Iatrogenic Vertebral Arteriovenous Fistula Involving Brachiocephalic Vein Due to Central Venous Catheterization: A Case Report.

PURPOSE: To report a case of vertebral arteriovenous fistula (VAVF) caused by iatrogenic trauma of central venous catheterization (CVC) involving brachiocephalic vein (BCV). CASE REPORT: A 79-year-old female was referred for assessment of a vertebral artery (VA) aneurysm at the V1 segment. The patient had no signs other than a vascular murmur on the right neck and was diagnosed 20 years after undergoing CVC. Right vertebral angiography revealed a high-flow shunt from the V1 segment of the right VA and draining into the right BCV. The fistula had a single communication between a pseudoaneurysm and large varix. We diagnosed the patient with CVCinduced VAVF (CIVAVF) involving BCV and obliterated the shunt by selective transarterial and transvenous embolization of the pseudoaneurysm under flow control using a balloon catheter with no complications. CONCLUSION: This case highlights the point that CIVAVF involving BCV is rare but possible. In addition, there is a possibility that CIVAVF involving BCV does not demonstrate the findings of arterial steal or retrograde venous drainage and is undiagnosed for a long term due to lack of neurological manifestation and other subjective symptoms. We also showed that endovascular treatment can be feasible and useful for CIVAVF involving BCV.

Radiological and clinical features of twig-like middle cerebral artery in comparison with moyamoya angiopathy: a multicenter retrospective study.

OBJECTIVE: Twig-like middle cerebral artery (T-MCA) is a rare congenital anomaly that is difficult to distinguish from moyamoya angiopathy (MMA), given the similarity of the angioarchitectures. The aim of this study was to gain insights into the radiological and clinical features of T-MCA and to distinguish this condition from MMA. METHODS: A multicenter retrospective study was conducted in 29 patients with T-MCA and 57 patients with MMA. Demographic, radiological, and clinical data were compared between the patients with T-MCA and those with MMA. RESULTS: The T-MCA group tended to be older than the MMA group (mean age 47 ± 18 vs 39 ± 22 years). Twenty patients with T-MCA (69%) were initially diagnosed with MMA. All T-MCA cases had twig-like networks and steno-occlusive changes involving the MCA. The T-MCA group had a higher incidence of intracranial aneurysms (35% vs 11%) and coexisting arterial anomalies (48% vs 12%). T-MCA and MMA cases had significant differences in involvement of the internal carotid artery terminus (0% vs 100%) and posterior cerebral artery (0% vs 23%), and in transdural anastomosis (0% vs 51%). T-MCA cases were less likely to present with stroke (59% vs 86%) and more likely to be asymptomatic (28% vs 12%). Of the patients with stroke, those with T-MCA had more hemorrhagic strokes (41% vs 29%) and fewer ischemic strokes (59% vs 71%) compared to those with MMA. CONCLUSIONS: This study suggests that T-MCA is a different disease entity from MMA based on significant differences in the radiological and clinical features. Neurosurgeons should recognize this anomaly and understand the key features that differentiate T-MCA from MMA.

Super-selective balloon test occlusion with electrophysiological monitoring to occlude angiographically invisible posterior communicating artery perforators with unruptured aneurysm.

Balloon test occlusion (BTO) can predict the ischemic complication risk associated with arterial occlusion. We present a case of an unruptured, broad-necked internal carotid artery-posterior communicating artery (PcomA) aneurysm that was successfully embolized after super-selective BTO of fetal PcomA with electrophysiological monitoring. The proximal portion of the PcomA was internally occluded without causing major neurological deficits, although we observed a small new infarction in the ipsilateral anterior thalamus postoperatively. We recognized small perforators arising from the proximal PcomA during a previous clipping surgery. Super-selective BTO with electrophysiological monitoring could be useful for functional preservation after infarction from angiographically invisible perforators.

Early rebleeding of a foramen magnum dural arteriovenous fistula: A case report and review of the literature.

