Clinical Significance of Conversion From Computational Fluid Dynamics to Morphology for Risk Evaluation of Aneurysm Recurrence After Coiling

Neurosurgery ◽  
2019 ◽  
Vol 66 (Supplement_1) ◽  
Author(s):  
Kouichi Misaki ◽  
Iku Nambu ◽  
Takehiro Uno ◽  
Akifumi Yoshikawa ◽  
Naoyuki Uchiyama ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Pressure Difference ◽  
Risk Evaluation ◽  
Internal Carotid ◽  
Critical Role ◽  
Parent Artery ◽  
Characteristic Analysis

Abstract INTRODUCTION Hemodynamic factors play a critical role in the recurrence of intracranial aneurysms after coiling. However, the computational fluid dynamics (CFD) analyses are not consistently performed all over the world, and its benefits were limited in the specific institutes. We tried to convert the hemodynamic parameters to morphological factors for the risk evaluation of aneurysm recurrence after coiling. METHODS Using pretreatment 3-dimensional rotational angiography data of 50 internal carotid artery aneurysms (7 recanalized, 43 stable) treated with endovascular coiling, we created a virtual post-coiling model produced by cutting the aneurysm dome for construction of virtual coil plane. At the virtual coil plane, we evaluated the pressure difference, which was defined as the pressure elevation at the coil plane from the parent artery divided by the dynamic pressure at the parent artery. After a statistical analysis of the relationship between the pressure difference and aneurysm recurrence, we performed statistical comparisons of pressure difference with morphological factors. RESULTS Recanalized aneurysms showed a significantly higher pressure difference than stable aneurysms (P < .001). The receiver operating characteristic analysis showed that the area under the curve value for the pressure difference (0.967). Morphologically, all 5 aneurysms that had the virtual coil plane at the line of upper border of internal carotid artery had a significantly higher pressure difference (P < .001) and recurred after coiling (P < .001). CONCLUSION The pressure difference in the virtual post-coiling model had a strong association with aneurysm recurrence after coiling. Additionally, the location of the coil plane as a morphological factor was significantly associated with pressure difference and aneurysm recurrence. The conversion of hemodynamic factors into simple morphological factors may contribute to expanded applications of the CFD analysis.

Computational Fluid Dynamics of Carotid Arteries After Carotid Endarterectomy or Carotid Artery Stenting Based on Postoperative Patient-Specific Computed Tomography Angiography and Ultrasound Flow Data

Neurosurgery ◽  
2011 ◽  
Vol 68 (4) ◽  
pp. 1096-1101 ◽  
Author(s):  
Hitoshi Hayase ◽  
Koji Tokunaga ◽  
Toshio Nakayama ◽  
Kenji Sugiu ◽  
Ayumi Nishida ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computed Tomography ◽  
Computational Fluid Dynamics ◽  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Carotid Arteries ◽  
Internal Carotid ◽  
Patient Specific ◽  
Flow Data ◽  
Simulation Results

Abstract BACKGROUND: There are significant differences in the postoperative morphological and hemodynamic conditions of the carotid arteries between carotid artery stenting (CAS) and endarterectomy (CEA). OBJECTIVE: To compare the postoperative rheological conditions after CAS with those after CEA with patch angioplasty (patch CEA) through the use of computational fluid dynamics (CFD) based on patient-specific data. METHODS: The rheological conditions in the carotid arteries were simulated in 2 patients after CAS and in 2 patients after patch CEA by CFD calculations. Three-dimensional reconstruction of the carotid arteries was performed with the images obtained with computed tomography angiography. The streamlines and wall shear stress (WSS) were calculated by a supercomputer. Adequate boundary conditions were determined by comparing the simulation results with ultrasound flow data. RESULTS: CFD was successfully calculated for all patients. The differences between the flow velocities of ultrasound data and those of the simulation results were limited. In the streamline analysis, the maximum flow velocities in the internal carotid artery after patch CEA were around two-thirds of those after CAS. Rotational slow flow was observed in the internal carotid artery bulb after patch CEA. WSS analysis found regional low WSS near the outer wall of the bulb. High WSS was observed at the distal end of the arteriotomy after patch CEA and at the residual stenosis after CAS. CONCLUSION: CFD of postoperative carotid arteries disclosed the differences in streamlines and WSS between CAS and patch CEA. CFD may allow us to obtain adequate rheological conditions conducive to achieving the best clinical results.

