[Potentials of echography for diagnosing x-ray-negative calculi].

The objective of the authors, with the present paper, is to specify the possibilities of echography in patients with "negative" renal lithiasis. A total of 54 patients were studied, grouped in two subgroups: subgroup A--33 patients with native-graphy, urography and echography, subgroup B--21 patients with chronic renal insufficiency and intolerance to X-ray contrast media, to whom only native-graphy and echography were performed. The authors concluded, on the base of the statistical calculations, that echography in the patients studied by them, has a higher percentage probability of differentiating the negative concrements than urography.