What is the point of repeating TR signals in MRI

Thread starter gladius999
Start date Jun 1, 2010
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Mri Point Signals

In summary, repeating TR signals in MRI allows for the acquisition of multiple images of the same area, resulting in better visualization and analysis of anatomical structures. It can also improve the signal-to-noise ratio, leading to higher quality images with better contrast and clarity. The TR can be adjusted to optimize image quality for different tissues and imaging sequences, with shorter TR values typically used for T1-weighted images and longer TR values used for T2-weighted images. If the TR is too short or too long, it can negatively impact image quality, making it crucial to carefully select the appropriate TR for each sequence. Additionally, factors such as the strength of the magnetic field, type of radiofrequency pulse, and type of tissue being imaged can

Jun 1, 2010

gladius999

What is the point of repeating the TR 90 degree pulse in MRI? I understand you must modify the TR time to get different T1 times, but since the echo signal is read, would'nt all the echo signals be read to the same intensity after a 90 degree pulse?

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Jun 3, 2010

PhilDSP

Just a guess: you can improve the signal-to-noise ratio by averaging separate FFT results.

1. What is the purpose of repeating TR signals in MRI?

The repetition time (TR) in MRI refers to the time interval between successive radiofrequency pulses in the imaging sequence. Repeating TR signals is necessary to acquire multiple images of the same area, allowing for better visualization and analysis of anatomical structures.

2. How does repeating TR signals affect the quality of MRI images?

Repeating TR signals can improve the signal-to-noise ratio of MRI images, resulting in higher quality images with better contrast and clarity. This is because repeating the TR signals allows for more time for the nuclei to relax and emit a stronger signal.

3. Can repeating TR signals be adjusted in MRI?

Yes, the TR can be adjusted in MRI to optimize the image quality for different tissues and imaging sequences. Shorter TR values are generally used for T1-weighted images, while longer TR values are used for T2-weighted images.

4. What happens if the TR is too short or too long in MRI?

If the TR is too short, the nuclei may not have enough time to relax and emit a strong enough signal, resulting in poor image quality. On the other hand, if the TR is too long, the signal may become too weak and lead to longer scan times. This is why it is important to carefully select the appropriate TR for each imaging sequence.

5. Are there any other factors besides TR that can affect MRI image quality?

Yes, there are several other factors that can affect MRI image quality, such as the strength of the magnetic field, the type of radiofrequency pulse used, and the type of tissue being imaged. These factors must all be carefully controlled and optimized to produce high-quality MRI images.