Topics

Cerebrovascular Reactivity Assessed With fNIRS as a Biomarker of TCVI After Acute Traumatic Brain Injury in Military

2019-08-20 20:17:08 | BioPortfolio

Summary

The study includes people who have recently had a traumatic brain injury (TBI) and healthy controls who have not had a TBI and is designed to measure brain blood flow serially after a TBI. Studies have shown that small blood vessels in the brain may be injured during a TBI. The goal is to learn about brain blood vessel function from as early as the first week to 6 months after a TBI . The study uses Near Infrared Spectroscopy (NIRS) which uses small lights that detect oxygen levels in the blood, measuring blood flow in the brain. This is compared with magnetic resonance imaging (MRI). When blood flow increases in the brain in response to a stimulus, this is called cerebral vascular reactivity (CVR).

The study aims to learn about CVR using a few minutes of special breathing similar to breath holding while in an MRI (magnetic resonance imaging), and CVR measures after one dose of a common drug called sildenafil (generic Viagra) 50 mg taken once during CVR measurements at each of up to 4 visits. The investigators will measure CVR at different times during a 6-month period in participants who have had a TBI to see how CVR measures and blood vessels function during the first 6 months after a brain injury.

Description

Background and significance:

Currently, more that 5.3 million Americans (or 2% of the population) live with disabilities resulting from TBI. Among OEF/OIF Veterans, TBI incidence estimates as high as 23% have been reported, with mild TBI (mTBI) being the most common.1 This proposal addresses the recommendations of the consensus of scientific conferences by aiming to develop a biomarker of traumatic cerebrovascular injury (TCVI) which can be useful in clinical trials of therapies.

Substantial data point to traumatic cerebrovascular injury (TCVI) underlying a significant portion of TBI-related disability. 2 The cerebral vasculature is a highly plastic tissue making TCVI an attractive target for therapeutic intervention after TBI. Preliminary studies indicate that PDE5 inhibitors such as sildenafil (Viagra®) show promise as treatment for cerebrovascular dysfunction after TBI. 3,4

The investigators adapted MRI-Blood Oxygenation Level Dependent (BOLD) with hypercapnia challenge, to the portable, less expensive, office-based Near InfraRed Spectroscopy (NIRS) technology and incorporated hypercapnia challenge as the functional challenge with NIRS.

MRI- BOLD BOLD (with 5% carbon dioxide (CO2) hypercapnia challenge via the Douglas Bag method) and fNIRS (also with 5% CO2 hypercapnia challenge via the Douglas Bag method) in traumatic brain injury (TBI) and healthy controls. The complementary methods give similar results with a high degree of correlation in TBI patients compared to healthy controls. 5 Nitric Oxide (NO), the primary endogenous vasodilator in the brain, plays a prominent role. Specific PDE5 inhibitors have come into widespread use, the first is Sildenafil (Viagra®) for the treatment of erectile dysfunction and primary pulmonary hypertension. The beneficial effect of sildenafil is related to increased local CBF and enhanced neurogenesis, vasculogenesis, and axonal remodeling in the peri-infarct zone. 6-9 To date, there have been no longitudinal studies of CVR using functional NIRS from the acute to the subacute/chronic stages of TBI in humans.

Objectives of this study:

1. To measure over time brain blood flow using fNIRS (using lights on the scalp) with hypercapnia challenge (like breath holding for about a minute at a time) in 30 people who have had a brain injury, moderate and severe patients, and compare it to that of 10 age-matched uninjured controls, starting as early as within 29 days of injury with the goal of within 7 days and measuring each time at approximately 1, 3 and 6 months after injury to better understand the extent and timing of cerebrovascular reactivity (CVR) in the first 6 months after TBI.

2. To compare brain injury-related brain blood flow changes with clinical magnetic resonance imaging (MRI) and post-concussive symptoms measured by survey questionnaires, a neurologist's examination, testing to measure thinking ability, and learn about blood markers associated with traumatic brain injury.

3. To measure changes in CVR longitudinally before and after a single dose administration of a phosphodiesterase 5 inhibitor, sildenafil citrate, up to 4 study time points (first 29 days days and approximately 1, 3 and 6 months after TBI).

