2D parametric contrast time-density analysis for the prediction of complete aneurysm occlusion at six months’ post-flow diversion stent

Abstract

<jats:sec><jats:title>Objective</jats:title><jats:p> Indications for the treatment of cerebral aneurysms with flow diversion stents are expanding. The current aneurysm occlusion rate at six months ranges between 60 and 80%. Predictability of complete vs. partial aneurysm occlusion is poorly defined. Here, we evaluate the angiographic contrast time-density as a predictor of aneurysm occlusion rate at six months’ post-flow diversion stents. </jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p> Patients with unruptured cerebral aneurysms proximal to the internal carotid artery terminus treated with single flow diversion stents were included. 2D parametric parenchymal blood flow software (Siemens-Healthineers, Forchheim, Germany) was used to calculate contrast time-density within the aneurysm and in the proximal adjacent internal carotid artery. The area under the curve ratio between the two regions of interests was assessed at baseline and after flow diversion stents deployment. The area under the curve ratio between completely vs. partially occluded aneurysms at six months’ follow-up was compared. </jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p> Thirty patients with 31 aneurysms were included. Mean aneurysm diameter was 8 mm (range 2–28 mm). Complete occlusion was obtained in 19 aneurysms. Younger patients ( P = 0.006) and smaller aneurysms ( P = 0.046) presented higher chance of complete obliteration. Incomplete occlusion of the aneurysm was more likely if the area under the curve contrast time-density ratio showed absolute ( P = 0.001) and relative percentage ( P = 0.001) decrease after flow diversion stents deployment. Area under ROC curve was 0.85. </jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p> Negative change in the area under the curve ratio indicates less contrast stagnation in the aneurysm and lower chance of occlusion. These data provide a real-time analysis after aneurysm treatment. If validated in larger datasets, this can prompt input to the surgeon to place a second flow diversion stents. </jats:p></jats:sec>

Retrospective analysis of intracranial aneurysms after flow diverter treatment including color-coded imaging (syngo iFlow) as a predictor of aneurysm occlusion

“…Hussein et al also observed increased intra-aneurysmal flow changes after FD treatment in their small cases study. 20 The iFlow TDCs reported in their publication were comparable to those from our study. In contrast to our study, the observed flow changes were not associated with an aneurysm growth, but with the possibility of complete occlusion of the treated aneurysms.…”

“…The literature shows that hemodynamic analysis of treated cerebral aneurysms using iFlow remains a heterogeneous and highly user-dependent method. 19,20,39,40 The parameters assessed in this study are just one of the many ways to analyze such data, so that a direct comparison of our results with similar studies seems to be difficult. In addition, DSA acquisition was performed by manual injection of a contrast agent rather than mechanically using an injector as this is our clinical standard.…”

“…18 Unfortunately, there are only few studies today that have used color-coded imaging to evaluate the prediction of aneurysm occlusion following flow diverter treatment. 19,20 The purpose of this retrospective study was to apply the previously described syngo iFlow parameters 18 in a clinical setting and to evaluate their predictive value for aneurysm occlusion after flow diverter treatment.…”

“…18 Unfortunately, there are only few studies today that have used color-coded imaging to evaluate the prediction of aneurysm occlusion following flow diverter treatment. 19,20…”

Treatment of Wide-Necked Cerebral Aneurysms Using the WEB Device Including Flow Alteration Assessment With Color-Coded Imaging: A Single Center Experience

“…Hemodynamic analysis of cerebral aneurysms using iFlow remains a heterogeneous method. 13 , 15 , 25 The parameters assessed in this study are just one of the many ways to analyze such data, which makes a direct comparison of our results with similar studies difficult. Additionally, the DSA acquisition was performed by manual injection of a contrast agent instead of mechanical injection, as this is our clinical standard.…”