Exploring the relationship between case volume and intracranial aneurysm treatments with flow-diverters and flow-disruptors: Insights from the 2020 to 2021 Database of the German Society for Interventional Radiology National Registry in Germany.

Background and purpose: Intracranial aneurysm treatment using flow-diverters and flow-disruptors requires a higher level of expertise when compared to more traditional methods. Our hypothesis was that the procedural success and the rate of complications are dependent on the annual case load of a center.

Materials and methods: Conducting a retrospective analysis on the Database of the German Society for Interventional Radiology for the years 2020 to 2021, we examined flow-diverter and flow-disruptor procedures. We categorized centers into four groups according to their annual case load and proceeded to analyze success rates, complication rates, and fluoroscopy times across these centers.

Results: No statistically significant differences were observed among the groups in both flow-diverter and flow-disruptor cases concerning fluoroscopy time and the incidence of technical complications. However, within the subgroup of flow-disruptor cases, centers with lower case load exhibited significantly higher rates of hemorrhagic and clinically relevant complications. Additionally, it was noted that the rate of therapeutic success in the flow-diverter group significantly increased in centers with higher case volumes.

Conclusion: Our findings support the intention towards centralization of medical care especially for complex neuroendovascular procedures. Furthermore, our findings are an argument to further develop a standardized educational and procedural algorithm based on defined case numbers and training modules for complex neurovascular procedures as already implemented by the Database of the German Society for Interventional Radiology.