Posterior condylar canal dural arteriovenous fistula: anatomical, symptomatological, and therapeutic considerations in comparison with hypoglossal canal dural arteriovenous fistula.

BACKGROUND: Posterior condylar canal dural arteriovenous fistulas (dAVFs) are extremely rare. METHODS: We report a case series and literature review of posterior condylar canal dAVFs and discuss similarities and differences between posterior condylar and hypoglossal canal dAVFs with respect to the related vascular anatomy, angioarchitecture of the fistula, presentation, and treatment. RESULTS: Four cases of posterior condylar canal dAVF were identified at our institutions and six cases were identified in the literature. Posterior condylar canal dAVFs were predominantly frequent in relatively young women. All patients presented with pulsatile tinnitus. There was no history of hemorrhage as there was no cortical venous reflux. This is different from hypoglossal canal dAVFs which can present with myelopathy or hemorrhage from cortical venous reflux. Transvenous embolization was safe and eliminated the symptoms. Palliative transarterial embolization can be an option to mitigate the symptoms, although there is a potential risk of cranial nerve palsy or lateral medullary stroke. CONCLUSIONS: Posterior condylar canal dAVFs are generally benign lesions. However, intolerable tinnitus may require intervention. Transvenous embolization is effective and safe.

Early detection of large-vessel occlusion stroke after cardiac surgery using CT angiography leading to early recanalization with endovascular thrombectomy.

CT angiography may be useful for early diagnosis of ischemic stroke after cardiac surgery. When patients diagnosed with large-vessel occlusion, endovascular thrombectomy may be a therapeutic option and may improve their neurological complications.

Duplicated Middle Cerebral Artery Aneurysms Treated by Coil Embolization; A Report of Two Cases and Literature Review.

BACKGROUND: Duplication of the middle cerebral artery (DMCA) is an anomalous vessel arising from the internal carotid artery (ICA). Aneurysms at the origin of a DMCA have been reported; however, most have been treated with clipping surgery. Here, we describe two cases of aneurysms at the origin of a DMCA treated with coil embolization. CASE PRESENTATION: Case 1: A seventy-three year-old man presented with severe headache and was diagnosed with subarachnoid hemorrhage (SAH). Digital subtraction angiography (DSA) and 3-dimensional (3-D) DSA showed an aneurysm arising from a DMCA. Coil embolization was performed with DMCA patency. The patient had an uneventful postoperative course. CASE 1: A 44-year-old woman presented with a history of clipping for an IC-anterior choroidal artery (AchA) aneurysm 8 years prior. Magnetic resonance imaging (MRI) showed regrowth of the aneurysm. 3-D DSA showed an IC-DMCA aneurysm located laterally and distal to the AchA. The DMCA arose from the bottom of the aneurysm. Coil embolization was performed without DMCA occlusion and showed no postoperative ischemic changes. CONCLUSION: An IC-DMCA aneurysm is rare and may be misdiagnosed as an AchA aneurysm. Clinicians should perform a 3D-DSA evaluation if the aneurysm arises from the lateral wall of the IC to obtain a precise diagnosis and to preserve the DMCA during coil embolization.

Clinical outcome after microsurgical resection of intraventricular trigone meningiomas: a single-centre analysis of 20 years and literature overview.

BACKGROUND: Outcome and treatment-associated morbidity analysis of trigone meningioma surgery. METHODS: We retrospectively assessed 27 neurosurgically treated patients (median age 63 years, range 15-84) between 1999 and 2019. The median preoperative Karnofsky Performance Scale (KPS) was 80 (range 20-100), and the majority (78%) suffered from tumour-specific symptoms. The most frequent symptoms were aphasia (n = 6), visual field deficits (n = 5), and increased intracranial pressure (n = 5). The median tumour volume was 11.2 cm3 (range 3.9-220.5). The most common approaches were the transtemporal (n = 17) and transparietal routes (n = 5). RESULTS: At last follow-up (median follow-up 35 months, range 3-127), the median KPS was 90 (range 30-100); eleven (42%) patients had improved, nine (35%) were unchanged, six (23%) had worsened, and one was lost to follow-up. One year after surgery, 18/21 (86%) patients had retained an activity level similar or improved compared with preoperatively. No surgery-related mortality was recorded. Postoperative new neurological deficits were seen in 13 (48%) patients; eight suffered from permanent, most commonly motor deficits (n = 4), and five of transient deficits. Permanent new motor deficits improved in the majority of affected patients (3/4) over time. New deficits were more often seen for transtemporal (8/17) than transparietal approaches (1/5). Patients with postoperative permanent new deficits had a significantly worse KPS at last follow-up (p < 0.001). CONCLUSIONS: The transtemporal and transparietal approaches provide good access, but the latter might provide for a better risk profile. Patients show favourable outcome, but there is a considerable risk for new neurological deficits. This must be taken into consideration for oligosymptomatic patients.

