma samples (grade II: 14 samples, grade III: 18, grade IV: 101) were analyzed. We quantified the expression of 6 signature genes associated with proneural and mesenchymal glioblastoma by quantitative reverse transcription-polymerase chain reaction. We assigned proneural (PN) and mesenchymal (MES) scores based on the average of the 6 markers and calculated a predominant metagene (P-M) score by subtracting the MES from the PN score. We used these scores to analyze correlations with malignant transformation, tumor recurrence, tumor heterogeneity, chromatin-modifying gene expression, and HDAC7 expression. The MES score positively correlated with tumor grade, whereas the PN score did not. The P-M score was able to distinguish the proneural and mesenchymal subtypes. It was decreased in cases of tumor recurrence and malignant transformation and showed variability within a tumor, suggesting intratumoral heterogeneity. The PN score correlated with the expression of multiple histone-modifying genes, whereas the MES score was associated only with HDAC7 expression. Thus, we demonstrated a simple and straightforward method of quantifying proneural/mesenchymal markers in glioblastoma. Of note, HDAC7 expression might be a novel therapeutic target in glioblastoma treatment.

Upregulation of tissue inhibitor of metalloproteinase-1 contributes to restoration of the extracellular matrix in the rabbit basilar artery during cerebral vasospasm after subarachnoid hemorrhage

Vascular remodeling caused by extracellular matrix (ECM) metabolism contributes to the development of cerebral vasospasm after subarachnoid hemorrhage (SAH). The balance between tissue inhibitor of metalloproteinases (TIMPs) and matrix metalloproteinases (MMPs) plays an important role in ECM remodeling. We investigated the mechanism of vascular remodeling following cerebral vasospasm in a rabbit double hemorrhage model. Rabbit basilar arteries were harvested on days 3, 5, and 7 after initial hemorrhage. TIMP-1, TIMP-2, MMP-2, and MMP-9 mRNA and protein expression were investigated with microarray analysis, quantitative real-time PCR, immunoblot analysis, and enzyme-linked immunosorbent assay (ELISA). The expression and localization of TIMP-1, TIMP-2, MMP-2, MMP-9, elastin, fibronectin, laminin, and collagens I, III, and IV were investigated with immuohistochemical staining. After SAH, TIMP-1 mRNA and protein expression were significantly increased on day 3 and then decreased to the control level on days 5 and 7. MMP-9 protein expression was significantly increased on day 7. TIMP-2 and MMP-2 mRNA and protein expression were significantly increased on day 7. Elastin, fibronectin, laminin, and collagens I, III, and IV protein expression was decreased on day 3 and then restored to control levels on day 7. Upregulation of TIMP-1 during the early phase of cerebral vasospasm may contribute to the recovery of the ECM during the late phase of cerebral vasospasm, resulting in a protective role of TIMP-1 from cerebral vasospasm. Moreover, the increase in arterial compliance by the decrease in ECM during the early phase of cerebral vasospasm may facilitate vasoconstriction of the cerebral artery.

Abstract T P109: Prediction Of Asymptomatic Cerebrovascular Diseases Before Bypass Surgery For Peripheral Artery Disease

Background & Purpose: Cerebrovascular disease (CVD) and peripheral artery disease (PAD) sometimes coexist with each other. We investigated predictive factors for CVD before bypass surgery for PAD.

Subjects & Methods: For the present study, 200 consecutive PAD patients who were planned to undergo a bypass surgery for their lower extremity artery were included. Before the surgery, all patients were studied by ankle brachial index (ABI), duplex carotid ultrasonography, magnetic resonance imaging (MRI) including diffusion weighted imaging (DWI), and MR angiography. A stenosis of ≥50% or occlusion of the major intracranial or extracranial cerebral arteries was defined as a significant CVD. We also investigated the predictive factors for significant cerebrovascular lesions.

Results: Of the total 200 patients (137 men; 69%, 74±9 years old) studied, a significant CVD of the intracranial or extracranial cerebral arteries was observed in 104 (52%) patients: 57 (29%) in intracranial arteries and 68 (34%) in extracranial arteries. There were asymptomatic ischemic lesions on MRI in 116 (59%) patients. Among them, 13 (7%) patients had asymptomatic high-intense lesions on DWI. In patients with significant CVDs, dyslipidemia (63% vs 47%, p=0.0455), diabetes mellitus (67% vs 37%, p<0.001), prior ischemic stroke (65% vs 48%, p=0.0328), and prior ischemic heart disease (63% vs 46%, p=0.0189) were more frequent, and ABI value was lower (0.34 vs 0.45, p=0.0369) in comparison to patients without CVDs. On ROC curve analysis, the most accurate ABI cut-off value for predicting significant CVDs was 0.46. Prevalence of CVDs tended to increase with the increasing number of risk factors described above (44% in patient with 1, 56% in patient with 2, 71% in patient with 3, 69% in patient with 4, 80% in patient with 5; P<0.0001 for armitage trend). On multivariate analysis, dyslipidemia (OR, 1.93; 95% CI, 1.00-3.81) and diabetes mellitus (OR, 3.06; 95% CI, 1.62-5.86) were independent predictors for significant CVDs.

Conclusions: In PAD patients before the bypass surgery, significant CVDs were observed in 52%. Dyslipidemia and diabetes mellitus were independent predictors for significant CVDs. Number of the predictive factors was also important for predicting CVDs.

