For a patient of known weight, one can calculate the iodine dose needed to provide a desired level of hepatic enhancement. Use of a contrast material with a concentration of 240 mg L/mL is not recommended for dynamic incremental hepatic CT, except in small patients (eg, those weighing less than 73 kg).

No abstract

In hyperechoic renal masses, the presence of shadowing, a hypoechoic rim, and intratumoral cysts are important findings that may help distinguish AML from RCC.

Color Doppler ultrasound was used to image the ureteral jets in 17 healthy subjects and 26 patients with ureteral calculi proved with intravenous urography. In patients with ureteral calculi, three patterns of ureteral jets were seen: no detectable urine flow from the symptomatic side (12 patients), low-level continuous flow from the symptomatic side (four patients), and periodic ureteral jets on the symptomatic side that were not significantly different from ureteral jets of healthy subjects (10 patients). Of the 12 patients with high-grade obstruction on urograms, 11 had ureteral jets significantly different from those of healthy subjects (either no detectable ureteral jets or continuous low-level jets on the symptomatic side). Only three of the 11 patients with low-grade obstruction or nonobstructing stones had ureteral jets that were different from those of healthy subjects. It is concluded that analysis of ureteral jets with color Doppler can enable detection and qualitative determination of the degree of ureteral obstruction in many patients with unilateral ureteral calculi.

Current patterns of imaging utilization lead to frequent serendipitous discovery of renal lesions. Today, the majority of solid renal masses that are ultimately proved to be renal cell carcinomas were incidental findings on imaging studies performed for non-urinary tract symptoms. While earlier discovery has led to treatment of smaller and earlier-stage malignancies, the percentage of benign lesions discovered has also increased. A strategy for characterization of solid masses in adults based on the lesion's growth pattern, the "ball" versus the "bean," is presented. Common and uncommon renal masses, in concert with clinical and other imaging clues, are reviewed within the context of a renal ball or bean.