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Leonardo Rangel-Castilla, Chandan Krishna, Richard Klucznik and Orlando Diaz

Sinus pericranii (SP) is an uncommon and usually asymptomatic communication between intra- and extracranial venous drainage pathways in which blood flow can circulate bidirectionally through abnormal dilated veins through a skull defect. Diagnosis and evaluation of the venous drainage pattern is important if treatment is contemplated. Cerebral angiography with the use of Dyna CT can be helpful in the diagnosis of SP and its relationship with the skull defect. The authors report what is, to the best of their knowledge, the first case of SP treated by means of endovascular embolization with Onyx.

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Leonardo Rangel-Castilla, Paul J. Holman, Chandan Krishna, Todd W. Trask, Richard P. Klucznik and Orlando M. Diaz


Spinal extradural (epidural) arteriovenous fistulas (AVFs) are uncommon vascular lesions of the spine with arteriovenous shunting located primarily in the epidural venous plexus. Understanding the complex anatomical variations of these uncommon lesions is important for management. The authors describe the different types of spinal extradural AVFs and their endovascular management using Onyx.


Eight spinal extradural AVFs in 7 patients were studied using MR imaging, spinal angiography, and dynamic CT (DynaCT) between 2005 and 2009. Special consideration was given to the anatomy, pattern of venous drainage, and mass effect upon the nerve roots, spinal cord, and vertebrae.


The neuroaxial location of the 8 spinal extradural AVFs was lumbosacral in 1 patient, lumbar in 4 patients, thoracic in 2 patients, and cervical in 1 patient. Spinal extradural AVFs were divided into 3 types. In Type A spinal extradural AVFs, arteriovenous shunting occurs in the epidural space and these types have an intradural draining vein causing venous hypertension and spinal cord edema with associated myelopathy or cauda equina syndrome. Type B1 malformations are confined to the epidural space with no intradural draining vein, causing compression of the spinal cord and/or nerve roots with myelopathy and/or radiculopathy. Type B2 malformations are also confined to the epidural space with no intradural draining vein and no mass effect, and are asymptomatic. There were 4 Type A spinal extradural AVFs, 3 Type B1s, and 1 Type B2. Onyx was used in all cases for embolization. Follow-up at 6–24 months showed that 4 patients experienced excellent recovery. Three patients with Type A spinal extradural AVFs attained good motor recovery but experienced persistent bladder and/or bowel problems.


The current description of the different types of spinal extradural AVFs can help in understanding their pathophysiology and guide management. DynaCT was found to be useful in understanding the complex anatomy of these lesions. Endovascular treatment with Onyx is a good alternative for spinal extradural AVF management.

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Leonardo Rangel-Castilla, Stephan A. Munich, Naser Jaleel, Marshall C. Cress, Chandan Krishna, Ashish Sonig, Kenneth V. Snyder, Adnan H. Siddiqui and Elad I. Levy


The Pipeline Embolization Device (PED) has become increasingly used for the treatment of intracranial aneurysms. Given its high metal surface area coverage, there is concern for the patency of branch vessels that become covered by the device. Limited data exist regarding the patency of branch vessels adjacent to aneurysms that are covered by PEDs. The authors assessed the rate of intracranial internal carotid artery, anterior circulation branch vessel patency following PED placement at their institution.


The authors retrospectively reviewed the records of 82 patients who underwent PED treatment between 2009 and 2014 and in whom the PED was identified to cover branch vessels. Patency of the anterior cerebral, posterior communicating, anterior choroidal, and ophthalmic arteries was evaluated using digital subtraction angiography preoperatively and postoperatively after PED deployment and at longer-term follow-up.


Of the 127 arterial branches covered by PEDs, there were no immediate postoperative occlusions. At angiographic follow-up (mean 10 months, range 3–34.7 months), arterial side branches were occluded in 13 (15.8%) of 82 aneurysm cases and included 2 anterior cerebral arteries, 8 ophthalmic arteries, and 3 posterior communicating arteries. No cases of anterior choroidal artery occlusion were observed. Patients with branch occlusion did not experience any neurological symptoms.


In this large series, the longer-term rate of radiographic side branch arterial occlusion after coverage by a flow diverter was 15.8%. Terminal branch vessels, such as the anterior choroidal artery, remained patent in this series. The authors' series suggests that branch vessel occlusions are clinically silent and should not deter aneurysm treatment with flow diversion.

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Ashish Sonig, Ning Lin, Chandan Krishna, Sabareesh K. Natarajan, Maxim Mokin, L. Nelson Hopkins, Kenneth V. Snyder, Elad I. Levy and Adnan H. Siddiqui


In this study, the authors used information provided in the Nationwide Inpatient Sample (NIS) to study the impact of transferring stroke patients from one facility to a center where they received some form of active stroke intervention (intravenous tissue plasminogen activator, thrombectomy, or a combination of both therapies).


Patient demographic characteristics and hospital factors obtained from the 2008–2010 acute stroke NIS data were analyzed. Discharge disposition, hospitalization cost, and mortality were the dependent variables studied. Univariate analysis and multivariate binary logistic regression analysis were performed. Data analysis focused on the cohort of acute stroke patients who received some form of active intervention (55,913 of 1,311,511 patients in the NIS).


When overall outcome was considered, transferred patients had a significantly higher number of other-than-routine (OTR, i.e., other than discharge to home without home health care) discharge dispositions (p < 0.0001). In multivariate regression analysis including pertinent patient and hospital factors, transfer-in patients had significantly worse OTR discharge disposition (p < 0.0001, odds ratio [OR] 2.575, 95% CI 2.341–2.832). Mean hospitalization cost including an intervention was $70,325.11 for direct admissions and $97,546.92 for transferred patients. Transfer from another facility (p < 0.001, OR 1.677, 95% CI 1.548–1.817) was associated with higher hospitalization cost.


The study showed that hospital cost for acute stroke intervention is significantly higher for a transferred patient than for a direct admission. Moreover, the frequency of OTR discharge was significantly higher among transferred patients than direct admissions. Future strategies should focus on ways and means of transporting patients appropriately and directly to stroke centers.