What is bandwidth in mri

In MRI bandwidth is defined as the amount of frequencies or wavelengths that can be transmitted or received in a limited amount of time. Bandwidth is measured in cycles per second or Hertz (Hz). An MRI sequence is designed with two types of bandwidths: transmitter bandwidth (tBW) and receiver bandwidth (rBW).

1. What is high bandwidth in MRI?
2. What is a narrow bandwidth in MRI?
3. What is narrow vs wide bandwidth MRI?
4. How does bandwidth affect SNR MRI?

What is high bandwidth in MRI?

A higher bandwidth is used for the reduction of chemical shift artifacts (lower bandwidth - more chemical shift - longer dwell time - but better signal to noise ratio). Narrow receive bandwidths accentuate this water fat shift by assigning a smaller number of frequencies across the MRI image.

What is a narrow bandwidth in MRI?

For clinical MRI the term "narrow bandwidth" typically means a setting in the range of 5-20 kHz. Since the distribution of noise is fairly evenly distributed across the entire frequency spectrum, limiting BW reduces the amount of noise mixed in with the signal.

What is narrow vs wide bandwidth MRI?

a broad bandwidth corresponds to a fast sampling of the MR signal and a high-intensity readout gradient. a narrow bandwidth corresponds to a slow sampling of the MR signal and a low-intensity readout gradient.

How does bandwidth affect SNR MRI?

Increasing the receiver bandwidth reduces the SNR. Receiver bandwidth is the amount of frequencies or wavelengths collected during the reception phase (frequency encoding) of RF pulses. Increasing the bandwidth reduces the scan time, susceptibility artefacts and chemical shift artefacts.