Factors Associated with Early and Late Seizure Related to Aneurysmal Subarachnoid Hemorrhage.

Post-stroke epilepsy may occur after aneurysmal subarachnoid hemorrhage (aSAH). Both early and late seizures could cause severe neurocognitive deficits if administration of appropriate antiseizure medication is delayed. Therefore, it is important to elucidate the risk factors for early and late seizures, which could be shared with medical teams to promptly manage seizures. There are aspects of both hemorrhage and ischemia in aSAH, and thus, numerous risk factors are considered for early and late seizures. We examined factors associated with aSAH-related early and late seizures. Among 297 patients who had aSAH and underwent direct or endovascular surgery, 25 had early seizures and 20 had late seizures. Patients who did not experience any seizures in at least 2-years of follow-up (n = 81) were used as the control group. Early seizures were associated with older age and acute severe nonneurological infection, whereas late seizures were associated with intraparenchymal lesion volume >10 mL and shunt placement. In patients with late seizures, consistency was frequently observed between electroencephalogram and the presence of intraparenchymal lesions. The frontopolar electrode on electroencephalogram was highly sensitive to abnormality in early seizures. Early seizures were induced by the patient's systemic factors, which may lower the threshold for cortical excitability. Patients with intraparenchymal lesions who undergo shunt placement should be carefully followed up for late seizures.

Giant cell arteritis with severe intracranial involvement diagnosed and treated early.

Background: Ischemic cerebrovascular accidents (CVA) occur in 3.3-7.2% of patients with giant cell arteritis (GCA), and intracranial vessels are rarely affected. We, herein, report a case of intracranial GCA with rapidly progressive multiple intracranial vascular lesions. Case Description: A 76-year-old woman visited a local doctor due to a headache; then, it improved spontaneously. Three months later, she suddenly had cerebral infarctions of bilateral pons and cerebellum. Magnetic resonance angiography (MRA) revealed the left internal carotid artery (ICA) occlusion, the right vertebral artery (VA) occlusion, and the left VA stenosis. She was diagnosed with atherothrombotic stroke and dual antiplatelet therapy was administered. However, 2 weeks later, the left VA stenosis was aggravated. Therefore, we reviewed the data of MRA performed 3 months ago and noted no lesions in the ICA and VA. T1 black-blood post-gadolinium imaging sequence magnetic resonance imaging (MRI) revealed vessel wall enhancement in the bilateral VA, left ICA, and bilateral superficial temporal artery. We performed a temporal artery biopsy and diagnosed her with GCA. The progression of the intracranial vascular lesions was decelerated by oral glucocorticoid administration. Conclusion: Intracranial vascular lesions in GCA can be formed later than initial symptoms, such as headache, and aggravated despite improvement in headache. In patients with GCA, evaluating intracranial vessels as a control is useful for distinguishing them from arteriosclerotic lesions at the onset of CVA. Intracranial GCA is characterized by rapidly progressive vascular lesions in the bilateral ICA and VA. In addition, T1 black-blood post-gadolinium imaging sequence MRI may lead to early diagnosis and treatment.

Analysis of the Anatomical Factors Affecting Ability to Navigate Penumbra Catheter through Internal Carotid Siphon.

Objective: The efficacy and safety of aspiration thrombectomy using Penumbra catheter with acute large vessel occlusion in the anterior circulation have been reported in previous studies. In some cases, the carotid siphon (CS) is elongated, and with this anatomy, especially where there is bifurcation of the ophthalmic artery (OA), navigation of Penumbra catheters into distal internal carotid artery (ICA) is interrupted, which is known as the 'ledge effect'. We investigate the anatomical characteristics of CS that cause interruption of navigation of the Penumbra catheter. Methods: Between January 2015 and March 2018, mechanical thrombectomy using Penumbra 60 was performed on 51 patients with middle cerebral artery (MCA) or intracranial ICA occlusion. Patients were divided into two groups: The 'ledge-effect' group those in whom the Penumbra catheter was unable to be navigated into the distal ICA through the CS, and 'no ledge-effect' group those in whom this was possible. The anatomical characteristics of CS, the diameter of ICA, diameter of OA, OA/ICA ratio and radius of the CS were evaluated using angiographical imaging. Results: The 'ledge-effect' group numbered eight cases (17%). Only the value of the CS radius was significantly smaller in the ledge-effect group (p = 0.0019), other parameters were not significantly different between the groups. The cutoff radius value was 3.62 mm. Conclusion: The most notable anatomical factor affecting possibility of navigation of the Penumbra catheter through the CS was the CS radius. This could be useful information when devices used in mechanical thrombectomy are selected.