Recurrent periventricular hemorrhage in cerebral proliferative angiopathy: Case report.

Cerebral proliferative angiopathy (CPA) is a rare vascular lesion. Bleeding from CPA is uncommon, but the risk of rebleeding is high once it bleeds. We describe a case of CPA with multiple intra- and periventricular hemorrhages during 30-year follow-up. Recurrent bleeding in these areas are common in moyamoya disease. These lesions may share the cause of bleeding: proliferation of the periventricular vessels functioning as collateral pathways. Revascularization surgery for CPA may attenuate the vascular proliferation in the vicinity of the ventricle, which may prevent rebleeding.

Bazedoxifene, a selective estrogen receptor modulator, reduces cerebral aneurysm rupture in Ovariectomized rats.

BACKGROUND: Estrogen deficiency is thought to be responsible for the higher frequency of aneurysmal subarachnoid hemorrhage in post- than premenopausal women. Estrogen replacement therapy appears to reduce this risk but is associated with significant side effects. We tested our hypothesis that bazedoxifene, a clinically used selective estrogen receptor (ER) modulator with fewer estrogenic side effects, reduces cerebral aneurysm rupture in a new model of ovariectomized rats. METHODS: Ten-week-old female Sprague-Dawley rats were subjected to ovariectomy, hemodynamic changes, and hypertension to induce aneurysms (ovariectomized aneurysm rats) and treated with vehicle or with 0.3 or 1.0 mg/kg/day bazedoxifene. They were compared with sham-ovariectomized rats subjected to hypertension and hemodynamic changes (HT rats). The vasoprotective effects of bazedoxifene and the mechanisms underlying its efficacy were analyzed. RESULTS: During 12 weeks of observation, the incidence of aneurysm rupture was 52% in ovariectomized rats. With no effect on the blood pressure, treatment with 0.3 or 1.0 mg/kg/day bazedoxifene lowered this rate to 11 and 17%, almost the same as in HT rats (17%). In ovariectomized rats, the mRNA level of ERα, ERß, and the tissue inhibitor of metalloproteinase-2 was downregulated in the cerebral artery prone to rupture at 5 weeks after aneurysm induction; the mRNA level of interleukin-1ß and the matrix metalloproteinase-9 was upregulated. In HT rats, bazedoxifene restored the mRNA level of ERα and ERß and decreased the level of interleukin-1ß and matrix metalloproteinase-9. These findings suggest that bazedoxifene was protective against aneurysmal rupture by alleviating the vascular inflammation and degradation exacerbated by the decrease in ERα and ERß. CONCLUSIONS: Our observation that bazedoxifene decreased the incidence of aneurysmal rupture in ovariectomized rats warrants further studies to validate this response in humans.

Presigmoid Approach to Vertebrobasilar Artery Aneurysms: A Series of 31 Patients and Review of the Literature.

