Futile recanalization after endovascular treatment in acute ischemic stroke with large ischemic core.

BACKGROUND: Endovascular therapy (EVT) is the treatment of choice for acute ischemic stroke (AIS) with large vessel occlusion. However, in many patients, successful EVT recanalization does not correspond to a clinical improvement, called futile recanalization (FR). We aimed to identify stroke risk factors and patient characteristics associated with FR in AIS with large core infarct (LCI). METHODS: A total of 137 patients with AIS with LCI treated by EVT at a single stroke center were retrospectively included from January 2016 to June 2023. LCI was defined by Diffusion-Weighted Imaging-Alberta Stroke Program Early Computed Tomography Score (DWI-ASPECT) < 6. Patient age, sex, modified Rankin Scale (mRS), National Institutes of Health Stroke Scale (NIHSS), time to treatment, risk factors, and radiologic findings were collected, and potential associations with FR were analyzed. FR was defined as successful reperfusion with modified Thrombolysis in Cerebral Infarction (mTICI) ≥ 2b but without functional independence at 90 days (mRS ≥ 3). A multivariate logistic regression analysis was conducted on the clinical characteristics of patients, based on the presence or absence of FR, and the factors influencing FR. RESULTS: Of 137 patients, 120 showed successful recanalization (mTICI ≥ 2b). All patients were divided into FR (n = 80) and no FR (n = 40) groups. Older age (odds ratio [OR] 1.052, 95% confidence interval [CI] 1.002-1.105; p = 0.041), the higher the initial NIHSS score (OR 1.181, 95% CI 1.037-1.344; p = 0.012), and prior intravenous plasminogen activator (OR 0.310, 95% CI 0.118-0.813, p = 0.017) were independent influencing factors of FR. CONCLUSIONS: The older age, the higher the initial NIHSS, and not receiving intravenous plasminogen activator were independently associated with FR in AIS with LCI. These factors could identify poor responders to EVT recanalization.

Four-dimensional flow MR imaging for evaluating treatment response after transcatheter arterial chemoembolization in cirrhotic patients with hepatocellular carcinoma.

PURPOSE: To prospectively evaluate the potential of four-dimensional (4D) flow magnetic resonance imaging (MRI) in predicting treatment responses after transcatheter arterial chemoembolization (TACE) in cirrhotic patients with hepatocellular carcinoma (HCC). METHODS: A total of 195 patients were classified into four groups (A-D): A, cirrhotic patients without HCC (n = 30); B, cirrhotic patients with HCC before TACE (n = 75); C, cirrhotic patients with HCC showing an incomplete response following TACE (n = 56); and D, cirrhotic patients with HCC achieving a complete response (CR) following TACE (n = 34). The patients were subjected to routine laboratory tests and 4D flow MRI using a 3-T MRI system to measure the quantitative parameters of blood flow in the portal vein (PV), splenic vein (SV), and superior mesenteric vein. The data collected by 4D flow MRI were compared among the groups using one-way analysis of variance. A multivariate analysis was performed to verify the association of clinical characteristics and 4D flow parameters with CR after TACE treatment. RESULTS: The average through-plane velocity, peak velocity magnitude, average net flow, peak flow, and net forward volume in the PV and SV were significantly lower in groups B and C (P < 0.05) compared to those in group A. Moreover, average through-plane velocity and peak velocity magnitude in the PV in groups B and C were significantly lower than those in group D (P < 0.05). The multivariate analysis demonstrated that the average through-plane velocity and peak velocity magnitude in the PV were independently associated with CR in HCC patients after TACE (P < 0.05). CONCLUSION: The quantitative flow data obtained by 4D flow MRI may be useful for predicting CR after TACE in cirrhotic patients with HCC.

Staged operations for a hypervascular mixed germ cell tumor with growing teratoma syndrome: a case report.

