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31.
Didier Mathieu Alain Rahmouni Norbert Vasile Nedal Jazaerli Christophe Duvoux Jeanne Tran Van Nhieu Elie Serge Zafrani 《Journal of magnetic resonance imaging : JMRI》1994,4(3):506-508
This case report illustrates atypical magnetic resonance (MR) imaging findings in a liver hemangioma mimicking a malignant lesion—lower signal intensity than cerebrospinal fluid on T2-weighted spin-echo images and lack of early enhancement on dynamic contrast material—enhanced gradient-echo images. Pathologic analysis demonstrated nearly total replacement of the vascular cavities by dense fibrous tissue. In this rare, sclerosed form, this lesion could not be defined as a hemangioma with MR imaging. 相似文献
32.
Laurie M. Lomasney John F. Madden Wagdy S. Rizk Lawrence W. Hedlund Salutorio Martinez Robert E. Coleman William J. Richardson H. Dirk Sostman 《Journal of magnetic resonance imaging : JMRI》1994,4(3):441-449
Magnetic resonance (MR) imaging may be a noninvasive method for assessing perfusion of vascularized bone grafts placed for treatment of avascular necrosis. One proximal femur of seven beagles was devascularized, with insertion of a vascularized fibular graft. MR imaging at 1 week (seven dogs) and 6 weeks (five dogs) after surgery included pre- and postcontrast spin-echo sequences, unenhanced twodimensional time-of-flight (TOF) vascular imaging, and dynamic gradient-echo imaging during infusion of gadolinium. Relative signal intensity values of selected regions obtained from the dynamic gradientecho images were plotted as percent enhancement versus time. In the operated hip, MR imaging did not show enhancement in six of seven femoral heads and greater trochanters at 1 week after surgery, with similar results after 6 weeks. MR imaging of fibular grafts 6 weeks after surgery showed an initial rapid increase in enhancement and a subsequent slower increase in five of five dogs, although no enhancement was seen in six of seven dogs at 1 week. These findings contrasted with a rapid initial increase in enhancement followed by slow decline in non-operated hips. Two-dimensional TOP imaging did not show the vascular pedicle of the graft in any dog. Findings of radionuclide bone scanning performed 1 week after surgery were consistent with devascularization of the operated femur and fibular graft. However, tetracycline distribution and histologic findings confirmed the viability of five of five grafts within the devascularized femurs 6 weeks after surgery. Thus, dynamic contrast-enhanced MR imaging at 6 weeks after surgery is valuable for assessing vascular bone graft perfusion, while similar imaging at 1 week may suggest otherwise. 相似文献
33.
34.
Hubert A. Shaffer Jr. M.D. Donald A. Eckard Eduard E. de Lange M. R. Ramakrishnan 《Abdominal imaging》1988,13(1):221-223
Hypersensitivity reactions occurring during barium studies of the gastrointestinal tract are rare. A case is presented with radiographically demonstrated angioedema in the stomach and small bowel accompanied by allergic rhinitis, which was apparently an allergic response to the barium sulfate suspension. The reaction was documented twice during separate challenges to the barium suspension performed several months apart. 相似文献
35.
Th. Büttner S. Schulz W. Kuhn A. Blumenschein H. Przuntek 《European journal of neurology》1994,1(2):153-157
Colour discrimination and visual contrast perception were investigated in 18 patients with Huntington's disease (HD) and in 18 age- and sex-matched healthy volunteers using the Farnsworth-Munsell 100 Hue test (FM) and stationary contrast targets. The mean total error score (MTES) and the partial scores for the “red-green” and the “blue-yellow” axes in the FM of the patients with HD were significantly elevated as compared to controls (MTES in HD: 113.0 ± 90.8; MTES in controls: 19.2 ± 8.8). The spatial contrast sensitivity in HD patients was normal. The colour perception dysfunction indicates that the visual system is affected in HD. The visual disorder may be related to an imbalance of certain neurotransmitters in the visual system of HD patients. Possible anatomical sites of the dysfunction responsible for colour discrimination abnormalities could be the retinal cone system and/or impaired parvocellular central visual pathways in HD. 相似文献
36.
37.
Eugene C. Lin 《Journal of Cardiovascular Computed Tomography》2007,1(3):162-165
A conceptual framework to approach the application of contrast media in computed tomography angiography (CTA) is discussed. With an adequate conceptual framework, the physician or technologist should be able to modify or create CTA protocols to address specific clinical and patient circumstances. The focus of this review is coronary CTA, but the basic principles are applicable to CTA in any arterial system. 相似文献
38.
