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ABSTRACT: Object The authors undertook this study to assess the safety and efficacy of Onyx embolization in the treatment of intracranial arteriovenous malformations (AVMs) in pediatric patients. Methods All pediatric Onyx embolization of intracranial AVM cases performed consecutively at a single children's hospital over a 5-year period were collected and evaluated. Results Twenty-five patients (mean age 10.5 years) underwent a total of 38 procedures. An aggregate of 56 pedicles were embolized (mean 1.47 per session). The Spetzler-Martin grade was determined in all cases. Onyx embolization resulted in complete obliteration of the AVM in 3 cases (12%) and partial obliteration in 22 cases (88%). A total of 23 patients underwent surgical treatment. The mean preoperative AVM devascularization in these cases was 72%. One patient was treated with radiosurgery following Onyx embolization. Overall, 10 complications occurred in a total of 38 procedures (26.3%). None of the complications resulted in permanent neurological morbidity. The rate of transient neurological complications was 10.5% (4 of 38 procedures) and the rate of transient nonneurological complications was 5.3% (2 of 38 procedures). The remaining 4 complications were clinically silent (rate of 10.5%). There were no procedure-related deaths in this study population. There was no significant difference in patients with and without complications in terms of demographic characteristics, AVM grade, or embolization features (p ≥ 0.2). Deep venous drainage was associated with higher complication rates (p = 0.03). Conclusions Onyx utilization is feasible for preoperative or primary embolization in the treatment of pediatric intracranial AVMs; however, the spectrum of complications encountered is broad, and attention must be paid to the technical nuances of and indications for its use to avoid many potential dangerous effects. Although the overall complication rates were higher than expected, all were either clinically silent or had only transient clinical effects. Thus, this experience suggests that Onyx embolization can be performed safely with a low rate of permanent morbidity in pediatric patients harboring these difficult lesions.
Journal of Neurosurgery Pediatrics 02/2013; · 1.53 Impact Factor
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ABSTRACT: BACKGROUND: Spinal artery aneurysms associated with aortic coarctation are exceptionally rare, with only eight cases reported in the literature that we are aware of, and treatment of the aneurysm described only in one of them. Aortic coarctation often results in an aberrant collateral circulation with hyperdynamic flow and potential spinal artery aneurysm formation, growth, and rupture. Microsurgical, interventional, and medical management of these lesions can be challenging and has rarely been reported. Complication avoidance requires thorough knowledge of the clinical presentation of the disease, the hemodynamic factors involved, and the therapeutic tools available. CASE DESCRIPTION: A 59-year-old woman with a previously undiagnosed isthmic coarctation of the aorta presented with subarachnoid hemorrhage. A 7-mm wide-necked, saccular spinal artery aneurysm was identified as the source of the hemorrhage and was subsequently successfully coiled through a transbrachial access route. After rehabilitation, the patient returned to her asymptomatic neurologic baseline, and underwent successful surgical repair of the aortic coarctation with placement of an interposition graft. CONCLUSIONS: Spinal artery aneurysms induced by aortic coarctation are rare and complex entities. They pose unique surgical and medical challenges. Securing the aneurysm should be prioritized specifically in cases of subarachnoid hemorrhage. Blood pressure should be closely monitored and balanced to reduce the risk of rehemorrhage and at the same time allow for sufficient end-organ perfusion.
World Neurosurgery 08/2012; · 0.68 Impact Factor
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ABSTRACT: Carotid body paragangliomas are rare hypervascular lesions which may benefit from preoperative devascularization to reduce intraoperative blood loss. The optimal method for devascularization of these tumors is not known. Our purpose was to evaluate the extent of angiographic devascularization and intraoperative blood loss using only ethylene vinyl alcohol copolymer (EVOH) for percutaneous glomus tumor embolization.
A consecutive series of seven paragangliomas located at the carotid bifurcation were treated with percutaneous embolization with EVOH as the sole embolic agent.
Complete devascularization of seven paragangliomas was achieved in all cases percutaneously with only EVOH. There were no complications. The average intraoperative blood loss was 55 ml (range 15-80 ml).
Our preliminary experience suggests that EVOH may offer a higher degree of devascularization when compared with other embolic agents. This may facilitate easier surgical resection with lower blood loss. EVOH seems to be safe when percutaneously injected as the sole embolic agent.
