Biomedical subjects

R Mattrey

Publications and source records attributed to R Mattrey.

7 recordsLinked to original sources

PubMed2002

Morphometry and strain distribution of the C57BL/6 mouse aorta.

The goal of the present study was to obtain a systematic set of data along the length of the mouse aorta to study variations of morphometry (diameter, wall thickness, and curvature), strain, and stress of the mouse aorta. Five mice were imaged with a 13-MHz ultrasound probe to determine the in vivo diameter along the aorta. A cast was made of these aortas to validate the ultrasonic diameter measurements. The root mean squared and systematic errors for these measurements were 12.6% and 6.4% of the mean ultrasound diameter, respectively. The longitudinal variations of geometry, stress, and strain from the aortic valve to the common iliac bifurcation were documented. Our results show that the residual circumferential strain leads to a uniformity of transmural strain of the aorta in the loaded state along the entire length of the aorta. Furthermore, we validated the incompressibility condition along the length of the aorta. These data of normal mice will serve as a reference state for the study of disease in future knockout models.

Animals↗

PubMed2000

Safety and efficacy of mangafodipir trisodium (MnDPDP) injection for hepatic MRI in adults: results of the U.S. multicenter phase III clinical trials (safety).

The short-term safety of mangafodipir trisodium (MnDPDP) injection was studied in 546 adults with known or suspected focal liver lesions. An initial contrast-enhanced computed tomography examination was followed by unenhanced magnetic resonance imaging (MRI), injection of MnDPDP (5 micromol/kg), and enhanced MRI. Adverse events were reported for 23% of the patients; most were mild to moderate in intensity, did not require treatment, and were not drug related. The most commonly reported adverse events were nausea (7%) and headache (4%). The incidence of serious adverse events was low (nine events in six patients) and not drug related. Injection-associated discomfort was reported for 69% of the patients, and the most commonly reported discomforts included heat (49%) and flushing (33%). Changes in laboratory values and vital signs were generally transient, were not clinically significant, and did not require treatment. There were no clinically significant short-term risks from exposure to MnDPDP.

Abdominal Pain↗

PubMed2000

Efficacy and safety of mangafodipir trisodium (MnDPDP) injection for hepatic MRI in adults: results of the U.S. Multicenter phase III clinical trials. Efficacy of early imaging.

The efficacy of contrast-enhanced magnetic resonance imaging (MRI) for detecting and characterizing, or excluding, hepatic masses was assessed in 404 patients, following the intravenous administration of mangafodipir trisodium (MnDPDP) injection, a hepatic MRI contrast agent. An initial contrast-enhanced computed tomography (CT) examination was followed by unenhanced MRI, injection of MnDPDP (5 micromol/kg IV), and enhanced MRI at 15 minutes post injection. Agreement of the radiologic diagnoses with the patients' final diagnoses was higher for enhanced MRI and for the combined unenhanced and enhanced MRI evaluations than for unenhanced MRI alone or enhanced CT using the clinical diagnosis as the gold standard. Mangafodipir-enhanced MRI uniquely provided additional diagnostic information in 48% of the patients, and patient management was consequently altered in 6% of the patients. MnDPDP-enhanced MRI was comparable or superior to unenhanced MRI and enhanced CT for the detection, classification, and diagnosis of focal liver lesions in patients with known or suspected focal liver disease.

Adult↗

PubMed1994

Imaging in the diagnosis and assessment of prognosis in localized prostate cancer. Consensus Conference on Diagnosis and Prognostic Parameters in Localized Prostate Cancer. Stockholm, Sweden, May 12-13, 1993.

As part of a WHO consensus conference on diagnosis and prognostic parameters in localized prostate cancer, a working group of experts discussed the role of various modern imaging techniques. Special attention was focused on transrectal ultrasound (TRUS) in combination with biopsies, magnetic resonance imaging (MRI) using endorectal coil and recent advances in these techniques. Some experimental techniques, especially hormone receptor scintigraphy and positron emission tomography were also discussed and new results were presented. We concluded that MRI seems to be superior to other imaging techniques in the preoperative assessment of local tumor stage. TRUS defends its place in the diagnostic armament; it is easily combined with multiple biopsies, the results of which are important in the assessment of the biological aggressiveness of prostate cancer. The present development in the field of nuclear medicine may result in techniques for in vivo characterization of tumors and will most certainly have important implications for diagnosis of prostate cancer in the future.

