Abstract Body: Introduction: Timely diagnosis is essential in stroke management, but current imaging modalities, including CT and MRI, face limitations in availability and can lead to delays in diagnosis, adversely impacting patient outcomes. This study introduces and validates a novel, portable, noninvasive sensor for real-time stroke detection, designed for ease of use by first responders and at bedside, enhancing point-of-care assessment.

Hypothesis: Eddy current damping sensors, commonly employed in automotive and aerospace applications for flaw detection, operate through indirect, non-contact electrical conductivity measurements. We hypothesize that patients with intracranial bleeding exhibit elevated conductivity due to iron ions in blood pools, differentiating them from healthy individuals.

Objectives: This technology leverages eddy current damping sensors as an affordable, portable option to triage hemorrhagic stroke patients in settings with limited access to CT and MRI, such as rural or combat environments. Immediate detection capabilities could markedly improve stroke management and patient outcomes.

Methods: Our teams at the University of Southern California and the California Institute of Technology conducted benchtop, phantom, and clinical experiments. Benchtop and phantom tests simulated various stroke sizes, depths, and locations. Additionally, IRB-approved clinical trials are underway at USC Keck School of Medicine, involving patients admitted for cerebral hemorrhage, edema, or hematoma with a CT and/or MRI, excluding those who have undergone draining, clipping, or craniotomy.

Findings: The sensor reliably detected conductivity differences between normal brain tissue and stroke regions across benchtop, phantom, and clinical settings. In the benchtop setup, 462 data points yielded a sensitivity of 90%, while phantom setup results from 40 data points showed a sensitivity of 100%. Clinical trials with 34 patients resulted in a sensitivity of 83%, underscoring the device’s potential effectiveness in clinical scenarios.

Conclusion: This portable eddy current damping sensor demonstrates high sensitivity and specificity for real-time, noninvasive differentiation between hemorrhagic stroke patients and healthy individuals.