Journal of neurointerventional surgery 03/2012; 4(2):125-9. · 0.92 Impact Factor
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ABSTRACT: To increase the in-plane spatial resolution and image update rates of 2D magnetic resonance (MR) digital subtraction angiography (DSA) pulse sequences to 0.57 × 0.57 mm and 6 frames/sec, respectively, for intracranial vascular disease applications by developing a radial FLASH protocol and to characterize a new artifact, not previously described in the literature, which arises in the presence of such pulse sequences.
The pulse sequence was optimized and artifacts were characterized using simulation and phantom studies. With Institutional Review Board (IRB) approval, the pulse sequence was used to acquire time-resolved images from healthy human volunteers and patients with x-ray DSA-confirmed intracranial vascular disease.
Artifacts were shown to derive from inhomogeneous spoiling due to the nature of radial waveforms. Gradient spoiling strategies were proposed to eliminate the observed artifact by balancing gradient moments across TR intervals. The resulting radial 2D MR DSA sequence (2.6 sec temporal footprint, 6 frames/sec with sliding window factor 16, 0.57 × 0.57 mm in-plane) demonstrated small vessel detail and corroborated x-ray DSA findings in intracranial vascular imaging studies.
Appropriate gradient spoiling in radial 2D MR DSA pulse sequences improves intracranial vascular depiction by eliminating circular banding artifacts. The proposed pulse sequence may provide a useful addition to clinically applied 2D MR DSA scans.
Journal of Magnetic Resonance Imaging 02/2012; 36(1):249-58. · 2.70 Impact Factor
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Journal of Cardiovascular Magnetic Resonance 02/2012; 14 Suppl 1:W2. · 3.72 Impact Factor
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ABSTRACT: The singular value decomposition deconvolution of cerebral tissue concentration–time curves with the arterial input function is commonly used in dynamic susceptibility contrast cerebral perfusion MR imaging. However, it is sensitive to the time discrepancy between the arrival of the bolus in the tissue concentration–time curve and the arterial input function signal. This normally causes inaccuracy in the quantitative perfusion maps due to delay and dispersion effects. A comprehensive correction algorithm has been achieved through slice-dependent time-shifting of the arterial input function, and a delay-dependent dispersion correction model. The correction algorithm was tested in 11 healthy subjects and three ischemic stroke patients scanned with a quantitative perfusion pulse sequence at 1.5 T. A validation study was performed on five patients with confirmed cerebrovascular occlusive disease scanned with MRI and positron emission tomography at 3.0 T. A significant effect (P < 0.05) was reported on the quantitative cerebral blood flow and mean transit time measurements (up to 50%). There was no statistically significant effect on the quantitative cerebral blood volume values. The in vivo results were in agreement with the simulation results, as well as previous literature. This minimizes the bias in patient diagnosis due to the existing errors and artifacts in dynamic susceptibility contrast imaging. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc.
Magnetic Resonance in Medicine 12/2011; · 2.96 Impact Factor
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World Neurosurgery 11/2011; 77(5-6):659-61. · 0.68 Impact Factor
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ABSTRACT: BACKGROUND: A combined imaging suite is useful in the diagnosis and treatment of vascular disease involving the head and neck. This study demonstrates the utility of a multidetector row CT and biplane digital subtraction angiography (DSA) system (hybrid suite) with a single interactive table for the evaluation and treatment of neurovascular disease. METHODS: 30 patients were studied utilizing the hybrid suite. Direct intra-arterial and selective intravenous injection of contrast with CT imaging (IA-CTA and IV-CTV) was performed in nine vascular tumors, three intracranial arteriovenous malformations, four spinal vascular lesions, one aneurysm and two inferior petrosal sinus sampling cases. Angiography with CT perfusion (CTP) imaging was obtained in five temporary balloon occlusion tests, two ischemic stroke and two vasospasm cases. A CT scan of the head was obtained in two cases during aneurysm coiling. The value of the IA-CTA and IV-CTV images compared with conventional CT and MRI images was qualitatively assessed. RESULTS: All studies were technically successful with no complications. IA-CTA and IV-CTV were useful in the diagnosis and treatment of vascular disease. All IA-CTA and IV-CTV images were qualitatively graded as superior to conventional imaging. CTP imaging provided information about the penumbra and area of infarction in five temporary balloon test occlusions, two ischemic stroke and two vasospasm cases. A CT scan of the head provided timely information in two aneurysm coiling cases. The hybrid suite allowed angiography and CT scanning to be performed immediately without patient transfer. CONCLUSION: This hybrid suite improves the diagnostic and therapeutic capabilities of treating a multitude of neurovascular diseases.