Foramen magnum dural arteriovenous fistula (FM-DAVF) is a subset of craniocervical junction arteriovenous fistulas. We report a rare case of FM-DAVF with early rebleeding and review the literature. A 50-year-old man experienced 3 episodes of intracranial bleeding from a vessel malformation in the acute stage. We identified an FM-DAVF, supplied by multiple feeding arteries (eg, left ascending pharyngeal artery) that drained into the straight sinus and left superior petrosal sinus. The draining vein had venous varices. We performed transarterial feeder embolization and surgical disconnection of the DAVF. Early rebleeding of FM-DAVF is rare. High-risk patients require risk assessment and appropriate treatment as soon as possible in the acute stage.

Aplastic or Twig-Like Middle Cerebral Artery Presenting with Intracerebral Hemorrhage During Pregnancy: Report of Two Cases.

BACKGROUND: An aplastic or twig-like middle cerebral artery (Ap/T-MCA) is a rare congenital anomaly that can present with both ischemic and hemorrhagic stroke. The etiology of this pathology has remained unclear. Here, we report 2 cases of intracerebral hemorrhage (ICH) owing to an Ap/T-MCA in pregnant patients. CASE DESCRIPTION: In both patients, cerebral angiography revealed a steno-occlusive lesion and an abnormal arterial network on the unilateral middle cerebral artery. One patient was treated conservatively for a putaminal hemorrhage, and a cesarean section was performed uneventfully 6 months after onset of the ICH. The other patient underwent a craniotomy for evacuation of the lobar hemorrhage. Subsequently, a cesarean section was performed uneventfully. Both patients gradually recovered without significant disabilities. CONCLUSIONS: An Ap/T-MCA is a rare congenital anomaly and is a potential cause of ICH for pregnant patients. A cesarean section is a useful option for pregnant patients with this condition.

Periprocedural Outcomes of Carotid Artery Stenting in Elderly Patients.

BACKGROUND: Carotid artery stenting has emerged as an alternative to carotid endarterectomy especially in patients with high risk of carotid endarterectomy. Older age (≥80 years old) was recognized as one of the high risk factors of carotid endarterectomy. However, the association between older age and increased risk of adverse events for carotid artery stenting has been reported. The purpose of this study was to evaluate the association between age and periprocedural outcomes after carotid artery stenting. METHODS: A total of 126 symptomatic and asymptomatic cases of carotid artery stenosis were treated with tailored carotid artery stenting. The type of stents and embolic protection devices were chosen according to clinical and morphologic characteristics of the patients. Procedural, imaging, and clinical outcomes were retrospectively assessed and compared between the elderly patients group (≥80 years old) and the non-elderly patients group (<80 years old). RESULTS: Clinical and morphologic characteristics except for dyslipidemia were not significantly different between the 2 groups. Periprocedural neurologic complications were not significantly different between the 2 groups (P = .095). Minor stroke occurred more frequently in the elderly patients group (P = .021). However, the frequency of major stroke was not significantly different between the 2 groups (P = 1). Presence of new ischemic lesions on postprocedural examination was not significantly different between the 2 groups (P = .84). Myocardial infarction and death did not occur in either group. CONCLUSIONS: Carotid artery stenting can be performed safely in elderly patients, comparable with non-elderly patients.

Complications and Predictors of Hypotension Requiring Vasopressor after Carotid Artery Stenting.

