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

Abstract

Purpose Flow Diverters (FD) have immensely extended the treatment of cerebral aneurysms in the past years. Complete aneurysm occlusion is a process that often takes a certain amount of time and is usually difficult to predict. Our aim was to investigate different syngo iFlow parameters in order to predict aneurysm occlusion. Methods Between 2014 and 2018 patients with unruptured cerebral aneurysms treated with a FD were reviewed. Aneurysm occlusion and complication rates have been assessed. In addition, various quantitative criteria were assessed using syngo iFlow before, after the intervention, and after short and long-term digital subtraction angiography (DSA). Results A total of 66 patients hosting 66 cerebral aneurysms were included in this study. 87.9% (n = 58) aneurysms in the anterior and 12.1% (n = 8) in the posterior circulation were treated. Adequate aneurysm occlusion at long-term follow-up (19.05 ± 15.1 months) was achieved in 90.9% (n = 60). Adequately occluded aneurysm revealed a significantly greater peak intensity delay (PI-D, p = 0.008) and intensity decrease ratio (ID-R, p < 0.001) compared to insufficiently occluded aneurysms. Increased intra-aneurysmal contrast agent intensity (>100%) after FD implantation resulted in an ID-R < 1, which was associated with aneurysm growth during follow-up DSA. Retreatment with another FD due to foreshortening and/or aneurysm growth was performed in 10.6% (n = 7). Overall morbidity and mortality rates were 1.5% (n = 1) and 0%. Conclusion The applied syngo iFlow parameters were found to be useful in predicting adequate aneurysm occlusion and foresee aneurysm growth, which might indicate the implantation of another FD.

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

“…The literature shows that iFlow parameters can be applied in a variety of ways and clinical experience is still rare, especially when it comes to flow assessment after treatment with WEB devices. Compared with the data from Gölitz et al., we believe that the parameters used in this study are easier to apply, not only because they have already shown promising and successful in vivo 13 and clinical 14 results.…”

“…The reduction of intra-aneurysmal flow remains a central hypothesis for success after treatment with a WEB device and, to the best of our knowledge, has only been investigated once in literature using in vivo color-coded imaging (syngo iFlow). 14 …”

“… 13 A recently published small clinical study using the same iFlow parameters for aneurysms after flow diverter treatment confirmed our results and showed that flow changes after flow diverter treatment significantly affect the inflow into the aneurysm. 14 Gölitz et al. also describe a significant flow-disrupting effect of the WEB device that reduces the outflow more than the inflow in their TDC analysis.…”

“… 13 To date, only 1 study is available that quantifies the hemodynamic effect of the WEB device using color-coded TDCs. 14 …”