A matched-pair case control study identifying hemodynamic predictors of cerebral aneurysm growth using computational fluid dynamics.

Initiation and progression of cerebral aneurysms is known to be driven by complex interactions between biological and hemodynamic factors, but the hemodynamic mechanism which drives aneurysm growth is unclear. We employed robust modeling and computational methods, including temporal and spatial convergence studies, to study hemodynamic characteristics of cerebral aneurysms and identify differences in these characteristics between growing and stable aneurysms. Eleven pairs of growing and non-growing cerebral aneurysms, matched in both size and location, were modeled from MRA and CTA images, then simulated using computational fluid dynamics (CFD).

Matched-pair analysis of patients with ischemic stroke undergoing thrombectomy using next-generation balloon guide catheters.

Background: Balloon guide catheters (BGCs) have not been widely adopted, possibly due to the incompatibility of past-generation BGCs with large-bore intermediate catheters. The next-generation BGC is compatible with large-bore catheters. We compared outcomes of thrombectomy cases using BGCs versus conventional guide catheters.

A case of recurrent aneurysm resulting from dual antiplatelet plus anticoagulation after confirmed aneurysm closure following coil-assisted flow diversion.

Dual antiplatelet therapy (DAPT) is a management cornerstone for intracranial aneurysms treated with flow diversion. However, combined dual antiplatelet plus anticoagulation (triple therapy) can be indicated in some patients with important associated risks. Here we present the case of a 72-year-old woman with prior history of subarachnoid hemorrhage who was started on triple therapy (enoxaparin and DAPT) following successful flow diversion of an enlarging but unruptured left fetal posterior communicating artery aneurysm.

Comparison of embolization strategies for mixed plexiform and fistulous brain arteriovenous malformations: a computational model analysis of theoretical risks of nidus rupture.

Background: High-flow fistulas related to plexiform nidi are found in 40% of large brain arteriovenous malformations (AVMs). Endovascular occlusion of intranidal fistulas before plexiform components is empirically considered safe, but potential ensuing dangerous re-routing of flow through plexiform vessels may in theory raise their rupture risk. It remains unclear whether it is safer to embolize plexiform or fistulous vessels initially.

Efficacy and safety of embolization of dural arteriovenous fistulas via the ophthalmic artery.

Introduction: Dural arteriovenous fistulae (DAVF) are vascular lesions with arteriovenous shunting that may be treated with surgical obliteration or endovascular embolization. Some DAVF, such as anterior cranial fossa DAVF (AC-DAVF) derive their arterial supply from ophthalmic artery branches in nearly all cases, and trans-arterial embolization carries a risk of vision loss. We determined the efficacy and safety of trans-ophthalmic artery embolization of DAVF.

Dual antiplatelet therapy after carotid artery stenting: trends and outcomes in a large national database.

Background: While dual antiplatelet therapy (dAPT) is standard of care following carotid artery stenting (CAS), the optimal dAPT regimen and duration has not been established.

Methods: We canvassed a large national database (IBM MarketScan) to identify patients receiving carotid endarterectomy (CEA) or CAS for treatment of ischemic stroke or carotid artery stenosis from 2007 to 2016. We performed univariable and multivariable regression methods to evaluate the impact of covariates on post-CAS stroke-free survival, including post-discharge antiplatelet therapy.

Tortuosity of superior cerebral veins: Comparative magnetic resonance imaging morphometrics in normal subjects and arteriovenous malformation patients.

Blood vessel tortuosity results from increased diameter and length in response to higher hemodynamic loads. Tortuosity metrics have not been determined for abnormal superior cerebral veins (SCVs) draining cerebral arteriovenous malformations (AVMs). Draining vein (DV) tortuosity may influence safety and efficacy of retrograde microcatheter navigation during transvenous treatment of pial AVMs.

Three-Dimensional Angles of Confluence of Cortical Bridging Veins and the Superior Sagittal Sinus on MR Venography: Does Drainage of Adjacent Brain Arteriovenous Malformations Alter this Spatial Configuration?

