Ultrasound waves and the kidney

In summary, the ultrasound traveled through the kidney tissue at a faster speed than normal body tissue. The reflected signals were recorded at 20, 75, and 152 microseconds from the skin, front of the kidney, and back of the kidney, respectively. The calculated length of the kidney is 6 cm.
  • #1
Kolika28
146
28

Homework Statement


In a kidney study, ultrasound was used with frequency 3.5 MHz. In normal body tissue, the speed of the ultrasound is 1.50 km / s, while the speed in the kidney tissue is 1.55 km / s. Reflected signals came as follows: after 20 microseconds from the skin, after 75 microseconds from the front of the kidney, and after 152 microseconds from the back of the kidney.
Find out how long the kidney is across.

Homework Equations


S=v*t

The Attempt at a Solution


(152-75-20)/2=28,5
S=v*t=(1,55*1000)*(28,5*10^(-6)=0,044175

But the answer is 6 cm
 
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  • #2
Kolika28 said:

The Attempt at a Solution


(152-75-20)/2=28,5
S=v*t=(1,55*1000)*(28,5*10^(-6)=0,044175
Please elaborate your reasoning; can you explain in words what your calculation is trying to accomplish?

Have you made a sketch of the sound paths?
 
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  • #3
Kolika28 said:

Homework Statement


In a kidney study, ultrasound was used with frequency 3.5 MHz. In normal body tissue, the speed of the ultrasound is 1.50 km / s, while the speed in the kidney tissue is 1.55 km / s. Reflected signals came as follows: after 20 microseconds from the skin, after 75 microseconds from the front of the kidney, and after 152 microseconds from the back of the kidney.
Find out how long the kidney is across.

Homework Equations


S=v*t

The Attempt at a Solution


(152-75-20)/2=28,5
S=v*t=(1,55*1000)*(28,5*10^(-6)=0,044175

But the answer is 6 cm

Explain to yourself the path of the ultrasound, broken down into stages with the time for each.
 
  • #4
Ok, I can try to explain. 152 microseconds is the time it takes to the back of the kindney and back, therefore I divide with 2, because I only need one way. I don't need to find the length from the skin to the back of the kidney, so therefore I subtract 75 and 20. Then I multiply seconds I'm left with with the speed through the kidney tissue. I don't see what I have done wrong. Could someone tell me?
 
  • #5
My bad, I should have read the question better. It should be (152-75)/2. Thank's for your help!
 

Related to Ultrasound waves and the kidney

1. What are ultrasound waves and how do they work on the kidney?

Ultrasound waves are high frequency sound waves that are used in medical imaging to create images of internal organs and structures. These waves are directed towards the kidney and are reflected back at different rates depending on the density of the tissue, allowing for the creation of images that can show the size, shape, and function of the kidney.

2. How is ultrasound used to diagnose kidney problems?

Ultrasound can be used to diagnose a variety of kidney problems, including kidney stones, cysts, tumors, and other abnormalities. The images produced by ultrasound can show the location and size of these issues, as well as the blood flow to and from the kidney. This can help doctors identify the cause of symptoms and determine the best course of treatment.

3. Is ultrasound safe for the kidneys?

Ultrasound is considered a safe and non-invasive imaging technique, making it a preferred method for evaluating kidney function. It does not use radiation, so there is no risk of exposure. However, repeated or prolonged use of ultrasound may cause heating of the tissue, so it is important for the ultrasound technician to use the lowest possible intensity for the shortest amount of time necessary.

4. Can ultrasound be used for kidney biopsies?

Yes, ultrasound can be used to guide a needle for a kidney biopsy. This is known as ultrasound-guided biopsy and it allows doctors to precisely target the area of concern in the kidney. This minimally invasive procedure is often preferred over traditional surgical biopsies, as it has a lower risk of complications and a quicker recovery time.

5. Are there any limitations to using ultrasound for kidney imaging?

While ultrasound is a valuable tool for imaging the kidney, it does have some limitations. It may not be able to detect small kidney stones or certain types of tumors. In addition, obesity or excess gas in the intestines can make it difficult to obtain clear images. In these cases, other imaging techniques such as CT scans or MRIs may be necessary.

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