• Object ID: 00000018WIA30591970GYZ
  • Topic ID: id_40021276 Version: 1.5
  • Date: Mar 24, 2022 5:10:57 PM

QuickSTEP

Before you begin

QuickSTEP is a multi-station, multi-phase acquisition technique that minimizes the set-up and acquisition time for lower extremity run-off examinations. The acquisition technique eliminates the need for a localizer scan and employs efficient prescription methods including an auto volume prescription system with specific coils, which reduces the exam time to approximately 6 to 8 minutes.

QuickSTEP uses RF excitation pulses that are much shorter in duration than other excitation RF pulses. Since they encompass the entire thickness of the body, there is no need for scout imaging. The excitation pulses also permit a substantial reduction in TE and TR, resulting in an acquisition time that is very short and it allows for entire body thickness coverage without impairment of spatial resolution.

Figure 1. QuickSTEP lower extremity run-off

About this task

Use these steps to acquire a QuickStep scan. Keep in mind the following:
  • QuickSTEP can only acquire coronal slabs.
  • It is only compatible with the bolus detection method of Fluoro Trigger.
  • Most of the scan parameters are automatically selected with QuickSTEP. If you wish to control the scan parameters, then acquire a 3D FGRE scan with the Multi-Phase and Multi-Station Imaging Options selected.
  • If Multi-Phase is selected, it only applies to Arterial Phase acquisition. Mask and Venous phases remain as single phase scans.

Step-by-step instructions

  1. For patient set-up, follow these steps.
    1. Place a QuickSTEP compatible coil on the table. When a compatible surface coil is used, position the coil used for the last station.
      The QuickSTEP protocol must have a coil that matches the coil on the table. If the coil in the protocol does not match the coil on the table, you cannot use the protocol.
    2. Position the patient supine and feet first.
      The patient must have the arms raised above the head since there is no anti-aliasing option available.
    3. Place the landmark at the feet. The landmark position informs the system where the patient coverage begins.
    4. Inform the patient of the rapid table movement that occurs during the scan so that the patient is not startled when the table moves between stations.
  2. Start a scan session.
  3. From the Workflow Manager, click Add Task > Add Sequence.
  4. From the Protocol screen, select a QuickSTEP protocol from your site or GE library. In the GE library, the QuickSTEP protocols are located in the Abdomen body part.
    1. Select a QuickSTEP protocol from one of the sub-folders that uses the following naming convention:
      QUICKSTEP <coil name><multiphase option>. The MPH option indicates the number of phases for the arterial stage. If there is no MPH in the protocol title, then it implies a single phase scan.
    2. Select one of the protocols from the selected sub-folder that uses the following naming convention:
      • QUICKSTEP <coverage><patient size>. Coverage is the S/I runoff coverage and patient size indicates the FOV, which is based on the patient body habitus.
      • Sample protocol names:
        • QUICKSTEP 128 cm Lrg = 128 cm coverage and a 48 cm FOV
        • QUICKSTEP 112 cm Lrg = 112 cm coverage and a 42 cm FOV
        • QUICKSTEP 128 cm Med = 128 cm coverage and a 48 cm FOV
        • QUICKSTEP 112 cm Med = 112 cm coverage and a 42 cm FOV
        • QUICKSTEP 96 cm Small = 96 cm coverage and a 36 cm FOV
  5. From the Workflow Manager, select the QuickSTEP series and click Setup.
    The Multistation Task screen displays. The number of stations cannot be edited. It is part of the protocol.
    Figure 2. QuickStep and Multistation Task screen
    1. Select desired acquisition types for the exam: Mask to allow subtractions, Venous to acquire venous flow, and Arterial to acquire artery flow.
    2. Skip Prescan On is the default selection for optimum exam speed. This means that prescan data is only acquired from the top station and the other stations have the prescan values calculated from the first station. If you want to acquire prescan data from each station, then select Off for the Skip Prescan option.
    3. Select desired subtraction series that will automatically be generated when the acquisition is finished.
    4. Click Save Rx to close the Multistation Task screen.
  6. Click the folder + icon to open or expand the QuickSTEP series. Review the scan parameters. The only editable field is contrast and AutoVoice. Make changes as needed.
    Figure 3. Click "+" icon to expand the QuickSTEPs
  7. Click the Advanced tab and view the User CV values. Note that they cannot be changed.
  8. If desired, see Add post-process task. Compatible post-process tasks include:
    • Image Enhancement Filters
    • Multi Planar Reconstruction
    • Maximum Intensity Projection
    • Pasting
  9. Click Save Rx.
  10. Repeat steps 5 - 9 for the other stations in the exam.
  11. Click Prescan All.
  12. When Prescan is finished, click Scan Mask.
    • When the mask series is completed, the system pauses.
    • If you decide to skip the mask series, from the Scan menu select Scan A/V.
  13. Set the patient up for the remaining multi-station acquisitions and prepare the patient for the contrast injection.
  14. Click Scan A/V to launch Fluoro Trigger.
  15. From the Fluoro Trigger screen:
    1. Click Subtract, if desired.
    2. Adjust the Delay Time if desired.
    3. Click GO 3D at the appropriate time.
      • Scan continues until all remaining phases are acquired.
      • Subtracted images and source images are populated to the Patient List.
  16. In the Workflow Manager, select the post-processing series and click Run.
    The images can be filmed from the Viewer or Volume Viewer.