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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
Radiological diagnosis of ischemic lesions of the colon (author's transl) [Le diagnostic radiologique des altérations du gros intestin d'origine ischémique.]
No full text
Critical evaluation of renal masses' angiography
No full text152 consecutive space-occupying renal lesions (54 cancers, 66 single or multiple cysts, 18 pseudotumors, 8 inflammatory lesions, 3 hydronephroses, 3 hematomas) were studied by selective angiography, considering the signs noted in the three phases: arterial, nephrographic, and venous. The frequency of each of these angiographic signs in the different forms of renal pathology was evaluated. Based on this study, pathognomonic angiographic signs were identified for the various types of pathology. For each angiographic sign the 'diagnostic value' was calculated in order to differentiate malignant from benign space-occupying lesions. Dependent on the angiographic phase they are in, these signs constitute the arterial, nephrographic, and venous 'symptom constellation' characteristic of each lesion. The relationship between angiographic signs and either histologic type or size of tumor were analyzed. The causes of false positive and false negatives were investigated. The value of certain angiographic signs for a correct diagnosis of the cases judged as suspect or misinterpreted was discussed
MRI of liver metastases
No full textMR Imaging of liver metastases thanks to liver specific contrast media is able to identify small metastases, with higher sensitivity than computed tomograph
Angiographic diagnosis of endocrine tumors of the pancreas
No full textThe angiographic findings in 18 patients with endocrine tumors of the pancreas are analyzed. A literature review (262 cases) is performed in order to assess the accuracy of angiography in diagnosing islet cell tumors, in particular multiple and small (less than 1 cm) lesions. Problems of differential diagnosis of pancreatic and extrapancreatic structures and lesions are discussed
Accuracy of computed tomography in the screening of obstructive jaundice
No full textPercutaneous transhepatic cholangiography (PTC) has come back into greater use thanks to Chiba's needle. PTC, however, is useful only in obstructive jaundice (OJ). Since in OJ the dilatation of the intrahepatic biliary tract (IHBTD) is constant, the authors discussed CTs reliability in evaluating IHBTD in a series of 33 patients with OJ studied with PTC. The threshold of CT diagnosis of IHBTD was found to be equal to a doubled caliber of the normal biliary tract. This value is reached by 85% of the patients 2 weeks after the onset of OJ and in 98% between 2 and 3 weeks. CT is therefore usable as a screening method of PTC, as long as it is not performed before 2 weeks after the onset of OJ. After 2 weeks, if CT does not reveal IHBTD, it is possible to exclude OJ
[Angiographic signs of the small intestine (two cases) (author's transl)]
No full textThe authors describe 2 cases of ileal carcinoid. They evaluate the advantages of selective angiography over the traditional radiologic methods, considering their cases and the 39 found in the literature. The angiographic signs of the lesions localized to the bowel wall are rather scarse and non-specific. The signs of mesenteric infiltration, which is precocious and conspicuous in this type of tumour, are more significant. Liver metastases, which are very frequent, are hypervascularized. The angiographic pattern may be similar to that found in some inflammatory diseases, but can be differentiated from that of other neoplasms of the small intestine
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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