A juvenile case of epilepsy-associated, isocitrate dehydrogenase wild-type/histone 3 wild-type diffuse glioma with a rare BRAF A598T mutation.

Here, we report a juvenile (18-year-old male) case of epilepsy-associated, isocitrate dehydrogenase wild-type/histone 3 wild-type diffuse glioma with a rare BRAF mutation and a focal atypical feature resembling diffuse astrocytoma. The patient presented with refractory temporal lobe epilepsy. Subsequently, magnetic resonance imaging revealed a hyperintense lesion in the right temporal lobe on fluid attenuated inversion recovery images. The patient underwent right lateral temporal lobectomy and amygdalohippocampectomy. Histopathologically, the tumor showed isomorphic, diffuse, infiltrative proliferation of glial tumor cells and intense CD34 immunoreactivity. The tumor cells were immunonegative for isocitrate dehydrogenase 1 (IDH1) R132H and BRAF V600E. Notably, the tumor cells showed the lack of nuclear staining for α-thalassemia/mental retardation syndrome, X-linked (ATRX). In addition, the Ki-67 labeling index, using a monoclonal antibody MIB-1, was elevated focally at tumor cells with p53 immunoreactivity. Molecular analyses identified a BRAFA598T mutation, the first case reported in a glioma. BRAFA598T is predicted to result in loss of kinase action; however, inactive mutants can stimulate mitogen-activated protein kinase kinase (MEK)-extracellular signal-regulated kinase (ERK) signaling through CRAF activation. Thus, according to the recent update of the consortium to inform molecular and practical approaches to central nervous system tumor taxonomy (cIMPACT-NOW update 4), our case is also compatible with diffuse glioma with the mitogen-activated protein kinase (MAPK) pathway alteration. Thorough immunohistochemical and molecular studies are necessary for diagnosis of epilepsy-associated, diffuse gliomas. Partial resemblance in histopathological and molecular genetic features to diffuse astrocytoma also calls for attention.

Surgical histopathology of limited dorsal myeloschisis with flat skin lesion.

PURPOSE: Limited dorsal myeloschisis (LDM) is characterized by two invariable features: a focal closed neural tube defect and a fibroneural stalk linking the skin lesion to the underlying spinal cord. Although detailed histopathological findings of the LDM stalk were originally described by Pang et al., the precise relationship between the histopathological findings and clinical manifestations including intraoperative findings has not been fully determined. METHODS: We retrospectively analyzed the histopathological findings of the almost entire stalk and their relevance to the clinical manifestations in six Japanese LDM patients with flat skin lesions. RESULTS: Glial fibrillary acidic protein (GFAP)-immunopositive neuroglial tissues were observed in three of the six patients. Unlike neuroglial tissues, peripheral nerve fibers were observed in every stalk. In four patients, dermal melanocytosis, "Mongolian spot," was seen surrounding the cigarette-burn lesion. In three of these four patients, numerous melanocytes were distributed linearly along the long axis of the LDM stalk, which might represent migration of melanocytes from trunk neural crest cells during formation of the LDM stalk. CONCLUSION: Immunopositivity for GFAP in the LDM stalk was observed in as few as 50% of our patients, despite the relatively extensive histopathological examination. We confirm that the clinical diagnosis of LDM should be made based on comprehensive histopathological examination as well as clinical manifestations. The profuse network of peripheral nerve fibers in every stalk and the high incidence of melanocyte accumulation associated with dermal melanocytosis might assist the histopathological diagnosis of LDM.

First-in-human trial of Stabilizer device in neuroendovascular therapy.