Journal of neurointerventional surgery 09/2011; · 0.92 Impact Factor
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ABSTRACT: Reversible cerebral vasoconstriction syndromes (RCVS) represent a heterogeneous group of cerebrovascular disease characterized by acute presentations and transient segmental narrowing of the distal intracranial arteries. A series of patients with RCVS were studied to better understand the clinical and imaging characteristics of this rare pathology.
A retrospective study was performed on patients that met inclusion criteria for a diagnosis of RCVS. Pertinent clinical and laboratory data, initial and follow-up imaging, treatment and outcomes were studied.
11 patients (10 women, mean age 42 years) diagnosed with RCVS presented with acute onset of severe headache, neurological symptoms and subarachnoid hemorrhage (SAH). Cross sectional imaging (CT/MRI) identified presentations of cortical SAH (n=9) and/or acute infarcts (n=3). Initial cerebral angiography (digital subtraction angiography n=10 or MR angiography n=1) confirmed diffuse vasoconstriction involving the intracranial vasculature. Rheumatological panel (n=9) and CSF analysis (n=8) were not supportive of vasculitis in any patient. In nearly all cases, reversal of vasoconstriction was noted on follow-up cerebral angiography with early resolution in less than 3 months.
RCVS classically presents with 'thunderclap' headaches and neurological symptoms but cortical SAH is not an uncommon presentation with a unique and focal distribution overlying the cerebral sulci. Although the initial clinical and angiographic appearance of RCVS may be confused for vasospasm related to aneurysmal SAH or primary angiitis of the CNS, its clinical, laboratory and imaging features assist in diagnosis.
Journal of neurointerventional surgery 09/2011; 3(3):272-8. · 0.92 Impact Factor
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ABSTRACT: Cerebrovascular complications related to cocaine abuse are reaching epidemic proportions. Contemporary treatments for acute stroke have made it essential to gather all possible diagnostic information before proceeding with intervention. We describe a cocaine abuser who presented with acute right sided neurological deficits and deteriorating mental status. An MRI demonstrated right sided acute and chronic infarcts in the border zones of the right anterior cerebral arteries (ACA) and middle cerebral arteries (MCAs). Subsequent CT angiography (CTA)/CT perfusion (CTP) identified multifocal cerebral vasospasm of the bilateral ACAs and MCAs, preserved cerebral blood volume (CBV) and decreased cerebral blood flow (CBF) in bilateral frontoparietal regions. Early diagnosis of multifocal vasospasm related ischemia directed appropriate therapy and excluded thrombolytic intervention. After 3 weeks, patient's presenting symptoms gradually resolved. We report a unique case of cocaine induced multifocal vasospasm exhibiting late (>3 weeks) reversibility of focal neurological deficits. Furthermore, we illustrate the benefits of CTA/CTP imaging in the setting of cocaine abuse, differentiating multifocal vasospasm induced hypoperfusion/ischemia from focal thromboembolic ischemia/infarct and allowing for appropriate medical management in the crucial hyperacute setting.
Journal of stroke and cerebrovascular diseases: the official journal of National Stroke Association 06/2011;
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ABSTRACT: To describe our experience with very distal placement of the Neuron 6 F 0.053 inch inner luminal diameter guide catheter (Penumbra Inc, San Leandro, California, USA) within the intracranial and extracranial vasculature to allow treatment of various neurovascular pathologies. Previously, this was thought to be only possible with a microcatheter.
12 cases are presented in which traditional guide catheters were unable to successfully navigate tortuous anatomy or provide stable support for intervention.
The Neuron 6 F 0.053 inch inner luminal diameter delivery catheter (Penumbra) was placed in a very distal location within the internal carotid artery, external carotid artery and venous system enabling successful endovascular treatment of the intracranial pathology with no related neurological complications.
All lesions were successfully treated through a microcatheter advanced in a coaxial fashion through the distally placed guide catheter. There were no complications related to the distal position of the guide catheter.
