Purpose: To determine the most efficacious dose of gadodiamide for three-dimensional (3D) contrast-enhanced (CE) magnetic resonance angiography (MRA) of the renal arteries on a patient level based on the sensitivity in detecting the main hemodynamically relevant (> or =50% or occlusion) renal artery stenosis (RAS) using intra-arterial digital subtraction angiography (IA DSA) as the gold standard.
Materials And Methods: This prospective, randomized, double-blind, parallel-group, multicenter study included 273 patients referred to IA DSA for suspected RAS. Patients underwent 3D CE MRA after injection of 0.
Objective: In our multi center trial we compared the potentials of biphasic contrast-enhanced computed tomography (CT) and a novel tissue-specific magnetic resonance imaging (MRI) contrast agent gadoxetic acid disodium in liver lesion characterization.
Methods: A total of 176 patients with 252 liver lesions were analyzed. There were 104 malignant and 148 benign lesions.
Rheumatoid arthritis (RA) is a chronic systemic disease of unknown origin that predominantly involves synovial tissue. RA affects 0.5%-1.
View Article and Find Full Text PDFWhether stroke in a patient with migraine and patent foramen ovale (PFO) is due to PFO or migraine is difficult to decide. In a 33-year-old woman with migraine with aura, a visual field defect developed acutely. Neurological investigation revealed double vision when looking to the left and exaggerated patella tendon reflexes.
View Article and Find Full Text PDFLeuk Lymphoma
February 2005
Multifocal leukoencephalopathy and sensory-motor polyneuropathy have not been reported as side-effects of long-lasting interferon alpha therapy in a single patient. In a 77-year-old man interferon alpha2b and interferon alpha2a were administered subsequently but continuously since 1984 for hairy cell leukemia. Since early 2000, left-sided hemi-hypesthesia occurred and the patient developed gait disturbance, proximal weakness of the lower limbs, bilateral stocking-type sensory disturbances, and restless leg syndrome.
View Article and Find Full Text PDFSemin Thorac Cardiovasc Surg
August 2006
Cardiovascular magnetic resonance (CMR) is playing an increasing role in the noninvasive assessment of the cardiothoracic patient. It provides rapid, high-resolution anatomical coverage, and accurate functional cardiovascular assessment without the need for ionizing radiation. In this article, we discuss the fundamental principles of CMR and outline the established and newer indications for its use.
View Article and Find Full Text PDFThe temporomandibular joint (TMJ) is a common site of complaint. Clicking sounds and pain are indicators of a frequent condition called internal derangement, most often affecting females. As a general term, internal derangement describes a structural abnormality within an articulation.
View Article and Find Full Text PDFPurpose: Evaluation and statistical analysis of the influence of THI with pulse-inversion technology on image quality in abdominal ultrasound in comparison to conventional sonography.
Material And Methods: In 25 patients 398 ultrasound images of the abdomen were evaluated in a prospective, double blind study. 49% of the images were obtained with THI sonography, 51% with conventional sonography, respectively.
Purpose: To compare contrast material-enhanced harmonic power Doppler ultrasonography (CHI) with conventional contrast-enhanced power Doppler ultrasound (CPD) in depicting the vascularity of fibroadenomas.
Materials And Methods: Forty patients with fibroadenomas (aged 19-61 years) underwent conventional contrast-enhanced and harmonic power Doppler US. According to a standardized examination protocol, serial dynamic scans were obtained before and at 30, 90 and 150 seconds after injection of contrast agent.
The aim of this study was to depict and characterize inflammatory soft tissue proliferations caused by rheumatoid arthritis (RA) in the craniocervical region by unenhanced and contrast-enhanced CT. Computed tomography of the craniocervical region was performed in 35 patients in the axial plane before and after the i.v.
View Article and Find Full Text PDFAlthough the exact pathogenesis of central pontine myelinolysis (CPM) is unknown, correction of hyponatremia, thyreotropin releasing hormone, plasmapheresis, and corticosteroids seem to be effective. Assuming intravenous immunoglobulins (IVIG) to also be effective in CPM, 0.4 g/kg body weight/d immunoglobulins were applied to a 48-year-old patient who developed CPM with double vision, dysarthria, dysphagia, and left-sided hemiparesis 3 weeks after spontaneous normalization of hyponatremia.
View Article and Find Full Text PDFThe purpose of this study was to compare liver contrast-enhancing characteristics of two superparamagnetic reticuloendothelial system (RES)-directed agents with different particle sizes, polycrystalline iron oxide nanocompounds (PION) and carboxydextran-coated maghemite (DDM128N/389, later referred to as DDM128), in an experimental model of focal radiation-induced hepatitis. PION, for the small particle size (31 nm), and DDM128, for the large particle size (59 nm), RES-directed agents were compared for liver enhancement after radiation-induced liver injury. A single x-irradiation exposure varying from 10 to 60 Gy was delivered to one side of the liver.
View Article and Find Full Text PDFRationale And Objectives: The authors characterize the appearance of the Achilles tendon in patients with rheumatoid arthritis and differentiate this appearance from degenerative tendinopathy in patients with chronic pain of the heel using magnetic resonance (MR) imaging.