Objectives: Flow diverter or stent implantation to intracranial target lesion requires large inner diameter microcatheter navigation. The exchange method using stiff long wire is often necessary if it is difficult to navigate over the regular guidewire. However, this method has an intrinsic risk of vessel damage and may cause severe complications. We investigated the safety and efficacy of a new device, the Stabilizer device for navigation in a first-in-human clinical trial under the Certified Review Board agreement. Materials and methods: The Stabilizer is a 320 cm length exchange wire with a stent for anchoring and is compatible with a 0.0165" microcatheter. The trial design is a prospective single-arm open-label registry. Inclusion criteria are elective flow diverter treatment or stent-assisted coiling, expected to be difficult to navigate a microcatheter with a regular micro guidewire, and obtained documented consent. The primary endpoint of the study was a hemorrhagic complication. Results: Five patients were enrolled in this trial. The median age is 52 years, ranges from 41 to 70, and all patients were female. Three aneurysms were located on the internal carotid artery, one on the vertebral artery, and one on the basilar artery. Basilar artery aneurysm was treated by stent-assisted coiling and others were treated by flow diverter deployment. All cases successfully navigate microcatheter for the treatment by the trial method using Stabilizer device without any adverse event. Conclusions: The results from this first-in-human consecutive five cases show the safety of the Stabilizer device in neuro-endovascular therapy for navigation of devices to the intracranial target lesion.

Effectiveness of the Digging through Thrombus Technique by Using an Aspiration Catheter and Stent Retriever for Cerebral Venous Thrombosis.

Cerebral venous thrombosis (CVT) is a rare cause of stroke, and the first-line treatment is systemic anticoagulation. Patients unresponsive to standard therapy for CVT present with rapid neurological deterioration and require endovascular treatment. We encountered two patients with severe CVT who underwent endovascular treatment. In our cases, the thrombus was too hard and extensive to pass through using currently existing techniques. We performed the "digging through thrombus technique" using an aspiration catheter and stent retriever and achieved rapid sinus recanalization and favorable outcomes.

Narrowing of the angle of the parent artery after coil embolization increases the risk for aneurysm recurrence.

OBJECTIVE: Aneurysm recurrence after coiling is a major complication in some cases, including cases of repeated recurrences. In this study, we identified a relationship between the recurrence of a coiled aneurysm and angle change of the parent artery. METHODS: From April 2008 to December 2019, we performed 283 coil embolizations to treat 256 aneurysms in 251 patients. Among these, 21 cases of recurrent saccular aneurysms were selected. The parent artery angle changes between the initial treatment and the first re-treatment were compared between those who underwent single re-treatment and showed no recurrence after the first re-treatment (Group SR, n = 14) and those who required multiple re-treatments (Group MR, n = 7). RESULTS: The parent artery angles at the first treatment [medians (interquartile ranges)] were 121.6° (109.3-135.6°) in Group SR and 104.9° (89.9-131.0°) in Group MR; at the second treatment, these angles were 121.2° (105.5-132.7°) and 81.9° (67.0-111.4°), respectively, revealing angle changes of -2.2° (-4.0 to -0.4°) and -16.4° (-30.1 to -8.6°) in Groups SR and MR between the first and second treatments. The between-group differences in the parent artery angles at the second treatment and the changes in the parent artery angle between the first and second treatments were statistically significant. CONCLUSION: In patients with recurrent aneurysms, simple aneurysm coiling is not effective when the angle of the parent artery becomes narrower after treatment, relative to that before treatment. Stent placement should be considered for straightening the parent artery or diverting blood flow.

Mechanical Thrombectomy of Primary Distal Anterior Cerebral Artery Occlusion: A Case Report.

OBJECTIVE: Primary anterior cerebral artery (ACA) occlusion is a rare condition and sometimes leads to significant neurological deficits. We herein report on the efficacy of mechanical thrombectomy (MT) in treating the distal ACA occlusion in a clinical setting. CASE PRESENTATION: A 76-year-old woman presented with a sudden onset of right hemiparesis. Computed tomographic angiography and perfusion imaging and subsequent analysis with RAPID software revealed acute left ACA occlusion with salvageable penumbra. The patient obtained a score of 11 on the National Institutes of Health Stroke Scale. MT was performed for occlusion of the left ACA (A4), and successful reperfusion (Thrombolysis in Cerebral Infarction score of 3) was achieved on the first attempt using a stent retriever. The patient's recovery progressed well, and she was discharged 13 days after admission with a modified Rankin Scale score of 1. CONCLUSION: This case report demonstrates the clinical efficacy, safety, and favorable clinical outcome of treating a primary distal ACA occlusion with MT.