Animals↗

PubMed1990

Physical and acoustical properties of perfluorooctylbromide, an ultrasound contrast agent.

Perfluorooctylbromide (PFOB: C8F17Br) has been shown to be an effective ultrasound contrast agent when incorporated in tissues. The authors have recently demonstrated that PFOB also enhances tissues and Doppler signals during its capillary phase. To help elucidate the physical basis of their observations, the authors compared physical and acoustical properties of standard PFOB-lecithin emulsion with identical lecithin emulsion minus PFOB (vehicle) for concentrations of PFOB from 0% to 50% weight per volume. Propagation velocity, attenuation, and elastic modulus were measured using a 5-MHz source, 0.6-mm hydrophone, and a waveform digitizer, whereas viscosity, density, and particle size were measured directly. Vehicle showed no significant change with increasing concentration in any of the parameters measured. Perfluoroctylbromide exhibited significant linear increase in viscosity and mass density. Increasing concentrations of PFOB emulsion produced a dramatic linear decrease in velocity (r = .99) and a linear increase in attenuation coefficient, (r = .99). Derived values for bulk modulus (reciprocal of compressibility) also showed significant linear decrease (r = .98) with concentration of PFOB. For typical human in vivo blood concentrations of 3.5% PFOB emulsion, the following values were obtained: density, 1.02 g/mL; viscosity, 10.25 cP; velocity, 1450 m/second; attenuation, 2.8 dB/cm; and bulk modulus, 2.18 GPa. Significant differences were found between PFOB and vehicle at even low concentrations, although particle number and size distributions were the same for each, indicating that the presence of PFOB strongly influences acoustic properties. This enhancement was found to be linear over a wide range of concentrations, which supports the possibility of quantitative analysis.

Acoustics↗

PubMed1984

Experimental pericardial inflammation evaluated by computed tomography.

Experimental pericardial inflammation was evaluated with ungated and cardiac gated computed tomography (CT) in 12 dogs, including 2 controls. All were studied during and after contrast infusion; in addition, several were sequentially imaged for up to six weeks after inducing inflammation by instilling toxic materials into the pericardial space. All dogs with inflammation had contrast enhancement of the parietal and visceral pericardium; this could be demonstrated within one week of the pericardial insult and for up to six weeks and was frequently associated with effusion. Increased pericardial density was not seen in controls or animals with pericarditis prior to contrast infusion. This technique may be useful in evaluating acute pericardial inflammation.

Animals↗

PubMedDate not supplied

Pulmonary density distribution in experimental noncardiac canine pulmonary edema evaluated by computed transmission tomography.

We evaluated the density distribution (anterior-posterior) of the right lung in 19 acutely anesthetized supine dogs using computed transmission tomography (CTT). Eleven dogs served as controls, and eight received 0.12 cc/kg of intravenously administered oleic acid. The latter were sequentially imaged over 1 hour. Nine of these dogs (three control and six oleic acid dogs) had wet weight/dry weight ratios of the corresponding anterior and posterior lung sections evaluated immediately upon completion of the scans. In the control animals, the posterior (dependent) lung was 25 +/- 8% (+/- S.D.) denser than the anterior lung, and did not differ if a second section of the lung was evaluated (1 cm cranial or caudal), or if the animal was imaged on a second day (n = 6). In the oleic acid dogs, the posterior portion of the lung was significantly denser 10 minutes after injection of oleic acid (P less than 0.05), and almost twice as dense 1 hour after initial injection. The density changes determined by CTT in the anterior and posterior lung zones correlated well with the increasing regional wet weight/dry weight relationships determined from the lung on postmortem exam (r = 0.90). We conclude that early subtle density changes in the posterior lung can be found in oleic acid injury pulmonary edema. This can be easily quantitated using CTT, and may prove useful in following physiologic and therapeutic interventions during leaky membrane acute pulmonary injury.

Animals↗