INTRODUCTION: A mixed germ cell tumor with a teratoma component can become enlarged following chemotherapy, and such an event is diagnosed as growing teratoma syndrome. Removing large, hypervascular tumors including a tumor encased by developed vasculatures from the pineal region is challenging during a single operation. CASE REPORT: A 15-year-old male underwent chemotherapy for mixed germ cell tumors according to the KSPNO G082 protocol. This case of a mixed germ cell tumor with growing teratoma syndrome was recognized very early during chemotherapy. The tumor was completely removed during the staged operations. First, the anteriorly located tumor on the third ventricle was removed via the transcallosal interforniceal approach, and 1 month later, the occipital transtentorial approach was used for the pineal tumor with decreased vascularity. CONCLUSION: Performing staged operations could be recommended for large hypervascular pineal tumors, which can be safely removed during the second operation once vascularity has decreased.

Multiple craniospinal tumors in a pediatric patient with neurofibromatosis type 2: a case report.

INTRODUCTION: Neurofibromatosis type 2 (NF-2) is an inherited disease, linked with abnormalities in the NF-2 gene, which is located on chromosome 22 and involved in merlin production. Many craniospinal tumors are common in individuals with NF-2. We present a case of NF-2 with the rapid symptomatic progression of multiple craniospinal tumors. CASE REPORT: A 12-year-old male complained of headache and hearing impairment in the right ear for 7 months. Brain magnetic resonance imaging (MRI) revealed a right frontal meningioma, bilateral vestibular and trigeminal schwannomas, and a brainstem tumor. He was diagnosed with NF-2 and underwent brain surgery and radiotherapy for chordoid meningioma. He complained of right leg motor weakness 5 months post-surgery. The spine MRI showed multiple heterogeneously enhanced masses spreading over the entire spinal cord. The symptomatic intradural extramedullary mass at the cervicothoracic area was removed and the histological finding was schwannoma. His leg motor weakness was relieved after surgery. At the 6-month follow-up, brain MRI revealed the progression of the vestibular schwannoma, trigeminal schwannoma, and brainstem tumor. The patient was treated with bevacizumab (5 mg/kg) every 2 weeks for 6 months. For 2 years, all of the craniospinal tumors were stable without neurological deterioration after the completion of chemotherapy. CONCLUSION: Meningiomas and schwannomas grow slowly in most patients with NF-2, but these multiple craniospinal tumors can show sudden rapid growth and manifest as neurological symptoms in a pediatric patient. These tumors could be controlled with local symptomatic and systemic bevacizumab treatments.

Intravenous Tirofiban Infusion After Angioplasty and Stenting in Intracranial Atherosclerotic Stenosis-Related Stroke.

Background and Purpose: This study aimed to investigate the effectiveness and safety of intravenous infusion of tirofiban after emergent angioplasty with or without stenting in patients with intracranial atherosclerotic stenosis-related large-vessel occlusion stroke. Methods: We performed a retrospective case series study of 98 patients who underwent thrombectomy followed by angioplasty with or without stenting to treat intracranial atherosclerotic stenosis-related large-vessel occlusion. Patients were divided into 2 groups: those who received continuous intravenous infusion of tirofiban for 12 hours after procedure (intravenous tirofiban group, n=30) and those who did not receive postprocedural intravenous tirofiban (control group, n=68). The following treatment outcomes in the 2 groups were compared: early reocclusion of treated arteries on computed tomography angiography, parenchymal hematoma, symptomatic hemorrhage, and 90-day functional outcome. Results: Early reocclusion occurred in 18 patients (18.4%). The rate of early reocclusion was significantly lower in the intravenous tirofiban group than in the control group (3.3% versus 25%, P<0.001). The rates of parenchymal hematoma, symptomatic hemorrhage, 90-day good outcome, and mortality were not significantly different between the 2 groups. In multivariate logistic analysis, the only independent predictor of early reocclusion was no use of intravenous tirofiban (odds ratio, 9.212 [95% CI, 1.155-73.495], P=0.036). A good outcome (90-day modified Rankin Scale score of 0-2) was significantly less frequent in patients with early reocclusion than in those without it (16.7% versus 72.5%, P<0.001). Conclusions: The use of intravenous tirofiban for 12 hours was associated with decreased risk of early reocclusion of treated arteries, with no increased risk of hemorrhage after emergent angioplasty, with or without stenting, in patients with intracranial atherosclerotic stenosis-related large-vessel occlusion stroke. Early reocclusion was associated with a poor outcome in such cases.

