Clinical Trials

Large Vessel Occlusion

The Environment

A major challenge in stroke care is being able to quickly determine whether the stroke is being caused from a blocked, or occluded blood vessel, or by a bleed in the blood vessel. First responders currently lack prehospital diagnostic imaging tools and therefore must manually conduct stroke assessments using a variety of different scales. Different prehospital assessment scales are used in different regions and given that the results are user-dependent, they can be highly variable. Based on the outcome of the assessment, the patient will be transported to the appropriate center for care.

Patients typically receive care either at comprehensive stroke centers (CSC), which are equipped to treat both types of strokes, or at primary stroke centers, which are usually unable to treat large vessel occlusions (LVO). The decision of where to take the patient for treatment has significant ramifications: if a patient is taken to a primary stroke center and is diagnosed with an LVO, they often must be transported to a CSC, resulting in delayed treatment and progressively worse outcomes.

Study Objective

Transcranial Doppler (TCD) ultrasound is a reliable diagnostic tool for assessing the presence and severity of an LVO; however, a limiting factor of TCD is the operator’s ability to interpret the waveforms that measure cerebral blood flow velocity. This study aimed to assess the reliability of a new diagnostic biomarker for detecting LVO that is objective, intuitive, and provides physicians and first responders alike a common language for LVO assessment. The new biomarker, the Velocity Curvature Index (VCI), was compared to computed tomography angiogram (CTA), the standard of care diagnosing an LVO.

Clinical Collaborator

Erlanger Hospital, Lyerly Baptist Neurosurgery

Study Name:

EXPEDITE (Cerebral Blood Flow Velocity Morphology – Large Vessel Occlusion)

Design:

Prospective, multi-center, multi-arm, multi-cohort

Number of Subjects:

147

Status

Complete

Results

When compared to CTA, VCI demonstrated 88% accuracy. When combined with another common biomarker, Velocity Asymmetry Index (VAI), accuracy increased to 91%. These results indicate that both VCI alone, and when combined with VAI, could be used as effective tools for diagnosing an LVO.

More information can be found here.

This work was supported by the National Institute of Neurological Disorders and Stroke of the National Institutes of Health under award number 1U44NS109952.

Traumatic Brain Injury

The Environment

The brain consumes 20 percent of the body’s oxygen supply yet only accounts for 2 percent of its weight, illustrating the critical importance of uninterrupted blood flow to the brain. Traumatic brain injuries (TBI), which can range from severe head trauma to more mild injuries such as concussion, can disrupt blood flow in the brain, affecting oxygen and nutrient delivery to brain cells.

One of the most common mild traumatic brain injuries is concussion, which is a brain contusion caused by the brain quickly moving back and forth due to a sudden force against the head. Concussions are typically diagnosed via subjective manual scales but can also be assessed in hospital using magnetic resonance imaging (MRI). There is currently a lack of portable and objective tools that can diagnose concussion and subsequently determine when the brain is no longer concussed.

Study Objective

The purpose of this study was to evaluate a new method for quantifying cerebral dysfunction following mild traumatic brain injury (mild TBI). The study assessed the cerebrovascular reactivity of individuals who had sustained a clinically verified mild TBI using a newly developed transcranial Doppler ultrasonography analysis platform called quantitative cerebral hemodynamics. In addition, longitudinal data from subjects was collected multiple times after injury through recovery to develop a return-to-play determination algorithm.

Clinical Collaborator

University of California Los Angeles, Department of Pediatric Neurology

Study Name:

Advanced Morphological Analysis of Cerebral Blood Flow for Acute Concussion Diagnosis and Return-To-Play Determination

Design:

Prospective, longitudinal, single-center, multi-arm, multi-cohort

Number of Subjects:

219

Status

Complete

This work was supported by the National Institute of Neurological Disorders and Stroke of the National Institutes of Health under award number 5R44NS09220.

Intracranial Bleed

The Environment


Intracranial hemorrhaging, or bleeding in the brain, is a serious and often life-threatening injury that takes place between the brain tissue and skull or within the brain tissue itself. Intracranial bleeds can be the result of a severe head trauma or hemorrhagic stroke and must be identified and treated quickly. Intracranial bleeds are classified by the location of the bleed, as seen in the following graphic. Bleeds are especially difficult to diagnose in a pre-hospital setting, highlighting the need for a portable, easy to use screening tool to assess injury severity.