Takahiro Narishige Kensuke Egashira M.D. Yutaka Akatsuka Teisuke Takahashi Akira Takeshita 《Cardiovascular and interventional radiology》1993,16(6):343-347
The effects of an intracoronary administration of iomeprol, a new nonionic tri-iodinated water-soluble contrast medium, on
coronary circulation were compared to those of iopamidol and those of nitroglycerin in 6 chronically instrumented conscious
dogs. A pair of 10 MHz piezoelectric crystals and an electromagnetic flow probe were placed on the left circumflex coronary
artery (LCCA) to measure the epicardial coronary diameter (CD) and coronary blood flow (CBF). Polyethylene tubing for drug
administration was inserted into the LCCA proximal to the sonomicrometers. Iomeprol at the dose of 1 ml and 3 ml/min for 1
min significantly increased CD by 0.6±0.1% and 1.4±0.3%, respectively and CBF by 44.5±9% and 70±10%, respectively. Iopamidol
at the same rates also significantly increased CD by 0.8±0.1% and 1.5±0.3% and CBF by 50±11% and 82±14%, respectively. There
was no statistically significant difference between iomeprol-and iopamidol-induced increases in CD and CBF. However, the duration
of the increase in CD was significantly shorter (p<0.05) after iomeprol than after iopamidol. Nitroglycerin (10 μg/kg) significantly increased CD by 4.5±1% and CBF by 105±10%.
The increases in CD and CBF in response to iopamidol and iomeprol were significantly smaller (p<0.01) than to nitroglycerin. We conclude that vasodilating effects of iomeprol and iopamidol on the large epicardial coronary
artery and coronary blood flow are comparable in conscious dogs and significantly lower than after nitroglycerin in the doses
used by us.
This study was supported by a grant from the EI-ZA1 Pharmaceutical Co., Tokyo, Japan. 相似文献
39.
David M. Warshauer Richard C. Semelka Susan M. Ascher 《Journal of magnetic resonance imaging : JMRI》1994,4(4):553-557
Small nodular lesions in the liver and spleen have been reported as an infrequent manifestation of sarcoidosis. Five patients with this appearance on either dynamic contrast material—enhanced computed tomographic (CT) or ultrasound scans underwent magnetic resonance (MR) imaging with and without dynamic gadolinium enhancement. The lesions were relatively uniform in size, ranging from 0.5 to 1.5 cm. On CT scans, they were hypoattenuating relative to surrounding parenchyma. On MR images, the lesions were hypointense relative to background parenchyma with all sequences. No substantial enhancement was observed in the lesions, although lesion conspicuity decreased over time on serial postcontrast images. Lesion conspicuity was greatest on either T2-weighted fat-suppressed (T2FS) images or early-phase dynamic contrast-enhanced images. Abdominal adenopathy was seen in three of the five patients and was hyperintense relative to liver on T2FS images in two and intermediate in intensity in one patient. 相似文献
40.
Daniel L. Rubin Karen L. Falk Malcolm J. Sperling Michael Ross Sanjay Saini Barry Rothman Frank Shellock Elias Zerhouni David Stark Eric K. Outwater Udo Schmiedl Louis C. Kirby Judith Chezmar Terry Coates Miles Chang Jeffery M. Silverman Neil Rofsky Keith Burnett Julie Engel Stuart W. Young 《Journal of magnetic resonance imaging : JMRI》1997,7(5):865-872
The purpose of this study was to assess the effectiveness and safety of Gadolite Oral Suspension as a gastrointestinal (GI) contrast agent for MRI in a phase II and two phase III multicenter clinical trials. Gadolite was administered to 306 patients with known or suspected abdominal and/or pelvic disease. MRI with T1- and T2-weighted sequences was performed before and after ingestion. Efficacy was evaluated by having two masked readers rate the certainty of their MR diagnosis (0 = uncertain, 1 = probable, 2 = definite) on randomly presented pre- and post-Gadolite Oral Suspension enhanced images. Principal investigators also evaluated the images and established the final diagnosis. Vital signs, clinical chemistries, and adverse events were documented. Blood and urine samples were analyzed for gadolinium content to determine whether Gadolite Oral Suspension was absorbed systemically. Certainty in MR diagnosis increased significantly (P < .001) for both blinded readers between pre- and post-Gadolite images (.49–1.18 for reader 1; .46–1.53 for reader 2). Sensitivity, specificity, and accuracy also increased for both masked readers. No gadolinium was detected in blood or urine samples. There were no serious adverse events and no apparent drug-related trends in mean vital signs or laboratory values. Gadolite is a highly effective, safe, and well tolerated contrast agent for clinical use with MRI. 相似文献