Impact of isolated basal ganglia infarction at pretreatment DWI on outcomes after endovascular thrombectomy in acute anterior circulation stroke.

PURPOSE: Acute infarction confined to the basal ganglia (BG) is occasionally observed on baseline imaging before endovascular thrombectomy. This study aimed to investigate the impact of isolated BG infarction revealed on pretreatment DWI in a large cohort of patients with acute anterior circulation stroke who underwent thrombectomy. METHODS: We retrospectively analyzed clinical and DWI data from 328 patients who underwent thrombectomy for emergent occlusions of the intracranial internal carotid artery or the middle cerebral artery. Characteristics and treatment outcomes were compared between patients with isolated BG infarction and those with non-isolated BG infarction. Binary logistic regression analyses were performed to identify independent predictors of good outcome (90-day mRS 0-2). RESULTS: Isolated BG infarction was found in 57 patients (17.4%). Patients with isolated BG infarction had a higher incidence of underlying severe intracranial atherosclerotic stenosis (21.1% vs. 10.7%, P = 0.032) than those with non-isolated BG infarction. Successful reperfusion occurred more frequently in patients with isolated BG infarction than those with non-isolated BG infarction (93% vs. 79%, odds ratio 3.529, 95% confidence interval 1.226-10.161, P = 0.014). On multivariate logistic regression analysis, independent predictors of good outcome were age, DWI-ASPECTS, and admission NIHSS score. There was no significant difference in the rate of good outcome between the two groups (54.4% vs. 42.8%, P = 0.110). CONCLUSION: Isolated BG infarction on pretreatment DWI may predict successful reperfusion after endovascular thrombectomy in patients with acute anterior circulation stroke. In addition, our study suggested a novel finding that isolated BG infarction was more frequently associated with underlying severe ICAS than non-isolated BG infarction.

The Application of Magnetic Resonance Imaging-Deformed 11C-Methionine-Positron Emission Tomography Images in Stereotactic Radiosurgery.

BACKGROUND: Although 11C-methionine positron emission tomography (MET-PET) images can be fused with magnetic resonance (MR) images using planning software for gamma knife radiosurgery (GKR), the stereotactic information has limited value in patients with recurrent malignant brain tumor due to the difference in imaging protocols between MET-PET and MR images. The aim of this study was to evaluate the clinical application of MR imaging (MRI)-deformed MET-PET images in GKR using a deformable registration tool. METHODS: We examined the enhanced MR stereotactic images, MET-PET and MRI-deformed MET-PET images without stereotactic information for 12 newly developed metastatic brain tumors. MET-PET and MRI-deformed MET-PET images were co-registered with the MR stereotactic images using radiosurgery planning software. Visual analysis was performed to determine whether the MET-PET and MR images matched better after using the deformable registration tool. In addition, the matching volume between MR and MET-PET images was compared before and after applying this tool. The matching volume was calculated as the metabolic tumor volume on the MET-PET images, including the MR-enhanced volume. The matching percentage was calculated as the matching volume divided by the MR-enhanced volume, multiplied by 100. RESULTS: Visual analysis revealed that the MRI-deformed MET-PET images provided the same axial plane as that of the MR images, with the same window level, enabling easy identification of the tumor with the radiosurgery planning software. The mean matching percentage of the MET-PET/MR fusion images was 61.1% (range 24.7-94.7) and that of the MRI-deformed MET-PET/MR fusion images was 63.4% (range 20.8-94.3). No significant difference was found in the matching percentage between the two types of fusion images (p = 0.754). CONCLUSIONS: The MRI-deformed MET-PET images enable utilization of the functional information when planning a treatment in GKR without significant volume change.

