Presence of intra-aneurysmal thrombi with delayed coil migration after embolization of an aneurysmal subarachnoid hemorrhage: illustrative case.

BACKGROUND: Coil migration is a rare, but notable complication of endovascular treatment. Risk factors include communicating segment aneurysms, aneurysmal shape, and technical factors. Although cerebral blood flow obstruction caused by early coil migration requires urgent coil removal, delayed coil migration is often asymptomatic, making it difficult to determine a treatment strategy. OBSERVATIONS: A 47-year-old woman was referred to the institute with acute-onset headache. She was diagnosed with subarachnoid hemorrhage due to rupture of the right internal carotid artery-posterior communicating artery aneurysm and underwent endovascular coil embolization. Following the procedure, the patient showed no obvious complications; however, 14 days later, images showed coil migration to the distal side, leading to surgical removal. Right frontotemporal craniotomy was performed, and the remaining coil was removed. The aneurysm was clipped again, and blood flow was confirmed. The patient was discharged 12 days after the craniotomy with transient oculomotor nerve palsy. At the 15-month follow-up, there was no aneurysm recurrence and the oculomotor nerve palsy showed improvement. LESSONS: Retrieval of the migrated coil by craniotomy is an effective remedial measure; however, intraoperative complications are common. Early detection, established protocols, and prompt treatment decisions are important for preventing undesirable outcomes.

Disappearance of a moyamoya-related distal anterior cerebral artery aneurysm after target bypass revascularization: illustrative case.

BACKGROUND: Aneurysm formation is a complication of moyamoya disease (MMD). Distal anterior cerebral artery (ACA) aneurysms account for approximately 1% of MMD-related aneurysms. We report a case of target bypass for adult patients with MMD who presented with intracranial hemorrhage due to rupture of a distal ACA aneurysm, whose disappearance was confirmed postoperatively. OBSERVATIONS: A 45-year-old woman presented with sudden-onset headache and loss of consciousness. Head computed tomography showed hemorrhage in the genu of the corpus callosum with intraventricular extension. Digital subtraction angiography (DSA) revealed Suzuki stage III MMD and a left A3 segment aneurysm. Superficial temporal artery (STA)-middle cerebral artery (MCA) bypass and STA-ACA target bypass were performed to reduce hemodynamic stress on the left ACA. DSA 6 months after surgery showed patency of both bypasses and disappearance of the aneurysm. At the 20-month follow-up, the patient was asymptomatic and neurologically intact. LESSONS: Bypass revascularization may be an effective treatment to reduce hemodynamic stress and eliminate MMD-related aneurysms.

Repeated coil embolization of traumatic basilar artery pseudoaneurysm accompanied by bilateral traumatic internal carotid artery stenosis following severe head injury in a pediatric patient: A case report and literature review.

Background: Few cases of pediatric traumatic intracranial aneurysms (pTICAs) in the posterior circulation involving the basilar artery (BA) following severe head trauma have been reported. Here, we describe a pediatric case of traumatic BA pseudoaneurysm accompanied by bilateral traumatic internal carotid artery (ICA) stenosis following blunt head trauma. Case Description: A 16-year-old boy presented to our emergency department after being hit by a car. The patient was initially diagnosed with multiple skull base fractures underlying traumatic subarachnoid hemorrhage and left acute epidural hematoma. Seven days following emergency craniectomy, magnetic resonance imaging revealed bilateral ICA stenosis, BA stenosis, and BA pseudoaneurysm. We decided to perform coil embolization, resulting in body filling and a volume embolization ratio of 15.7%. Twenty-eight days after coil embolization, digital subtraction angiography revealed aneurysmal rupture. We performed repeated coil embolization, resulting in body filling and a volume embolization ratio of 20.9%. Conclusion: We reported a pediatric case of traumatic BA pseudoaneurysm accompanied by bilateral traumatic ICA stenosis following a severe head injury treated with repeated coil embolization. Considering the risk of further brain injury due to high incidence of rupture, early vascular survey and appropriate treatment may be the most important prognostic factors in pTICAs.

Manual superficial temporal artery compression using a circular plastic material for embolization of meningioma: illustrative case.