[Tentorial Dural Arteriovenous Fistula Presenting with Ocular Symptoms:A Case Report].

Tentorial dural arteriovenous fistula(dAVF)is classified as Cognard 4 with a high risk of aggressive feature, such as intracranial hemorrhage, venous infarction, and intracranial hypertension. We report a rare case presenting with ocular symptoms caused by tentorial dAVF. A 59-year-old man presented with progressive chemosis and exophthalmos of his left eye. Angiography showed a tentorial dAVF that was primarily fed by the middle meningeal artery and the meningohypophyseal artery. The AVF drained into the superior ophthalmic vein and the cerebellar cortical vein via an enlarged petrosal vein. Because transarterial Onyx embolization resulted in incomplete obliteration of the fistula, he underwent microsurgery via a suboccipital approach to obliterate the shunt. Postoperative angiography showed complete obliteration of the shunt. His ocular symptoms rapidly cured. We present this rare case and discuss the pathomechanism associated with the development of ocular symptoms secondary to a tentorial dAVF from the viewpoint of microvascular anatomy.

Observation of Neointimal Coverage Around the Aneurysm Neck After Stent-Assisted Coil Embolization by Optical Frequency Domain Imaging: Technical Case Report.

BACKGROUND AND IMPORTANCE: Stent-assisted coil embolization has been established as a treatment option for wide-necked or complex aneurysms. However, concerns have been raised about the incidence of thromboembolic complications, which is higher for coil embolization without stent assistance. Long-term antiplatelet therapy is necessary to prevent acute or delayed ischemic events potentially associated with incomplete stent apposition after treatment with stent-assisted coil embolization. Optical frequency domain imaging (OFDI) provides excellent-resolution images of intraluminal structures, allowing evaluation of the outcomes of stent-assisted procedures in terms of stent apposition and neointimal coverage. We here describe the novel use of OFDI for the observation of intravascular tissue formation after stent-assisted coil embolization. CLINICAL PRESENTATION: Two patients were treated with stent-assisted coil embolization for unruptured vertebral artery aneurysm. At the 1- or 2-yr follow-up visit, routine angiography followed by OFDI were performed to evaluate neointimal coverage of the stent strut and stent apposition to the vascular wall. OFDI enabled clear visualization of the vessel wall structures and demonstrated complete coverage of the stent struts as well as full stent wall apposition in 1 patient and incomplete coverage near the aneurism neck as well as mallaposition of some struts in the other patient. CONCLUSION: OFDI represents a feasible modality for the evaluation of intracranial vasculature and the outcomes of stent-assisted coil embolization in terms of intimal healing of aneurysms, stent-vessel interactions, and neointimal coverage of the stent. Such information is helpful in determining the duration of antiplatelet therapy after stent-assisted coil embolization.

A case of dural arteriovenous fistula draining to the diploic vein presenting with intracerebral hemorrhage.

The authors report an unusual case of a dural arteriovenous fistula (dAVF) draining only to the diploic vein and causing intracerebral hemorrhage. A 62-year-old woman presented with disturbance of consciousness and left hemiparesis. Brain CT scanning on admission showed a right frontal subcortical hemorrhage. Digital subtraction angiography revealed an arteriovenous shunt located in the region around the pterion, which connected the frontal branch of the right middle meningeal artery with the anterior temporal diploic vein and drained into cortical veins in a retrograde manner through the falcine vein. The dAVF was successfully obliterated by percutaneous transarterial embolization with N-butyl-2-cyanoacrylate. The mechanism of retrograde cortical venous reflux causing intracerebral hemorrhage is discussed.

