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超声波检测时涂的胶有什么用 – 译学馆
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超声波检测时涂的胶有什么用

What Does Ultrasound Gel Do?

一生中您的身影可能会出现在上百张照片里 可能是在生日聚会上 毕业时 也有可能是
You might be in hundreds of photos in your life, at birthday parties, graduations, or
一张和朋友们的自拍
just snapping a selfie with friends.
但您的第一张照片可能是您仍在妈妈的腹中时拍下的
But the very first photo of you was probably taken while you were still inside your mom
这要归功于超声波的力量
– thanks to the power of ultrasound.
医生们借助超声波压电换能器产生超声波 超声波穿过
Doctors can use an ultrasound transducer to make ultrasound waves that travel through
您的身体 在各个柔软湿润的部位发生反射 比如各种脏器 或胎儿
your body, and reflect off different squishy bits, like organs, or a fetus.
然后 压电换能器通过反射回来的超声波生成图像
Then, the transducer uses the reflected waves to create an image.
那些涂到您身上的冷冰冰 黏糊糊的凝胶是为了帮助这些超声波成功抵达那些
That cold, sticky gel gets smeared on your body to help these waves make it to those
内部组织
inner tissues.
但它究竟是怎么做到的呢?
But how exactly does it work?
是这样的 超声波是声波的一种
Well, ultrasound waves are just another type of sound wave.
声波通过粒子的前后震动传播 就比如组成空气的粒子
And sound waves travel by vibrating particles back and forth, like the ones that make up air.
声音的频率越高 震动越快
The higher the frequency of a sound, the faster the vibrations.
在极高的频率下 大约20千赫兹震动就无法被
At really high frequencies – around 20 kiloHertz – the vibrations can’t be picked up by
人的耳朵感知 因此我们称之为超声波
human ears, so we call them ultrasound waves.
由于超声波就是声音 所以它用在医学成像上非常安全
Because ultrasound is just … sound, it’s really safe for medical imaging.
当声波从一种媒介进入另一种媒介时比如从空气中进入您的皮肤 或者是从皮肤
When sound waves travel from one medium to another, like from air to your skin, or skin
进入您的肝脏 声波能够被部分反射
to your liver, they can be partially reflected.
同时这些高频 短波超声波尤其擅长反射
And these high-frequency, short-wavelength ultrasound waves are especially good at reflecting
且不过分分散
without spreading out too much.
因此它们可用于精细成像 及回声定位 如果您是只
That’s why they’re good for making detailed images, and for echolocation if you’re a
蝙蝠或海豚的话
bat or dolphin.
那医生们是如何让这些声波进入您的身体反射出您的器官 而不仅仅只是
But how do doctors make sure the waves travel into your body to reflect off organs, instead
被您的皮肤反弹掉呢?
of just bouncing off your skin?
超声波凝胶在此就派上用场了
Here’s where ultrasound gel comes into play.
物体的音阻 总的来说 就是其对由声音引发的震动的耐受度
Something’s acoustic impedance – basically, how much it resists vibration due to sound
当声波在两种材料间传递时 物体的音阻会影响声波的反射程度
– affects how much a sound wave will reflect when it travels between two materials.
如果音阻变化过大 比如从空气进入人的皮肤 大部分声波
If there’s a huge change in acoustic impedance, like from air to human skin, sound waves will
就会被反弹
mostly bounce off.
但超声波凝胶由水和聚合物如甘油 丙二醇混合而成
But ultrasound gel is a mix of water and polymers like glycerin and propylene glycol, and has
其具有和人皮肤极其相似的音阻
an acoustic impedance that’s really similar to human skin.
通过压电换能器在凝胶中产生的超声波有着更高的
By using a transducer to make ultrasound waves in that gel, the waves have a much better
几率传导进入您的身体 且当场被反弹的超声波更少
chance of transferring into your body, with less reflection right off the bat.
随着超声波越传越深 部分超声波会在遇到不同组织类型时发生反射
As the waves travel deeper, some will reflect every time there’s a change in tissue type,
比如从子宫内膜传导到宝宝的小手指
like from the lining of a womb to tiny baby fingers.
压电换能器追踪反射回来的声波的传导时间
The transducer keeps track of things like how long the reflected waves were traveling,
频率和振幅
and the frequency and amplitude of the wave.
然后 电脑通过这些信息生成您身体内部的图像
Then, a computer uses all this information to generate images of what’s inside you.
多亏了这些您听不见的声音
All thanks to sounds that you can’t even hear.
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answers coming.
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视频概述

本视频从超声波成像原理出发,对超声波检查时所涂凝胶的作用进行说明

听录译者

收集自网络

翻译译者

蛤?

审核员

Ah~Qiu

视频来源

https://www.youtube.com/watch?v=SeqlHprotxU

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