How patient-specific do internal carotid artery inflow rates need to be for computational fluid dynamics of cerebral aneurysms?

2020 ◽  
pp. neurintsurg-2020-015993 ◽  
Author(s):  
Mehdi Najafi ◽  
Nicole M Cancelliere ◽  
Olivier Brina ◽  
Pierre Bouillot ◽  
Maria I Vargas ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Internal Carotid ◽  
Spectral Power ◽  
Cerebral Aneurysms ◽  
Patient Specific ◽  
Perfect Agreement ◽  
The Impact

BackgroundComputational fluid dynamics (CFD) has become a popular tool for studying ‘patient-specific’ blood flow dynamics in cerebral aneurysms; however, rarely are the inflow boundary conditions patient-specific. We aimed to test the impact of widespread reliance on generalized inflow rates.MethodsInternal carotid artery (ICA) flow rates were measured via 2D cine phase-contrast MRI for 24 patients scheduled for endovascular therapy of an ICA aneurysm. CFD models were constructed from 3D rotational angiography, and pulsatile inflow rates imposed as measured by MRI or estimated using an average older-adult ICA flow waveform shape scaled by a cycle-average flow rate (Qavg) derived from the patient’s ICA cross-sectional area via an assumed inlet velocity.ResultsThere was good overall qualitative agreement in the magnitudes and spatial distributions of time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), and spectral power index (SPI) using generalized versus patient-specific inflows. Sac-averaged quantities showed moderate to good correlations: R2=0.54 (TAWSS), 0.80 (OSI), and 0.68 (SPI). Using patient-specific Qavg to scale the generalized waveform shape resulted in near-perfect agreement for TAWSS, and reduced bias, but not scatter, for SPI. Patient-specific waveform had an impact only on OSI correlations, which improved to R2=0.93.ConclusionsAneurysm CFD demonstrates the ability to stratify cases by nominal hemodynamic ‘risk’ factors when employing an age- and vascular-territory-specific recipe for generalized inflow rates. Qavg has a greater influence than waveform shape, suggesting some improvement could be achieved by including measurement of patient-specific Qavg into aneurysm imaging protocols.

Computational Fluid Dynamics to Evaluate the Management of a Giant Internal Carotid Artery Aneurysm

2015 ◽  
Vol 83 (6) ◽  
pp. 1057-1065 ◽  
Author(s):  
Jonathan Russin ◽  
Haithem Babiker ◽  
Justin Ryan ◽  
Leonardo Rangel-Castilla ◽  
David Frakes ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Internal Carotid ◽  
Artery Aneurysm ◽  
Carotid Artery Aneurysm ◽  
Internal Carotid Artery Aneurysm

scholarly journals Prediction of internal carotid artery aneurysm recurrence by pressure difference at the coil mass surface

2020 ◽  
Author(s):  
Takehiro Uno ◽  
Kouichi Misaki ◽  
Iku Nambu ◽  
Akifumi Yoshikawa ◽  
Tomoya Kamide ◽  
...  
Keyword(s):  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Coil Embolization ◽  
Pressure Difference ◽  
Internal Carotid ◽  
Strong Predictor ◽  
Area Under The Curve ◽  
Artery Aneurysm ◽  
Characteristic Analysis ◽  
Internal Carotid Artery Aneurysm

