Differences in MRI-measured contrast enhancement have been used for tissue characterization, particularly for the characterization of mammary tumours. T1 weighted spoiled gradient echo sequences have usually been acquired for this purpose and relative signal intensity increase (Srel) has been determined to quantify contrast uptake. The field strength dependence of this technique is evaluated in this paper by phantom measurements.
View Article and Find Full Text PDFA neonate with absent pulmonary valve syndrome was examined by means of echocardiography and magnetic resonance imaging (MRI). MRI provided an excellent evaluation of the intracardial morphology, vessel anatomy, mediastinal structures, and shunt flow; and it was superior to echocardiography for detection of aortopulmonary collaterals and vessel abnormalities. This case report of an uncommon cardiac abnormality confirms that MRI is a useful complementary modality to echocardiography in neonates and is recommended for problems with central pulmonary vessels and their relation to tracheobronchial structures.
View Article and Find Full Text PDFAJR Am J Roentgenol
November 1994
Objective: Selecting the appropriate surgical procedure for treatment of patients with osteosarcoma requires accurate preoperative evaluation of tumor extent. Establishing the presence or absence of joint involvement is particularly important. Accordingly, we studied the efficacy of MR imaging for detecting joint involvement in 46 patients with osteosarcoma around joint spaces.
View Article and Find Full Text PDFDisease status during follow-up evaluation of patients with carcinoma of the ovaries is the main criterion for the selection of appropriate management. A cohort analysis was performed to investigate if magnetic resonance imaging (MRI) could improve noninvasive assessment of disease status in patients with carcinoma of the ovaries during follow-up examination. Twenty-four women with carcinoma of the ovaries after primary surgical treatment with subsequent platinum containing chemotherapy were entered into the study.
View Article and Find Full Text PDFObjective: Although MR has been proven effective in evaluating many components of the musculoskeletal system, including ligaments, fibrocartilage, muscle, and bone marrow, its role in the evaluation of articular cartilage remains controversial. Recent studies have demonstrated that intraarticular injection of Gd-DTPA [MR arthrography (MRA)] improves the detection of cartilage abnormalities in cadaveric specimens. The aim of this study was to determine the efficacy of MRA for the detection of naturally occurring cartilage lesions in a clinical population.
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