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Renal transplantation has grown rapidly over the past 30 years, resulting in an inadequate supply of organs to meet the ever-increasing demand. This has led to an increase in the number of living-related donors. Advances in imaging technology now allow safe, rapid, and relatively noninvasive evaluation of potential donors. Helical computed tomographic (CT) angiography is a fast, minimally invasive procedure that is quickly becoming the imaging modality of choice for preoperative evaluation of potential renal transplant donors. Helical CT, combined with low-osmolar intravenous contrast materials, has enabled CT angiography to depict arterial and venous anatomy accurately. Between July 1995 and March 1997, CT angiography was performed in 205 potential renal donors. Correlation with surgical findings in 136 donor nephrectomies helped confirm a high level of accuracy for CT angiography in the assessment of the renal vasculature: Sensitivity and specificity for identifying specific vessels was 99.6% and 99.6% for main renal arteries, 76.9% and 89.9% for polar arteries, and 98.7% and 95.5% for main renal veins, respectively. CT angiography allows the radiologist to provide the transplant surgeon with precise preoperative anatomy of the renal vasculature, thus reducing the risks and complications associated with the harvesting procedure and improving the chances for a successful outcome. However, accurate radiologic interpretation depends on the radiologist's experience level, attention to detail, and commitment to careful image evaluation.

Artifacts in spectral and color Doppler imaging can be confusing and lead to misinterpretation of flow information. The authors review these artifacts by considering three main causes: inappropriate equipment settings, anatomic factors, and physical and technical limitations of the modality. Incorrect gain, wall-filter, or velocity scale settings can cause loss of clinically important information or distortion of the tracing. Reflection of the Doppler signal from highly reflective surfaces can create a color Doppler mirror image. Vascular motion can introduce artifactual variation in velocity as the sample volume passes through different velocities in a laminar flow state. Unintentional motion can cause a generalized Doppler shift. Increasing the angle of Doppler interrogation degrades the quality of the tracing and gives the impression of spectral broadening. As angulation approaches 90 degrees, directional ambiguity can occur, suggesting bidirectional flow. Grating and side lobes can interrogate areas unrelated to the sample volume and introduce extraneous Doppler information to the apparent area of interrogation. Recognition of these artifacts is essential to proper interpretation of Doppler information and rendering a correct diagnosis.

Chemotherapy by direct hepatic arterial infusion (HAI) results in reduction in tumor mass in a large percentage of patients. The authors reviewed records for 45 patients with metastatic cancer of the gastrointestinal tract who underwent HAI chemotherapy with floxuridine, administrated via an implanted pump. Twenty-seven of the 45 patients suffered complications, including gastrointestinal ulceration (18%), hepatitis (24%), sclerosing cholangitis (7%), and abscess (2%). The complication rates in this series were similar to those previously reported. The toxicity of HAI chemotherapy continues to limit its efficacy.

Displacement of various landmarks within the pelvis by enlarging mass lesions can be used advantageously to determine the nature and origin of a particular mass. The noncompliant pelvic osseous ring accentuates the effect of displacement by forcing the vector inwards. This usually results in cephalad extension of a pelvic process into the abdomen. Lesions originating in the sidewall force the neurovascular bundle medially while central lesions will displace these structures against the noncompliant osseous pelvis. The differentiation of supralevator from infralevator lesions by CT aids in planning the appropriate approach to a lesion preoperatively. The various peritoneal spaces can become enlarged by intraperitoneal abscesses, fluid collections or tumor. These processes will also displace sidewall structures laterally against the osseous rim. It is extremely rare for an intraperitoneal process to extend below the level of the mid-femoral head. Extraperitoneal disease arising out of the pelvis may involve...