RESUMEN
An ionic (diatrizoate) and a non ionic (iopamidole) radiocontrast medium were compared as to their nephrotoxicity in a cohort of 21 patients with renal disease, 18 of which with normal renal function. The elevation of the urinary excretion of enzymes from renal tubular cells has been considered as a good index for renal tubular damage. We measured two lysosomal enzymes (NAG and beta glucuronidase) and a brush-border enzyme (gamma GT). In all patients we demonstrated an elevation of urinary excretion of the three enzymes already 12 hours after contrast medium administration. However, the elevation was statistically significant only after employment of the ionic contrast medium and concerned gamma GT and beta-glucuronidase; the urinary excretion of NAG did not vary significantly. Urinary enzymes levels returned to basal values 36 hours after intravenous pyelography. In conclusion, iopamidole showed a lower nephrotoxicity with respect to diatrizoate, as demonstrated by the lower levels of urinary enzymes excretion reached after its use.
Asunto(s)
Medios de Contraste/toxicidad , Riñón/enzimología , Acetilglucosaminidasa/orina , Glucuronidasa/orina , Humanos , Riñón/efectos de los fármacos , Urografía , gamma-Glutamiltransferasa/orinaRESUMEN
The Authors report their experience in the study of pulmonary embolism by xerotomography. The use of tomography for the study of pulmonary vascularization is well known, but this method is by far less frequently used than pulmonary angiography and pulmonary perfusion and ventilation scintigraphy. The enhancement of contrasts and contours and the ample area of exposure are the features which render the images obtained by xerotomography similar to those achieved by pulmonary angiography. Our experience up to the present time allows us to state that xerotomography may represent a valid diagnostic means in cases of acute pulmonary embolism, when scintigraphy is not feasible or following scintigraphy, when doubts regarding the clinical diagnosis still remain.
Asunto(s)
Embolia Pulmonar/diagnóstico por imagen , Enfermedad Aguda , Anciano , Femenino , Humanos , Masculino , Cintigrafía , XerorradiografíaRESUMEN
The purpose of this study was to establish the value of xeroradiographic patterns and their applicability in the automatic diagnosis of breast diseases. Such an evaluation is based on the comparison with the histologic examination, irrespective of the overall diagnostic judgement previously formulated. From an analysis of the material examined it was possible to ascertain the distribution frequency, the sensitivity, the specificity, the discriminating capacity, and finally the weight of each radiologic sign considered. There are xeroradiographic signs that are apparent almost exclusively in the malignant pathology and therefore can be considered as positive indices of the malignancy of the alteration. The specificity of the radiologic signs considered is very high, whereas the same cannot be said for the sensitivity. Moreover, a linear discriminating analysis made it possible to identify those semiologic elements which, with a minor probability of error, would attribute the pathologic process to the class verified histologically, for malignant neoplasms as well as benign tumors and dysplastic processes.
Asunto(s)
Mamografía , Xeromamografía , Enfermedades de la Mama/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , HumanosRESUMEN
The analytical study of the case material has allowed a precise evaluation of the distribution by age groups of the different pathologic processes of the breast, of the localization and dimensions of malignant tumors, as well as the diagnostic accuracy for those cases histologically ascertained and those with a follow-up. The diagnostic accuracy and the consequent reliability of the xeroradiographic method for the diagnosis of breast cancer is distinctly superior to that reported in the literature for traditional mammography, whereas for the differential diagnosis between circumscribed dysplastic manifestations and benign tumors xeromammography is not sufficiently reliable. The authors critically discuss the results and in particular the problem of false positives, which also include diagnostic errors that cannot be avoided in that they directly derive from the pathologic morphology of the disease process (plasma cell mastitis and sclerosing adenosis). As regards the problem of false negatives, they can be reduced within certain limits by resorting to other instrumental investigations. However, there are cases (1% of the malignant neoplasias histologically ascertained) that present a completely negative xeroradiographic finding. There are the limits of the radiologic investigation which cannot in any way be surmounted.