US and CT evaluation of acute pelvic pain of gynecologic origin in nonpregnant premenopausal patients.

The interpretation of imaging findings in the premenopausal patient with acute pelvic pain is influenced by knowledge of the physiologic changes that occur in the pelvis as well as by the patient's clinical history. Although ultrasonography (US) is the modality of choice for initial imaging, gynecologic disease is detected or suspected with increasing frequency at computed tomography (CT) because of the increasing availability and use of this modality. As a result, the recognition of common features of gynecologic entities on both US and CT images is essential for prompt diagnosis and expeditious management. Categorizing lesions according to their anatomic location, physiologic or pathologic origin, and internal characteristics (cystic, solid, or mixed) allows efficient and accurate diagnosis.

Lines and stripes: where did they go?--From conventional radiography to CT.

Frontal and lateral radiography has traditionally been used to evaluate the chest, although computed tomography (CT) and high-resolution CT are increasingly being used as an adjunct to conventional radiography for the evaluation of parenchymal and mediastinal disease. Nevertheless, radiography remains a very important modality in this context, and use of chest radiography alone can provide a vast amount of useful information. This information is derived from the configurations and interrelationships of the anatomic structures in the lung, mediastinum, and pleura and forms the basis of the "lines and stripes" concept, which plays a valuable role in establishing a diagnosis before proceeding to CT. The inability to recognize that a chest radiograph is abnormal owing to displacement of one of these lines or stripes may lead to failure to request a potentially valuable CT examination. Radiologists must be familiar with the anatomic basis of these mediastinal lines and stripes and be able to recognize their normal and abnormal appearances. In this way, they can develop an appropriate differential diagnosis prior to obtaining additional information with chest CT.