The adrenal gland is involved by a range of neoplasms, including primary and metastatic malignant tumors; however, the most common tumor detected is the incidental benign adenoma. Although computed tomographic (CT) findings will not always yield a definitive diagnosis, attention to these findings provides a road map to guide image interpretation. Adenomas typically demonstrate rapid washout, which is defined as an absolute percentage washout (APW) of more than 60% and a relative percentage washout (RPW) of more than 40% on delayed images. Adrenocortical carcinoma typically has an RPW of less than 40%; however, large size and heterogeneity are more reliable indicators of the diagnosis than are washout values. Washout characteristics of pheochromocytoma are variable; in conjunction with high levels of dynamic enhancement, pheochromocytomas may mimic adenoma (ie, APW > 60%, RPW > 40%). Myelolipomas appear as well-defined masses with variable quantities of fat and soft tissue. After contrast material administration, metastases usually demonstrate slower washout on delayed images (APW < 60%, RPW < 40%) than do adenomas, although hypervascular metastases may enhance similarly to pheochromocytoma. Finally, a number of nonadrenal pathologic conditions have been reported to mimic adrenal masses at CT.

OBJECTIVE. Aneurysms of the splenic artery are being diagnosed with greater frequency as incidental findings on cross-sectional imaging. Splenic artery pseudoaneurysms are even more rare than true aneurysms. This article reviews the clinical features and management of splenic artery aneurysms and pseudoaneurysms. A variety of cases are presented to show the range of CT appearances.CONCLUSION. Radiologists who identify either type of splenic artery lesion should recognize the clinical and pathophysiologic distinctions between these two forms of splenic vascular pathology and understand the differences in management.

OBJECTIVE. After traumatic splenic injury or splenectomy, small isolated spleens may develop. These implants are not limited to the left upper quadrant, and splenosis in other locations can mimic other pathologic entities. This pictorial essay presents the range of appearances of intraabdominal and pelvic splenosis. CONCLUSION. Radiologists can suggest or establish the correct diagnosis of splenosis in the appropriate clinical setting, particularly in less typical cases, to avert unnecessary tissue sampling.

OBJECTIVE. The two most widely used postprocessing 3D tools in clinical practice are volume rendering (VR) and maximum intensity projection (MIP). With the use of current-generation MDCT, these techniques enable accurate characterization of arterial anatomy and pathology in all anatomic regions. Recently, the VR algorithm has been enhanced by the incorporation of a new lighting model. This new technique—called cinematic rendering—generates photorealistic images with the potential to more accurately depict anatomic detail. CONCLUSION. As an enhancement of the technology championed in VR, cinematic rendering promises to provide additional anatomic detail for MDCT interpretation and display. Future investigations must be conducted to evaluate the diagnostic accuracy of cinematic rendering and determine whether interpretative pitfalls result from its unique lighting model in practice.

Computed tomography (CT) is an integral tool in the assessment of adrenal masses. Dedicated adrenal CT is performed for a range of indications, including hormonal abnormalities suggestive of a functional adrenal mass and adrenal cancer staging. It is important to have an understanding of the published data that guide protocol design and image interpretation. Whether an adrenal mass is identified serendipitously or is being imaged for further characterization, there are several CT findings that contribute to the diagnosis, such as lesion size, precontrast attenuation, level of enhancement at 60 seconds and on delayed images, percentage washout on delayed images, histogram analysis, and extent (involvement of the inferior vena cava and bilaterality). In the past decade, a body of pertinent literature has evolved, addressing each of these measures individually.