Few neuroimaging anatomic studies to date have investigated in detail the point of entry of cortical bridging veins (CBVs) into the superior sagittal sinus (SSS). Although we know that most CBVs join the SSS at an acute angle opposite to the direction of SSS blood flow, the three-dimensional (3-D) spatial configuration of these venous confluences has not been studied previously. This anatomical information would be pertinent to several clinically applicable scenarios, such as in planning intracranial surgical approaches that preserve bridging veins; studying anatomical factors in the pathophysiology of SSS thrombosis; and when planning endovascular microcatheterization of pial veins to retrogradely embolize brain arteriovenous malformations (AVMs).

Early Cerebral Vein After Endovascular Ischemic Stroke Treatment Predicts Symptomatic Reperfusion Hemorrhage.

Background And Purpose: Parenchymal hemorrhage (PH) after endovascular mechanical thrombectomy in acute ischemic stroke leads to worse outcomes. Better clinical and imaging biomarkers of symptomatic reperfusion PH are needed to identify patients at risk. We identified clinical and imaging predictors of reperfusion PH after endovascular mechanical thrombectomy with attention to early cerebral veins (ECVs) on postreperfusion digital subtraction angiography.

Clinical and Arterial Spin Labeling Brain MRI Features of Transitional Venous Anomalies.

Background And Purpose: Transitional venous anomalies (TVAs) are rare cerebrovascular lesions that resemble developmental venous anomalies (DVAs), but demonstrate early arteriovenous shunting on digital subtraction angiography (DSA) without the parenchymal nidus of arteriovenous malformations (AVMs). We investigate whether arterial spin labeling (ASL) magnetic resonance imaging (MRI) can distinguish brain TVAs from DVAs and guide their clinical management.

Methods: We conducted a single-center retrospective review of patients with brain parenchymal DVA-like lesions with increased ASL signal on MRI.

Sofia intermediate catheter and the SNAKE technique: safety and efficacy of the Sofia catheter without guidewire or microcatheter construct.

Background: Neurointerventional surgeries (NIS) benefit from supportive endovascular constructs. Sofia is a soft-tipped, flexible, braided single lumen intermediate catheter designed for NIS. Sofia advancement from the cervical to the intracranial circulation without a luminal guidewire or microcatheter construct has not been described.

Pipeline embolization device retraction and foreshortening after internal carotid artery blister aneurysm treatment.

Background Subarachnoid hemorrhage (SAH) secondary to rupture of a blister aneurysm (BA) results in high morbidity and mortality. Endovascular treatment with the pipeline embolization device (PED) has been described as a new treatment strategy for these lesions. We present the first reported case of PED retraction and foreshortening after treatment of a ruptured internal carotid artery (ICA) BA.

Fluoroscopic C-Arm and CT-Guided Selective Radiofrequency Ablation for Trigeminal and Glossopharyngeal Facial Pain Syndromes.

Objectives: Percutaneous radiofrequency ablation (RFA) of the gasserian ganglion through the foramen ovale and the glossopharyngeal nerve at the jugular foramen is a classical approach to treating trigeminal neuralgia (TN) and glossopharyngeal neuralgia (GPN), respectively. However, it can be technically challenging with serious complications. We have thus developed a novel technique utilizing C-arm and computerized tomography (CT) guidance to block TN and GPN.

Initial experience with SOFIA as an intermediate catheter in mechanical thrombectomy for acute ischemic stroke.

Background: The benefits of mechanical thrombectomy for emergent large vessel occlusion (ELVO) have been established. Combined mechanical/aspiration (Solumbra) and a direct aspiration as a first pass technique (ADAPT) are valid procedures requiring an intermediate catheter for clot suction. Recently, SOFIA (Soft torqueable catheter Optimized For Intracranial Access) was developed as a single lumen flexible catheter with coil and braid reinforcement, but its suitability for mechanical thrombectomy had not been evaluated.

Headway Duo microcatheter for cerebral arteriovenous malformation embolization with n-BCA.