Metabolic alterations in a rat model of hepatic ischaemia reperfusion injury: In vivo hyperpolarized 13 C MRS and metabolic imaging.

BACKGROUND & AIMS: Despite a number of studies addressing the pathophysiology of hepatic IRI, a gold standard test for early diagnosis and evaluation of IRI remains elusive. This study investigated the metabolic alterations in a rat model of hepatic IRI using the in vivo hyperpolarized ¹³C MRS and metabolic imaging. METHODS: Hyperpolarized 13 C MRS with IVIM-DWI was performed on the liver of 7 sham-operated control rats and 7 rats before and after hepatic IRI. RESULTS: The hepatic IRI-induced rats showed significantly higher ratios of [1-13 C] alanine/pyruvate, [1-13 C] alanine/tC, [1-13 C] lactate/pyruvate and [1-13 C] lactate/tC compared with both sham-operated controls and rats before IRI, whereas [1-13 C] pyruvate/tC ratio was decreased in IRI-induced rats. In IVIM-DWI study, apparent diffusion coefficient (ADC), f and D values in rats after hepatic IRI were significantly lower than those of rats before IRI and sham-operated controls. The levels of [1-13 C] alanine and [1-13 C] lactate were negatively correlated with ADC, f and D values, whereas the level of [1-13 C] pyruvate was positively correlated with these values. CONCLUSIONS: The levels of [1-13 C] alanine, [1-13 C] lactate and [1-13 C] pyruvate in conjunction with IVIM-DWI will be helpful to evaluate the hepatic IRI as well as these findings can be useful in understanding the biochemical mechanism associated with hepatic damage.

Disseminated juvenile xanthogranuloma occurring after treatment of Langerhans cell histiocytosis: a case report.

CASE PRESENTATION: An 11-year-old boy presented with a complaint of a painful temporal mass. Brain magnetic resonance imaging (MRI) showed a 3-cm-sized, homogeneously enhancing mass in the greater wing of the left sphenoid bone, which was diagnosed as Langerhans cell histiocytosis (LCH). Chemotherapy with vincristine and prednisolone was performed for 1 year. After 1 year and 11 months off treatment, he developed symptoms such as polydipsia and polyuria. Brain MRI showed thickening of the pituitary stalk with enhancement, suggestive of LCH involvement, and no recurrence in the sphenoid bone. After 4 years and 4 months off treatment, he developed multiple, subcutaneous, asymptomatic, and yellowish variable-sized papules on his face, posterior neck, and back, which were pathologically diagnosed as juvenile xanthogranuloma (JXG). Brain MRI revealed multifocal enhancing skull lesions in the left parietal, right frontal, and left occipital bones, which were also diagnosed as JXG. After 5 years and 8 months off treatment, the number of variable-sized skin lesions was increased without changes in the lesions in the skull and pituitary stalk. CONCLUSION: We report a case of disseminated JXG occurring after treatment of LCH. These clinical co-presentations suggested a close relationship between their pathogenesis.

Visual outcome after endoscopic third ventriculostomy for hydrocephalus.

