Active clinical trials for "Constriction, Pathologic"

This study is designed to treat benign ureteral stricture with balloon dilatation through prospective multicenter studies. It aims to indications, procedure standards, and therapeutic effects of balloon dilation, and provide further guidance for endoscopic treatment of benign ureteral stricture.

Stenting for systematic Intracranial artery stenosis is challenged recently, especially for safety. This registry is aimed to explore the safety profile during peri-operation period in Stenting procedures for systematic Intracranial artery stenosis in Chinese population in real world.

The objective of this protocol is to establish a multicenter registry to evaluate the impact of radiofrequency ablation in the management of patients with pancreatico-biliary disorders including malignancies.

Observational registry including patients with peripheral artery disease due to femoro-popliteal stenosis or occlusion treated with cutting ballon- and subsequent drug-coated-ballon-percutaneous-transluminal-angioplasty (PTA).

The investigators aim to identify all clinical, biological, echo and imagistic parameters that predispose to increased progression rates in a prospective observational trial which will include ONLY patients with moderate AS, with the complete cardiological investigational tools provided in 2012. Once those parameters are found, medical and interventional treatment could be implemented to decrease the mortality rates.

Percutaneous epidural neuroplasty (PEN) is an effective interventional treatment for radicular pain. But in some cases with wire catheter like Racz catheter, contrast runoffs were not shown to the foramen. This study will show that contrast runoff will affect the results of PEN and in cases which contrast runoff are not shown, additional transforaminal epidural blocks will affect the results of PEN by reviewing medical record, retrospectively.

Coronary fraction flow reserve (FFR), the ratio of the mean coronary pressure distal to a coronary stenosis to the mean aortic pressure during maximal coronary blood flow (hyperemia), defines the hemodynamic significance of coronary artery narrowing. Noninvasive assessment of FFR via a combination of computational fluid dynamics (CFD) and coronary CT angiography CCTA (the so-called FFRCT) has potential. Coronary computed tomographic angiography is a noninvasive test for diagnosis of anatomic coronary stenosis (i.e., narrowing of a blood vessel). A new analytical model of FFR from the general Bernoulli equation (conservation of energy) (FFRB) is simple and has potential. A collaborator group has recently developed a new analytical model to quantify pressure drop, and hence FFR, based on lesion dimensions (i.e., the cross-section area along the lesion and the length of lesion) and coronary flow, with no empirical parameters. The investigators hypothesize that this new model will allow quantification of FFR (FFRB) in a cohort of human patients with intermediate coronary stenosis. The study will compare FFRB with invasive FFR measurements from invasive coronary angiography (ICAG).

To measure ligamentum flavum thickness in patients with different nationalities, sexes, heights, ages, and weights from Xinjiang Uygur Autonomous Region of China with CT, explore the correlation between various factors and ligamentum flavum thickness, provide reference for pedicle screw placement and lumbar decompression surgery, develop individualized surgical programs, and can effectively reduce the incidence of unnecessary postoperative complications induced by misplacement.

Revascularization of borderline coronary stenoses (40-70%) is usually driven by fractional flow reserve (FFR) which expresses the physiological significance of a lesion and tells the operator whether PCI may reduce the rate of adverse events as compared to medical therapy. Coronary stenoses with FFR value < 0.80 are indeed associated with a higher rate of adverse event and requires coronary revascularization whereas lesions with FFR > 0.80 show an excellent prognosis which cannot be improved by coronary stenting. Such a predictive value of FFR is theoretically based only on the degree of myocardial ischemia downstream from a given coronary stenosis: however, also plaque composition may play a crucial role in triggering future events especially in patients affected by acute coronary syndrome. Differences in plaque composition between FFR-positive and FFR negative lesions have never been assessed. Intracoronary Near-InfraRed Spectroscopy (NIRS) identifies lipid rich plaques that can potentially cause acute events. The aim of this study is to compare the lipid content expressed by LCBI (Lipid Core Burden Index) between functionally significant (FFR < 0.80) and non-significant (FFR > 0.80) stenoses in patients undergoing coronary angiography because of stable CAD and non-ST elevation acute coronary syndromes. This is an observational, prospective, multicentric study where we plan to collect 150 coronary lesions.

There is currently no prognostic or predictive risk marker for this urethral stricture disease. The most conservative standard treatment for urethral stricture (internal urethrotomy) has a very high recurrence rate (greater than 75%) and, on many occasions, reconstructive urologists have to choose within a great variety of further complex interventions. Knowing risk and predictive markers of this disease could help to optimize both the need and the approach for these surgeries and may offer a more individualized management to patients.