Cardiovascular radiology最新文献

The technique and efficacy of therapeutic catheter embolization of the kidney with butyl-2-cyanoacrylate (Histoacryl) were studied in 80 rabbits (including control groups) and in 10 dogs. A mixture of butyl-2-cyanoacrylate, 50% glucose, and tantalum powder was used for the embolization. Complete and permanent vascular occlusion was found in nearly all cases. The main complication observed was a reflux of embolizing material into the lumbar arteries, which occurred in seven rabbits. Clinically therapeutic embolization was performed in six patients with hypernephroma. The indication for embolization in these patients, as well as in two others with iatrogenic lesions, was pronounced hematuria. Cessation of bleeding was achieved in all cases. For embolization the coaxial catheter technique is recommended; in special cases with extensive arteriovenous shunts, adjunctive balloon occlusion would be advisable.

Experimental perfusion of coronary arteries of guinea pig heart with contrast media causes various changes in electrolyte metabolism, depending on the chemical structures of the administered contrast media. These electrolyte changes are related to the tolerance of the myocardium to the contrast agents. Electron microscopic sections of human myocardium after coronary perfusion with Urografin-76 reveal that no alterations of subcellular structure occur.

Regional systolic left ventricular performance after myocardial infarct was assessed from 216 radionuclide angiograms performed in 170 patients. Recording of first transit of an intravenously injected bolus of technetium-99m pertechnetate was made by a multicrystal scintillation camera at a framing rate of 20 per second. The RAO view was used and a simultaneous ECG was employed. Statistics adequate for resolving regional events were obtained by a compact bolus input and phasic summation into one representative cycle of data obtained during left ventricular passage. Emphasis was given to imaging of regional systolic left ventricular function: perimeter images of end-systole and end-diastole, regional stroke volume images and ejection fraction images were processed. New trend images were presented that reflect total systolic contraction and improve image quality: regional rate of decrease and increase images, wall motion trend images and regional mean transit time images. In 96% of the cases, correspondence was found between the electrocardiographic location of the infarct and the region of major wall motion and ejection disorder. Akinesia and/or dyskinesia were seen in 77% of the cases; a ventricular aneurysm was found in 11%. Additional areas of wall motion anomalies were shown by 70%. Image analysis, nuclear image signs and their diagnostic meaning, as well as the indications for this nontraumatic examination in coronary heart disease are discussed. Relevant information for medical or surgical therapy can be obtained from early and follow-up studies in patients with unstable, progressive angina, ischemic electrocardiographic signs and those who have had myocardial infarctions.

This is a report of our experiences with the automatic contrast medium injector at selective coronary angiography during 836 examinations, and the quantitative evaluation of 193 single injections. Using average injection volumes per single injection of 5.0 ml for the left and 2.5 ml for the right coronary artery, a clear reduction of the quantity of contrast medium at constant definition can be registered. The variability in increase in the injection flow from 0 up to the peakflow appears to be important according to the anatomic and pathologic facts. Frequently a contrast medium reflux occurs out of the coronary ostium into the aorta. On the whole, automatic injection at selective coronary angiography is a reproducible and extensible method with few risks.

The precise diagnosis of carcinoma of the kidney is of particular importance because renal mass lesions are frequently encountered which require nephrectomy if malignant, and renal tissue conservation if benign. The diagnostic problems include those of differentiating benign from malignant tumors and tumors from cysts. Delineation of the extent of tumors is also essential for treatment planning and prognostic implications. Although the sequence of diagnostic imaging procedures utilized in suspected renal mass lesions varies somewhat depending on the clinical presentation, the following techniques are frequently employed until the relevant questions have been answered: urography, ultrasound and/or computed tomography, cyst puncture and contrast injection, angiography, and renal venography. These non-operative methods usually clarify the nature and extent of renal mass lesions and therefore have a major effect on therapy. A logical, systematic approach to their application avoids duplication and achieves appropriate diagnosis most rapidly.

Right ventricular outflow obstructive lesions are among the most prevalent congenital cardiac anomalies with a frequency ranging from 6--10% when considered as isolated anomalies. As part of a more complicated developmental complex, their frequency is undoubtedly higher. The diagnosis can be suspected by the traditional clinical and hemodynamic findings, but a firm diagnosis can only be made by angiography. An exact diagnosis is most important since most of these lesions can be surgically corrected.

Colonic angiodysplasia is a vascular lesion of the colon that may become the source of low grade chronic or intermittently massive rectal bleeding. It is a lesion of the elderly, almost always found in the cecum and the ascending colon. Etiology and pathogenesis are unknown. The diagnosis can be made with angiography based on the demonstration of a vascular tuft and early opacification of draining veins. Right hemicolectomy is the mode of therapy. The lesions are minute, and in resected specimens they can be found only with special vessel injection techniques. Histologically, the lesions represent clusters of dilated vessels, mostly veins, in the mucosa and submucosa of the cecum and ascending colon.