Koichiro Takemoto, Satoshi Tateshima, Sachin Rastogi, Nestor Gonzalez, Reza Jahan, Gary Duckwiler, Fernando Vinuela[show abstract] [hide abstract]
ABSTRACT: 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.Case Reports 01/2013; 2013.
Article: Disappearance of a small intracranial aneurysm as a result of vessel straightening and in-stent stenosis following use of an Enterprise vascular reconstruction device.Koichiro Takemoto, Satoshi Tateshima, Sachin Rastogi, Nestor Gonzalez, Reza Jahan, Gary Duckwiler, Fernando Vinuela[show abstract] [hide abstract]
ABSTRACT: 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.Case Reports 01/2013; 2013(jan16_1).
Article: Endovascular treatment of ruptured dissecting aneurysms of the posterior inferior cerebellar artery.[show abstract] [hide abstract]
ABSTRACT: BACKGROUND: Dissecting aneurysms of the posterior inferior cerebellar artery (PICA) are rare, with optimal treatment strategies not well established according to the location of the aneurysm on the PICA. We present our single-center experience of endovascular treatment of ruptured dissecting aneurysms of the PICA. METHODS: Nine patients with ruptured dissecting aneurysms of the PICA were treated with endovascular embolization at our facility from August 1997 to December 2011. A retrospective chart review study was conducted to examine the efficacy of endovascular treatment and clinical outcome. RESULTS: The shape of the aneurysms was saccular in five cases, fusiform in three cases and an abrupt cut-off of the PICA in one case. Aneurysmal sac embolization was feasible in five cases and parent artery (PICA) occlusion was performed in four cases. Eight cases (89%) achieved good recovery (modified Rankin Score ≤2). There were no clinical/technical complications in this small series. CONCLUSIONS: Endovascular treatment of ruptured dissecting aneurysms of the PICA is safe and efficient.Journal of neurointerventional surgery 10/2012; · 0.92 Impact Factor
Article: The hyperdense vessel sign on CT predicts successful recanalization with the Merci device in acute ischemic stroke.Michael T Froehler, Satoshi Tateshima, Gary Duckwiler, Reza Jahan, Nestor Gonzalez, Fernando Vinuela, David Liebeskind, Jeffrey L Saver, J Pablo Villablanca[show abstract] [hide abstract]
ABSTRACT: BACKGROUND: The success of mechanical clot retrieval for acute ischemic stroke may be influenced by the characteristics of the occlusive thrombus. The thrombus can be partly characterized by CT, as the hyperdense vessel sign (HVS) suggests erythrocyte-rich clot whereas fibrin-rich clot may be isodense. We hypothesized that the physical clot characteristics that determine CT density may also determine likelihood of retrieval with the Merci device. METHODS: We reviewed all acute stroke cases initially imaged with non-contrast CT before attempted Merci clot retrieval at a single center between 2004 and 2010. Each CT was blindly assessed for the presence or absence of the HVS, and post-retrieval angiograms were blindly assessed for reperfusion using the TICI scale. RESULTS: Of 67 patients analyzed (mean age 69; median NIHSS 19; 61% female), the HVS was seen in 42, and no HVS was present in 25. Successful recanalization was achieved in 79% of patients with the HVS (33/42), but in only 36% (9/25) of patients without HVS (p=0.001). The HVS was the only significant predictor of recanalization while accounting for age, treatment with IV-tPA, clot location, stroke etiology, time to treatment, and number of retrieval attempts. CONCLUSION: The HVS in acute ischemic stroke was strongly predictive of successful recanalization using the Merci device. The HVS may indicate thrombi that are less adhesive compared with isodense clots that are more resistant to mechanical retrieval. The absence of HVS on pre-treatment CT may thus suggest the need for a more aggressive or alternative therapeutic approach.Journal of neurointerventional surgery 05/2012; · 0.92 Impact Factor
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ABSTRACT: To discuss the validity of the hemodynamic hypothesis of aneurysm rupture, we used a patient-specific, realistic aneurysm model to reveal the flow structure and wall shear stress distribution in two cases: one with an unruptured aneurysm and the other with a ruptured aneurysm. We used particle imaging velocimetry and laser Doppler velocimetry to measure velocity profiles of intra-aneurysmal flow. Both cases had a circulating flow along the aneurysm wall, although the second case had a recirculating zone only in the minimum phase. Differences in the wall shear stress profile may identify aneurysm rupture.Experiments in Fluids 04/2012; 49(2):485-496. · 1.74 Impact Factor