Biomedical subjects

W E Moritz

Publications and source records attributed to W E Moritz.

9 recordsLinked to original sources

PubMed1992

Prevalence of spindle cell sarcomas among wild Canada geese from southern Illinois.

Over a 6-yr period, two cases of neoplastic disease were diagnosed among 1,272 wild Canada geese (Branta canadensis interior) collected in Illinois (USA), Wisconsin (USA), and Ontario, Canada. One juvenile goose of each sex was involved. In both cases > 35 discrete masses were observed subdermally, intramuscularly, and within the body cavity. The tumors, diagnosed as spindle cell sarcomas, are among the most commonly observed neoplasms in free-living North American waterfowl. Based on our data, we suggest that these neoplasms occur with extremely low prevalence (0.002%) in free-living Canada geese.

Animals↗

PubMed1990

A triangulation method for the quantitative measurement of arterial blood velocity magnitude and direction in humans.

A triangulation method has been applied to a duplex ultrasound scanner to quantify blood flow velocities in two dimensions. A position locating system (PLS) connected to the scanhead locates the sample volume (SV) in 3-D space to a precision of 1 mm. The PLS is used to obtain flow velocity data from two independent lines of sight in the human femoral artery. Data are gathered from anatomic sites of interest along one line of sight. Later the computer directs the SV to interrogate the same points in space from a second line of sight. Water tank studies using both constant velocity and pulsatile string targets were used to validate the method. Velocity magnitudes could be calculated to within 5% error for Doppler angles below 75 degrees for various string depths and speeds; the error in Doppler angle calculation was usually less than 3 degrees. Results from the superficial femoral artery show flow velocity vectors are nearly parallel to the vessel walls. Peak systolic velocity magnitudes range from 63-66 cm/s in three presumed normal individuals. Following the validation studies addressed in this paper, this triangulation approach is intended in future work to document the complex nonaxial character of blood flow that occurs normally at branch points and in regions of intraluminal disease.

Blood Flow Velocity↗

PubMed1990

Ventricular volume measurement from a multiplanar transesophageal ultrasonic imaging system: an in vitro study.

We have developed a system to assess the feasibility of using multiple transesophageal ultrasonic images to measure left-ventricular volume, an important variable in patient management. The system includes a special transesophageal probe with a micromanipulator for acquiring cardiac images in multiple planes with known interplanar spatial relationship and an off-line processing system to compute the volume. In vitro studies with the probe demonstrated that the distance between two targets in space can be identified within 2 mm (SD = 0.4 mm) for points in the imaging plane 3.4 mm (SD = 0.5 mm) for points not lying in the imaging plane. This gives an average accuracy of +/- 6.5% for distances greater than 4.5 cm. Comparison of ultrasonic measurements of the volume of water-filled balloons and excised hearts to the volume required to fill them, revealed a correlation coefficient of 0.992, a regression line having a slope of 1.0 and an ordinate intercept at 0.2 mL, and a standard error of the estimate of 8 mL.

Calibration↗

PubMed1986

A new three-dimensional echocardiographic method of right ventricular volume measurement: in vitro validation.

Right ventricular volume is difficult to measure accurately from one or two views because the complexity of right ventricular shape invalidates simplifying geometric assumptions. This article describes a new three-dimensional echocardiographic reconstruction method of right ventricular volume calculation, and reports the results of testing this method in vitro using normal animal hearts and pathologic specimens from infants and children who died with aortic stenosis or hypoplastic left heart. The correlation with reference volumes was excellent for both groups (r = 0.98, n = 25 for the animal data; r = 0.97, n = 15 for the human data). Given the calculated echocardiographic volume (Vc), the reference volume (Vr) was best estimated by the equation Vr = 1.16 Vc for the animal data and Vr = 0.92 Vc for the human data. Three-dimensional echocardiographic measurement of right ventricular volume is an accurate method that deserves further study and application in a clinical setting.

Animals↗

PubMed1983