Discrete form sensitivity functions are derived for a number of measurement types employed in autocorrelation-based ultrasound-modulated optical tomography. The Jacobian for a particular problem is constructed from the set of such sensitivity functions arising from a raster scan of a focused ultrasound field through a turbid medium. A linear reconstruction of an absorption perturbation is perfo...

Ovarian cancer is the leading cause of death from gynaecological malignancies. No precancerous lesions have been identified. Bimanual examination has not been proven to be of value as a screening test. Transvaginal ultrasound examination, with or without measurement of CA 125 levels, is currently being evaluated for population screening. Women at high risk of ovarian cancer should be screened a...

In ultrasound, a high frequency sound wave is launched into the eye with the help of a probe and the sound wave is reflected from different boundaries between microstructures. However, the OCT uses light rather than ultrasound. The speed of the light is almost a million times faster than sound and this difference allows the measurement of structures with resolution of =10 μ compared to 100μ sca...

The cardiovascular system has become the most important subject of clinical research, particularly measurement of arterial blood flow. Therefore correct determination of arterial diameter is crucial. We propose a novel, semi-automatic method for artery lumen detection. The method is based on Gaussian probability function. Usability of our proposed method was assessed by analyzing ultrasound B-m...

Versatile system for ultrasound equipment parameters measurement is presented. The system is based on single direct digital synthesis (DDS) generator which is used for excitation and dual simultaneous sampling analog-to-digit (ADC) conversion channels. System is dedicated for ultrasound equipment frequency domain parameters measurement: transduction AC response, insertion loss AC response, harm...

OBJECTIVE To evaluate left ventricular enlargement in the lateral projection of the chest using the Hoffman and Rigler sign. BACKGROUND The Hoffman and Rigler sign for determining left ventricular enlargement was suggested as early as 1965 before the routine use of echocardiography. METHODS We studied 136 patients who had had cardiac ultrasound and chest X-rays with lateral projections. We ...

introduction: arterial stiffness is an important predictor of cardiovascular risk. several indices have been  introduced to estimate the arterial stiffness based on the changes in the brachial blood pressure. since the  substitution  of  the  blood  pressure  changes  in  the  central  arteries  such  as  carotid  with  the  blood  pressure  changes in the brachial results in error in the blood...

Tomographic imaging techniques such as ultrasound can provide important information in the evaluation of vascular anatomy. Recent technical advances have permitted fabrication of a small (1.83 mm), phased-array, intravascular ultrasonic imaging catheter capable of continuous real-time, cross-sectional imaging of blood vessels. We used this imaging catheter to compare intraluminal ultrasound wit...

BACKGROUND To compare 2D transperineal ultrasound assessment of cervical dilatation with vaginal examination and to investigate intra-observer variability of the ultrasound method. METHODS A prospective observational study was performed at Skane University Hospital, Lund, Sweden between October 2013 and June 2014. Women with one fetus in cephalic presentation at term had the cervical dilatati...

Accurate assessment of the orifice area and/or the pressure gradient is an important factor for determining whether surgery is necessary or not. Transthoracic Echocardiography (TTE) is the method of choice to determine the severity of aortic valve stenosis. By using Doppler ultrasound, the maximum velocity over the valve is measured and used to calculate the peak pressure gradient. However, ult...