Prehospital and Emergency Room Stroke Diagnosis Using Quantitative Cerebral Hemodynamics

Large vessel acute ischemic strokeAISis the leading cause of disability and fourth leading cause of death with approximatelyper year in the United States aloneAlthough treatments including interventionalstentrieverand pharmaceuticaltPAexist for large vessel occlusionLVOthere is not a rapid prehospital tool for diagnoses which guides the use of the correct therapyBecause the time to treatment for stroke is criticalthere is a large need for a device which can be used in ambulances and other prehospital environments so that patients are rapidly provided the correct careCurrentlycomputed tomography angiographyCTAimaging is the standard of care but its use is limited to the hospital or in some cases multimillion dollar stroke on wheels ambulances which are not practicalThere is a significant delay that occurs between stroke onset and diagnosis by the time CTA is performed and read resulting in unnecessary death or disabilityMore delay occurs when patients need to be transferred to a stroke center because the hospital they are at does not perform interventional therapyRapid diagnosis in a prehospital setting will enable patients to be taken to the correct hospital and provide LVO location to surgeons in the operating suiteAs the critical factor affecting cerebral anatomy in AIS patients is the limitation of blood flow to the brain the most likely technology to assist in diagnosis of LVO is one that can measure flow directlyTranscranial DopplerTCDhas been used to directly measure blood flow velocity sincebut it relies on a trained operator skilled in both finding the affected vessel as well as interpreting a complicated waveformGuidelines already exist for how to diagnose LVO with TCD and hospitals with a trained operator currently use itHoweverit s not used in smaller hospitalsurgent care or ambulance settings due to the training requirementsThis work will revolutionize TCD for stroke diagnosis because it removes the need for a trained operatorkey for mass adoption of the technologyTCD is already small and portable so it can easily fit in an ambulance similar in size to an automated external defibrillatorThis work will use machine learning techniques we have developed to analyze the morphology of TCD waveforms and provide diagnosis informationThe key is the ability to remove the operator variability by understanding how waveform morphology of stroke changes based on depth relative to occlusion so that the need to measure in a precise location is eliminatedOur preliminary results showaccuracy for LVO diagnosis but we need to broaden our dataset while updating our algorithmsPhase I will use our FDA Cleared Lucid MTranscranial Doppler Ultrasound System to measure confirmed stroke subjects after CTA imaging and update our algorithmPhase II will use algorithms developed in Phase I with a fully automated TCD system we have developed with investor funding that does not require an operator or trained sonographerWe currently have Western IRB approval and are upgrading usability features of the device for ease of use with minimal training Large vessel acute ischemic strokeAISis the leading cause of disability and fourth leading cause of death with approximatelyper year in the United States aloneThis work will reduce the time to treatment for stroke by developing necessary algorithms to diagnose AIS with a portable ultrasound technology which measures cerebral blood flow velocitySuccessful completion of this project will result in a portable diagnostic device suitable for use in prehospital settings similar to automated external defibrillator for heart attack