Search results
Results From The WOW.Com Content Network
The use of ultrasonography in a medical application was first used in the late 1940s in the United States. This use was soon followed in other countries with further research and development being carried out. The first report on Doppler ultrasound as a diagnostic tool for vascular disease was published in 1967–1968.
Unlike arterial ultrasonography, venous ultrasonography is carried out with the probe in a transversal position, (perpendicular to the vein axis), displaying cross-sections of the veins. [4] All collateral veins are better detected this way, including perforator veins, but of most importance is the detection of venous thrombosis.
Absence of the portal system in a first trimester case associated with hygroma and aorto-umbilical fistula. (A): Transverse plane of the upper abdomen with color Doppler applied, showing umbilical cord insertion, stomach, the prominent hepatic artery and no afferent liver venous perfusion; (B): midsagittal plane reconstructed from a three-dimensional volume acquisition were the crown-rump ...
Chronic venous insufficiency (CVI) is a medical condition characterized by blood pooling in the veins, leading to increased pressure and strain on the vein walls. [1] The most common cause of CVI is superficial venous reflux, which often results in the formation of varicose veins, a treatable condition. [2]
Lower limb venography is indicated in deep vein thrombosis, oedema with unknown cause, and congenital abnormality of the venous system. Less frequently it is used to demonstrate the incompetent valves of perforating veins. Doppler ultrasound is preferable rather than venography to access the competence of the veins.
A Doppler ultrasound blood flow detector, commonly called Doppler wand or Doppler probe, and a sphygmomanometer (blood pressure cuff) are usually needed. The blood pressure cuff is inflated proximal to the artery in question. Measured by the Doppler wand, the inflation continues until the pulse in the artery ceases.
The (a) blood vessel wall inner lining, (b) atheromatous disease within the wall and (c) connective tissues covering the outer surface of the blood vessel are echogenic, i.e. they return echoes making them visible on the ultrasound display. By contrast, the blood itself and the healthy muscular tissue portion of the blood vessel wall is ...
A transthoracic echocardiogram (TTE) is the most common type of echocardiogram, which is a still or moving image of the internal parts of the heart using ultrasound.In this case, the probe (or ultrasonic transducer) is placed on the chest or abdomen of the subject to get various views of the heart.