Abstract
Effects of stroke therapies area highly time dependent but onset-to-treatment times for recanalizing treatment are mostly beyond optimal time windows. Mobile stroke units shorten time to treatment and improve functional outcome. However, costs and logistical demands preclude their widespread use. There is a pressing need for alternative prehospital diagnostic tools that enable early, on-site treatment and facilitate targeted transport in patients needing interventional therapies. This systematic review aimed at examining the current landscape of noncomputed tomography-based technologies for prehospital stroke diagnosis. We conducted a literature search of original research papers on predetermined technologies and through systematic scouting on PubMed and included papers in English found through MEDLINE and Embase, published until October 2025. Relevant papers not identified by the systematic search but known to the authors were included and indicated as such. The final review included 105 publications evaluating innovations in microwave, transcranial eddy current damping, volumetric impedance phase shift spectroscopy, ultrasound, magnetic resonance imaging, electroencephalography, near-infrared spectroscopy, blood biomarkers, telemedicine, and artificial intelligence. Each technology's potentials, limitations, and clinical feasibility for enhancing prehospital diagnosis and therapeutic and monitoring utility were assessed. No single technology provides capabilities similar to noncomputed tomography in terms of detection and differentiation of ischemic and hemorrhagic stroke. A combination of ultrasound and near-infrared spectroscopy may complement each other in hemorrhage detection. Electroencephalography shows most promise in identifying large vessel occlusion. Telemedicine can be used for reliable prehospital stroke assessment. Future research should target both the improvement of individual technologies as well as combining different modalities.