Journal of neurointerventional surgery 06/2011; 4(4):301-6. · 0.92 Impact Factor
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ABSTRACT: A mandibular arteriovenous malformation (AVM) presented with massive molar socket bleeding and was emergently treated by tooth extraction and partial resection of the surrounding alveolar bone. To achieve hemostasis, the resultant cavity was filled with hydroxyapatite bone cement. Not only was hemostasis and alveolar reconstruction achieved, but follow-up angiography demonstrated venous outlet occlusion and retrograde AVM thrombosis requiring no further treatment.
Journal of neurointerventional surgery 03/2011; 3(1):92-4. · 0.92 Impact Factor
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ABSTRACT: Bioactive polyglycolic/polylactic acid (PGLA)-coated Matrix detachable coils were reported to incite intra-aneurysmal inflammation and fibrosis. Multiple large case series with Matrix-1 coils have shown no advantage with respect to aneurysm recurrence. Second-generation Matrix-2 coils were designed with improved platinum support and reduced copolymer friction. We assessed the safety and efficacy of Matrix-2 coil embolization.
84 aneurysms were embolized primarily with Matrix-2 coils. Anatomic results were evaluated using a modified Raymond scale with progressive occlusion or recanalization/recurrence strictly defined as any interval change in intra-aneurysmal opacification.
Mid-term (8.9±3.4 months) and long-term (23.0±7.4 months) follow-up was available for 65 aneurysms. At mid-term, 55 (85%) aneurysms remained stable (or progressed to occlusion) versus 10 (15%) recurrent aneurysms, 7 (11%) requiring retreatment. At long term, 49 (75%) aneurysms remained stable versus 16 (25%) recurrent aneurysms, 12 (18%) requiring retreatment. Statistically significant factors affecting recanalization included ruptured aneurysms 9/20 (45%), large aneurysms 5/8 (71%), post-procedure residual aneurysms 6/12 (50%) and differential coil packing density of recurrent (21%) versus stable (28%) aneurysms. Patient morbidity (5%) was limited to thromboembolic complications (n=4) or aneurysm rerupture (n=1). Patient mortality (5%) was secondary to subarachnoid hemorrhage complications (n=4) with no procedure-related deaths (0%).
Coil embolization with Matrix-2 coils is safe and effective, preventing recanalization in small aneurysms at mid-term. Although these aneurysm recurrence rates initially appeared lower than previous reports with Matrix-1 or platinum coils, significant late recanalization was observed on long-term follow-up. We postulate that any derived benefit from Matrix-2 coils is directly dependent on post-procedure outcomes and coil packing density.
Journal of neurointerventional surgery 02/2011; 3(4):324-30. · 0.92 Impact Factor
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Journal of vascular and interventional radiology: JVIR 03/2010; 21(3):406-9. · 1.81 Impact Factor
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ABSTRACT: Isolated third cranial nerve palsies may be caused by compressive intracranial aneurysms located at the junction of the internal carotid and posterior communicating arteries or, less commonly, at the apex of the basilar artery or its junction with the superior cerebellar or posterior cerebral arteries. Such aneurysms typically measure at least 4 mm in diameter. Technical improvements in noninvasive techniques, including CT and MRA, have yielded a detection rate of such aneurysms that approaches that of catheter cerebral angiography (CCA), which itself carries a small but serious risk. Multidetector technology, which allows a rapid scan time, has promoted CT to the first choice for investigating aneurysms in this setting except when dye or radiation exposure is unacceptable, as with pregnant women, children, and those with renal or severe cardiac disease. Major impediments to accurate detection are a lack of availability of trained technicians, who must perform manipulation of the raw imaging data ("post-processing"), and a paucity of certified neuroradiologists with the time, skill, and experience to devote to interpreting difficult cases. To avoid diagnostic mishaps, noninvasive studies should be reviewed by at least one neuroradiologist before aneurysm is rejected as the cause or before the patient undergoes CCA.
Journal of neuro-ophthalmology: the official journal of the North American Neuro-Ophthalmology Society 10/2009; 29(3):238-44. · 1.09 Impact Factor
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ABSTRACT: Carotid cavernous fistulas (CCFs) are abnormal communications between the carotid arterial system and the cavernous sinus. CCFs are broadly classified as either direct or indirect. Surgical treatment of CCFs is technically difficult and is associated with significant morbidity. Endovascular techniques from either an arterial or a venous approach have become the mainstay of treatment given the recent advances in endovascular technology. This article provides an overview of various endovascular approaches available for the treatment of CCFs.
