Active clinical trials for "Constriction, Pathologic"

Confocal endomicroscopy is an emerging technique that allows in vivo imaging of cells and tissue structures of the gastrointestinal mucosa, with a magnification of about 1000 times, guiding optical biopsies in real time. Confocal endomicroscopy represents technique that combines conventional white light image with the confocal microscope probe, thereby allowing examination of the surface epithelium in vivo and histological diagnosis during endoscopy. Among the applications already established for its use, stand out diagnosis of Barrett's esophagus, gastric atrophy and intestinal metaplasia, celiac disease, differentiation of hyperplastic adenomatous polyps of the colon, microscopic colitis and follow-up of patients with inflammatory disease, reducing the need for endoscopic biopsies. The CLE can still detect molecular changes effectively improving the endoscopic diagnosis. This pilot project consists of 07 subprojects which the technology of confocal endomicroscopia will be evaluated and compared with the histological results of biopsy or surgical specimens: 1. confocal endomicroscopy for the diagnosis of high-grade dysplasia and superficial esophageal adenocarcinoma in patients with Barrett's esophagus 2 Diagnosis of superficial esophageal squamous cell carcinoma in patients with head and neck cancer by confocal endomicroscopy 3 Detect the presence of premalignant lesions in the gastric stump in patients with reflux alkaline gastritis after partial gastrectomy 4. detect lesions in the gastric mucosa of patients with familial history of gastric cancer 5 Biliary Strictures: differential diagnosis by confocal endomicroscopia 6 confocal Endomicroscopy of cystic neoplasms of the pancreas 7 Contribution of confocal endomicroscopy for the differential diagnosis of colorectal polyps The project aims to deploy the structure of the Confocal endomicroscopy Endoscopy ICESP, for performing in vivo histological examinations of the digestive tract, biliary tract and pancreas. All research groups involved in the early detection of tumors of the esophagus, stomach, biliary tract, pancreas, colon and rectum may benefit from the implementation of this methodology.

The purpose of this study is to evaluate the safety and performance of the HLT System in patients with severe aortic stenosis who present at High Risk for aortic valve replacement surgery.

The aim of this study is to determine whether optimal medical treatment can postpone carotid endarterectomy.

Coronary artery blockages can reduce blood flow to the heart muscle. Fractional flow reserve (iFR or FFR) assessment is an invasive tool used to determine how much blood flow is reduced. The investigators will perform iFR/FFR on all intermediate coronary stenoses using standard practice, immediately before (at the time of) transcatheter aortic valve replacement (TAVR) and after successful TAVR. The investigators will compare pre- and post-TAVR iFR/FFR values, and assess short-term outcomes. The investigators hypothesize that iFR/FFR values will be consistently and significantly higher pre-TAVR in comparison with post-TAVR for the same lesions.

This study will enroll patients who are referred for coronary angiography and require physiological assessment to see if the lesion can be treated as per the local standard of care. Approximately 92 participants will be enrolled. There are no follow up visits required so participation in this study will end when subjects are discharged from the hospital.The study will be comparing the resting flow reserve against the instantaneous wave-free ratio (iFR) and fractional flow reserve. All these tests offer a way to image a legion and determine if it is suitable to be treated. FFR measures the pressure differences across (narrowed coronary arteries usually due to atherosclerosis), iFR's are performed during cardiac catheterisation (angiography) using invasive coronary pressure wires which are placed in the arteries of the heart that are to be assessed and the Resting flow reserve looks at the maximum increase in blood flow through the coronary arteries above the normal resting volume.

To collect information about the management of symptomatic severe Aortic Stenosis (AS) and Aortic Regurgitation (AR) using transcatheter aortic valve replacement (TAVI).

CAPTIVA-MRI is an observational multimodal MR imaging study that is ancillary to the CAPTIVA trial [a 3-arm, double-blind Phase III trial conducted at approximately 115 StrokeNet sites randomizing patients with stroke attributed to 70-99% intracranial atherosclerotic stenosis (ICAS) to aspirin plus ticagrelor, clopidogrel, or rivaroxaban.] The primary goal of this ancillary study is to determine if MRI biomarkers can potentially identify ICAS patients who fail best medical management. The CAPTIVA-MRI study leverages the CAPTIVA trial design and implementation to capture information that will inform and facilitate the next generation of ICAS trials and the management of patients with ICAS.

Intracranial artery stenosis (ICAS) is a leading cause of ischemic stroke worldwide, contributing to the global burden of stroke, particularly in the Asian population. However, there is no non-invasive, easy to popularize and economic for intracranial artery stenosis in mass population screening. This study aims to evaluate the predictive value of retinal vascular signs for intracranial artery stenosis (ICAS) and explore a new screening method.

The purpose of this study is to investigate the ability of the compound[F-18]RGD-K5, when used as a tracer during PET (positron emission tomography) imaging, to detect regions of unstable atherosclerotic plaque in the carotid artery of subjects being considered for carotid endarterectomy (CEA),and to confirm this ability through histological studies of samples of carotid artery plaques that will be collected during the planned carotid surgery.

Pyelo-ureteral junction syndrome is the most common urological abnormality in children. Functional MRI has been evaluated several times, and had shown good correlation with scintigraphy, but tends to over estimate results. Moreover, those studies included a small number of cases. Its sensitivity to detect crossing polar vessel is limited. We aimed to evaluate, in patients between 0 and 1 year old, the correlation between MRI and scintigraphy differential renal function. Our secondary objectives are : evaluation of MRI performances to detect polar vessel ; comparison of surgery times depending of MRI only realisation or MRI and scintigraphy realisation.