PURPOSE: Hydrocephalus-related symptoms are mostly improved after successful endoscopic third ventriculostomy (ETV). However, visual symptoms can be different. This study was focused on visual symptoms. We analyzed the magnetic resonance images (MRI) of the orbit and visual outcomes. METHODS: From August 2006 to November 2016, 50 patients with hydrocephalus underwent ETV. The male-to-female ratio was 33:17, and the median age was 61 years (range, 5-74 years). There were 18 pediatric and 32 adult patients. Abnormal orbital MRI findings included prominent subarachnoid space around the optic nerves and vertical tortuosity of the optic nerves. We retrospectively analyzed clinical symptoms, causes of hydrocephalus, ETV success score (ETVSS), ETV success rate, ETV complications, orbital MRI findings, and visual impairment score (VIS). RESULTS: The median duration of follow-up was 59 months (range, 3-113 months). The most common symptoms were headache, vomiting, and gait disturbance. Visual symptoms were found in 6 patients (12%). The most common causes of hydrocephalus were posterior fossa tumor in 13 patients, pineal tumor in 12, aqueductal stenosis in 8, thalamic malignant glioma in 7, and tectal glioma in 4. ETVSS was 70 in 3 patients, 80 in 34 patients, and 90 in 13 patients. ETV success rate was 80%. ETVSS 70 showed the trend in short-term survival compared to ETVSS 90 and 80. ETV complications included epidural hematoma requiring operation in one patient, transient hemiparesis in two patients, and infection in two patients. Preoperative abnormal orbital MRI findings were found in 18 patients and postoperative findings in 7 patients. Four of six patients with visual symptoms had abnormal MR findings. Three patients did not show VIS improvement, including two with severe visual symptoms. CONCLUSIONS: Patients with severe visual impairment were found to have bad outcomes. The visual symptoms related with increased intracranial pressure should be carefully monitored and controlled to improve outcomes.

A Mild Form of COG5 Defect Showing Early-Childhood-Onset Friedreich's-Ataxia-Like Phenotypes with Isolated Cerebellar Atrophy.

Progressive cerebellar ataxias are rare diseases during childhood, especially under 6 years of age. In a single family, three affected siblings exhibited Friedreich's-ataxia-like phenotypes before 2 years of age. They had progressive cerebellar atrophy, intellectual disability, and scoliosis. Although their phenotypes were similar to those observed in patients with autosomal recessive cerebellar ataxias, other phenotypes (e.g., seizure, movement disorders, ophthalmologic disturbance, cardiomyopathy, and cutaneous disorders) were not noted in this family. Whole-exome sequencing of the family members revealed one potential heterozygous mutation (c.1209delG, NM_181733.2; p.Met403IlefsX3, NP_859422.2) of the gene encoding conserved oligomeric Golgi complex subunit 5 (COG5). The heterozygous deletion at the fifth base in exon 12 of COG5 caused a frameshift and premature stop. Western blotting of COG5 proteins in the skin tissues from an affected proband showed a significantly decreased level of full length COG5 and smaller, aberrant COG5 proteins. We reported a milder form of COG5 defect showing Friedreich's-ataxia-like phenotypes without hypotonia, microcephaly, and short stature that were observed in most patients with COG5 defect.

Predictors of Good Outcome After Stent-Retriever Thrombectomy in Acute Basilar Artery Occlusion.

BACKGROUND AND PURPOSE: Factors related to prognosis after a modern mechanical thrombectomy in patients with acute basilar artery occlusion remain unclear. This study investigated the prognostic factors for patients with acute basilar artery occlusion who underwent a stent-retriever thrombectomy. METHODS: We analyzed clinical and pretreatment diffusion-weighted imaging (DWI) data in 50 consecutive patients with acute basilar artery occlusion treated with stent-retriever thrombectomy. A good outcome was defined as a modified Rankin Scale score of 0 to 2 at 3 months. The association between clinical and DWI parameters and functional outcome was evaluated with logistic regression analysis. RESULTS: In a univariate analysis, the following variables were significantly associated with outcome: age, hypertension, baseline National Institutes of Health Stroke Scale, posterior circulation Acute Stroke Prognosis Early CT Score on a pretreatment DWI, posterior circulation Acute Stroke Prognosis Early CT Score of ≥7 (versus <7), thalamic infarction, and bilateral thalamic infarction. In a multivariate model, only a low initial National Institutes of Health Stroke Scale score (odds ratio, 0.82; 95% confidence interval, 0.709-0.949; P=0.008) and high DWI posterior circulation Acute Stroke Prognosis Early CT Score (odds ratio, 1.854; 95% confidence interval 1.012-3.397; P=0.045) were significant independent predictors of good outcome. In a univariate analysis, bilateral thalamic infarction was associated with a poor outcome (odds ratio, 1.993; 95% confidence interval, 1.187-3.346; P=0.035) but not with a unilateral thalamic infarction (P=0.525). CONCLUSIONS: This study suggested that initial infarction severity and posterior circulation Acute Stroke Prognosis Early CT Score on a pretreatment DWI are independent predictors of clinical outcome after stent-retriever thrombectomy in patients with acute basilar artery occlusion.