Neuroimaging Clinics of North America 06/2009; 19(2):241-55, Table of Contents. · 1.51 Impact Factor
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ABSTRACT: Juvenile nasopharyngeal angiofibromas and paragangliomas are the most common hypervascular tumors of the head and neck that require embolization as an adjunct to surgery. A detailed understanding of the functional vascular anatomy of the external carotid artery is necessary for safe and effective endovascular therapy. Embolization, using a transarterial technique and particulate agents, a direct puncture technique and liquid embolic agents, or both techniques may allow for complete devascularization of hypervascular tumors of the head and neck. Effective embolization of these tumors results in a significant reduction of blood loss during surgery and allows for complete resection of the tumors. Use of meticulous technique and a thorough knowledge of functional anatomy of the head and neck vasculature are essential.
Neuroimaging Clinics of North America 06/2009; 19(2):181-98, Table of Contents. · 1.51 Impact Factor
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ABSTRACT: Cervical arterial dissections and dissecting aneurysms are relatively rare pathologies, but can be associated with significant morbidity from ischemic complications. We review the challenges in diagnosing cervical arterial dissections, their unique clinical presentations and imaging characteristics. Although the majority of cervical dissections heal spontaneously with medical management, we discuss the specific indications for surgical or endovascular treatment to prevent thromboembolic complications. Furthermore, we provide a detailed technical review on endovascular stent reconstruction, the primary interventional option for symptomatic cervical dissections and dissecting aneurysms refractory to medical management.
Neuroimaging Clinics of North America 06/2009; 19(2):257-70, Table of Contents. · 1.51 Impact Factor
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ABSTRACT: Recent technologic advances including multidetector CT, dynamic CT angiography, high-field MR imaging, four-dimensional MR angiography, and physiologic studies, such as perfusion imaging, have revolutionized the imaging work-up of head, neck, and skull base lesions. These techniques not only provide accurate diagnostic information, but also help plan endovascular therapy. The future holds great promise for interventional neuroradiologists because excellent imaging tools are becoming available that are capable of providing morphologic, hemodynamic, and physiologic information. Furthermore, availability of faster, real-time guidance systems and hybrid systems improves the ability to perform procedures not only in a rapid and safe manner but also with great precision.
Neuroimaging Clinics of North America 06/2009; 19(2):133-47, Table of Contents. · 1.51 Impact Factor
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ABSTRACT: Carotid-cavernous fistulas (CCFs) are abnormal arteriovenous communications in the cavernous sinus. Direct CCFs result from a tear in the intracavernous carotid artery. Indirect CCFs generally occur spontaneously and cause more subtle signs. Direct CCFs, which typically have high flow, usually present with ocular-orbital venous congestive features and cephalic bruit. Indirect CCFs, which typically have low flow, present with similar but more muted clinical features. Direct CCFs are always treated with endovascular methods. The goal is to occlude the fistula but preserve the patency of the internal carotid artery (ICA). Agents include detachable coils or liquid embolic agents delivered transarterially or transvenously. Arterial porous or covered stents are often used adjunctively. In rare cases, the ICA must be occluded. Indirect CCFs are only treated if symptoms are intractable or intolerable or if vision is threatened. The goal is to interrupt the fistulous communications and decrease the pressure in the cavernous sinus. The traditional approach has been transarterial embolization with liquid agents, particularly n-butyl cyanoacrylate (n-BCA). However, the multiplicity of arterial feeders and the low success rate in occluding indirect CCFs by the arterial route has led to a preference for transvenous embolization, most commonly via the inferior petrosal sinus. If that sinus is impassable, alternative routes include the pterygoid venous plexus, superior petrosal sinus, facial vein, or ophthalmic veins. The cavernous sinus is occluded with coils, liquid embolic agents, or both. The use of ethylene vinyl alcohol copolymer (Onyx), an agent that may be superior to n-BCA because it may allow better distal fistula penetration. However, more safety and efficacy data must be accumulated. When experienced interventionalists are involved, the success rate for closing direct fistulas is 85%-99% and for closing indirect fistulas is 70%-78%. Serious complications are relatively infrequent.
Journal of neuro-ophthalmology: the official journal of the North American Neuro-Ophthalmology Society 04/2009; 29(1):62-71. · 1.09 Impact Factor
