Acceleration Factor

Select an Acceleration Factor for the scan prescription to reduce scan time. The higher the Acceleration Factor, the shorter the scan time for a given protocol.

• In general, the scan time is reduced by a factor equal to the Acceleration, though this may not be the case for all protocols. For example, an Acceleration of 1.0 results in a 45 second scan which is reduced to approximately 15 seconds when the Acceleration is changed to 3.0.
• For details, see ARC and Acquire a scan with ASSET.
• For details about selecting an ARC factor with MAVRIC SL scans, see MAVRIC SL.
• Higher Acceleration Factors may result in reduced Signal-to-Noise Ratio (SNR) and increased residual aliasing artifacts. For this reason, protocols Acceleration Factor compatible protocols provide a factor called Recommended Acceleration that balances scan time reduction with the potential drawbacks of higher accelerations. The Recommended Acceleration is calculated based on the coil, the imaging plane, the Y resolution and the number of slices. Thus, different protocols might have different Recommended Accelerations.
• There may be occasions where the Recommended Acceleration Factor may not be suitable. For example, if you find that there is insufficient SNR for larger patients at the Recommended Acceleration, consider reducing the Acceleration Factor for large patients.
• Alternatively, there may be patients who are unable to complete a successful breath-hold. In this situation, consider increasing the Acceleration Factor to provide a shorter scan, with the understanding that there is the possibility of reduced SNR or increased residual aliasing.