A case of in-stent neoatherosclerosis 10 years after carotid artery stent implantation: observation with optical coherence tomography and plaque histological findings.

We report a patient's case of slow progressive in-stent restenosis 10 years after bare-metal stent implantation to his carotid artery. We treated the patient with an additional stent placement under a distal filter protection device. Optical coherence tomographic assessment and plaque histology during the carotid artery stenting (CAS) revealed atheromatous change at in-stent neointima, which contained lipid-rich plaque and calcification deposits. These findings suggest that in-stent neoatherosclerosis may play an important role in the pathogenesis of very late stent restenosis after CAS.

[Bone drilling in microvascular decompression for trigeminal neuralgia: high morphological variety of the petrous bone].

Microvascular decompression is now a standard surgical technique for the treatment of trigeminal neuralgia. However, it is occasionally difficult to expose the trigeminal nerves because of the high anatomical variety of vascular or bony structures in the posterior fossa. We reported the case of a 59-year-old woman with trigeminal neuralgia whose site of neurovascular compression could not be observed in microvascular decompression. On approaching the trigeminal nerve, the suprameatal tubercle was so prominent that it prevented adequate visualization of the nerve tract. After drilling out the tubercle concealing the trigeminal nerve behind it, we exposed the nerve entirely and subsequently decompressed it from the superior cerebellar artery. Retrospectively, the suprameatal tubercle was found 3mm high above the posterior surface of the petrous bone. Then, we analyzed the height of suprameatal tubercles in 106 patients who underwent three-dimensional CT of the skull. Mean values of the suprameatal tubercles were 1.4-1.7mm in height, and 5.2% of them were higher than 3mm. The result suggested the high morphological variety of the petrous bone. We emphasize the importance of presurgical evaluation of the petrous bone in trigeminal neuralgia, because the neurovascular compression site may not be exposed sufficiently by the suprameatal tubercle in approximately 5% of the patients.

Cilostazol activates function of bone marrow-derived endothelial progenitor cell for re-endothelialization in a carotid balloon injury model.

BACKGROUND: Cilostazol(CLZ) has been used as a vasodilating anti-platelet drug clinically and demonstrated to inhibit proliferation of smooth muscle cells and effect on endothelial cells. However, the effect of CLZ on re-endothelialization including bone marrow (BM)-derived endothelial progenitor cell (EPC) contribution is unclear. We have investigated the hypothesis that CLZ might accelerate re-endothelialization with EPCs. METHODOLOGY/PRINCIPAL FINDINGS: Balloon carotid denudation was performed in male Sprague-Dawley rats. CLZ group was given CLZ mixed feed from 2 weeks before carotid injury. Control group was fed normal diet. CLZ accelerated re-endothelialization at 2 weeks after surgery and resulted in a significant reduction of neointima formation 4 weeks after surgery compared with that in control group. CLZ also increased the number of circulating EPCs throughout the time course. We examined the contribution of BM-derived EPCs to re-endothelialization by BM transplantation from Tie2/lacZ mice to nude rats. The number of Tie2-regulated X-gal positive cells on injured arterial luminal surface was increased at 2 weeks after surgery in CLZ group compared with that in control group. In vitro, CLZ enhanced proliferation, adhesion and migration activity, and differentiation with mRNA upregulation of adhesion molecule integrin αvß3, chemokine receptor CXCR4 and growth factor VEGF assessed by real-time RT-PCR in rat BM-derived cultured EPCs. In addition, CLZ markedly increased the expression of SDF-1α that is a ligand of CXCR4 receptor in EPCs, in the media following vascular injury. CONCLUSIONS/SIGNIFICANCE: CLZ promotes EPC mobilization from BM and EPC recruitment to sites of arterial injury, and thereby inhibited neointima formation with acceleration of re-endothelialization with EPCs as well as pre-existing endothelial cells in a rat carotid balloon injury model. CLZ could be not only an anti-platelet agent but also a promising tool for endothelial regeneration, which is a key event for preventing atherosclerosis or restenosis after vascular intervention.