Signal to noise ratio in a CT scanner

Click For Summary
SUMMARY

The discussion centers on calculating the signal-to-noise ratio (SNR) in a CT scanner when specific parameters are altered. The parameters include halving the tube current, increasing the pitch from 0.9 to 1.2, extending the rotation time from 0.75 seconds to 1 second, and doubling the slice width from 1mm to 2mm. The proposed formula for SNR adjustment is sqrt(0.5*(0.75/1)*(1.2/0.9)*2), which reflects the impact of these changes on noise levels. The conclusion emphasizes the importance of understanding the underlying equations related to these adjustments.

PREREQUISITES
  • Understanding of CT scanner operation and parameters
  • Knowledge of signal-to-noise ratio (SNR) calculations
  • Familiarity with the effects of tube current on image quality
  • Basic grasp of pitch and rotation time in CT imaging
NEXT STEPS
  • Research the mathematical equations governing SNR in CT imaging
  • Learn about the impact of tube current on image noise and quality
  • Study the relationship between pitch, rotation time, and image resolution
  • Explore advanced CT imaging techniques and their effects on SNR
USEFUL FOR

This discussion is beneficial for radiology students, medical imaging professionals, and anyone involved in optimizing CT scanner performance and understanding the implications of technical adjustments on image quality.

BobP
Messages
70
Reaction score
1

Homework Statement


If the relative noise (noise divided by signal) in a region of a CT slice is measured to be N what would be the value if the tube current was halved, the pitch increased from 0.9 to 1.2, the rotation time increased from 0.75s to 1s and the slice width increased from 1mm to 2mm.

Homework Equations

The Attempt at a Solution


I think the answer is N
Working: sqrt(0.5*(1/0.75)*(0.9/1.2)*2)
but am not certain
 
Last edited:
Physics news on Phys.org
Doesn't your textbook have any discussion of the influence of any of those changes? There must be some relevant equations. You should learn them.
 
FactChecker said:
Doesn't your textbook have any discussion of the influence of any of those changes? There must be some relevant equations. You should learn them.
My course is entire lecture-based and we were told we didn't need books. as they are so expensive I didn't buy any. I did a google search but couldn't find anything Having said that I realized I probably got two things in the working the wrong way around but the answer is still N? right?
sqrt(0.5*(0.75/1)*(1.2/0.9)*2)
 

Similar threads

  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 24 ·
Replies
24
Views
5K
  • · Replies 75 ·
3
Replies
75
Views
7K
  • · Replies 1 ·
Replies
1
Views
5K
  • · Replies 6 ·
Replies
6
Views
4K
  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 18 ·
Replies
18
Views
12K
  • · Replies 17 ·
Replies
17
Views
4K
  • · Replies 184 ·
7
Replies
184
Views
23K