OBJECTIVE: The presigmoid approach can be used to treat vertebrobasilar artery aneurysms when circumstances require more operative exposure. High morbidity and mortality in these cases have been reported. In this study, we describe our modified presigmoid approach for vertebrobasilar artery aneurysms and our clinical results. METHODS: This series includes patients with vertebrobasilar aneurysms clipped via the modified presigmoid approach at the Department of Neurosurgery at Helsinki University Hospital from 1998 to 2014. Data were collected from the operating record books, patients' medical records, and a radiologic database server. RESULTS: Thirty-three presigmoid procedures of 31 patients were performed to treat 34 aneurysms (14 ruptured, 20 unruptured). The aneurysms had a mean distance from the posterior clinoid process to the aneurysm neck of 12.2 mm (range, 0-26.6 mm). A favorable outcome was achieved in 21 patients (64%). A favorable outcome was achieved in 74% of unruptured and good-grade patients, whereas favorable outcome was achieved in only 36% of poor-grade patients. Complete or near-complete occlusion was achieved in 79%. Larger aneurysms, fusiform morphology, and anterior dome projection had lower occlusion rates. CONCLUSIONS: We have described our experiences of using the presigmoid approach to treat vertebrobasilar aneurysms. The clinical and radiographic results are acceptable given the complex location and configuration of the treated aneurysms. Unfavorable outcomes are related to the poor admission Hunt and Hess grade, aneurysm morphology, and aneurysm size.

The role of estrogen on the pathology of cerebral aneurysms.

INTRODUCTION: Epidemiological studies suggest that postmenopausal estrogen deficiency is responsible for the increased risk of aneurysmal subarachnoid hemorrhage, while menopausal hormone therapy is protective against cerebral aneurysms. These findings indicate the critical role of estrogen in the pathophysiology of cerebral aneurysm. AREAS COVERED: Here, we provide a narrative review for understanding the roles of estrogen and estrogen receptors in the pathogenesis of cerebral aneurysms. A specific selective estrogen receptor modulator is a potential drug for cerebral aneurysms, since it may favorably interact with estrogen receptors while avoiding unwanted side effects related to estrogen therapy. Expert Commentary: Future investigations into the role of estrogen on cerebral aneurysm pathophysiology may lead to the development of a novel drug, which interacts with estrogen receptors to modify the pathological mechanism of cerebral aneurysm formation on postmenopausal women.

Factors Determining Surgical Approaches to Basilar Bifurcation Aneurysms and Its Surgical Outcomes.

BACKGROUND: The basilar bifurcation aneurysm (BBA) is still considered to be one of the most challenging aneurysms for micro- and endovascular surgery. Classic surgical approaches, such as subtemporal, lateral supraorbital (LSO), and modified presigmoid, are still reliable and effective. OBJECTIVE: To analyze the clinical and radiological factors that affect the selection of these classic surgical approaches and their outcomes. METHODS: A retrospective analysis was conducted on the clinical and radiological data from computed tomographic angiography of BBA that have been clipped in the Department of Neurosurgery of Helsinki University Central Hospital between 2004 and 2014. Statistical analyses were performed using parametric and nonparametric tests where values were considered significant below P = .05. RESULTS: One hundred four patients with BBA underwent surgical clipping in our department between 2004 and 2014. Eight patients were excluded from the study because of incomplete preoperative radiological evaluations, leaving 96 patients for further analysis. Multiple aneurysm clipping, mean basilar bifurcation angle, and aneurysm neck distance from posterior clinoid process were shown to be factors that determine the surgical approach. Unfavorable outcome is strongly associated with poor Hunt-Hess grade on admission, distance from aneurysm neck (the posterior clinoid process), thrombosis, and dome size. CONCLUSION: Microsurgery for BBA clipping can be performed safely with simple surgical approaches: subtemporal and LSO. There are several factors determining the approach selected. Poor patient outcome in BBA was highly associated with poor preoperative clinical grade and large size of aneurysm dome.

Venous-Preserving Sylvian Dissection.

OBJECTIVE: The Sylvian fissure has been dissected through the frontal side of the superficial Sylvian veins with sacrifice of the tributaries of the frontal superficial Sylvian vein, which may lead to venous infarction. In addition, disturbed venous drainage makes the brain susceptible to brain retraction. Therefore, preservation of the vein is essential in modern neurosurgery to decrease morbidity. METHODS: We describe the technical nuances of Sylvian dissection with an emphasis on preserving the veins. RESULTS: The arachnoid between the frontal and temporal superficial Sylvian veins is divided as to enter the fissure. After the deep part in the Sylvian fissure is reached, the inside of the fissure is dissected along the "microvascular Sylvian fissure," the temporal side of the frontal vessels or the frontal side of the temporal vessels. The Sylvian fissure is dissected in a deep-to-superficial and posterior-to-anterior fashion ("paperknife technique") up to the skull base. The frontal superficial Sylvian vein usually tethers the brain to the dura, restricting the surgical corridor when approaching deep lesions. Peeling off the arachnoid that wraps this vein ("denude technique") allows the vein to stretch. CONCLUSIONS: Keeping the proper dissection plane ("microvascular Sylvian fissure") is crucial to preserve the veins. The "paperknife technique" makes the division of the frontal and temporal lobe easier. The "denude technique" provides a wider space between the frontal lobe and the skull base. These techniques make it possible to obtain a sufficiently wide surgical corridor to the basal cistern without sacrificing the veins and their tributaries.