Pediatric brainstem abscess with hemorrhage mimicking diffuse intrinsic pontine glioma: a case report.

PURPOSE: We report a rare case of brainstem abscess with hemorrhage mimicking diffuse intrinsic pontine glioma (DIPG). METHODS: A 7-month-old baby girl presented with lethargy and poor oral feeding. She had the mild fever for 1 month. Brain computed tomography revealed the hypodense lesion in the pons. Brain magnetic resonance images (MRI) showed around 1.4-cm-sized rim-enhanced mass with perilesional edema and internal hemorrhage in the pons. The cerebral blood volume was increased in the rim-enhanced area. The provisional diagnosis was DIPG, but the mass did not show the expansile mass with encasement of the basilar artery on the ventral pons. RESULTS: The biopsy was done via the floor of the fourth ventricle, and the pathologic findings showed the many inflammatory cells and CD68-immunopositive macrophage which were compatible with abscess. The antibiotics with ceftriaxone and metronidazole were administrated for 11 weeks, and the follow-up MRI showed the slightly small enhanced lesion without central necrotic area. Three years later, follow-up MRI revealed the encephalomalacic change and atrophy of the pons. She had the stable neurologic deficit of left facial palsy and right hemiparesis. CONCLUSION: The biopsy could be necessary for pontine lesions without typical radiologic findings of DIPG.

Progressive Multiple Cavernous Angiomas after Radiotherapy in a Pediatric Patient with Medulloblastoma: A Case Report.

BACKGROUND: We report a case of progressive multiple cavernous angiomas. PATIENT AND METHOD: A 16-year-old boy presented with a 2-month history of headache and dizziness. Six years earlier, he underwent surgery for cerebellar medulloblastoma and subsequent chemoradiotherapy according to the M-051 protocol of the Korean Society of Pediatric Neuro-Oncology. Follow-up brain magnetic resonance imaging (MRI) revealed a tiny hemorrhage on the cerebellum 3 months after 23.4-Gy craniospinal and 32.4-Gy boost radiotherapy. RESULT: The multiple hemorrhagic lesions had progressively developed on the whole brain without any symptoms for 6 years. On admission, MRI revealed a 1.5-cm enlarged mass with subacute hemorrhage on the right frontal area. The mass was totally removed and diagnosed as cavernous angioma. However, 5 months later, the patient complained of a headache. MRI revealed 1.4- and 0.7-cm enlarged masses on the left frontal and right temporal areas with internal hemorrhage, respectively. The left frontal mass was totally removed, and the histopathological finding was suggestive of cavernous angioma. CONCLUSION: This case showed early-developed multiple hemorrhagic lesions after radiotherapy, which had been progressive and were associated with some symptomatic cavernous angiomas. Pediatric patients with brain radiotherapy should undergo radiological check-up to identify vascular lesions, especially symptomatic patients.

Cavernous hemangioma of the third ventricle: a case report and review of the literature.

BACKGROUND: Although cavernous hemangiomas (CHs) can be found anywhere in the central nervous system, CHs of the third ventricle have been reported in only 29 patients (including our case). In the current case report, we discuss the clinical characteristics and surgical outcome of CHs of the third ventricle. CASE PRESENTATION: A 64-year-old female was admitted to our emergency room with a sudden decreased level of consciousness. Brain imaging studies demonstrated a multi-lobulated hemorrhagic mass in the third ventricle. The lesion was removed via the transcallosal-interforniceal approach and pathologically diagnosed as CH. Postoperatively, the patient had a transient neurological deficit due to hypothalamic injury and recovered to the normal status at 2 months after the operation. In the review of 29 cases, the mean age of the patients was 40 years with a slight female preponderance (female/male, 17/12). The majority of the patients complained of a mass effect with signs of increased intracranial pressure; only one case was asymptomatic. Gross total resection was achieved in 81% of the cases. Around 80% of the patients were asymptomatic or improved from the initial symptoms. Mortality rate was 6.9% and the most common complication was hydrocephalus. CONCLUSIONS: As demonstrated in the review of the previous reports, the outcome is favorable after surgical excision for CH of the third ventricle. Hence, surgical excision appears to be the treatment of choice for CH located in the third ventricle, which tends to grow rapidly resulting in a mass effect.