4. To compare CVR measurements by fNIRS versus BOLD MRI with hypercapnia challenge.

5. In conjunction with primary measurement of cerebrovascular reactivity using BOLD MRI, secondary measurement of cerebrovascular permeability will also be collected using DCE MRI.

Study Design The proposal is a 24-month project in which the investigators will conduct a prospective, longitudinal, observational study of up to 40 acute TBI patients and 10 healthy controls.

1. WRNMMC male and female military health care beneficiaries (active duty, veterans or DEERS eligible) aged 18 to 55 years, presenting with a diagnosis of moderate or severe (DoD criteria) traumatic brain injury (TBI) and healthy volunteers aged 18 to 55 years.

2. Study participants at WRNMMC will be recruited from eligible military healthcare beneficiaries presenting to the WRNMMC ED or admitted to WRNMMC for TBI within 1 week of injury (most through TBI inpatient consult service and likely on trauma surgery, neurosurgery, orthopedics, neurology, PMR and/or internal medicine inpatient services).

Procedures:

Participants will sign a consent form, attend scheduled visits, and be paid $50 for each blood sample collected from participants at each of the up to 4 visits over a 6 month period.

Participants will have an inverview about their injury and medical history and examination by a study physician, have a urine pregnancy test (if applicable), complete some questionnaires, have some memory and thinking tests, give a blood sample, and do some imaging.

Imaging Magnetic Resonance Imaging (MRI). One MRI before and after about 45 minutes of one dose of sildenafil 50mg. Each imaging session will use hypercapnia using a Douglas bag, equipped with a switch to allow rapid shifting every minute from room air to 5% CO2 mixed with room air over 7 minutes. This kind of imaging will be done at 2 or 3 of the visits. The 29-day visit is optional, so if the participant's first visit is at the 30-day visit they will have imaging at that visit and then again at the 6-month visit. No imaging at the 90-day visit.

- Also common TBI MRI techniques will be performed (e.g. high-resolution 3D T1-weighted, T2, T2*, diffusion tensor imaging, arterial spin labeling), as well as the following sequences:

- Dynamic contrast-enhanced (DCE) MRI with intravenous gadolinium-based contrast agents (GBCAs) Participant goes to Radiology and gets heplock, etc. (pregnancy test if female)

Structural MRI

Participant comes out of scanner to place oral piece/noseclip for MRI-BOLD c hypercapnia.

Quick T1 for co-registration, then MRI-BOLD c hypercapnia challenge (10-15 min) Participant comes out of the scanner and takes mouthpiece/nose clip off. Next,DCE sequence, the participant is injected with the contrast agent through a heplock/iv in the scanner and the sequence takes about 15 min.

TOTAL scanner time is approximately 75-90 min.

Functional near infrared spectroscopy (fNIRS) will be be performed twice at each study visit, once before and once about 45 minutes after single dose administration of sildenafil 50 mg.

Study Medication

The study medication is used to activate a change in brain blood flow during the observation and measurement of cerebrovascular reactivity.

The study drug will be sildenafil citrate (Viagra®, Pfizer. Inc.). For this study, the investigators will use 50 mg tablets for the single dose administration at each visit.

Collection of Human Biological Specimens

Serum and plasma (5 ml each) will be collected at at each study visit (10 ml per visit or up to 40 ml over the 180 day course of the study).

Length of participation in the study: Participants enrolled in the TBI Group will have up to four study visits over a period of approximately 6 months and be enrolled for that length of time. Non-TBI Control participants require only a single visit and will be discharged from the study after their study visit is complete and results have been recorded.

Risks and Discomforts

fNIRS with hypercapnia challenge

The investigators anticipate the following non-serious adverse events (likely, with event rate < 5%):

1. Slight discomfort from the NIRS band on the head

2. Minor warmth under the band from the light emitters after ~ 30 minutes of testing

3. Anxiety and/or panic attack during hypercapnia challenge

4. Headache during/after hypercapnia challenge.

However, there are well recognized adverse effects. The following lists the adverse events reported by at least 2% of patients taking sildenafil in flexible dose Phase 2/3 studies, and were more common at the 100 mg dose than at lower dose than this study will be using.

