28 Clinical Trials for Various Conditions
In this study the investigators plan to enroll a total of 25 evaluable volunteers (volunteer population) for the development and optimization of perforator imaging protocols and 50 evaluable clinical patients receiving flap procedures at OSUMC for the clinical validation of the optimized protocol. No extrinsic MR contrast agent will be injected. Clinical patients' MRI images will be evaluated independently by radiologists and plastic surgeons and compared to the clinical CTA images.
This proposal is based on findings from our previous work involving ferumoxytol-enhanced cardiac magnetic resonance angiography. The resolution of the pulmonary vasculature based on our previous imaging protocol was exceptional (PMID: 26786296). In the Partners Healthcare System between January 1, 2014 and January 1, 2015 there were 541 patients evaluated in Partners Healthcare-affiliated hospitals with a diagnosis of pulmonary embolism and acute or chronic kidney disease at the same visit between 01/01/2014 and 01/01/2015. Ventilation perfusion scanning was performed in 201 patients during this same time interval. Up to 63% of these patients in one year did not receive the diagnostic test of choice.
To systematically develop, test, and refine peripheral vascular electrocardiography-gated fast spin echo magnetic resonance imaging for the accurate diagnosis of peripheral arterial disease without gadolinium contrast. To test prospectively the accuracy of fast spin echo in peripheral arterial disease patients, compared with bolus-chase and time-resolved gadolinium enhanced magnetic resonance angiography. Additionally, as a substudy of this project, we will compare our fast spin echo approach with alternative non-contrast-enhanced magnetic resonance imaging methods such as time-of-flight and steady-state gradient echo imaging. The overarching goals of our research are to develop and validate a peripheral magnetic resonance imaging technique that accurately depicts anatomy and disease without exposing patients to exogenous contrast material and its associated risks.
The purpose of the study is to create MR images using an investigative technique called pulse sequences with new computer software programs. The sequence will allow us to image vessels without injecting contrast agents.
The overall objective of this proposal is to examine the feasibility and accuracy of non-contrast magnetic resonance angiography (MRA) to comprehensively evaluate individuals referred for transcatheter aortic valve implantation (TAVI).
The study will evaluate the efficacy and safety of Dotarem enhanced MRA in patients suffering from carotid or vertebral arterial disease.
The study will evaluate the efficacy and safety of Dotarem enhanced MRA in patients suffering from carotid or vertebral arterial disease.
The study will evaluate the efficacy and safety of Dotarem enhanced MRA compared to TOF MRA in patients suffering from renal arterial disease.
The study will evaluate the efficacy and safety of Dotarem enhanced MRA compared to TOF MRA in patients suffering from renal arterial disease.
The purpose of this study is to compare the difference between two magnetic resonance imaging (MRI) techniques for visualizing arteries. The study hypothesizes that one method that relies upon imaging flowing blood in the pelvic and leg arteries will not be as accurate or efficient as injecting a safe imaging agent to change the appearance of the blood on the MRI. Both methods will be compared with Digital Subtraction Angiography (DSA).
This study will determine the usefulness of magnetic resonance imaging (MRI) for examining the heart or blood vessels. MRI uses a magnetic field and radio waves to produce images of body tissues and organs. The subject lies on a table that can slide in and out of the scanner (a metal cylinder), wearing earplugs to muffle loud noises that occur during the scanning process. MRI of the heart and blood vessels, called magnetic resonance angiography (MRA), is a developing diagnostic method that permits evaluation of arteries and veins without the use of x-rays or invasive catheterization required by conventional angiography. People 18 years of age and older with known or suspected atherosclerotic disease may be eligible for this study. Participants have blood tests and MRA scanning. The MRA takes about 1.5 to 2 hours. During part of the scan, a contrast agent may be injected into a vein to brighten the images of the heart and blood vessels. Subjects are monitored with an electrocardiogram and are asked to hold their breath for about 5 to 20 seconds intermittently during the procedure. A CT scan may be done to confirm the MRA findings. CT uses x-rays to produce pictures of the heart and blood vessels. The subject lies on a bed during the scan and is given a contrast agent through a catheter inserted into a vein. Subjects are asked to hold their breath intermittently for about 5 to 20 seconds. A medicine called a beta blocker may be administered to slow the heart rate.
