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Ultrasonography of leg veins is a risk-free, non-invasive procedure that uses ultrasound technology to give information about the anatomy, physiology and pathology of both the superficial and the deep venous systems, (SVS) and (DVS). It is indicated mainly on the study of two pathologies: venous thrombosis and venous insufficiency. As with heart ultrasound (echocardiography) studies, venous ultrasonography requires an understanding of hemodynamics in order to give useful examination reports. In chronic venous insufficiency (CVI), sonographic examination is of most benefit; in confirming varicose disease, making an assessment of the hemodynamics, and charting the progression of the disease and its response to treatment. It has become the reference standard for examining the condition and hemodynamics of the lower limb veins. Particular veins of the (DVS) and the (SVS) are looked at. The great saphenous vein (GSV) is a superficial vein which connects with the small saphenous vein (SSV) to drain into the common femoral vein (CFV). Perforator veins drain superficial veins into the deep veins. Three anatomic compartments are described (as networks), (N1) containing the deep veins, (N2) containing the perforator veins, and (N3) containing the superficial veins, known as the saphenous compartment,. This compartmentalisation makes it easier for the examiner to systematize and map. The GSV can be located in the saphenous compartment where together with the Giacomini vein and the accessory saphenous vein (ASV) an image resembling an eye, known as the 'eye sign' can be seen. The ASV which is often responsible for varicose veins, can be located at the 'alignment sign', where it is seen to align with the femoral vessels. Together with the GSV and the CFV these three veins create an image called the 'Mickey Mouse' sign. The examination report will include details of the deep and the superficial vein systems, and their mapping. The mapping is drawn on paper and then drawn on the patient before surgery. 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. Rapid advances since then in electronics, has greatly improved ultrasound transmission tomography. == Indications == The purpose of this examination is focused mainly on the study of two pathologies; venous thrombosis and venous insufficiency. It allows the examiner to evaluate the gross anatomy of the superficial and deep venous networks as well as the blood flow direction, which is crucial in determining vein pathology. It has become the reference standard used in the assessment of the condition and hemodynamics of the veins of the lower limbs. The normal physiological blood flow is anterograde, flowing from the periphery towards the heart, so that the evidence of an opposite, retrograde flow might indicate a pathology. The presence of a reflux is likewise of note; a reflux when not isolated in a vein (as simply retrograde), means that the blood flow is bi-directional where once the flow had been only anterograde. The procedure should not be used without a medical indication, such as with a reason to expect that a person is at heightened risk of having deep vein thrombosis.〔, which cites *〕 This screening is not effective at diagnosing DVT in the absence of other indications that the patient may have this condition.〔 A common example of overuse of this procedure is the practice of performing ultrasonography routinely on patients without indication after knee replacement or hip replacement.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Lower limbs venous ultrasonography」の詳細全文を読む スポンサード リンク
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