The difference in diffusion-weighted imaging with apparent diffusion coefficient between spontaneous and postoperative intracranial infection.

BACKGROUND: Although the roles of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) have been accepted as the initial or confirmatory diagnostic tool for spontaneous intracranial infections, the usefulness of these has rarely been investigated in intracranial infections after a craniotomy procedure. Through an analysis of the clinico-radiological characteristics of spontaneous and postoperative intracranial infections, the authors revealed the specific factors that affect the accuracy of DWI and ADC in diagnosing intracranial infections. METHODS: The authors retrospectively analyzed 67 intracranial infections confirmed using preoperative MR imaging, including the DWI, ADC and gadolium-enhanced (Gd) images, and by peroperative pus drainage. RESULTS: In 67 enrolled patients, no or uncertain diffusion restriction on DWI and ADC was found in 9 cases (13%). All the cases showed typical peripheral enhancement on Gd images. Among nine cases without diffusion restriction, postoperative infection was seen in five cases (62.5% [5/8 postoperative infection group] vs. 6.8% [4/59 spontaneous infection group], p = 0.001). On multivariate analysis, postoperative infection was the predictive factor for false-negative restriction on DWI and ADC (hazard ratio: 41.2, 95% confidential index: 2.39-710.25, p = 0.01). CONCLUSION: Despite the excellent availability of DWI and ADC for diagnosing spontaneous intracranial infections, negative restriction results of those images are not sufficient to exclude postoperative intracranial infection.

Ruptured venous aneurysm associated with a dural arteriovenous fistula: Two case reports.

BACKGROUND: In general, venous aneurysm associated with dural arteriovenous fistula (dAVF) is considered to be developed under long standing venous hypertension and manifested as venous ectasia of draining vein itself. However, discrete saccular shaped venous aneurysm without angiographic evidence of venous hypertension arising from the draining vein, like cerebral arterial aneurysm, is quite rare and its pathomechanism remains unclear in patients with dAVF. CASE SUMMARY: In this report, we present two cases of ruptured saccular venous aneurysms associated with dAVF without venous hypertension or venous ectasia. In both cases, significant curve or stenosis is observed in draining vein, which is located in just distal portion of the venous aneurysms. These aneurysms were successfully treated with a transarterial embolization. Underlying mechanism of venous aneurysms in these cases is discussed. CONCLUSION: Although there is little doubt that hemodynamic stress has a critical role in the development of venous aneurysms in patients with dAVF, preceding venous hypertension or venous ectasia is not necessary for development and enlargement of venous aneurysms. Considering the significant risk of rupture, a careful review of draining vein features including tortuosity or stenosis is needed, especially in venous aneurysms without evidence of venous hypertension.

Electroencephalography-based classification of Alzheimer's disease spectrum during computer-based cognitive testing.