Adverse events attributed to sildenafil in placebo-controlled randomized trials Adverse Event % of patients on sildenafil reporting AE (n = 734) % of patients on placebo reporting AE (n = 725) Headache 16% 4% Flushing 10% 1% Dyspepsia 7% 2% Nasal Congestion 4% 2% Urinary Tract Infection 3% 2% Abnormal vision* 3% 0% Diarrhea 3% 1% Dizziness 2% 1% Rash 2% 1%

*Abnormal Vision: Mild and transient, predominantly color tinge to vision, but increased sensitivity to light or blurred vision. In these studies, only one patient discontinued due to abnormal vision.

Orthostatic hypotension is an infrequent adverse effect of sildenafil therapy. VIAGRA doses above 25 mg should not be taken within 4 hours of taking an alpha-blocker.

Study participants will also be given the contact information for one of the study investigator physicians.

Neurocognitive tests Testing is critical for studying the effect of TBI on memory, behavior and functioning. All testing will be performed by a trained research assistant or psychometrist. No serious adverse events are anticipated.

Boredom Fatigue Frustration

Phlebotomy

Trained study personnel will draw 10 ml (2 teaspoons) at each study visit. Possible non-serious adverse events:

Bleeding Bruising Infection

Magnetic Resonance Imaging:

MRI has been safely performed in millions of persons; research subjects will be screened for metallic foreign bodies or other contraindications, similar to all clinical patients. Pregnant females will also be excluded from participating in these research MRIs.

Subjects may experience discomfort or anxiety while lying in the magnet and may communicate with the MRI technologist. Participants will have hearing protection.

Gadolinium-Based Contrast Agents:

Risks include local side effects from IV placement and contrast injection, systemic reaction to the MR contrast agents (less common than with CT contrast agents), and a rare but serious disease called nephrogenic systemic fibrosis (NSF).

There have been more recent descriptions of gadolinium deposition in the brain after exposure to MR contrast agents. The clinical significance (if any) of this discovery is currently unknown.

Subject Withdrawal

As stated in the consents, and as will be explained to the subjects, subjects may withdraw their participation from the study, at any time, without explanation. The procedure for withdrawal is stated in the consent document.

Privacy

All screening and enrollment procedures will be conducted in the study site clinics. All recruitment and subsequent study-related activities involving face-to-face interactions with subjects will be conducted in a private, closed-door office setting. All telephone contacts will be carried out in a closed room.

Confidentiality Protection

Each subject will be assigned a numerical code for identification purposes pertaining to data and biospecimens. The numberical code will contain no identifiers (numerical code only). A computer file linking subjects to their assigned numerical code will be safely stored as an encrypted file on a password protected computer. Paper records will be stored in locked cabinets in locked office space. Linking files will be kept for the life of the study and then destroyed. No subject will be identified in future publications as having taken part in this study.

Study Design

Conditions

Traumatic Brain Injury

Intervention

Sildenafil Citrate 50Mg Tab, functional Near-infrared Spectroscopy (fNIRS), Carbon Dioxide (CO2) 5%, Neuropsychological Assessments, Gadolinium contrast infusion, Blood sample collection for research purposes, Structural brain Magnetic Resonance Imaging (

Location

Walter Reed National Military Medical Center
Bethesda
Maryland
United States
20889

Status

Recruiting

Source

Uniformed Services University of the Health Sciences

Results (where available)

View Results

Links

Published on BioPortfolio: 2019-08-20T20:17:08-0400

Clinical Trials [1172 Associated Clinical Trials listed on BioPortfolio]

Non-invasive Measurement of Cerebrovascular Reactivity After Traumatic Brain Injury

The investigators will longitudinally measure cerebrovascular reactivity (CVR) by functional near-infrared spectroscopy (fNIRS) in acute (≤3 days from injury), subacute, and chronic phas...

Cerebrovascular Reactivity in American Football Players

Investigators will measure cerebrovascular reactivity (CVR) using functional near-infrared spectroscopy (fNIRS) and magnetic resonance imaging (MRI) during the chronic phase after repetiti...