BACKGROUND: In meningiomas that occur in the high-convexity region, the superficial temporal artery (STA) frequently feeds the tumor, and when embolizing from the middle meningeal artery (MMA), the embolic material may not reach the tumor vessels because of the pressure gradient resulting from the STA blood flow, resulting in inadequate embolization. In this case, a circular plastic material was used to apply circumferential pressure around the parietal foramen to control blood flow to the tumor. OBSERVATIONS: A 45-year-old male underwent head magnetic resonance imaging that revealed a 2.2-cm meningioma in the right high-convexity region. Preoperative embolization was performed. When N-butyl-2-cyanoacrylate was injected from the right MMA while using a circular plastic material to compress the skin around the parietal foramen through which the bilateral STAs (the tumor feeders) flow, it was able to fully penetrate the tumor vessel and occlude the other feeders in a retrograde manner. The patient underwent tumor removal after embolization uneventfully. LESSONS: Manual compression of the STA using a circular plastic material is useful when the tumor is fed by the STA through the parietal foramen and is also applicable to transarterial embolization of dural arteriovenous fistulas fed by the STA or occipital artery.

[Microvascular Decompression to Treat Abducens Nerve Paralysis Caused by Compression of the Anterior Inferior Cerebellar Artery:A Case Report].

Microvascular decompression(MVD)is an effective treatment for hemifacial spasm and trigeminal neuralgia. However, there are few reports regarding its use with abducens nerve palsy. Here, we report the case of a 77-year-old male who presented with diplopia and was admitted to our facility for right abducens nerve palsy. MRI constructive interference in steady-state(CISS)showed that the right anterior inferior cerebellar artery(AICA)was curved in a posterior-superior direction at the beginning of the region of origin, causing compression of the root exit zone of the right abducens nerve. In addition, MRI showed an unruptured fusiform aneurysm(5.3mm×7.1mm)of the vertebral artery(VA)involving the posterior inferior cerebellar artery(PICA). However it was not related to abducens nerve paralysis. The aneurysm was successfully treated with an occipital artery-posterior inferior cerebellar artery(OA-PICA)bypass and clipping of the proximal VA and PICA origin. The position of the offending artery was moved using a Teflon® felt fibrin glue and the retrosigmoid transcondylar fossa approach. The patient recovered from abducens nerve paralysis with no new neurological deficit. We emphasize the importance of choosing an appropriate approach as this increases the possibility of treating abducens nerve paralysis in a timely manner.

Endovascular therapy for hemodialysis patients with atrial fibrillation and cerebral thromboembolism: A case series.

INTRODUCTION: Hemodialysis patients with atrial fibrillation are at high risk for stroke. Intravenous recombinant tissue plasminogen activator is considered for acute ischemic stroke. However, recombinant tissue plasminogen activator therapy is contraindicated for some hemodialysis patients with atrial fibrillation. These patients and those who have received recombinant tissue plasminogen activator therapy without blood flow recovery are candidates for endovascular therapy. METHODS AND RESULTS: Three hemodialysis patients with atrial fibrillation received endovascular therapy for acute cerebral infarction. Cerebrovascular incident occurred during or after hemodialysis in two of these patients. All three patients achieved successful recanalization after endovascular therapy. CONCLUSION: In this series, endovascular therapy showed good results without complications. More cases should be investigated to obtain more evidence of successful endovascular therapy for hemodialysis patients.

Distal superior cerebellar artery aneurysm located at the newly formed anastomotic site with the long circumferential artery of the posterior cerebral artery: A case report.

We describe a case of a distal superior cerebellar artery (SCA) aneurysm that arose from a unique collateral pathway between the SCA and long circumferential artery (LCA) of the posterior cerebral artery (PCA). The patient was a 69-year-old male who was admitted to our facility for an asymptomatic and incidentally identified cerebellar aneurysm. Magnetic resonance imaging showed a saccular aneurysm arising from the right SCA in the quadrigeminal cistern. Digital subtraction angiography revealed an unusually dilated branch from the aneurysmal sac. Furthermore, this branch had retrograde flow from the quadrigeminal segment to the anterior pontomesencephalic segment, was connected to the PCA at the P1 segment, and exited from the P2 segment. We attributed this unusual angioarchitecture to collateral circulation secondary to severe P1 stenosis. Thus, the dilated unusual branch is an LCA of the PCA for supplying the distal PCA with blood flow. As a result, the aneurysm is probably formed at the junction between the SCA and LCA. Endovascular coiling for the aneurysm was successfully performed with preserved collateral system.