A significant controversy exists regarding the clinical impact of hemodynamic depression on major adverse events after carotid artery stenting (CAS). The purpose of this study was to evaluate the incidence, predictors, and clinical significance of hypotension after CAS. A total of 118 cases of carotid artery stenosis were treated with CAS. Hypotension was defined as sustained systolic blood pressure <80 mmHg and requiring intravenous administration of vasopressor to maintain adequate systolic blood pressure after the procedure. Baseline characteristics, procedural characteristics, and periprocedural major adverse events were retrospectively compared between postprocedural hypotension group and non-hypotension group. Morphological and procedural characteristics were not significantly different between the two groups. Periprocedural major adverse events, presence of new ischemic lesions, and number of new ischemic lesions were not significantly different between the two groups (P = 1, P = 0.36, P = 0.68). Hypertension was an independent protective factor (P = 0.037), and use of proximal protection and the distance from carotid bifurcation to maximum stenotic lesion ≤ 10 mm were independent risk factors for developing hypotension after CAS (P = 0.034, P = 0.027). There was no significant relationship between hypotension after CAS and major adverse events in this study. Maintenance of periprocedural adequate cerebral perfusion is thought to be important to prevent ischemic complications due to hypotension after CAS, especially in these cases.

Relationship between preoperative magnetic resonance imaging and surgical findings: aneurysm wall thickness on high-resolution T1-weighted imaging and contact with surrounding tissue on steady-state free precession imaging.

This study evaluated the aneurysm wall thickness by high-resolution T1-weighted imaging and the contact between the aneurysm and surrounding tissue by steady-state free precession (SSFP) imaging. The surgical findings were prospectively compared with these preoperative magnetic resonance (MR) imaging findings in 35 consecutive patients with 37 unruptured cerebral aneurysms (UCAs). The aneurysm wall was not visible in 13 UCAs, but was visible in 23. Subarachnoid space between the aneurysm and surrounding tissue was visible in 16 UCAs, a visible layer of cerebrospinal fluid (CSF) between the aneurysm and surrounding tissue in 12, and no visible layer in 7. MR imaging predicted the surgical findings in 29 UCAs (78%), showed different findings in six UCAs (16%), and two (5%) could not be evaluated due to insufficient quality of preoperative MR images. Among the UCAs with different findings, five UCAs had a partially thin wall even though high-resolution T1-weighted imaging had shown a visible wall, and one UCA showed less contact with the surrounding tissue even though the SSFP imaging had shown no visible CSF layer. In conclusion, high-resolution T1-weighted imaging and SSFP imaging provided significant additional preoperative information regarding UCAs and the surrounding tissue.

Trigonal cavernous malformation with intraventricular hemorrhage: a case report and literature review.

We reported a case of trigonal cavernous malformation (CM) with intraventricular hemorrhage. This 67-year-old woman experienced sudden onset of loss of consciousness and her Glasgow Coma Scale (GCS) was 5 points (E1V1M3) on admission. CT scan demonstrated intraventricular hemorrhage and acute hydrocephalus. Angiography did not demonstrate any vascular abnormality. Ventricular drainage was performed for acute hydrocephalus and the postoperative course was good. CT showed a hyperdense lesion in the left trigone, which was contrast-enhanced on T1-weighted MR. Removal of CM was performed via the left middle temporal sulcus. We conducted a Pub Med search for trigonal CM and found 17 cases. Herein we discuss the symptoms, CT and MR findings and treatment.

Rare variant of persistent primitive hypoglossal artery, arising from the external carotid artery.

A 63-year-old man presented with an extremely rare variant of persistent primitive hypoglossal artery (PHA), which was found incidentally during examination for a contralateral asymptomatic internal carotid artery (ICA) stenosis. This anastomotic vessel arose from the external carotid artery, not the ICA, and joined the vertebrobasilar artery through the hypoglossal canal. Persistent PHA is rare and the reported incidence is 0.027-0.26%. Recognition of the existence of this variant vessel and preservation during neuroradiologic intervention or surgery is important to prevent possible ischemic complications.

Endovascular recanalization of the completely occluded internal carotid artery using a flow reversal system at the subacute to chronic stage.