This study will evaluate ways to improve magnetic resonance angiography (MRA) for diagnosing atherosclerosis (hardening and narrowing of the arteries). MRA is a new method for looking at arteries and veins without standard angiography, which requires inserting a catheter into a blood vessel, injecting a contrast material, and obtaining X-ray images. Current MRA techniques, however, do not depict the lumen (cavity) of small vessels well enough to accurately determine the extent of their narrowing. This study will test image processing methods with the eventual goal of improving MRA accuracy to the point that it can replace X-ray catheter angiography for diagnosing atherosclerotic disease. Patients with atherosclerosis who have had conventional angiography at Suburban Hospital in Bethesda, MD, may be considered for this study. They will be screened with a brief history and physical examination, and those enrolled will have a MRA scan within 72 hours of their conventional angiogram. For this procedure, a catheter is placed in a vein in the patient's arm and the patient lies on a table that slides into a magnetic resonance imaging (MRI) scanner-a large donut-shaped machine with a magnetic field. Surface coils-flexible, padded antennae used to improve the quality of the pictures-are wrapped around the patient's legs. At times during the scan, the patient is asked to hold his or her breath for several seconds, and a contrast material called gadolinium is injected through the catheter in the vein. This substance enhances the images of blood flow in the vessels. The procedure generally takes about an hour and a half, although the actual imaging takes only a small part of that time.
Magnetic Resonance Angiography (MRA) is a method used to evaluate arteries and veins without the use of invasive catheters or x-rays (radiation). MRA technique has been continuously improving and has become more accurate at diagnosing problems of narrowing in blood vessels. However, MRA has a difficult time detecting narrowing in small blood vessels, limiting its use to large arteries. The purpose of this study is to recruit patients diagnosed with or suspected of having, atherosclerosis (hardening of the arteries) to participate in a series of new state-of-the-art diagnostic tests using MRA. This study is a combined effort between the National Institutes of Health (NIH), Uniformed Services University of the Health Sciences (USUHS), and General Electric Medical Services and is supported a Cooperative Research Agreement is to (CRADA). The goal of this study is to improve MRA to the point that it can reliably replace diagnostic x-ray catheter angiography in the evaluation of patients with atherosclerosis.
Magnetic resonance imaging (MRI) is a diagnostic tool that creates high quality images of the human body without the use of X-ray (radiation). MRI is especially useful when studying the arteries of the heart (CMRA, coronary magnetic resonance angiography). In this study researchers from several laboratories and hospitals will work together to determine the safety and effectiveness of CMRA with MS-325. MS-325 is a contrast agent. It is given to patients undergoing CRMA in order to improve the appearance of the arteries of the heart.
Magnetic resonance coronary angiography (MRCA) has its advantage in its ability to assess the coronary artery morphology without radiation or contrast media. The clinical application of MRCA is still challenging mainly because of technical limitations such as: its time-consuming image acquisition, inconsistent image quality, and low spatial resolution. Optimization of MRCA image acquisition method is in progress and compressed sensing (CS) with post-processing (de-noising) by deep learning reconstruction (DLR) is promising to solve these problems. The lack of a consensus method to assess the coronary stenosis on MRCA is another issue. Generally, a stenosis in MRCA is observed as a signal intensity (SI) drop along the artery compared to the healthy segments. A previous study has reported from its comparison of MRCA with coronary angiography (CAG) that the SI drop of 35% in MRCA stenosis lesion corresponded to the significant stenosis in CAG. Although this SI drop phenomenon was not observed in a different study on chronic total obstruction cases. One of the hypothesized reasons is that the SI drop in MRCA is affected not only by the stenosis severity but also the plaque characteristics, which is not assessable by CAG. To investigate this hypothesis coronary CTA is needed, which is a robust modality to assess coronary stenosis and plaque characteristics. Comparison between MRCA with CTA has the potential to give better information for developing a robust method to assess MRCA. In this study, the investigators aim to evaluate the feasibility of MRCA scanned with optimized protocol and post-processing, and to develop robust coronary artery assessment method on MRCA, by comparison with clinical coronary CTA.
In Contrast-Enhanced Magnetic Resonance Angiography (CE-MRA) a contrast agent is injected into an arm vein using a programmable medical device called a power injector. Once the contrast has circulated to the blood vessel of interest they can be imaged with MRI and distinctly separated from surrounding non-vascular tissue. This project is designed to find the best way to administer the contrast agent during CE-MRA to produce the best images. The clinical availability of programmable power injectors facilitates the use of variable contrast rate and volume injection protocols that are based on patient specific parameters. CE-MRA is a valuable imaging tool for diagnosing abnormalities of the major blood vessels in the chest and abdomen. It is often used in conjunction with cardiac magnetic resonance (CMR) examinations to evaluate the blood vessels of the heart and lung. CE-MRA is attractive because 1) it does not involve radiation, and 2) the contrast agents used are not toxic to the kidneys and can be used in patients who are at greater risk for kidney dysfunction following iodinated contrast agents. We plan to administer a small (1cc) test amount of contrast, taking pictures as the contrast passes through the blood vessels, and analyze the results. Using this information, we will administer an individually patient-tailored injection given in multiple phases (i.e., a "multi-phasic" injection) to maintain constant contrast concentration (and therefore constant signal intensity) throughout the scan. We believe this will reduce image blurring, and improve the sharpness and likely the diagnostic quality of CE-MRA.