Posterior Inferior Cerebellar Artery Originating from the Jugular Branch of the Ascending Pharyngeal Artery.

The variation in which the posterior inferior cerebellar artery arises from the hypoglossal branch of the ascending pharyngeal artery is thought to be related to the remnant of the primitive hypoglossal artery, and is referred to as a primitive hypoglossal artery variant. Cases in which the posterior inferior cerebellar artery arises from the jugular branch of the ascending pharyngeal artery are extremely rare. The authors present a case of a 50-year-old male with vertebral artery dissection who had this extremely rare variation bilaterally. The patient also had several rare variations of the intracranial vessels. This posterior inferior cerebellar artery arising from the jugular branch of the ascending pharyngeal artery may have developed due to the anastomosis between the meningeal and the pial vessels of the posterior fossa. Alternatively, an unknown primitive anastomotic artery may have passed through the jugular foramen. Genetic factors may play an important role in the presence of this anomalous vessel.

Endovascular reconstruction for a kinked internal carotid artery after carotid endarterectomy.

BACKGROUND: Although different surgical techniques have been reported for repairing kinked stenosis of the internal carotid artery (ICA) after carotid endarterectomy (CEA), there are no reports using endovascular reconstruction. We present the details of a case successfully treated by carotid artery stenting (CAS). CASE DESCRIPTION: A 73-year-old female was referred to our department with fugacious amaurosis and transient sensory disturbance in the left upper limb due to moderate stenosis of the right ICA that was treated by CEA 28 days after admission. However, postoperative angiography and carotid Doppler revealed a kinked ICA with a high-flow velocity that was not present intraoperatively. After 3 months, she had suffered transient ischemic attacks that were refractory to medical treatment, so we performed CAS to prevent future events. The kinked ICA was immediately resolved by stenting and there was no restenosis at a follow-up angiogram 19 months later. CONCLUSIONS: This case shows that CAS could be a potential therapeutic option for the management of symptomatic kinking stenosis of the ICA after CEA.

Successful sinus restoration for transverse-sigmoid sinus dural arteriovenous fistula complicated by multiple venous sinus occlusions: The usefulness of preoperative computed tomography venography.

BACKGROUND: Although sinus restoration for transverse-sigmoid sinus (TSS) dural arteriovenous fistula (DAVF) has rarely been reported over the past decade, its advantage and indication still remain unclear. Herein, we discuss the indications and technical aspects of this therapy with a review of the literature. CASE DESCRIPTION: A 79-year-old female was referred to our department with generalized convulsion. An angiogram revealed a DAVF at the junction of the right TSS. The right sigmoid and left transverse sinuses were occluded, which resulted in remarkable leptomeningeal venous reflux and cerebral venous congestion. A preoperative computed tomography (CT) venogram precisely revealed the occluded segment of the right sigmoid sinus, which facilitated the sinus restoration with balloon percutaneous transluminal angioplasty and stenting. CONCLUSION: Sinus restoration is preferable in patients with severe cerebral venous congestion due to multiple sinus occlusions and/or a restricted collateral venous outlet. CT venography is useful for precise evaluation of the length and configuration of the occluded segment, which thus make it possible to evaluate the feasibility of stenting.

Correlation of clot imaging with endovascular recanalization in internal carotid artery terminus occlusion.

BACKGROUND AND PURPOSE: In a swine stroke model we have previously demonstrated a high-intensity fluid attenuated inversion recovery (FLAIR) signal representing the erythrocyte component of the clot. We hypothesized that the intensity of the FLAIR clot signal in patients with acute stroke may predict the efficacy of recanalization by thrombectomy devices. In this study we compared the pretreatment FLAIR signal intensity of the clots in the distal internal carotid artery (ICA) and the degree of angiographic recanalization rate after mechanical thrombectomy. METHODS: 25 consecutive acute stroke patients with ICA terminus (ICA-T) occlusion diagnosed with MRI at the UCLA Medical Center between 2002 and 2013 were retrospectively reviewed. The intensity of the FLAIR clot signal at the distal ICA was blindly compared with the angiographic recanalization status (successful recanalization defined as Thrombolysis In Cerebral Infarction (TICI) score of 2b-3) and non-successful recanalization as TICI score 0-2a) after endovascular treatment. Multivariate logistic regression analysis for successful recanalization was performed. RESULTS: Successful recanalization was achieved in 40% of patients (10/25) and showed a significantly higher FLAIR intensity (p=0.014). The cut-off value for clot intensity on the FLAIR sequence to predict recanalization was 0.7952, with 70% sensitivity and 80% specificity (95% CI 0.59 to 0.96) using a receiver operating characteristic curve. In multivariate logistic regression analysis, only a high FLAIR clot intensity (>0.7952) was associated with successful recanalization (OR 16.79; 95% CI 1.29 to 218.92; p=0.031). CONCLUSIONS: High signal intensity on FLAIR clot imaging may predict successful recanalization after endovascular therapy for ICA-T occlusion.

