85 research outputs found
The effect of aneurysm geometry on the intra-aneurysmal flow condition
Various anatomical parameters affect on intra-aneurysmal hemodynamics. Nevertheless, how the shapes of real patient aneurysms affect on their intra-aneurysmal hemodynamics remains unanswered.
Quantitative computational fluid dynamics simulation was conducted using eight patientsâ angiograms of internal carotid arteryâophthalmic artery aneurysms. The mean size of the intracranial aneurysms was 11.5Â mm (range 5.8 to 19.9Â mm). Intra-aneurysmal blood flow velocity and wall shear stress (WSS) were collected from three measurement planes in each aneurysm dome. The correlation coefficients (r) were obtained between hemodynamic values (flow velocity and WSS) and the following anatomical parameters: averaged dimension of aneurysm dome, the largest aneurysm dome dimension, aspect ratio, and domeâneck ratio.
Negative linear correlations were observed between the averaged dimension of aneurysm dome and intra-aneurysmal flow velocity (râ=ââ0.735) and also WSS (râ=ââ0.736). The largest dome diameter showed a negative correlation with intra-aneurysmal flow velocity (râ=ââ0.731) and WSS (râ=ââ0.496). The aspect ratio demonstrated a weak negative correlation with the intra-aneurysmal flow velocity (râ=ââ0.381) and WSS (râ=ââ0.501). A clear negative correlation was seen between the intra-aneurysmal flow velocity and the domeâneck ratio (râ=ââ0.708). A weak negative correlation is observed between the intra-aneurysmal WSS and the domeâneck ratio (râ=ââ0.392).
The aneurysm dome size showed a negative linear correlation with intra-aneurysmal flow velocity and WSS. Wide-necked aneurysm geometry was associated with faster intra-aneurysmal flow velocity
Genetic diversity of HLA system in four populations from Baja California, Mexico: Mexicali, La Paz, Tijuana and rural Baja California
We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 250 Mexicans from the states of Baja California Norte and Baja California Sur living in Mexicali (NâŻ=âŻ100), La Paz (NâŻ=âŻ75), Tijuana (NâŻ=âŻ25) and rural communities (NâŻ=âŻ50) to obtain information regarding allelic and haplotypic frequencies. The most frequent haplotypes for the Baja California region include nine Native American and five European haplotypes. Admixture estimates revealed that the main genetic components are European (50.45âŻÂ±âŻ1.84% by ML; 42.03% of European haplotypes) and Native American (43.72âŻÂ±âŻ2.36% by ML; 40.24% of Native American haplotypes), while the African genetic component was less apparent (5.83âŻÂ±âŻ0.98% by ML; 9.36% of African haplotypes)
SystĂšmes veineux de la base du crĂąne et de la jonction cranio-cervicale : anatomie macroscopique et radiologique et implications cliniques
Il s'agit d'une Ă©tude sur l'anatomie macroscopique et radiologique des systĂšmes veineux de la base du crĂąne et de la jonction cranio-cervicale. L'utilisation de mĂ©thodes d'investigation diverses sur le cadavre et le vivant, basĂ©es d'une part sur la dissection classique et des Ă©tudes de corrosions veineuses, et d'autre part sur l'artĂ©riographie digitalisĂ©e de soustraction et l'angiographie IRM et CT, permettent d'appprĂ©hender cette anatomie complexe. L'accent est portĂ© sur des trouvailles anatomiques Ă ce jour mĂ©connues et sur des imprĂ©cisions qui font foi dans la littĂ©rature. L'optique sera surtout celle du clinicien, orientant la discussion vers des donnĂ©es anatomiques dont les implications cliniques auront un intĂ©rĂȘt pour le neuroradiologue ou pour le neurochirurgien. L'illustration par des cas cliniques concrets a pour but de renforcer cette optique. Finalement, une nouvelle classification du drainage veineux de la base du crĂąne est proposĂ©e
Intra-arterial onyx embolisation of sphenobasilar sinus fistula using pressure cooker technique: case report and review of the literature
Letter to the Editor Regarding âImmediate Development of Dural Arteriovenous Fistula After Middle Meningeal Artery Embolization: First Angiographic Demonstrationâ
The Laterocavernous Sinus System: Venous Inflows, Venous Outflows, and Clinical Significance
In Reply to the Letter to the Editor Regarding âImmediate Development of Dural Arteriovenous Fistula After Middle Meningeal Artery Embolization: First Angiographic Demonstrationâ
Alternative route to a hypoglossal canal dural arteriovenous fistula in case of failed jugular vein approach
Intraoperative cone-beam computed tomography contributes to avoiding hypoglossal nerve palsy during transvenous embolization for dural arteriovenous fistula of the anterior condylar confluence
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