Alzheimer's disease (AD) is a progressive disease leading to cognitive decline, and to prevent it, researchers seek to diagnose mild cognitive impairment (MCI) early. Particularly, non-amnestic MCI (naMCI) is often mistaken for normal aging as the representative symptom of AD, memory decline, is absent. Subjective cognitive decline (SCD), an intermediate step between normal aging and MCI, is crucial for prediction or early detection of MCI, which determines the presence of AD spectrum pathology. We developed a computer-based cognitive task to classify the presence or absence of AD pathology and stage within the AD spectrum, and attempted to perform multi-stage classification through electroencephalography (EEG) during resting and memory encoding state. The resting and memory-encoding states of 58 patients (20 with SCD, 10 with naMCI, 18 with aMCI, and 10 with AD) were measured and classified into four groups. We extracted features that could reflect the phase, spectral, and temporal characteristics of the resting and memory-encoding states. For the classification, we compared nine machine learning models and three deep learning models using Leave-one-subject-out strategy. Significant correlations were found between the existing neurophysiological test scores and performance of our computer-based cognitive task for all cognitive domains. In all models used, the memory-encoding states realized a higher classification performance than resting states. The best model for the 4-class classification was cKNN. The highest accuracy using resting state data was 67.24%, while it was 93.10% using memory encoding state data. This study involving participants with SCD, naMCI, aMCI, and AD focused on early Alzheimer's diagnosis. The research used EEG data during resting and memory encoding states to classify these groups, demonstrating the significance of cognitive process-related brain waves for diagnosis. The computer-based cognitive task introduced in the study offers a time-efficient alternative to traditional neuropsychological tests, showing a strong correlation with their results and serving as a valuable tool to assess cognitive impairment with reduced bias.

Differentiating between Lymphoma and Metastasis Presenting as Solid Cerebellar Mass Lacking Necrosis.

Objectives: This study aimed to identify radiologic features that differentiate lymphoma from metastasis manifesting as a solid enhancing mass lacking necrosis in the cerebellum. Methods: Pathologically confirmed 24 primary central nervous system lymphoma (PCNSL) and 32 metastasis patients with solid enhancing cerebellar masses without necrotic or hemorrhagic components were retrospectively analyzed. We evaluated the imaging characteristics using contrast-enhanced magnetic resonance imaging (MRI). The serrate sign was defined as a tumor spreading along white matter with branch-like enhancement or outward spikes. Results: The serrate sign was exclusively identified in the PCNSL group, showing a significant difference compared to the metastasis group (75.0% vs. 0%, p < 0.001). Homogeneous enhancement occurred more frequently in PCNSL than in metastasis (91.7% vs. 21.9%, p < 0.001). Conversely, bulging contour (62.5% vs. 4.2%, p < 0.001) and surface involvement (71.9% vs. 29.2%, p = 0.003) were more prevalent in metastasis than PCNSL. For predicting PCNSL, the serrate sign demonstrated 75.0% sensitivity, 100% specificity, 100% positive predictive value, 84.2% negative predictive value, and 89.3% accuracy. Conclusions: This study found that the serrate sign and homogeneous enhancement are reliable MRI features for differentiating cerebellar PCNSL from metastasis, whereas a bulging contour and surface involvement suggest metastasis. The serrate sign demonstrated diagnostic significance in differentiating PCNSL from metastasis.

Magnet-Guided Temozolomide and Ferucarbotran Loaded Nanoparticles to Enhance Therapeutic Efficacy in Glioma Model.

Background. The aim of the study was to synthesize liposomal nanoparticles loaded with temozolomide and ferucarbotran (LTF) and to evaluate the theranostic effect of LTF in the glioma model. Methods. We synthesized an LTF that could pass through the Blood Brain Barrier (BBB) and localize in brain tumor tissue with the help of magnet guidance. We examined the chemical characteristics. Cellular uptake and cytotoxicity studies were conducted in vitro. A biodistribution and tumor inhibition study was conduted using an in vivo glioma model. Results. The particle size and surface charge of LTF show 108 nm and -38 mV, respectively. Additionally, the presence of ferucarbotran significantly increased the contrast agent effect of glioma compared to the control group in MR imaging. Magnet-guided LTF significantly reduced the tumor size compared to control and other groups. Furthermore, compared to the control group, our results demonstrate a significant inhibition in brain tumor size and an increase in lifespan. Conclusions. These findings suggest that the LTF with magnetic guidance represents a novel approach to address current obstacles, such as BBB penetration of nanoparticles and drug resistance. Magnet-guided LTF is able to enhance therapeutic efficacy in mouse brain glioma.