Quantitative characterization of myocardial properties represent a rapidly emerging area of echocardiographic investigation. Because measurement of the ultrasonic integrated backscatter is theoretically applicable to analysis in vivo with reflected ultrasound, this study was performed to develop and evaluate a suitable method for measurement of quantitative backscatter in vivo. In view of the d...

Acoustic properties of two types of soft tissue-like media were measured as a function of compressive strain. Samples were subjected to uniaxial strains up to 40% along the axis of the transducer beam. Measurements were analyzed to test a common assumption made when using pulse-echo waveforms to track motion in soft tissues--that local properties of wave propagation and scattering are invariant...

Differences in reported backscatter factors, BSF, for low energy X-rays. A literature study.Differences in reported backscatter factors, nSF, for low energy X-rays. A literature study.

Two continuous-wave (CW) focused CO(2) Doppler lidars (9.1 and 10.6 µm) were developed for airborne in situ aerosol backscatter measurements. The complex path of reliably calibrating these systems, with different signal processors, for accurate derivation of atmospheric backscatter coefficients is documented. Lidar calibration for absolute backscatter measurement for both lidars is based on ran...

BACKGROUND Ultrasonic tissue characterization (UTC) can distinguish normal from infarcted myocardium. Infarcted myocardium shows an increase in integrated backscatter and loss of cardiac cycle-dependent variation in backscatter. The cyclic variation of backscatter is closely related to regional myocardial contractile function; the latter is a marker of myocardial ischemia. The present study was...

The use of acoustics to determine the pore properties of soils, such as porosity, permeability, and tortuosity, is well established. A theoretical surface impedance and complex bulk wavenumber was developed by K. Attenborough for porous media that incorporated the soil pore properties as parameters [J. Acoust. Soc. Am. 73, 785-799 (1983)]. Acoustic level difference measurements were used as a n...

This study was designed to determine whether a quantitative analysis of integrated backscatter amplitude distribution is potentially useful in characterizing the atherosclerotic lesion. One hundred measurements (10 X 10 array) were made in fresh aortic regions (2 cm X 2 cm) of nine normal and 19 atherosclerotic arterial walls. A 10 MHz transducer was used. The integrated backscatter distinguish...

AIMS To evaluate the effects of acute, atrial pacing-induced, reversible myocardial ischaemia on myocardial thickening and integrated backscatter cyclic variations in patients with or without coronary artery disease. METHODS AND RESULTS Thirty-six patients with suspected coronary artery disease underwent transoesophageal echocardiography with simultaneous atrial pacing, and coronary angiograp...

PURPOSE To compare central corneal backscatter obtained from Scheimpflug images between patients with insulin-dependent and non-insulin-dependent diabetes mellitus (IDDM and NIDDM, respectively) and healthy controls. METHODS Seven patients with IDDM (7 eyes), eleven patients with NIDDM (11 eyes), and sixteen healthy subjects (16 eyes) were included in this pilot study. Scheimpflug imaging sys...

In this study, we inter-compared observed Ku-, Xand C-band microwave backscatter from saline 14 cm, 8 cm, and 4 cm snow covers on smooth first-year sea ice. A Ku-, Xand C-band surface-borne polarimetric microwave scatterometer system was used to measure fully-polarimetric backscatter from the three snow covers, near-coincident with corresponding in situ snow thermophysical measurements. The stu...