OBJECT: The efficacy and pitfalls of endovascular recanalization were evaluated in cases of internal carotid artery (ICA) occlusion in the subacute to chronic stage. METHODS: Fourteen cases (15 lesions) of symptomatic ICA occlusion with hemodynamic compromise or recurrent symptoms were treated at the subacute to chronic stage using an endovascular technique. The Parodi embolic protection system was used during the recanalization procedure to prevent embolic stroke by reversing the flow from the distal ICA to the common carotid artery. RESULTS: Recanalization of the occluded ICA was possible in 14 of 15 lesions. The occlusion points were 10 cervical ICAs and 4 petrous/cavernous ICAs in successfully recanalized cases. Ischemic symptoms disappeared completely after the treatment, and new ischemic symptoms did not appear related to the treated lesion. Single photon emission computed tomography findings demonstrated the improvement of hemodynamic compromise in all cases. One case showed right middle cerebral artery branch occlusion during the procedure, but this patient's neurological symptoms were stable due to preexisting hemiparesis. Endovascular recanalization was possible and effective in improving hemodynamic compromise. However, there are still several problems with this technique, such as hyperperfusion syndrome after recanalization, cerebral embolism during treatment, durability after treatment, and identification of the occlusion point before treatment. CONCLUSIONS: Endovascular recanalization using an embolic protection device can be considered as an alternative treatment for symptomatic ICA occlusion with hemodynamic compromise or refractoriness to antiplatelet therapy, even in the subacute to chronic stage of the illness.

[Carotid artery stenting via a transbrachial artery: techniques and problems].

Recently, carotid artery stenting (CAS) has been reported to be an alternative of carotid endarterectomy (CEA) for internal carotid artery (ICA) stenosis due to the improvement of protection devices. In general, the transfemoral approach has been chosen for CAS because of the sizes of the devices. However, the transfemoral route seems to be unavailable or at high risk, in cases of severe atherosclerotic changes or aneurysm of the femoral, iliac artery or aorta, or after bypass graft placement. In this report, we presented 5 patients who underwent CAS using the transbrachial approach. The mean stenotic rate of 84% before treatment was reduced to 14% after the procedures. The 30-day morbidity and mortality were both 0%. Major local complications at the puncture site were not encountered. There has been no stroke nor death during a mean follow-up period of 6 months. We suggest that CAS via transbrachial route is an effective and safe treatment for ICA stenosis, by use of low-profile devices and bi-plane DSA equipment, especially in patients who are not eligible for the transfemoral access.

[A case of intraosseous meningioma with extracranial progression having difficulty in making a preoperative diagnosis].

Intraosseous meningioma is very rare and is often confused preoperatively with a primary bone tumor of the skull. We report a case of intraosseous meningioma with hyperostosis for which preoperative diagnosis was difficult. A 78-year-old female with a slowly growing hard mass in the left parietal bone was admitted. Neurological findings were normal. Plain skull radiograph showed a 6 x 6 cm hyperostotic lesion in the left parietal bone. Bone window CT scan showed thickening and hyperostosis in the same area. MRI using Gd-DTPA showed heterogeneous enhancement of the intraosseous mass, and homogenous enhancement of the dura matter. And angiogram showed a tumor stain fed by the bilateral superficial temporal artery and the It-occipital artery. The tumor and the underlying dura mater were totally removed. Preoperative diagnosis was an osteogenic tumor, but histological examination revealed a transitional meningioma. We discussed the development and the classification of an ectopic meningioma and the mechanism of hyperostosis. We should be aware of the existence of intraosseous menigiomas mimicking osteogenic tumors.

[A chronic intracerebral hematoma for which corticosteroid was effective: case report].

Chronic intracerebral hematoma is rare. Computerized tomography almost consistently demonstrates ring-shaped lesions with mass effect and perifocal edema. All patients in published studies have been treated surgically. Most of the hematomas have been encapsulated and contained blood in various stages of organization. The thick capsule has usually consisted of an outer layer of collagenous tissue and an inner layer of granulation tissue. A 60-year-old male, who had had sudden neurological symptoms, left hemiparesis and aphasia, was admitted to our hospital. Fourteen days after admission, CT revealed an expanding low density mass with brain edema. He was treated surgically and with corticosteroid. In this case, the surgical treatment was not effective but the corticosteroid medication was effective. Strategies of treatment are discussed.