Background: Cerebral arteriovenous malformations (AVMs) are uncommon vascular lesions, and hemorrhage secondary to AVM rupture results in significant morbidity and mortality. AVMs may be treated by endovascular embolization, and technical advances in microcatheter design are likely to improve the success and safety of endovascular embolization of cerebral AVMs.

Objective: To describe our early experience with the Headway Duo microcatheter for embolization of cerebral AVMs with n-butyl-cyanoacrylate (n-BCA).

Cerebral vascular findings in PAPA syndrome: cerebral arterial vasculopathy or vasculitis and a posterior cerebral artery dissecting aneurysm.

A young patient with PAPA (pyogenic arthritis, pyoderma gangrenosum, and acne) syndrome developed an unusual cerebral arterial vasculopathy/vasculitis (CAV) that resulted in subarachnoid hemorrhage from a ruptured dissecting posterior cerebral artery (PCA) aneurysm. This aneurysm was successfully treated by endovascular coil sacrifice of the affected segment of the PCA. The patient made an excellent recovery with no significant residual neurologic deficit.

Cerebral vascular findings in PAPA syndrome: cerebral arterial vasculopathy or vasculitis and a posterior cerebral artery dissecting aneurysm.

A young patient with PAPA (pyogenic arthritis, pyoderma gangrenosum, and acne) syndrome developed an unusual cerebral arterial vasculopathy/vasculitis (CAV) that resulted in subarachnoid hemorrhage from a ruptured dissecting posterior cerebral artery (PCA) aneurysm. This aneurysm was successfully treated by endovascular coil sacrifice of the affected segment of the PCA. The patient made an excellent recovery with no significant residual neurologic deficit.

Arterial spin labeling MRI: clinical applications in the brain.

Visualization of cerebral blood flow (CBF) has become an important part of neuroimaging for a wide range of diseases. Arterial spin labeling (ASL) perfusion magnetic resonance imaging (MRI) sequences are increasingly being used to provide MR-based CBF quantification without the need for contrast administration, and can be obtained in conjunction with a structural MRI study. ASL MRI is useful for evaluating cerebrovascular disease including arterio-occlusive disease, vascular shunts, for assessing primary and secondary malignancy, and as a biomarker for neuronal metabolism in other disorders such as seizures and neurodegeneration.

Cysts and cystic-appearing lesions of the knee: A pictorial essay.

Cysts and cystic-appearing lesions around the knee are common and can be divided into true cysts (synovial cysts, bursae, ganglia, and meniscal cysts) and lesions that mimic cysts (hematomas, seromas, abscesses, vascular lesions, and neoplasms). The specific anatomic location of the cystic lesion often permits the correct diagnosis. In difficult cases, identifying a cystic mass in an atypical location and/or visualizing internal solid contrast enhancement on magnetic resonance imaging (MRI) should raise concern for a neoplasm and the need for further evaluation and intervention.

Analysis of venous drainage in three patients with extradural spinal arteriovenous fistulae at the craniovertebral junction with potentially benign implication.

Background: Extradural arteriovenous fistulae (AVFs) are vascular malformations that result from a direct connection between an extradural artery and vein, resulting in a high flow fistula that drains into the epidural venous system. Extradural AVFs may cause myelopathy when distended epidural veins compress the cord or when venous hypertension causes venous stasis within the spinal cord, and are uncommon causes of subarachnoid hemorrhage (SAH), although the presence of intracranial drainage is a risk factor for SAH. There are numerous reports of SAH and AVF with rostral intracranial venous drainage, implying an intradural drainage pathway.

MRI of adnexal masses in pregnancy.

Objective: The objective of this article is to provide a practical review of the incremental benefit of MRI in the assessment of adnexal masses in pregnancy.

Conclusion: MRI can assist sonographic assessment of adnexal masses in pregnancy by depicting the characteristic findings of exophytic leiomyoma, red degeneration of leiomyoma, endometrioma, decidualized endometrioma, and massive ovarian edema. Accordingly, MRI should be considered as a useful adjunct when sonography is inconclusive or insufficient to guide management of adnexal masses discovered in pregnancy.