Disappearance of a small intracranial aneurysm as a result of vessel straightening and in-stent stenosis following use of an Enterprise vascular reconstruction device.

In-stent stenosis after stent-assisted coil embolization is a rare but well-known complication. A 32-year-old woman with an unruptured wide-necked left internal carotid artery (ICA) terminus aneurysm and an ipsilateral very small anterior choroidal artery aneurysm underwent stent-assisted coil embolization for the ICA terminus aneurysm. The 4-month follow-up angiography revealed diffuse in-stent stenosis and disappearance of the untreated anterior choroidal artery aneurysm, retaining the patency of the anterior choroidal artery. To our knowledge, this is the first report to demonstrate the course of in-stent stenosis and disappearance of an untreated small intracranial aneurysm as a result. We report this unique case and discuss the interesting mechanism underlying this phenomenon, and also provide a review of the relevant literature.

Endovascular treatment of pediatric intracranial aneurysms: a retrospective study of 35 aneurysms.

BACKGROUND: Pediatric intracranial aneurysms are rare and not well characterized in comparison with those in adults. OBJECTIVE: To analyze our institution's longitudinal experience of endovascular treatment for pediatric aneurysms to better understand this rare condition. METHODS: A retrospective record review was performed of patients aged <20 years treated with endovascular methods for intracranial aneurysms between 1995 and 2012. There were 31 patients (average 14.4±4.2 years; 20 male, 11 female) with 35 intracranial aneurysms. RESULTS: The rate of subarachnoid hemorrhage as the initial presentation was 48% and the rates of multiple and giant aneurysms were 13% and 31%, respectively; 28.5% of the cases were posterior circulation aneurysms. Fifteen saccular aneurysms occurred in 14 patients and 17 fusiform aneurysms were noted in 14 patients. Two infectious aneurysms were diagnosed in two patients and one traumatic aneurysm occurred in another patient. Thirty-four aneurysms were treated endovascularly and one had thrombosed spontaneously on a follow-up angiogram. Of the 15 saccular aneurysms, 11 were treated with conventional coiling, one was treated with stent-assisted coiling, one was treated with a flow-diverting stent and two were treated with parent vessel occlusion (PVO). Of the 17 fusiform aneurysms, 15 were treated with PVO with or without prior bypass surgery and one was treated with a flow-diverting stent. The rate of permanent complications and a favorable outcome were 2.9% and 87%, respectively. CONCLUSIONS: Endovascular treatment of pediatric aneurysms is technically feasible with an acceptable complication rate despite the high incidence of fusiform aneurysms.

Onyx embolization of anterior condylar confluence dural arteriovenous fistula.

The anterior condylar confluence (ACC) is a small complex venous structure located medial to the jugular vein and adjacent to the hypoglossal canal. To our knowledge, this is the first report of transvenous Onyx embolization for ACC dural arteriovenous fistula (DAVF). Three patients with ACC DAVF were treated using the Onyx liquid embolic agent with or without detachable coils. Complete angiographic obliteration of the fistulas was achieved in all cases without permanent lower cranial neuropathy. This report suggests that the controlled penetration of Onyx is advantageous in order to obliterate ACC DAVFs with a small amount of embolic material.

Structural analysis for Wingspan stent in a perforator model.

Perforator infarction represents a critical problem after intracranial Wingspan stent. To explore the mechanism of perforator infarction, we simulated the stent-artery interaction at an atheromatous plaque with perforator. Structural deformation and biomechanical stress distribution after stenting were analyzed. High radial stress values were located along the stent struts, which surrounded the area with high circumferential stress. Stretched perforator orifice in a circumferential direction after stenting was simulated. These results show that structural deformation could play a role in the mechanism of perforator occlusion after Wingspan stenting.