Intracranial bleeds are prevalent in the civilian sector, but also in the military, where one of the leading causes of death is intracranial bleeding due to head trauma. Because current methods for identifying the extent of brain injury are subjective and operator-dependent, they can be insufficient for identifying the need to evacuate injured personnel, monitor for worsening condition, and assess treatment effectiveness. For the military, a portable, low-cost, non-invasive assessment tool is needed to provide objective assessment so that appropriate treatments and/or evacuation plans can be made for injured personnel.

Study Objective

This study will compare the diagnostic prediction capability of robotic transcranial Doppler ultrasound (utilizing NovaSignal’s proprietary quantitative cerebral hemodynamics machine learning platform) to computed tomography (CT) imaging of subjects with traumatic brain injury. Objective assessments will be made by developing algorithms for intracranial bleed detection, prognosis, and monitoring.

Clinical Collaborator

Brooke Army Medical Center San Antonio, University of Texas Health Science Center San Antonio

Study Name:

Precision Intracranial Bleed Triage and Monitoring.

Design:

Prospective, multi-arm, multi-center,
non-invasive

Number of Subjects:

Up to 600

Status

Start in March 2020
Estimated end in March 2023

This work was supported by the Office of the Assistant Secretary of Defense for Health Affairs, through the Joint Program Committee 6/Combat Casualty Care Research Program under Award No. W81XWH-19-2-0005.  Opinions, interpretations, conclusions, and recommendations are those of the author and are not necessarily endorsed by the Department of Defense.

Intracranial Pressure

The Environment

Intracranial pressure (ICP) is the pressure exerted on the skull and brain by fluids that circulate within the skull, such as cerebrospinal fluid. Elevated ICP can cause severe complications, making ICP monitoring a critical component of managing brain injury patients who are at increased risk. However, current methods for monitoring ICP are all invasive, requiring a hole to be drilled in the skull to advance a pressure probe, or through the brain tissue into the ventricular space. Due to the invasive nature of ICP monitoring, there is a critical need to develop non-invasive, objective metrics that can guide clinical teams in the management of patients at increased risk of elevated ICP.

Study Objective

The purpose of this study is to collect data to develop an algorithmic framework which uses cerebral blood flow velocity measurements to determine correlation to, and estimate intracranial pressure measured with traditional, invasive monitoring.

For the US military’s prolonged field care program, this study will provide the ability for direct non-invasive assessment and monitoring of ICP after a closed head injury.

Clinical Collaborator

Brooke Army Medical Center San Antonio, Westchester Medical Center, New York Medical College

Study Name:

Cerebral Blood Flow Velocity Morphology for Quantification of Intracranial Pressure

Design:

Prospective, multi-center, multi cohort, non-invasive

Number of Subjects:

Up to 540

Status

Start in August 2019
Estimated end in September 2022

This work is supported by the Office of the Assistant Secretary of Defense for health Affairs, through the Joint Program Committee 6/Combat Casualty Care Research Program under Award No. W81XWH-17-2-0058. Opinions, interpretations, conclusions, and recommendations are those of NovaSignal Corp. and are not necessarily endorsed by the Department of Defense.

Patent Foramen Ovale

The Environment

A right-to-left shunt (RLS) is a condition whereby deoxygenated blood bypasses the lungs and enters circulation, leading to lower circulating oxygen in the blood. The leading cause of RLS is a patent foramen ovale (PFO), which is a hole between the left and right atria of the heart. Another complication of a PFO is that emboli may move from the right to left atria without first being filtered through the pulmonary circulatory system, leading to stroke. Every year in the US approximately 18,000 patients 18-60 present with a PFO and an embolic stroke of unknown source.

To detect a PFO, an agitated saline and air solution is injected into the bloodstream. Ultrasound is then used to detect the presence of the resulting micro air bubbles in the cerebral blood vessels. The type of ultrasound most commonly used for PFO detection is transthoracic echocardiogram (TTE).

Study Objective

This study is being performed to evaluate the shunt detection rate of the NovaGuide Intelligent Ultrasound relative to standard of care diagnostic techniques (transthoracic echocardiogram, transesophageal echocardiogram, standard of care transcranial Doppler ultrasound), and to assess the safety, accuracy, and usability of the device.

Clinical Collaborator

Clinical Collaborators Barrow Neurological Institute, Providence St. Vincent Medical Center, CHI Memorial Hospital, The University of Tennessee Health Science Center, Houston Methodist Neurological Institute, Swedish Hospital

More information can be found here.

Study Name:

NovaGuide Intelligent Ultrasound Compared to Transthoracic Echocardiography for Detection of Right-to-Left Shunt

Design:

Prospective, single-arm multi-center, non-significant risk

Number of Subjects:

Up to 150

Status

Start in October 2020
Estimated end in October 2021