Blood Flow Into Basilar Tip Aneurysms

Abstract

We retrospectively investigated the clinical and radiological data from 111 consecutive patients who underwent endovascular treatment Background and Purpose-Hemodynamic forces may play a role in the recanalization of coiled aneurysms. The purpose of this study was to investigate the influence of presurgical hemodynamics on the efficacy of coil embolization for basilar tip aneurysms. Methods-We identified 82 patients who underwent endovascular coil embolization for basilar tip aneurysms with a followup of >1 year. Presurgical hemodynamics were investigated using computational fluid dynamics with 3-dimensional data derived from rotational angiography. During postprocessing, we quantified the rate of net flow entering the aneurysm through its neck and calculated the proportion of the aneurysmal inflow rate to the basilar artery flow rate. In addition, we investigated the correlation between the basilar bifurcation configuration and the hemodynamics. Results-Twenty-five of the 82 patients were excluded because of difficult vascular geometry reconstruction. Among the 57 examined patients, angiographic recanalization was observed in 19 patients (33.3%). The proportion of the aneurysmal inflow rate to the basilar artery flow rate and a coil packing density <30% were independent and significant predictors for the recanalization of coiled aneurysms. Additional investigation revealed that a small branch angle formed by the basilar artery and the posterior cerebral artery increased blood flow into the aneurysm. Conclusions-The proportion of the aneurysmal inflow rate to the basilar artery flow rate, influenced by the basilar bifurcation configuration, was an independent and significant predictor for recanalization after coil embolization in basilar tip aneurysms.

A new combined parameter predicts re-treatment for coil-embolized aneurysms: a computational fluid dynamics multivariable analysis study

“…The hemodynamics in recanalized aneurysms have been studied using CFD, revealing some relationships between blood flow and recanalization. 15 16 The results from the Mann–Whitney U-test or Student’s t-test in the present study also indicated hemodynamic differences between re-treatment and non-retreatment groups (see table 1 ): post-embolization Ane.V* and the Ane.V* reduction rate were also significantly different. On the other hand, although a previous report showed that the inflow rate at the aneurysmal neck was significantly higher in recanalized aneurysms before embolization, 15 our study showed no significant difference in the same parameter (NeckMF) at all stages (pre- and post-embolization, and change in rate).…”

“… 12–14 Sugiyama et al used patient-specific geometries of the pre-treated cerebral artery to analyze the blood flow and retrospectively investigated the relationships between hemodynamics and recanalization. 15 Another report focused on the post-treatment hemodynamics of an aneurysm that underwent recanalization. 16 While these results suggest that the difference between recanalization and non-recanalization is related to hemodynamic factors, these previous studies did not differentiate between the types of endovascular treatment.…”

Differences in Cerebral Aneurysm Rupture Rate According to Arterial Anatomies Depend on the Hemodynamic Environment

“…In most hemodynamic cohort studies using CFD analyses, the inlet boundary conditions are based on a typical flow velocity or flow rate of healthy subjects. 7,18 Alternatively, in other studies, the inlet boundary conditions were set so that the mean WSS at the ICA was equal to 1.5 Pa. 23 However, we found that the mean flow rate and the WSS at the ICA of the large MCA cases (Ն5 mm) were significantly higher than those of the small MCA cases (Ͻ5 mm; On-line Table 6). Thus, the mean WSS at the ICA is not constant but strongly depends on characteristics of the individual case.…”

The hemodynamic complexities underlying transient ischemic attacks in early-stage Moyamoya disease: an exploratory CFD study

“…Images had been obtained during a 6-second injection of contrast agent and a 200° rotation, with imaging at 30 frames per second for 5 seconds. The 150 projection images were reconstructed into a 3D data set of 512 × 512 × 512 isotropic voxels covering a field of view of 200 mm in all 3 directions 13,17 . DICOM files of the 3D angiography were then imported into Materialise Mimics software (Materialise, NV, Belgium) for visualization, stereolithography (STL) model creation and initial fine-tuning.…”

“…Several vascular diseases had their hemodynamic features studied using computational fluid dynamics (CFD) to understand the relationship between the pathobiology of endothelial cells and the vessel wall and blood hemodynamics and physics 12 . There is a wealth of publications for example on cerebral aneurysms, carotid stenosis and intracranial stenosis [12][13][14][15][16][17] . However, a Scopus search using the terms; "Moyamoya" + "computational fluid dynamics" or "CFD" reveals less than 10 publications that explored the blood dynamics features associated with MMD but with no possible link to early MMD pathology or symptomatology.…”