• Object ID: 00000018WIA308FD870GYZ
  • Topic ID: id_40022289 Version: 1.2
  • Date: May 10, 2022 2:14:23 AM

PC: 2D Fast Phase Contrast (FastCINE) scan

Fast Phase Contrast adds the following capabilities to the phase contrast pulse sequence:

  • Single slice multi-phase and multi-slice multi-phase capability
  • Shorter TR and TE values
  • Fast cardiac triggered data acquisition
  • Segments k-space for reduced motion artifact
  • Variable receive bandwidth compatibility
  • The sequence is capable of retrospective and prospective cardiac gating

Use Fast 2D Phase Contrast for:

  • cardiac gated multi-phase data set within a breath hold time frame
  • imaging with Flow Analysis
  • imaging as a localizer for gated TOF acquisitions when looking for peak flow in READY View

Consider this information when modifying Fast 2D Phase Contrast scan parameters. For specific scan parameter values, select a protocol from your GE or Site library.

  • Scan selections: 2D mode, Vascular family, Fast 2D Phase Contrast pulse, Cardiac Gating Imaging Option is always selected (it cannot be turned off). Cardiac tab: enter a value for # of phases to reconstruct. This scan mode is often referred to as FastCINE PC.

General

If more than 4 arrhythmia occur for a scan time less than 25 seconds, (a typical breath hold time frame), or 10 arrhythmia in greater than 25 seconds, the scan aborts and posts a message.

For DICOM header information, see DICOM header.

DICOM header information about heart cycle

For 3DCINE-SPGR 3DCINE-FIESTA, 4DFLOW, and 2D FastCINE (including 2D PC FastCINE scans), the DICOM header contains information about the cardiac cycle variations during scan. This allows a better understanding of the heart rate variation of the patient during the scan and can be used to better interpret the results.

  • The heart rate and nominal interval DICOM tags (0018,1088 and 0018,1062) show the mean heart rate/nominal interval during the scan.
  • Additionally, the minimum RR interval, the maximum RR interval, the number of rejected segments due to detected arrhythmia, and the total number of acquired segments during the scan, also are included in the DICOM header (Tags: 0018,1081- 0018,1082- 0018, 1084- 0018,1083, respectively).

Scan Parameters

  • Bandwidth: As the bandwidth decreases, the minimum TE increases which can potentially increase TR and scan time and reduce temporal resolution.
  • Flip angle: As the flip angle increases, there is greater saturation of small, slow flowing vessels.
  • Prospective: To turn on the prospective mode for a Fast 2D Phase Contrast sequence, which can be useful for some cases of arrhythmia, select the Prospective option from the Cardiac tab.
  • VENC: When using Fast 2D Phase Contrast for head or neck CSF flow studies and the patient is positioned head first, if the cardiac waveform has a lot of noise, use a VENC greater than or equal to 5 cm/sec.
  • VPS: When adjusting the Views per Segment on the Cardiac tab, observe the Scan Parameter area to see the effect the change has on the number of cardiac phases and scan time. As the number of views per segment increases, scan time and number of cardiac phases decreases.

User CVs

Click the Advance tab to view the available User CVs. The CVs may vary based on the field strength and selected scan and imaging parameters.

  • Apodization Level
  • Arrhythmia Monitoring
    • 0 or Off, means that the scan does not abort if arrhythmia occur.
    • 1 or On, means the arrhythmia rejection is on but the threshold is off.
    • 2 means that arrhythmia higher than the threshold are rejected. The threshold is set from the Cardiac tab.
  • Flow Quantification Optimization
    • 1 or On improves quantitative flow measurement at the expense of a longer TE time.
  • Magnitude Weighting Mask
    • 0 means that the pixel value from the PC image represents flow velocity measured in mm/second.
    • 1 means that the PC image SNR is enhanced and the pixel value no longer represents flow velocity.