Study to Test Sensitivity and Specificity of Passive Wave Pressure Device in Determining Ischemic Stroke

That the Jan Medical Nautilus NeuroWaveTM system provides significantly higher sensitivity to hyper acute ischemic stroke than does CT.

In spite of the fact that approximately 800,000 strokes are diagnosed in the United States each year, many physicians and patients have approached the management of stroke with a sense of futility. However, within the past 2 decades, following the advent of computerized tomography (CT), medical interest has turned toward stroke and effective interventions to treat and prevent it have received attention.

CT and/or magnetic resonance imaging (MRI) are the typical diagnostic tools used in the event of a stroke alert. These studies are done on an emergent or urgent basis, since, to be effective, treatments for ischemic and hemorrhagic stroke must be delivered soon after onset of the illness. In an effort to institute an appropriate therapeutic regime, laboratory and structural diagnostic studies are required to be done as rapidly as possible to determine pathological etiology, size, and location of concern.

The speed at which a diagnosis is made and a treatment plan established often determines patient outcome and any associated complications. This is especially true when evaluating patients for ischemic stroke where there is a narrow 3 hour window of opportunity in which to resolve the clot with IV .before permanent neurological impairment results, and up to 8 additional hours with the use if intra arterial (IA) t-PA or interventional mechanical embolectomy procedures are utilized. Current treatment modalities include pharmacologic thrombolytic drugs utilized to disrupt or dissolve clots located in the distal vasculature or mechanical intervention in larger vessels. Since many patients do not recognize the symptoms of stroke they do not seek medical attention immediately. Significant time is then often lost from the onset of the stroke before seeking medical help / treatment.

Although the current technologies are quite adequate as diagnostic tools for hemorrhagic stroke and for identifying subdural hematomas, and other pooled blood abnormalities which would preclude t-PA therapy, they are largely ineffective at positively identifying stroke during the limited therapeutic window of time. Positive identification of ischemia itself is rarely possible or practical with CT or within the limited therapeutic window. As such the diagnostic determination and associated treatment decisions are based on the unsatisfactory basis of exclusion.

Eligibility Criteria:
Inclusion Criteria:

* Symptoms consistent with stroke with known onset \< 12 hours prior to enrollment and planned recording with the Nautilus NeuroWave System
* Suspected pathology of following vessels: internal carotid artery, ACA, MCA, PCA, basilar or other anterior or posterior cerebral vessels or normal anatomy
* Subject is planned to undergo standard stroke triage imaging protocol
* Able to understand and provide signed informed consent, or have a Legally Authorized Representative willing to provide informed consent on subject's behalf

Exclusion Criteria:

* Known to meet hospital criteria for brain death
* Not a candidate for CT, MRI
* unknown time of stroke symptom onset.
* Psychologically unstable and not able to cooperate
* Not suitable for participation in this study in the opinion of the Investigator