Methods: Thirty patients with rheumatoid arthritis and 28 patients with chronic pain of the heel underwent MR imaging of the ankle and foot. Three radiologists independently assessed the MR images with respect to size, shape, and intratendinal signal characteristics of the Achilles tendon.
Purpose: Considerable clinical interest has focused on the size of ischemic myocardium. Fast MR imaging in conjunction with MR contrast media has the potential to identify hypoperfused and infarcted myocardium. This study used MR perfusion imaging to detect and quantify reperfused ischemic myocardium during a brief coronary occlusion and reperfusion, and to characterize the spatial extent of ischemic and reperfused ischemic myocardium relative to the "true" size of the area at risk as defined in histochemical morphometry at post mortem.
View Article and Find Full Text PDFThe purpose of this study was to compare a new MR macromolecular contrast medium (MMCM), gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA)-24-cascade-polymer, to a well-studied prototype MMCM, for the potential of distinguishing tissues of varying endothelial permeability. Three tissue models of varying capillary permeability were studied in a total of 46 rats: normal myocardium (normal capillaries), subcutaneously implanted adenocarcinoma (mild capillary leak), and reperfused infarcted myocardium (high capillary leak). TI-weighted MRI was performed before and dynamically after injection of either albumin-(Gd-DTPA)30 or the cascade polymer (each .
View Article and Find Full Text PDFVascular injuries in lumbar disk surgery, although rare, are serious complications which may be overlooked due to a broad range of clinical manifestations. It is important that surgeons and radiologists be aware of these potentially fatal complications and develop an appropriate symptom-based diagnostic paradigm. We reviewed 8099 consecutive cases of lumbar disk surgery, performed over a 14-year period at a single institution, for postoperative vascular complications.
View Article and Find Full Text PDFRationale And Objectives: The authors describe the magnetic resonance (MR) imaging characteristics in patients with gestational trophoblastic disease (GTD) before and after therapy and to correlate these findings with human gonadotropin levels and the specific histology of GTD.
Methods: Thirteen women (mean age, 30.1 years) with elevated human chorionic gonadotropin (HCG) levels and histologically proven GTD underwent MR examinations of the pelvis.
Stunned myocardium has been detected in patients treated successfully with thrombolytic agents. The hypothesis of this study was that fast gradient echo (GRE) imaging could be used to characterize the regional functional and perfusion abnormalities that are indicative of myocardial stunning. This study was designed to monitor and correlate the extent of wall thickness and perfusion abnormalities as determined by fast (segmented k space) cine and contrast enhanced GRE imaging, respectively.
View Article and Find Full Text PDFWe compared the liver enhancement of two superparamagnetic agents, polycrystalline iron oxide nanoparticles (PION) and PION coated with asialofetuin (ASF), in an experimental model of focal radiation-induced hepatitis. PION, a reticuloendothelial system-directed agent, and PION-ASF, a hepatocellular-directed agent, were compared for time-dependent liver enhancement in an experimental model of radiation-induced liver injury. Using the reticuloendothelial system (RES)-directed PION, the normal, nonirradiated portion of the liver decreased in signal intensity (SI) with a mean negative enhancement of -66% +/- 4, whereas the irradiated portion (60 Gy, 3 days before imaging) of the liver decreased in SI by -24% +/- 2, significantly less (P <.
View Article and Find Full Text PDFPurpose: To assess the effect of x rays on tumor capillary permeability with macromolecular contrast medium (MMCM)-enhanced magnetic resonance (MR) imaging.
Materials And Methods: One of paired R3230 mammary adenocarcinomas implanted in the flanks of 48 Fischer rats was treated with a single 5- or 15-Gy dose of x rays. After 1 or 3 days, MR imaging in 30 rats was performed unenhanced and enhanced with albumin-(gadolinium diethylenetriaminepentaacetic acid)30 (0.
The purpose of this study was to determine the efficacy of ultrafast computed tomography (UF CT) in patients with parotid masses poorly defined by magnetic resonance imaging (MRI) and to evaluate the diagnostic potential of three-dimensional (3-D) UF CT sialography when compared with conventional CT sialograms. Thirteen patients with clinical suspicion of a parotid mass, in whom MRI was degraded by motion, underwent UF CT of the parotid region. Two radiologists independently assessed the CT and MR with respect to tumor localization, intraglandular tumor location, tumor margin characteristics, and infiltration of surrounding tissue.
View Article and Find Full Text PDFRationale And Objectives: We compared the peritumoral vascular definition in rats using either a paramagnetic extracellular or a macromolecular contrast medium in combination with high-resolution magnetic resonance (MR) imaging.
Methods: High-resolution, three-dimensional spoiled gradient-refocused acquisition in a steady state (SPGR) images were acquired from tumor-bearing Fischer-344 rats before, immediately after, and again 40 min after administration of gadopentetate dimeglumine (0.1 mmol Gd/kg; n = 10) and albumin-(Gd-DTPA)30 (0.
AJNR Am J Neuroradiol
October 1995
Purpose: To evaluate the diagnostic potential of three-dimensional image processing of ultrafast CT sialography in comparison with conventional CT sialography in patients with parotid masses.
Methods: In nine patients, CT sialography was done with three-dimensional image processing. The visibility of anatomic details and pathologic findings, derived from three-dimensional images, were graded numerically by three observers and compared with the findings obtained from conventional CT sialograms.