Isochrone-based Identification of Gaps in Neurovascular Care in Germany.

Purpose: Modern endovascular techniques enable the treatment of various neurovascular diseases. Given the complexity of these interventions, a certification system was introduced to ensure standardized care at specialized treatment centers. We used a driving-time-based isochrone approach to identify care gaps in different German Society of Interventional Radiology (DeGIR) certified neurovascular treatment centers.

Methods: DeGIR-certified neurovascular centers for minimally invasive stroke care (module E), neurovascular vessel anomalies (module F), and neurovascular therapy (module EF) were geocoded and driving-time-based isochrones were calculated for 30, 60, 90, and 120 min. The resulting contours were aggregated and combined with the 2025 population estimates from the Global Human Settlement Layer to estimate residents' access.

Results: The analysis identified gaps in under-60-minute reachability, notably in northeastern Germany and parts of Rhineland-Palatinate, Saarland, and the southwest, with modules EF and F most affected, while module E fared better. Within 120 min, coverage was nearly complete across all modules. On a population level, 59.4% of residents lived within 30 min, 92.81% within 60 min, and 99.98% within 120 min of a module E center. Module F reached 45.8%, 84.26%, and 99.73%, respectively, with module EF showing intermediate accessibility.

Discussion: The driving-time-based isochrone approach identifies regions where access to specialized neurovascular care is limited-a critical issue in emergencies like stroke or aneurysm hemorrhage. Although immediate stroke care is generally more accessible than care for neurovascular anomalies, thrombectomy within an acceptable timeframe is not available to the entire population. These findings can guide strategies to enhance neurovascular care across Germany.