Abstract Purpose A previous study on computational fluid dynamics reported that a high pressure difference (PD) at the surface of a coil mass is a strong predictor of aneurysm recurrence after coil embolization. PD was calculated using a virtual post-coiling model (VM), created by manually cutting the aneurysm by the flat plane from an anatomic model created with pre-coil embolization data; however, its credibility has not been fully evaluated. This study aims to clarify whether PD values calculated using the post-coiling model, which reflects the actual coil plane, are a strong predictor of aneurysm recurrence. Methods Fifty internal carotid artery aneurysms treated with endovascular coil embolization were analyzed (7 recanalized, 43 stable). We created and subjected two post-coiling models, namely, VM and the real post-coiling model (RM), constructed from the post-coil embolization data. The relationship between PD and aneurysm recurrence was examined using these models. PD and its constituent three parameters were compared between VM and RM. Results PD values calculated using RM showed significantly higher aneurysm recurrence in recurrence group than stable group (p < 0.001), and multivariate analysis showed that PD in RM (p = 0.02; odds ratio, 36.24) was significantly associated with aneurysm recurrence. The receiver operating characteristic analysis revealed that PD values accurately predicted aneurysm recurrence (area under the curve, 0.977; cutoff value, 3.08; sensitivity, 100%; specificity, 97.7%). All four parameters showed a significant correlation with VM and RM (p < 0.001). Conclusion Use of PD to predict recurrence after coil embolization can be clinically relevant.

scholarly journals Optimization of duplex velocity criteria for diagnosis of internal carotid artery (ICA) stenosis: A report of the Intersocietal Accreditation Commission (IAC) Vascular Testing Division Carotid Diagnostic Criteria Committee

2021 ◽  
pp. 1358863X2110112
Author(s):  
Heather L Gornik ◽  
Tatjana Rundek ◽  
Hannah Gardener ◽  
James F Benenati ◽  
Nirvikar Dahiya ◽  
...  
Keyword(s):  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Diagnostic Criteria ◽  
Internal Carotid ◽  
Peak Systolic Velocity ◽  
Duplex Ultrasound ◽  
Additional Parameter ◽  
Characteristic Analysis ◽  
Carotid Duplex ◽  
Ica Stenosis

Diagnostic criteria to classify severity of internal carotid artery (ICA) stenosis vary across vascular laboratories. Consensus-based criteria, proposed by the Society of Radiologists in Ultrasound in 2003 (SRUCC), have been broadly implemented but have not been adequately validated. We conducted a multicentered, retrospective correlative imaging study of duplex ultrasound versus catheter angiography for evaluation of severity of ICA stenosis. Velocity data were abstracted from bilateral duplex studies performed between 1/1/2009 and 12/31/2015 and studies were interpreted using SRUCC. Percentage ICA stenosis was determined using North American Symptomatic Carotid Endarterectomy Trial (NASCET) methodology. Receiver operating characteristic analysis evaluated the performance of SRUCC parameters compared with angiography. Of 448 ICA sides (from 224 patients), 299 ICA sides (from 167 patients) were included. Agreement between duplex ultrasound and angiography was moderate (κ = 0.42), with overestimation of degree of stenosis for both moderate (50–69%) and severe (⩾ 70%) ICA lesions. The primary SRUCC parameter for ⩾ 50% ICA stenosis of peak-systolic velocity (PSV) of ⩾ 125 cm/sec did not meet prespecified thresholds for adequate sensitivity, specificity, and accuracy (sensitivity 97.8%, specificity 64.2%, accuracy 74.5%). Test performance was improved by raising the PSV threshold to ⩾ 180 cm/sec (sensitivity 93.3%, specificity 81.6%, accuracy 85.2%) or by adding the additional parameter of ICA/common carotid artery (CCA) PSV ratio ⩾ 2.0 (sensitivity 94.3%, specificity 84.3%, accuracy 87.4%). For ⩾ 70% ICA stenosis, analysis was limited by a low number of cases with angiographically severe disease. Interpretation of carotid duplex examinations using SRUCC resulted in significant overestimation of severity of ICA stenosis when compared with angiography; raising the PSV threshold for ⩾ 50% ICA stenosis to ⩾ 180 cm/sec as a single parameter or requiring the ICA/CCA PSV ratio ⩾ 2.0 in addition to PSV of ⩾ 125 cm/sec for laboratories using the SRUCC is recommended to improve the accuracy of carotid duplex examinations.