MRI of intracranial vertebral artery dissection: evaluation of intramural haematoma using a black blood, variable-flip-angle 3D turbo spin-echo sequence.

INTRODUCTION: We investigated the efficacy of three-dimensional black blood T1-weighted imaging (3D-BB-T1WI) using a variable refocusing flip angle turbo spin-echo sequence in the diagnosis of intracranial vertebral artery dissection (VAD). METHODS: Sixteen consecutive patients diagnosed with intracranial VAD underwent magnetic resonance imaging that included 3D time-of-flight-MRA, axial spin-echo T1-weighted images (SE-T1WI) and oblique coronal 3D-BB-T1WI sequences. The visualization, morphology and extent of intramural haematomas were assessed and compared among the sequences. Results obtained by digital subtraction angiography (DSA), 3D-angiography and/or 3D-CT angiography (CTA) were used as standards of reference. RESULTS: 3D-BB-T1WI revealed intramural haematomas in all cases, whereas SE-T1WI and magnetic resonance angiography (MRA) failed to reveal a haematoma in one case and three cases, respectively. The mean visualization grading score for the intramural haematoma was the highest for 3D-BB-T1WI, and there was a statistically significant difference among the sequences (p < 0.001). At least a portion of the intramural haematoma was distinguishable from the lumen on 3D-BB-T1WI, whereas the haematomas were entirely indistinguishable from intraluminal signals on MRA in two cases (12.5%) and on SE-T1WI in one case (6.3%). 3D-BB-T1WI revealed the characteristic crescent shape of the intramural haematoma in 14 cases (87.5%), whereas SE-T1WI and MRA revealed a crescent shape in only 7 cases (43.8%) and 8 cases (50%), respectively. In a consensus reading, 3D-BB-T1WI was considered the most consistent sequence in representing the extent and morphology of the lesion in 14 cases (87.5%), compared to DSA and CTA. CONCLUSION: 3D-BB-T1WI is a promising method to evaluate intramural haematoma in patients with suspected intracranial VAD.

Onyx embolization of anterior condylar confluence dural arteriovenous fistula.

The anterior condylar confluence (ACC) is a small complex venous structure located medial to the jugular vein and adjacent to the hypoglossal canal. To our knowledge, this is the first report of transvenous Onyx embolization for ACC dural arteriovenous fistula (DAVF). Three patients with ACC DAVF were treated using the Onyx liquid embolic agent with or without detachable coils. Complete angiographic obliteration of the fistulas was achieved in all cases without permanent lower cranial neuropathy. This report suggests that the controlled penetration of Onyx is advantageous in order to obliterate ACC DAVFs with a small amount of embolic material.

Successful flow reduction treatment for a middle cerebral artery aneurysm in a patient with systemic lupus erythematosus.

A 37-year-old male with a 20-year history of systemic lupus erythematosus (SLE) was referred to our hospital for an unruptured right middle cerebral artery (MCA) aneurysm. Right cerebral angiography detected a saccular aneurysm (9.6 × 7.1 mm) arising from the bifurcation of the right MCA, and a dilatation of the inferior trunk M2 in which three small branches were involved. The MCA aneurysm was treated with neck clipping. The aneurysmal dilatation of the inferior trunk M2 was treated with proximal clipping, followed by double superficial temporal artery-MCA anastomosis. The patient was discharged from our hospital without complications. This is an extremely unusual case of surgical flow reduction treatment using bypass surgery for a complicated cerebral aneurysm in a patient with SLE.

Characterization of arterial thrombus composition by magnetic resonance imaging in a swine stroke model.

BACKGROUND AND PURPOSE: The aim of this study is to analyze the histological composition of acute arterial thrombi and their MRI signals. METHODS: Two different types of experimental thrombi, erythrocyte- and fibrin-rich thrombus, were created and injected into an experimentally formed stenotic common carotid artery in swine. MRI of the in vivo and in vitro samples was obtained immediately after the thrombus application. RESULTS: Erythrocyte component showed high on fluid-attenuated inversion recovery, and iso on T2-weighted signal in both in vitro and in vivo. Fibrin-rich thrombus was composed of fibrin/platelet and nucleated cell layers, which demonstrated iso- and low intensities, respectively, in both fluid-attenuated inversion recovery and T2-weighted images in vitro. Mixed signal was obtained in vivo. CONCLUSIONS: We successfully characterized the only erythrocyte component of acute thrombus by MRI.