Infiltration of a surgically-placed hemodialysis vascular access (HVA) is recognized as a major contributor to the high hospital re-admission rate in dialysis-dependent patients. Three dimensional modeling has been demonstrated as a critical tool for procedurists in preparation for surgical interventions but no such modeling is yet available for dialysis specialists to avoid the common complication of HVA infiltration. Contrast enhanced magnetic resonance angiography (MRA) can be used to generate a three dimensional image data that could render a three dimensional resin-based model of a vascular access.
Investigators at the Biomedical Imaging Research Institute (BIRI) at Cedars-Sinai Medical Center have developed a Magnetic Resonance Imaging (MRI) method for imaging coronary arteries using slow-infusion, contrast-enhanced data acquisition. This method allows faster data acquisition and better spatial resolution. Specific aims of this study are to: 1. compare coronary artery imaging with and without contrast media on both healthy subjects and patients; 2. assess the accuracy of coronary MRI in detecting coronary artery disease as compared to conventional x-ray angiography Researchers hypothesize that contrast-enhanced MRI will improve the delineation of coronary arteries over non-contrast-enhanced MRI and that optimized, contrast-enhanced coronary MRI technique will accurately detect coronary artery disease (CAD) as compared to conventional x-ray angiography.
This is a pilot study to determine whether coronary magnetic resonance angiography(CMRA)can identify adverse plaque characteristics (buildup of fat, cholesterol, calcium, and other substances found in the blood) seen on coronary computed tomography angiography(CCTA) and evaluate whether there is a relationship between the adverse plaque characteristics and the presence of coronary artery wall inflammation.
Subjects referred for a routine CTA (computed tomography angiography) or MRA (magnetic resonance angiography) will be invited to participate in the study and subjects will be involved in the study for between 2 and 12 days. Two to three visits to the study doctor will be required. This study will compare the diagnostic results of Gadobutrol enhanced MRA images with MRA images taken without contrast agent using images from a CTA as the standard of reference, which may have been performed up to 60 days prior to enrolment. If a CTA has not been performed in this prior time period, a CTA is required for the study. MRA and CTA images will be collected for an independent review (blinded read).
Patients with blockage of the blood vessels that supply blood to the back of the brain, known as vertebrobasilar disease (VBD), are at risk of having a stroke or temporary symptoms of a stroke known as transient ischemic attack (TIA). The risk of repeated stroke associated with VBD may be affected by several risk factors, including the degree to which the blockage reduces the blood flow to the brain. Patients with VBD have different levels of blockage ranging from partial blockage to complete blockage, which can affect the blood flow to the brain by variable amounts. The purpose of this research is to determine if patients with symptomatic VBD who demonstrate low blood flow to the back of the brain on magnetic resonance (MR)imaging are at higher risk of developing another stroke or TIA than patients with normal blood flow.
Renovascular hypertension (RVH) is a potentially curable disease affecting 0.5-5 percent of patients with hypertension. The current diagnostic work-up of RVH involves a complex algorithm which includes doppler ultrasound, captopril renography and conventional angiography. Because of the expense, risk and inconvenience of this workup, patients may not be correctly diagnosed. Advances in MR technology present the opportunity to develop a single comprehensive test. This would combine an MR angiogram that provides anatomic information about the renal arteries, and an MR renogram that provides information about the functional impact of a stenosis as a cause of hypertension. Our main purpose is to test MR renography with and without an oral angiotensin converting enzyme inhibitor (ACEI) combined with MR angiography against the reference standard of captopril radionuclide renography. Secondary goals of this study are to test whether hypoxia within ischemic kidneys affected by RVH is detectable by T2 weighted (Blood oxygen level dependent or BOLD) MRI. This is considered of value since such a test of oxygenation would further shorten and simplify the diagnostic MR test. Information gained from this study could lead to important changes in the diagnostic and pathophysiologic understanding of RVH.
This study is designed to evaluate the effectiveness and measurable cost impact of stress cardiac MRI for non-invasive evaluation of intermediate lesions discovered on CCTA in low-to-intermediate risk patients admitted to the ED with suspected ACS. Our primary objective is to determine if the strategy of CTA + stress CMR will reduce the length of time in the ED required to establish a definitive diagnosis, compared to CTA + stress MPI.
This study examines the relationship between angiographic coronary collaterals (Rentrop grades) and post-reperfusion microvascular injury. This study aims to assess the impact of coronary collateral circulation on intramyocardial hemorrhage incidence and extent.