Aneurysmal subarachnoid hemorrhage: pathobiology, current treatment and future directions.

Aneurysmal subarachnoid hemorrhage is the most devastating form of stroke. Many pathological mechanisms ensue after cerebral aneurysm rupture, including hydrocephalus, apoptosis of endothelial cells and neurons, cerebral edema, loss of blood-brain barrier, abnormal cerebral autoregulation, microthrombosis, cortical spreading depolarization and macrovascular vasospasm. Although studied extensively through experimental and clinical trials, current treatment guidelines to prevent delayed cerebral ischemia is limited to oral nimodipine, maintenance of euvolemia, induction of hypertension if ischemic signs occur and endovascular therapy for patients with continued ischemia after induced hypertension. Future investigations will involve agents targeting vasodilation, anticoagulation, inhibition of apoptosis pathways, free radical neutralization, suppression of cortical spreading depolarization and attenuation of inflammation.

Role of bypass surgery and balloon occlusion test for the endovascular management of fusiform dissecting aneurysms. Report of two cases.

Fusiform intracranial aneurysm is one of the most difficult pathologies to treat. The role and efficacy of recent advanced endovascular technique and conventional bypass surgery are discussed.

Takotsubo cardiomyopathy following subarachnoid haemorrhage.

A 67-year-old woman was admitted with aneurysmal subarachnoid haemorrhage and a 12-lead ECG showed ST segment elevation. Transthoracic echocardiography confirmed akinesis of the left ventricular mid-apical segment, with an ejection fraction of 26%, features characteristic of takotsubo cardiomyopathy. Five days later, we identified thrombus in the apex of the left ventricle. Sixteen days after onset, the thrombus had disappeared and wall motion improved (ejection fraction 58%) without evidence of cardioembolism. Takotsubo cardiomyopathy is a cause of cardiac dysfunction after stroke, including SAH. It is characterised by transiently depressed contractile function of the left mid and apical ventricle, without obstructive coronary artery disease. Clinicians should suspect takotsubo cardiomyopathy in patients with subarachnoid haemorrhage who have an ECG abnormality. Echocardiography is needed to detect the distinctive regional wall motion abnormality. Despite its severity in the acute phase, takotsubo cardiomyopathy is self-limiting and its management is conservative.

Spontaneous resolution of delayed onset large subclavian artery pseudoaneurysm.

A 70-year-old woman with a history of end-stage renal disease secondary to anti-neutrophil cytoplasmic autoantibody-associated vasculitis had been receiving hemodialysis for 5 years. The patient underwent attempted right internal jugular vein cannulation for temporary hemodialysis catheter placement. Pulsating mass developed in the neck and angiography revealed a subclavian artery pseudoaneurysm 4 days later. The pseudoaneurysm disappeared spontaneously during the interval between the diagnosis and the planned surgical procedure. Such delayed onset and spontaneous resolution of subclavian artery pseudoaneurysm is uncommon. Close observation may be optimal if delayed onset of pseudoaneurysm occurs after small needle puncture with cessation of antiplatelet/anticoagulant administration.

Middle meningeal artery aneurysm associated with meningioma.

Middle meningeal artery aneurysm associated with meningioma is extremely rare, and only two cases have previously been reported. In our case, a 72-year-old woman with convexity meningioma underwent preoperative cerebral angiography, which revealed a flow-related aneurysm on the middle meningeal artery. Embolization of the aneurysm was performed with N-butycyanoacrylate glue, and complete obliteration was confirmed under craniotomy. In order to eliminate the risk of preoperative rupture resulting in intracranial hemorrhage, endovascular embolization with liquid glue is safe and effective for this kind of aneurysm.