Interactive multiplanar reformation of conventional two-dimensional MR images.

In this report, we describe a new application for three-dimensional computer image processing that can provide for improved depiction of anatomical structures on routine nonvolumetric magnetic resonance (MR) examinations. The technique can be applied to standard two-dimensional MR images of the brain, spine, musculoskeletal system, and body including those obtained with relatively thick slices and with an intersection gap. This report demonstrates use of the reformation technique to establish retrospectively the symmetry in bilateral structures that were displayed out of alignment due to suboptimal patient positioning or patient motion during image acquisition and to improve the depiction of anatomical structures that were oriented out of the plane of original image acquisition. This method can be performed interactively in near real time, requires no increase in patient examination time, and has potential application throughout the body.

Extension of vessels through hepatic neoplasms: MR and CT findings.

The undisturbed extension of vessels through an area of abnormal hepatic signal intensity on magnetic resonance (MR) images or abnormal attenuation on computed tomographic (CT) scans has been used as evidence of benign focal fatty infiltration and malignant hepatic neoplasms. Five cases are described in which either portal or hepatic veins extended through a hepatic lesion without evidence of appreciable mass effect, occlusion, or displacement of the vessels. These pathologically proved malignancies included hepatic lymphoma, metastatic melanoma, and metastatic adenocarcinoma.

Chemical shift misregistration artifact: increased conspicuity following intravenous administration of gadopentetate dimeglumine.

We have observed increased conspicuity of chemical shift misregistration artifact (CSMA) associated with enhancing structures on MR images after the intravenous administration of gadopentetate dimeglumine compared with corresponding unenhanced images. In this study, we investigate the influence of gadopentetate dimeglumine administration on the conspicuity of CSMA in MR imaging of the kidneys. Nine gadopentetate-enhanced and unenhanced T1-weighted images of the kidneys were evaluated in a side-by-side fashion for the conspicuity of both the high and low signal intensity (SI) components of CSMA. A phantom study of saline in a bath of oil and increasing concentrations of gadopentetate dimeglumine in a bath of oil was performed. There was increased conspicuity of both the high and low SI components of CSMA in gadopentetate-enhanced images compared with unenhanced images in all study cases and in the phantom samples containing gadopentetate compared with the saline control. In conclusion, the administration of gadopentetate dimeglumine results in increased conspicuity of CSMA on MR images of the kidneys.

A prototype of a high-resolution computerized radiology teaching file.

Computers provide an excellent tool for handling the task of organizing a radiology teaching file. Currently available computerized teaching files are either film-based, slide-based, or use laser-disc video technology for image display. There are obvious advantages to having the management of radiologic images under the control of a computer, and the need for a higher resolution alternative to video laser-disc technology becomes apparent when one tries to computerize a chest radiology teaching file. We describe the prototype of such a system, named MIRTLE, (the Mallinckrodt Institute of Radiology Teaching and Learning Environment) which was designed to integrate text under the control of a custom data base with high-resolution digital images from a Picture Archiving and Communications System. This system with its easy-to-use windows environment should allow a significant increase in the use of the radiology teaching file.