Frontal Lobe Oxyhemoglobin Levels in Patients With Lower Extremity Burns Assessed Using a fNIRS

Investigators investigate the patterns of cortical activation using the NIRST in patients with peripheral neurological injury caused by lower extremity burns.

To Assess The Efficacy and Safety Of Oral Sildenafil in the Treatment of Pulmonary Arterial Hypertension.

To demonstrate a dose response for 1 mg, 5 mg and 20 mg TID oral sildenafil for the treatment of subjects with PAH.

Using Imaging to Assess Effects of THC on Brain Activity

To assess effects of THC (n=150) and THC + alcohol (n =50) in MJ users on prefrontal brain activity with functional near infrared spectroscopy (fNIRS) during resting state and during memor...

PubMed Articles [10644 Associated PubMed Articles listed on BioPortfolio]

Methodological Approaches and Recommendations for Functional Near-Infrared Spectroscopy Applications in HF/E Research.

The objective of this study was to systematically document current methods and protocols employed when using functional near-infrared spectroscopy (fNIRS) techniques in human factors and ergonomics (H...

Prediction of epileptic seizures with convolutional neural networks and functional near-infrared spectroscopy signals.

There have been different efforts to predict epileptic seizures and most of them are based on the analysis of electroencephalography (EEG) signals; however, recent publications have suggested that fun...

Exploring brain functions in autism spectrum disorder: A systematic review on functional near-infrared spectroscopy (fNIRS) studies.

A growing body of research has investigated the functional development of the brain in autism spectrum disorder (ASD). Functional near-infrared spectroscopy (fNIRS) is increasingly being used in this ...

Conducting Hyperscanning Experiments with Functional Near-Infrared Spectroscopy.

Concurrent brain recordings of two or more interacting persons, an approach termed hyperscanning, are gaining increasing importance for our understanding of the neurobiological underpinnings of social...

Investigation of the sensitivity-specificity of canonical- and deconvolution-based linear models in evoked functional near-infrared spectroscopy.

Functional near-infrared spectroscopy (fNIRS) is a noninvasive brain imaging technique to measure evoked changes in cerebral blood oxygenation. In many evoked-task studies, the analysis of fNIRS exper...

Medical and Biotech [MESH] Definitions

A PHOSPHODIESTERASE TYPE-5 INHIBITOR; VASODILATOR AGENT and UROLOGICAL AGENT that is used in the treatment of ERECTILE DYSFUNCTION and PRIMARY PULMONARY HYPERTENSION.

A noninvasive technique that uses the differential absorption properties of hemoglobin and myoglobin to evaluate tissue oxygenation and indirectly can measure regional hemodynamics and blood flow. Near-infrared light (NIR) can propagate through tissues and at particular wavelengths is differentially absorbed by oxygenated vs. deoxygenated forms of hemoglobin and myoglobin. Illumination of intact tissue with NIR allows qualitative assessment of changes in the tissue concentration of these molecules. The analysis is also used to determine body composition.

A spectroscopic technique in which a range of wavelengths is presented simultaneously with an interferometer and the spectrum is mathematically derived from the pattern thus obtained.

Measurement of the regional temperature of the body or an organ by infrared sensing devices, based on self-emanating infrared radiation.

Spectroscopy technique which measures changes in organic compounds by tracking the spectral energy of absorption of HYDROGEN atoms.

More From BioPortfolio on "Cerebrovascular Reactivity Assessed With fNIRS as a Biomarker of TCVI After Acute Traumatic Brain Injury in Military"

Quick Search

Relevant Topics

Anxiety Disorders
Anxiety is caused by stress. It is a natural reaction, and is beneficial in helping us deal with tense situations and pressure. It is deterimental when is becomes an excessive, irrational dread of everyday situations. The most common types of anxiety di...

Radiology
Radiology is the branch of medicine that studies imaging of the body; X-ray (basic, angiography, barium swallows), ultrasound, MRI, CT and PET. These imaging techniques can be used to diagnose, but also to treat a range of conditions, by allowing visuali...

Vascular
Vascular relates to blood vessels (Oxford Medical Dictionary) and can be used to describe the supply of blood, a disease affecting the blood vessels or molecules associated with these structures. For example, <!--LGfEGNT2Lhm-->atherosclerosis ...


Searches Linking to this Trial