The investigators intend to examine the effects of ocrelizumab use in African American multiple sclerosis disease course compared to Caucasian disease course utilizing imaging measures with magnetic resonance imaging (MRI) and optical coherence tomography angiography (OCT-A)..
The purpose of this study is to examine small vessel disease (a condition in which the small arteries in the heart become narrowed). The investigators want to know how the small vessel disease contributes to pre-HFpEF (a condition with inadequate heart muscle function in the setting of preserved muscle pumping) and to better identify potential treatment for prevention of HFpEF. The main procedures of this study include up to 2 clinic visits (initial visit and a second clinical visit only if participants are unable to complete all research procedures at the initial visit); a 6-week phone interview visit, 4 quarterly follow-up phone interview visits in year 1; year 1 follow up cardiac MRI based on availability and ongoing annual follow-up phone interview visits to track progress. If participants choose to take part in this study, participants direct participation will end after 1 year, participants will then have the option of participating in ongoing annual check-in calls. Participants will be asked to undergo a physical exam and provide a completed medical history; complete a Cardiovascular (or Cardiac) Magnetic Resonance Imaging (CMRI) with contrast agent; complete questionnaires to describe heart symptoms and overall quality of life status; undergo blood draws to provide blood samples for research testing, and allow the study team to have access to medical records.
The Women's Ischemia Study Evaluation (WISE), a cohort study of over 1000 women, has made many contributions to the understanding of cardiovascular disease. A milestone acknowledged in the 2011 AHA Herrick Lecture is the role of Coronary Microvascular Dysfunction (CMD) in women with symptoms/signs of ischemia without obstructive coronary artery disease (CAD). While in 1996, CMD was considered "an imaging artifact", in 2013, it is a widely accepted as a pathophysiologic process requiring systematic cohesive scientific pursuit. CMD is prevalent, associated with adverse clinical outcomes, poor quality of life and healthcare costs rivaling obstructive CAD. There are 2-3 million US women with CMD, and 100,000 new cases projected annually placing CMD prevalence, morbidity and costs higher than all female reproductive cancers combined. Among women with ischemia, preserved ejection fraction and no obstructive CAD, it has been observed that there are relatively more new onset heart failure (HF) hospitalizations than nonfatal myocardial infarction (MI). It has been hypothesized that CMD contributes to left ventricular (LV) diastolic dysfunction and subsequent heart failure with preserved ejection fraction (HFpEF). Preliminary data further suggests that left ventricular diastolic dysfunction is linked to CMD via a mechanism of augmentation and/or perpetuation by cardiomyocyte fat accumulation. HFpEF is prevalent in women and older men, but poorly understood. Mechanistic understanding is critical to HFpEF intervention and guideline development. The study hypotheses are as follows: 1. Risk factor conditions (hypertension, dyslipidemia, dysglycemia, loss of estrogen) promote an inflammatory and pro-oxidative state making the microvasculature vulnerable; 2. Vulnerable coronary microvasculature becomes dysregulated (sympathetic nervous system activation, endothelial dysfunction, changes in vascular smooth muscle activation, spasm) causing repeated episodes of transient ischemia; 3. Repeated ischemia-reperfusion episodes facilitate preconditioning with preservation of cardiomyocyte contractile and microvascular function against ischemic injury; 4. Ischemia-reperfusion and preconditioning lead to cardiomyocyte fat accumulation and relaxation impairment resulting in diastolic dysfunction and heart failure with preserved ejection fraction (HFpEF).
Tumors of the spine can be described as primary, meaning that the tumor originated from cells normally found in the spine, or metastatic, cells from another area of the body that have spread to the spine. Metastatic tumors are more common than primary tumors. Tumors of the spine can press against the spinal cord and interfere with information traveling down from the brain to the nerves of the spinal cord. As a result, patients with spinal tumors can suffer from loss of movement and sensation within areas of the body below the tumor. In addition, tumors of the spine are typically painful conditions. Presently, the treatment of choice for spinal tumors is radiation therapy. However, many tumors of the spine become resistant to radiation therapy. In addition, because the spinal cord is often so close to the tumor it can be damaged by the radiation. Absolute (100%) ethanol is commonly known as "alcohol". It is the same kind of alcohol found in alcoholic beverages. When pure alcohol is injected directly into a tumor it can destroy cells and blood vessels. Because of this feature, researchers would like to test the effectiveness of alcohol in treating patients with spinal tumors. Researchers believe that intratumoral ethanol injection is a treatment worth studying more closely because it is minimally invasive, has been proven to be an effective treatment for other types of metastatic tumors, can be used repeatedly, and does not interfere with other treatments such as surgery. In addition to testing the effectiveness of intratumoral ethanol injection, this study will attempt to determine the causes of pain associated with spinal tumors.