Search results for " Radiology"
showing 10 items of 442 documents
Gegenwärtiger Stellenwert der perkutanentranshepatischen Cholangiodrainage
2002
Percutaneous transhepatic biliary drainage (PTBD) is a well established method in the treatment of obstructive jaundice. Major indications are malignant diseases. PTBD may be necessary preoperatively in cases with severe jaundice or cholangitis or as part of palliative treatment concepts. In the past, it has been proposed that a period of preoperative PTBD may improve the morbidity rates of surgery. Various studies could not prove this theory. The significance of preoperative PTBD has changed, as observed during a 15 years period in our own institution, the indications for preoperative PTBD have decreased by half. At present, the majority of treatments with PTBD are palliative (almost 70 % …
Image-Guided Mini-Invasive Treatments for Vascular and Oncologic Diseases: Embolization Therapy
2020
Transcatheter Embolization, also called Embolotherapy, is a mini-invasive, non-surgical therapeutic solution used in Interventional Radiology to close blood vessels deliberately. A wide range of embolic agents is available in clinical practice, including metal coils and liquid agents. More recent advances in biomaterials such as shape-memory foam and in-situ gelling solutions have led to the development of new pre-clinical embolic agents. This review offers a brief overview of current and emerging technologies in the field of endovascular embolization. The focus is on devices, materials and techniques.
[CT-angiography in carotid stenosis].
1997
Purpose: Prospective evaluation of the accuracy of CT angiography (CTA) with different postprocessing for extracranial carotid artery in comparison with DSA. Method: one hundred patients were studied with standarized CTA. For postprocessing, MPR, MIP, and 3D reconstruction based on segmentation with upper and lower threshold were used. Intravascular density profiles were considered. All CTA studies were correlated with intra-arterial angiography. The degree and classification of stenoses was determined using the guidelines established by the NASCET collaborators. Results: Measurement of stenosis was possible by MPR in 82.5 %, by MIP in 85 %, and 3D in 100 %. Correct classification was found…
Coronary plaque imaging with multislice computed tomography: technique and clinical applications.
2006
The composition of an atherosclerotic lesion, rather than solely the degree of stenosis, is considered to be an important determinant of acute coronary events. Whereas until recently only invasive techniques have been able to provide clues about plaque composition with consistent reproducibility, several recent studies have revealed the potential of multislice computed tomography (MSCT) for noninvasive plaque imaging. Coronary MSCT has the potential to detect coronary plaques and to characterize their composition based on the X-ray attenuating features of each structure. MSCT may also reveal the total plaque burden (calcified and noncalcified components) for individual patients with coronar…
Interdisciplinary management of peripheral arteriovenous malformations: review of the literature and current proceedings.
2021
Arteriovenous malformations (AVMs) are a rare congenital vascular disorder. They represent a fast-flow vascular malformation. Clinically, AVMs present a heterogenous expression and can affect every part of the body. Here, we will solely focus on extracranial AVMs. Generally, AVMs progress with the patient's age. Patients often suffer from pulsation, skin discoloration, pain, ulceration, bleeding, and disfigurement. Diagnostic tools include color-coded duplex sonography, MRI and CT imaging, as well as the clinical examination. 4D dynamic perfusion-computed tomography may help in the interventional planning. Digital subtraction angiography is required during interventional therapy. AVMs pose …
Source strength determination in iridium-192 and cobalt-60 brachytherapy : A European survey on the level of agreement between clinical measurements …
2021
Background and purpose: Brachytherapy treatment outcomes depend on the accuracy of the delivered dose distribution, which is proportional to the reference air-kerma rate (RAKR). Current societal recommendations require the medical physicist to compare the measured RAKR values to the manufacturer source calibration certificate. The purpose of this work was to report agreement observed in current clinical practice in the European Union. Materials and methods: A European survey was performed for high- and pulsed-dose-rate (HDR and PDR) highenergy sources (Ir-192 and Co-60), to quantify observed RAKR differences. Medical physicists at eighteen hospitals from eight European countries were contac…
Imaging of VSOP labeled stem cells in agarose phantoms with susceptibility weighted and T2* weighted MR Imaging at 3T: determination of the detection…
2013
Objectives This study aimed to evaluate the detectability of stem cells labeled with very small iron oxide particles (VSOP) at 3T with susceptibility weighted (SWI) and T2* weighted imaging as a methodological basis for subsequent examinations in a large animal stroke model (sheep). Materials and Methods We examined ovine mesenchymal stem cells labeled with VSOP in agarose layer phantoms. The experiments were performed in 2 different groups, with quantities of 0–100,000 labeled cells per layer. 15 different SWI- and T2*-weighted sequences and 3 RF coils were used. All measurements were carried out on a clinical 3T MRI. Images of Group A were analyzed by four radiologists blinded for the num…
Risk-Reducing Gynecological Surgery in Lynch Syndrome: Results of an International Survey from the Prospective Lynch Syndrome Database.
2020
Purpose: To survey risk-reducing hysterectomy and bilateral salpingo-oophorectomy (BSO) practice and advice regarding hormone replacement therapy (HRT) in women with Lynch syndrome. Methods: We conducted a survey in 31 contributing centers from the Prospective Lynch Syndrome Database (PLSD), which incorporates 18 countries worldwide. The survey covered local policies for risk-reducing hysterectomy and BSO in Lynch syndrome, the timing when these measures are offered, the involvement of stakeholders and advice regarding HRT. Results: Risk-reducing hysterectomy and BSO are offered to path_MLH1 and path_MSH2 carriers in 20/21 (95%) contributing centers, to path_MSH6 carriers in 19/21 (91%) and…
Chronic Mesenteric Ischemia: Critical review and guidelines for management
2011
Background CMI is caused by chronic occlusive disease of mesenteric arteries. In such an uncommon disease, clear recommendations are strongly needed. Unfortunately, treatment options for symptomatic CMI are still controversial and no guidelines exist. Methods A systematic literature review of the last 25-years was conducted through MEDLINE, Embase, and Cochrane Review/Trials register to identify studies reporting on CMI treatment with more than 10 patients. Primary outcomes were perioperative mortality and morbidity rates. Secondary outcomes were survival rates, primary and secondary patency rates, vessels treated, CMI recurrence, follow-up (FU), technical success (TS), and in-hospital leng…
RADIOPROTECTION IN 2018: AN UPDATE
2018
Fluoroscopically-guided interventional procedures are performed in large numbers in Europe and in the United States. Radiation doses received by interventional radiologists can vary for the same type of procedure and for similar patient doses. Occupational radiation protection is a necessity whenever radiation is used in the practice of medicine. The International Commission on Radiological Protection is engaging against occupational radiation damages, publishing regular recommendations on dose limits. These limits are expressed as effective doses for the whole body and also as equivalent doses for particular regions or tissues of practitioners’ bodies. Shielding and personal protective clo…