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It is very useful in an emergency situation and is performed just by vein compression using transducer pressure. [9] Compression ultrasonography has both high sensitivity and specificity for detecting DVT in symptomatic patients. Results are not reliable when the patient is symptomless and must be checked carefully.
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.
A duplex ultrasound (doppler ultrasonography and b-mode) can detect venous obstruction or valvular incompetence as the cause, and is used for planning venous ablation procedures, but it is not necessary in suspected venous insufficiency where surgical intervention is not indicated. [10] [6]
Medical ultrasound includes diagnostic techniques (mainly imaging techniques) using ultrasound, as well as therapeutic applications of ultrasound. In diagnosis, it is used to create an image of internal body structures such as tendons, muscles, joints, blood vessels, and internal organs, to measure some characteristics (e.g., distances and velocities) or to generate an informative audible sound.
Duplex evaluation is usually done prior to any invasive testing or surgical procedure. [8] Ultrasound duplex scanning can provide additional information that may guide therapeutic decisions. The location and severity of arterial narrowings and occlusions can be identified.
On duplex ultrasound, demonstration of echogenic material within the portal vein, complete or partial absence of colour flow in the portal vein, presence of collateral vessels around the portal vein or gall bladder that bypass the portal vein. [9] Portal vein thrombosis grading after Yerdel et al
During carotid duplex evaluation, the 2D B-mode structural image is superimposed with the doppler flow data, which provides a more realistic anatomical assessment. [2] B-mode ultrasound is able to assess the structure of the carotid arteries and can identify areas of stenosis. B-mode is used identify stenotic lesions and to assess the ...
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. Local sepsis of the lower limbs is contraindicated for this procedure. Low osmolar contrast agent with concentration of 240 mg/ml is preferable in this study ...