[Animal experimentation in radiology. Objectives, organizational and ethical problems].

The contribution of biomedical sciences to the scientific breakthroughs in the last years has benefitted also by experiments on animals. As for diagnostic imaging, the use of new contrast media for angiography, CT and MRI makes it necessary, according to the law, to perform preliminary animal studies to test efficacy, pharmacokinetics and pharmacodynamics of the contrast agents. Experimental animal studies of clinically well-established contrast agents are also justified by the need to implement new imaging modalities.

[Angiography with magnetic resonance of the ++carotid arteries. Evaluation of clinical results obtained with low magnetic field equipment].

Magnetic Resonance Angiography (MRA) is the latest diagnostic technique for the noninvasive evaluation of cardiovascular conditions. This technique has proved to be especially useful in the study of carotid arteries. All the clinical studies reported to date have been obtained at high or medium field strength; our purpose is to assess the clinical value of MRA in the evaluation of carotid arteries at low field strength.

[Hypermedia software for teaching anatomy of the upper abdomen with computerized tomography and magnetic resonance].

The authors have developed a hypermedia program for creating a tutorial of CT and MR anatomy of the upper abdomen. The program was created on a Mcintosh computer, with the Supercard software: it is made up of a series of windows, each of them containing images, texts, schematic representations and sound. Moreover, each window contains buttons which are activated with the mouse and allow different kinds of function, all created by the authors to be displayed.

Role of magnetic resonance imaging (MRI) in detecting liver changes after gallstone extracorporeal shock wave lithotripsy (ESWL).

Recently published literature on biliary extracorporeal shock wave lithotripsy (ESWL) has shown that high-energy ESWL utilizing high kV is more effective than the low-energy ESWL and low kV used previously. Prior studies have not reported injury to the gallbladder or adjacent liver following ESWL. Our study evaluated 29 patients that were treated with high kV ESWL.

Pancreatic beta-cell tumors: MRI.

Ten consecutive patients with surgically proven beta-islet cell tumors, strongly suspected clinically because of positive laboratory findings, were studied by MRI at 0.5 T. Results were correlated with CT and angiography.

Magnetic resonance angiography: current clinical applications.

Magnetic Resonance Angiography (MRA) is the newest non-invasive procedure for the evaluation of the vascular system. The basis to obtain images of vessels from Magnetic Resonance (MR) data rely upon the specific signal alteration determined by flowing blood. By using special techniques only these signals are evidenced, with cancelling of the surrounding stationary tissues.

[Magnetic resonance imaging of the esophagus with lumen opacification using a specific contrast agent].

A new contrast agent has been developed for the opacification of the esophageal lumen in Magnetic Resonance (MR) Imaging. The contrast agent consists of an emulsion of low-density and high-viscosity barium paste employed for the CT study of the esophagus (E.Z.

Carotid arteries: evaluation with low-field-strength MR angiography.

Magnetic resonance (MR) angiography of neck vessels was performed with a 0.2-T permanent magnet by using a two-dimensional, time-of-flight technique. Thirty-one patients were included in the study.

Arteriography in diagnosing hepatocellular carcinoma.

The diagnostic role of arteriography in the evaluation of hepatocellular carcinoma is pointed out. In the identification of large lesions angiography achieves a sensitivity of 100%. However, when evaluating small lesions (under 5 or 3 cm in diameter), the sensitivity is reported to be 82-89%.

Identification of coronary artery by-pass grafts: reliability of MRI in clinical practice.

In order to test MRI ability to detect the number and the sites of coronary artery by-pass grafts (CABGs), 22 patients with CABGs were studied. The detection of a neo-vessel in even one of the examination slices was considered as positive for the study, disregarding the difference between its origin and course. With such a criterion, MRI total percentage of vascular bridges identification resulted in 76.

A rare cause of digestive hemorrhage: an aneurysm of the superior pancreaticoduodenal artery rupturing into the duodenal stump of a Billroth II partial gastrectomy.

We report herein a case of an iatrogenic superior pancreaticoduodenal arterial aneurysm which ruptured into the duodenal stump of a Billroth II partial gastrectomy. Superselective angiography was used for the diagnosis, and successful embolization performed nonoperatively. A review of the literature revealed both the etiology and site of rupture in this case to be extremely uncommon.

Postsurgical follow-up of aortic dissections by MRI.

Fifteen patients with surgical repair for dissecting aneurysm were examined by Magnetic Resonance Imaging (MRI), using a 0.5 T super-conductive unit. Follow-up studies were obtained at 1 to 18 months (mean 7.

[Digestive hemorrhage caused by rupture of an aneurysm of the superior pancreaticoduodenal artery].

Aneurysms of the pancreaticoduodenal artery are rare. Nonoperative management of an iatrogenic superior pancreaticoduodenal artery aneurysm which ruptured into the duodenal stump of a Billroth II partial gastrectomy, is described here. Based on a literature review, both aetiology and site of rupture of this observation are very uncommon.

Intraarterial portography with gadopentetate dimeglumine: improved liver-to-lesion contrast in MR imaging.

Magnetic resonance imaging during arterial portography (MRAP) was performed by the authors in a selected group of 12 patients with hepatic lesions. A low dose of gadopentetate dimeglumine (4 mL of a 0.5-mol/L solution, corresponding to a dose of 0.

[Optimization of the techniques for studying the upper abdomen with magnetic resonance. II. Changes in the intrinsic contrast].

Magnetic Resonance imaging of the upper abdomen was performed on more than 300 patients. The aim of the study was to determine the influence of spin-echo parameters on intrinsic image contrast. Different TR (ranging 260 to 2000 ms) and TE (ranging 20 to 120 ms) values were employed in two patients with a hepatic metastases and in a healthy volunteer with a hepatic cyst.

Evaluation of hematoma by MRI in follow-up of aorto-femoral bypass.

We selected a population of 20 patients with atherosclerotic disease, submitted to implantation of aorto-femoral bypass graft. These patients were studied by MRI with T1- and T2-weighted sequences (w.s.

[Mediastinal lymphatic staging of bronchial cancer. Respective value of x-ray computed tomography and magnetic resonance imaging. Radio-surgical comparison].

Fifty patients with bronchogenic carcinoma were prospectively studied by both CT and MR during 10 days preceding thoracotomy. Results of CT and MR were compared with the surgical and pathology findings. No statistically significant difference was found between the two imaging methods for the evaluation of node involvement (N2).