双超声

定义

一个双 超声波 is a test to see how blood moves through your arteries and veins.

选择的名字

Vascular 超声波; Peripheral vascular 超声波

如何执行测试

双工超声包括:

• Traditional 超声波: This uses sound waves that bounce off blood vessels to create pictures.
• Doppler 超声波: This records sound waves reflecting off moving objects, 比如血, to measure their speed and other aspects of how they flow.

There are different types of duplex 超声波 exams. 一些包括:

• Arterial and venous duplex 超声波 of the abdomen. This test examines blood vessels and blood flow in the abdominal area.
• 颈动脉双工超声 looks at the carotid artery in the neck.
• 双超声 of the extremities 看胳膊或腿.
• Renal duplex 超声波 examines the kidneys and their blood vessels.

You may need to wear a medical gown. 你躺在桌子上, and the 超声波 technician will spread a gel over the area being tested. The gel helps the sound waves get into your tissues.

A wand, called a transducer, is moved over the area being tested. This wand sends out the sound waves. A computer measures how the sound waves reflect back, and changes the sound waves into pictures. The Doppler creates a "swishing" sound, which is the sound of your blood moving through the arteries and veins.

You need to stay still during the exam. You may be asked to lie in different body positions, or to take a deep breath and hold it.

有时在一个 duplex 超声波 of the arteries of the legs, the health care provider may calculate an ankle-brachial index (ABI). You will need to wear blood pressure cuffs on your arms and legs for this test.

The ABI number is obtained by dividing the blood pressure in the ankle by the blood pressure in the arm. 值为0.9或更大为正常.

如何准备考试

Usually, there is no preparation for this test.

If you are having an 超声波 of your stomach area, you may be asked not to eat or drink after midnight. Tell the person doing the 超声波 exam if you are taking any medicines, 比如血 thinners. These might affect the results of the test.

考试的感觉如何

You may feel some pressure as the wand is moved over the body, but there is no discomfort most of the time.

为什么要进行测试

一个双 超声波 can show how blood flows to many parts of the body. It can also tell the width of a blood vessel and reveal any blockages. This test is a less invasive option than arteriography and 静脉造影术.

一个双 超声波 can help diagnose the following conditions:

• 腹主动脉瘤
• Arterial narrowing (stenosis) or blockage (occlusion)
• 血凝块
• 颈动脉闭塞性疾病(见: 颈动脉双)
• 肾血管性疾病
• 静脉曲张
• 静脉功能不全

A renal duplex 超声波 can also be used after transplant surgery. This shows how well a new kidney is working.

正常的结果

A normal result is normal blood flow through the veins and arteries. There is normal blood pressure and no sign of a narrowing or blockage of a blood vessel.

异常结果意味着什么

An abnormal result depends on the specific area being examined. An abnormal result may be due to a blood clot or plaque buildup in a blood vessel.

风险

没有风险.

注意事项

Smoking may change the results of an 超声波 of the arms and legs. This happens because nicotine can cause the arteries to shrink (constrict).

参考文献

Bonaca MP, Creager MA. 外周动脉疾病. In: Zipes DP, Libby P, Bonow RO, Mann DL, Tomaselli GF, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 11日艾德. Philadelphia, PA: Elsevier; 2019:chap 64.

Kremkau弗兰克-威廉姆斯. Principles and instruments of ultrasonography. 见:Pellerito JS, Polak JF，编. Introduction to Vascular Ultrasonography. 7日艾德. Philadelphia, PA: Elsevier; 2020:chap 2.

帕斯卡雷拉·L，马斯顿·W. 静脉疾病. In: Townsend CM Jr, Beauchamp RD, Evers BM, Mattox KL, eds. 萨比斯顿外科教科书. 21艾德. Philadelphia, PA: Elsevier; 2022:chap 65.

斯通助理，克拉克RM. Vascular laboratory: arterial duplex scanning. 见:Sidawy AN, Perler BA编. Rutherford's Vascular Surgery and Endovascular Therapy. 10日艾德. Philadelphia, PA: Elsevier; 2023:chap 22.