scholarly journals Enlarged Parent Artery Lumen at Aneurysmal-Neck Segment in Wide-Necked Distal Internal Carotid Artery Aneurysms

2015 ◽  
Vol 10 (2) ◽  
pp. 82 ◽  
Author(s):  
Jong Won Lee ◽  
Jung Min Woo ◽  
Ok Kyun Lim ◽  
Ye-eun Jo ◽  
Jae Kyun Kim ◽  
...  
Keyword(s):  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Internal Carotid ◽  
Parent Artery ◽  
Distal Internal Carotid Artery ◽  
Aneurysmal Neck

Blister Aneurysms of the Internal Carotid Artery: Microsurgical Results and Management Strategy

Neurosurgery ◽  
2017 ◽  
Vol 80 (2) ◽  
pp. 235-247 ◽  
Author(s):  
Christopher M. Owen ◽  
Nicola Montemurro ◽  
Michael T. Lawton
Keyword(s):  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Treatment Strategy ◽  
Internal Carotid ◽  
Artery Bypass ◽  
External Carotid ◽  
Parent Artery ◽  
Intraoperative Rupture

Abstract BACKGROUND: Blister aneurysms of the supraclinoid internal carotid artery (ICA) are challenging lesions with high intraoperative rupture rates and significant morbidity. An optimal treatment strategy for these aneurysms has not been established. OBJECTIVE: To analyze treatment strategy, operative techniques, and outcomes in a consecutive 17-year series of ICA blister aneurysms treated microsurgically. METHODS: Seventeen patients underwent blister aneurysm treatment with direct clipping, bypass and trapping, or clip-reinforced wrapping. RESULTS: Twelve aneurysms (71%) were treated with direct surgical clipping. Three patients required bypass: 1 superficial temporal artery to middle cerebral artery bypass, 1 external carotid artery to middle cerebral artery bypass, and 1 ICA to middle cerebral artery bypass. One patient was treated with clip-reinforced wrapping. Initial treatment strategy was enacted 71% of the time. Intraoperative rupture occurred in 7 patients (41%), doubling the rate of a poor outcome (57% vs 30% for patients with and without intraoperative rupture, respectively). Severe vasospasm developed in 9 of 16 patients (56%). Twelve patients (65%) were improved or unchanged after treatment, and 10 patients (59%) had good outcomes (modified Rankin Scale scores of 1 or 2). CONCLUSION: ICA blister aneurysms can be cautiously explored and treated with direct clipping as the first-line technique in the majority of cases. Complete trapping of the parent artery with temporary clips and placing permanent clip blades along normal arterial walls enables clipping that avoids intraoperative aneurysm rupture. Trapping/bypass is used as the second-line treatment, maintaining a low threshold for bypass with extensive or friable pathology of the carotid wall and in patients with incomplete circles of Willis.

Balloon Migration into a Giant Carotid Aneurysm after Parent Artery Occlusion Using Detachable Balloons

1998 ◽  
Vol 4 (4) ◽  
pp. 323-328 ◽  
Author(s):  
A. Uchino ◽  
P.K. Maurer ◽  
H.S. Brara ◽  
Y. Numaguchi
Keyword(s):  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Internal Carotid ◽  
Artery Occlusion ◽  
Parent Artery ◽  
Parent Artery Occlusion ◽  
Occlusion Technique ◽  
Large Aneurysm ◽  
The Right

We treated a 70-year-old man with a giant paraophthalmic region aneurysm of the right internal carotid artery using the parent artery occlusion technique with three detachable balloons. Initially, the patient did well, but migration of the distal balloon into the aneurysm was detected seven months later. This report suggests that initial parent artery occlusion using balloons will not always induce permanent thrombosis of a large aneurysm, because the occlusion and thrombosis is strictly dependant on the position of the balloons that are used, and adjunct use of coils may be indicated.

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