14 Clinical Trials for Various Conditions
The clinical and demographic characteristics of patients undergoing transcatheter aortic valve implantation (TAVI) pose unique challenges for coronary computed tomography (CT) imaging, as this patient population is mainly composed of elderly, frail individuals with severe aortic stenosis, multiple comorbidities, high prevalence of heavily calcified coronary artery disease (CAD) and revascularized coronary arteries. Such vulnerable patients could benefit from a more precise assessment and characterization of their CAD with ultra-high resolution (UHR) photon-counting detector (PCD) CT that would potentially avoid the need for pre-implantation invasive coronary angiography (ICA). This international multicenter prospective registry study aims to investigate the feasibility and diagnostic accuracy of PCD-CT in the assessment of CAD in the high-risk population of patients undergoing TAVI, as compared to ICA.
To compare the efficacy of 16-row multi-detector CT (MDCT) with standard myocardial perfusion imaging in detecting coronary artery disease (CAD) in patients without a previously established diagnosis of CAD.
The purpose of this study is to evaluate the investigators ability to obtain reliable and meaningful 11C-Choline PET-CT images of esophageal cancer.
The Cognitive Neuroscience Section of the National Institute of Neurological Disorders and Stroke proposes to continue its cross-sectional and longitudinal studies of cerebral metabolism in frontal lobe dementias and atypical basal ganglia disorders. These studies include repeated assessments of neuropsychological and brain anatomical and metabolic function in subjects with these important and possibly related brain disorders.
Background: * Computed tomography (CT) creates three-dimensional images based on X-ray imaging. CT is useful for determining treatment approaches for certain diseases, such as calcific aortic stenosis (narrowing of the aorta because of calcium deposits). * Comparing the data received from CT scans with the data received from heart catheterization (which assesses the heart's condition and function) can be used to improve treatment in patients with certain heart conditions. Researchers are interested in looking at the effectiveness of both procedures in assessing possible surgical treatments for patients with calcific aortic stenosis. Objectives: - To analyze cardiac CT scans in conjunction with existing heart scan results to improve treatments for future minimally invasive aortic valve replacement. Eligibility: - Patients 18 years of age and older who have been diagnosed with aortic valve stenosis that may be treated surgically, and who will undergo or have recently undergone heart catheterization. Design: * Participants will have a CT scan within 90 days of the medically necessary heart catheterization, but before any other surgical or catheter treatment. * During the CT scan, patients will be asked to hold their breath intermittently for about 5 to 20 seconds. Patients will be inside the scanner for less than 30 minutes. * Patients will be asked to return in 3 to 7 days for a blood test to check kidney function. * Researchers will analyze the results of the CT scan in conjunction with the previous results from the catheterization to determine possible improved treatment options.
To compare computed tomography (CT) images (pictures) of the coronary arteries using the General Electric (GE) LightSpeed VCT scanner with x-ray coronary angiography in patients with typical or atypical chest pain suspected of coronary artery disease (CAD).
This study will evaluate the effectiveness of a flexible belt device in guiding patient breathing during computed tomography (CT)-guided needle biopsy. When patients undergo CT scanning to help guide the physician during a tissue biopsy, they are usually asked to hold their breath while the scan is taken of certain parts of the body. When the first scan is completed, the patients are allowed to breathe, and are then asked to hold their breath again while the needle is advanced towards the tissue to be biopsied. Since body organs and tissues move with breathing, this study will try to stop the patient's breathing at the same place in the breathing cycle to ensure that the biopsy target stays still and in the same place. This study will see if the flexible belt, used with a computer screen that charts the patient's breathing, will improve the patient's ability to stop breathing at the same place in the breathing cycle before and during the biopsy. Patients 18 years of age and older who have a lesion requiring a needle biopsy in the chest or abdominal area may be eligible for this study. The biopsy procedure must require CT scan guidance. Participants will undergo the following procedures: * Breathing exercise: A flexible, loose-fitting belt is placed around the patient's abdomen and the patient is asked to stop breathing in the following ways: 1) take a deep breath in and hold; 2) breathe deeply out and hold; and 3) breathe regularly and hold. * Needle biopsy: The patient is positioned in a CT scanner and is asked to hold his or her breath while an initial scan is taken. Then the patient is taken out of the scanner and the place the needle entry site for the biopsy is marked on the skin. A local anesthetic is applied to the site and the patient is asked to hold his or her breath the same way as before. During this breath hold, the patient may or may not be shown a computer screen displaying a graph of the patient's breathing and the point in the cycle of the previous breath hold. The biopsy is then performed with CT guidance. While the CT pictures are being taken, the patient is again asked to breathe and hold his or her breath as before. When the biopsy is completed, the belt device is removed.
The investigators will be evaluating bone marrow composition via magnetic resonance imaging in adolescents diagnosed with cystic fibrosis (CF) compared to healthy, matched controls. The investigators will also be assessing their bone mineral density via other imaging modalities, including dual-energy X-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT). This longitudinal project will focus on abnormalities in bone marrow composition, and specifically whether adolescents with diagnosed with CF exhibit increased bone marrow fat, its association with bone mineral density (BMD) and the underlying pathophysiology, including glycemic control, inflammation, and bone turnover markers.
The investigators will be evaluating bone marrow composition via magnetic resonance imaging in newly diagnosed adolescents with Crohn disease (CD) compared to healthy, matched controls. The investigators will also be assessing their bone mineral density via other imaging modalities, including dual-energy X-ray absorptiometry and peripheral quantitative computed tomography. This longitudinal project will focus on abnormalities in bone marrow composition, and specifically whether adolescents with newly diagnosed CD exhibit increased bone marrow fat, its association with bone mineral density (BMD) and the underlying pathophysiology, including bone turnover markers and immune cellular/molecular parameters.
This is a randomized, double-blind, single dose, dose-escalation study to evaluate the safety, tolerability, and pharmacokinetics of NCTX (PEGylated Liposomal Iodixanol Injection) administered intravenously to healthy volunteers. In addition, computed tomography (CT) scans will be acquired to measure radiographic density in regions of interest (ROI) at times from 3-5 hours and up to 72 hours following NCTX administration.
The aim of this study is to develop an intervention that will produce a sustained improvement in physical activity and chronic stress as a means to slow the menopause-related accumulation of visceral adipose tissue in mid-life women.
The goal of this project is to compare visceral fat measurements derived from Lunar iDXA total body scans and from Computed Tomography (CT) scans of the abdominal region.
The goal of this study is to estimate how often pelvic fractures occur in women treated with radiation therapy for either newly diagnosed or recurrent cervical, endometrial, or vaginal cancer. The study will also estimate the changes in bone mineral density and the changes in the blood that relate to "bone turnover". High bone turnover can weaken bones and make you more likely to break a bone.
Primary Objectives: * To estimate and compare the sensitivity and specificity of computed tomography (CT), plain radiography (XR), and skeletal scintigraphy (SS) with each other for the assessment of response of bone metastasis in patients with breast cancer. * To estimate and compare the sensitivity and specificity of M. D. Anderson (MDACC) bone metastasis criteria with that of current criteria (UICC, WHO) in breast cancer patients for the assessment of the behavior of osseous metastasis in breast cancer patients. Secondary Objective: * To evaluate the progression free survival (PFS) and overall survival (OS) of each response group (CR, PR, SD, PD) assessed by imaging and response criteria.