Usefulness of three-dimensional T1-weighted spoiled gradient-recalled echo and three-dimensional heavily T2-weighted images in preoperative evaluation of spinal dysraphism

PURPOSE

The aim of this study was to evaluate the usefulness of three-dimensional T1-weighted spoiled gradient-recalled echo (3D T1-GRE) images for the preoperative anatomical evaluation of lumbosacral lipoma, thick filum terminale, and myelomeningocele as a means of compensating for the drawbacks of 3D heavily T2-weighted (3D hT2-W) images.

METHODS

Nine patients with lumbosacral lipomas, one patient with tight filum terminale, and five patients with myelomeningoceles were included in this study. 3D T1-GRE images were compared with 3D hT2-W images or conventional magnetic resonance images in terms of delineation of lipomas and other structures in the patients with lipomas and tight filum terminale. For patients with myelomeningoceles, 3D T1-GRE images were compared with 3D hT2-W images in terms of artifacts in the cerebrospinal fluid (CSF) space.

RESULTS

The 3D T1-GRE images demonstrated lipomas with good contrast to the spinal cord and CSF space and more clearly delineated the anatomical relationship between lipomas and these structures than did the 3D hT2-W images. The 3D T1-GRE images delineated dural defects through which extradural lipomas penetrated into the intradural space. The 3D T1-GRE images also demonstrated the presence or absence of lipomas in the filum terminale and the absence of artifact in the myelomeningoceles. Furthermore, they were useful for differentiating artifacts observed on the 3D hT2-W images from nerve elements.

CONCLUSIONS

The complementary use of 3D T1-GRE and 3D hT2-W images may compensate for the drawbacks of 3D hT2-W images and may eventually improve lesion visualization and surgical decision making.

Long-term hearing outcome after retrosigmoid removal of vestibular schwannoma

Although many investigators have reported the hearing function in the immediate postoperative period in patients with vestibular schwannoma (VS), little is known about the long-term outcomes of the postoperative hearing. The aim of this study was to analyze the long-term hearing outcomes at a mean follow-up of 5 years in patients with unilateral VS treated via the retrosigmoid approach. Twenty-four patients with immediate postoperative serviceable hearing who underwent repeated audiogram or phone interview were included in this study. During the mean follow-up period (68.8 ± 30.2 months, range 14–123 months), serviceable hearing was preserved in 20 out of the 24 patients (83%). Pure tone average (PTA) was reevaluated within 6 months in seven patients. In the two patients whose PTA deteriorated ≥ 5 dB in 6 months after surgery, their PTA worsened ≥ 15 dB compared to the immediate postoperative PTA. In the remaining five patients whose PTA deteriorated < 5 dB in 6 months after surgery, PTA was maintained within a 15-dB deterioration at the final follow-up (p = 0.04, Fisher's exact test). According to Kaplan–Meier survival plots, the 5-year or 7-year preservation rate of serviceable hearing was 86.2% or 71.8%, respectively. Further study will be needed to clarify the mechanism underlying the long-term decline of serviceable hearing; however, the deterioration of PTA in the early postoperative period may help to predict the long-term outcomes of hearing.

Preoperative evaluation and surgical strategies for craniocervical junction dural arteriovenous fistula with multiple feeders: case report and review of the literature

Craniocervical junction dural arteriovenous fistula (CCJDAVF) fed by bilateral vertebral arteries (VAs) is extremely rare. We report a case of a 63-year-old man presenting with progressive myelopathy caused by a CCJDAVF, which was fed by bilateral VAs and occipital and ascending pharyngeal arteries with multiple shunting points and that drained into intracranial sinus and spinal veins. The dural arteriovenous fistula (DAVF) was successfully treated surgically using stepwise indocyanine green (ICG) videoangiography. After surgery, the DAVF disappeared and myelopathy was markedly improved. We show detailed preoperative images and intraoperative findings of this rare DAVF and emphasize the importance of selective angiography for preoperative evaluation of feeding arteries and the usefulness of intraoperative ICG videoangiography for both identification of the fistula and confirmation of its obliteration.

Surgical techniques for the dissection of encased perforators in giant clinoidal meningiomas

BACKGROUND

Surgical treatment of giant clinoidal meningiomas remains a challenging task for neurosurgeons. Here, we present details of the surgical techniques for the dissection of encased perforators.

METHODS

The dissection of encased perforators is summarized as follows: (1) split the tumor above the encased arteries and perforators; (2) find the entrance and exit points of the perforators, and estimate the running course of the perforators within the tumor; (3) dissect and expose the perforators along the estimated line.

CONCLUSIONS

The surgical techniques described in this article will aid in achieving maximum tumor resection while preserving encased perforators.

Facial nerve schwannoma arising from the cerebellopontine angle

A 74-year-old female suffered hearing disturbance in the right ear persisting for several years, followed by sudden onset of right facial nerve palsy. Her symptoms gradually worsened and neuroradiological imaging revealed a 4-cm cerebellopontine angle (CPA) tumor. Intraoperatively, the tumor was found to originate from the facial nerve. Total removal of the tumor was achieved, followed by a split hypoglossal-facial nerve anastomosis. Facial nerve schwannomas are rare and extremely difficult to preoperatively distinguish from vestibular schwannomas, especially if arising from the CPA and the internal auditory canal. However, preoperative diagnosis of facial nerve schwannomas is important because functional preservation of the facial nerve is more challenging than for vestibular schwannomas. Facial nerve palsy is one of the most unique symptoms in patients with facial nerve schwannomas, but is rare with vestibular schwannomas. Facial nerve schwannomas should be included in the differential diagnosis of CPA tumors with atypical clinical manifestations, and patients should be informed before surgery of the possibility of facial nerve dysfunction and the consequent need for facial nerve graft or reconstruction.