Dataset Information

A DSA-based method using contrast-motion estimation for the assessment of the intra-aneurysmal flow changes induced by flow-diverter stents.

ABSTRACT:

Background and purpose

Flow-diverter stents modify intra-aneurysmal blood flow and induce the progressive thrombosis of intracranial aneurysms followed by stable vascular reconstruction. The aim of this study was to report a new method for the appraisal of intracranial blood flow from DSA performed during endovascular treatment procedures.

Materials and methods

A cohort of 24 patients with unruptured IAs who underwent FDS implantation was prospectively recruited. Pre- and post-DSA sequences in combination with 3D rotational angiography were acquired. The quantification of arterial and intra-aneurysmal flow was accomplished by using an optical flow approach. Flow reduction was assessed by using a new metric termed the mean aneurysm flow amplitude ratio. The correlation between the MAFA ratio and the incidence of aneurysm thrombosis was assessed by using receiver operating characteristic analysis and the Fisher exact test when the optimum Youden index was found.

Results

The quantification of flow was successfully achieved in 21 of 24 patients (87.5%). On the imaging follow-up, 18 aneurysms developed complete thrombosis (87.5%) and 3 displayed residual circulation (12.5%). The threshold analysis of the MAFA ratio significantly predicted thrombosis at 12 months below a threshold of 1.03 (P=.035). There was no significant correlation between the time for complete occlusion of the aneurysm and contrast stagnation inside the aneurysm after treatment (P>.05).

Conclusions

The MAFA ratio based on DSA flow quantification appears to be a reliable predictor for the assessment of stent treatment outcomes in this small study. These results open the door for perioperative flow quantification and provide indices that may help clinicians make appropriate intraprocedural decisions.

SUBMITTER: Pereira VM

PROVIDER: S-EPMC7964491 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:BackgroundThe implantation of flow-diverter stents for the treatment of ruptured intracranial aneurysms required further investigation.PurposeOur aim was to analyze the outcomes after flow diversion of ruptured intracranial aneurysms.Data sourcesA systematic search of 3 databases was performed for studies published from 2006 to 2018.Study selectionAccording to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we included studies (from 2010 to 2018) reporting acutely ruptured intracranial aneurysms treated with flow diversion.Data analysisRandom-effects meta-analysis was used to pool the following: aneurysm occlusion rate, complications, rebleeding, and factors influencing the studied outcomes.Data synthesisWe included 20 studies evaluating 223 patients with acutely ruptured intracranial aneurysms treated with flow-diverter stents. Immediate angiographic occlusion was obtained in 32% (29/86; 95% CI, 15.4%-48%; I2 = 79.6%) of aneurysms, whereas long-term complete/near-complete aneurysm occlusion was 88.9% (162/189; 95% CI, 84%-93.5%; I2 = 20.9%) (mean radiologic follow-up of 9.6 months). The treatment-related complication rate was 17.8% (42/223; 95% CI, 11%-24%; I2 = 52.6%). Complications were higher in the posterior circulation (16/72 = 27%; 95% CI, 14%-40%; I2 = 66% versus 18/149 = 11.7%; 95% CI, 7%-16%; I2 = 0%) (P = .004) and after treatment with multiple stents (14/52 = 26%; 95% CI, 14%-45%; I2 = 59%) compared with a single stent (20/141 = 10%; 95% CI, 5%-15%; I2 = 0%) (P = .004). Aneurysm rebleeding after treatment was 4% (5/223; 95% CI, 1.8%-7%; I2 = 0%) and was higher in the first 72 hours.LimitationsSmall and retrospective series.ConclusionsFlow-diversion treatment of ruptured intracranial aneurysms yields a high rate of long-term angiographic occlusion with a relatively low rate of aneurysm rebleeding. However, treatment is associated with a complication rate of 18%. When coiling or microsurgical clipping are not feasible strategies, anterior circulation ruptured aneurysms can be effectively treated with a flow-diversion technique, minimizing the number of stents deployed. Given the 27% rate of complications, flow diversion for ruptured posterior circulation aneurysms should be considered only in selected cases not amenable to other treatments.

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