1,721,158 research outputs found
Whole-body magnetic resonance angiography with blood-pool agents
No full textAlthough often asymptomatic, peripheral arterial disease (PAD) is associated with significant morbidity in a large proportion of patients. Atherosclerosis is the underlying pathology in many instances, involving the whole arterial tree. Whole-body magnetic resonance angiography (MRA) permits rapid, non-invasive and accurate evaluation of the entire vascular system and can be used for both diagnostic purposes and monitoring of vascular involvement in diseases such as diabetes, Marfan's syndrome and Takayasu arteritis. MRA has been used successfully in the identification of high-grade stenosis in PAD, abnormalities of the ileocaval veins and carotid plaque imaging. Carotid disease is significantly correlated with severe coronary artery disease and renal artery atherosclerosis. Symptomatic lesions in one vascular bed are often related to additional asymptomatic atherosclerotic lesions in other vascular regions. MRA may be advantageous over computed tomographic angiography because it can be performed with contrast media virtually devoid of serious toxicity and without utilization of ionizing radiation. Display of the entire arterial vasculature can be achieved in <90 s, with excellent sensitivity and specificity. Recent technological advances, such as parallel imaging and the implementation of dedicated matrix coils, have further increased image quality, and in combination with the blood-pool contrast agents, such as gadofosveset trisodium (Vasovist, Bayer Schering Pharma AG, Berlin, Germany), extended imaging time, higher spatial resolution and larger anatomical coverage can be achieved
Cystic tumors of the pancreas
Full text linkCystic tumors of the pancreas are less frequent than solid lesions and are often detected incidentally, as many of these lesions are small and asymptomatic. However, they may be associated with pancreatitis or have malignant potential. With advancements in diagnostic imaging, cystic lesions of the pancreas are being detected with increasing frequency. Many lesions can cause a pancreatic cyst, most being non-neoplastic while approximately 10% are cystic tumors, ranging from benign to highly malignant tumors. With increasing experience it is becoming clear that the prevalence of pseudocyst among cystic lesions of the pancreas is lower than usually presumed. A presumptive diagnosis of pseudocyst based on imaging appearance alone can cause a diagnostic error, and neoplastic cysts of the pancreas are particularly susceptible to this misdiagnosis, which can result in inappropriate treatment. Cystic tumors of the pancreas are formed by serous or mucinous structures showing all stages of cellular differentiation. According to the WHO classification, they can be subdivided on the basis of their histological type and biological behavior into benign tumors, borderline tumors, and malignant tumors. Cystic pancreatic tumors can be subdivided into peripheral (serous cystadenomas, mucinous cystic tumors, solid and papillary epithelial neoplasms, cystic islet cell tumors), which do not communicate with the main pancreatic duct, and ductal tumors (mucinous tumor), according to their site of origin. On the basis of imaging criteria alone, it can be very difficult to differentiate non-tumoral cystic lesions from neoplastic ones. The management of these patients is complex, and it is important to correlate imaging findings with knowledge of the patient's symptoms and of the natural history and predictors of malignancy in pancreatic cysts
Gallbladder and bile duct functional imaging.
No full textThis is a comprehensive 2-volume reference that encompasses both GI and GU radiology. It provides advanced guidance to help you overcome the full range of diagnostic, therapeutic, and interventional challenges in abdominal imaging and combines an easy-to-use format with the greater depth that practitioners need.
The chapter on functional imaging of the gallbladder and bile duct focuses on non morphological informations, obtained with liver specific MR contrast agent
Ruolo della radiologia convenzionale nello studio del cuore e dei grandi vasi.
No full textVengono descritti gli aspetti radiologici alla radiografia del torace delle patologie cardiache e polmonari di origine cardiogen
Pituitary stalk thickening on MRI: when is the best time to re-scan and how long should we continue re-scanning for?
No full textContrast agents for hepatic MRI
Full text linkLiver specific contrast media (LSCM) can be subdivided according to different modalities of hepatic distribution: exclusive distribution to the hepatocellular compartment can be obtained using CM which accumulate within the hepatocytes after slow infusion; other CM demonstrate combined perfusion and hepatocyte-selective properties, with an initial distribution to the vascular-interstitial compartment (in an analogous manner to that of the conventional extracellular CM), thereafter, a fraction of the injected dose is taken up into the hepatocytes causing an increase in the signal intensity of the hepatic tissue. The use of the superparamagnetic effect of iron oxide particles is based on distribution in the reticuloendothelial system (RES), usually well represented in the normal parenchyma as well as in benign hepatocellular lesions, and absent in most malignant lesions. It is necessary to have an in-depth knowledge of either the biological and histological characteristics of focal liver lesions (FLL) or the enhancement mechanism of LSCM to gain significant accuracy in the differential diagnosis of FLL. Dynamic contrast-enhanced MRI is an important tool in the identification and characterization of FLL. With LSCM it is possible to differentiate benign from malignant lesions and hepatocellular lesions from non hepatocellular lesions with high accuracy. To understand the contrast behaviour after injection of LSCM it is necessary to correlate the contrast enhancement with both the biological and histological findings of FLL
Small liver lesions in oncologic patients: characterization with CT, MRI and contrast-enhanced US
Full text linkFocal liver lesions (FLLs) are frequently discovered during ultrasound examinations either in healthy subjects without a clinical history of cancer or during staging or follow-up procedures in oncologic patients or in routine surveillance of hepatopathic patients. In oncologic patients, the liver is the most common target of metastatic disease and accurate detection and characterisation of FLLs is prognostically fundamental during the initial staging as well as before and after pre-operative chemotherapy, as it can help to identify patients who are most likely to benefit from liver surgery. Moreover, early detection of primary or secondary liver malignancies increases the possibility of curative surgical resection or successful percutaneous ablation. As many FLLs in these patients are benign, a precise and preferably non-invasive method of differentiation from malignant metastatic nodules is needed. Moreover, the continuous follow-up of cancer patients requires an easily available, reliable and cost-effective diagnostic tool for the detection and characterization of FLLs
[Association of uveitis, alopecia and celiac disease]
No full textassociazione tra alopecia, celiachia ed uveite: case repor
Imaging CT of the spleen
No full textThe spleen is an intraperitoneal organ which is composed of a trabecular network of vessels, nerves and lymphatic tissue. Anatomical variants with regard to the shape and accessory spleens are seen. Systemic lymphatic diseases often result in splenomegaly. There are a number of different focal cystic or solid lesions, which can be found in the spleen in various pathological conditions. These are often inflammatory, but also neoplastic or developmental lesions are found. The following chapter will present the most common focal and diffuse pathologies of the spleen with special emphasis on their CT appearance
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