• Topic ID: id_16157800
  • Version: 2.0
  • Date: Nov 7, 2019 8:54:45 PM

Streak Test

Prerequisites

Overview

This document provides the necessary steps to test for streak artifacts.

1 Phantom Setup

Procedure

  1. Install all gantry covers and scan window.
  2. Move table to home longitudinal position.
  3. Attach phantom holder to gantry end of cradle.
  4. Mount and center phantom to phantom holder.
  5. Place bubble level on top of phantom, positioned along the Z-axis. Adjust phantom holder back knob until phantom is level front to back.
  6. Turn on laser alignment lights.
  7. Move table into gantry until axial internal alignment lights are lined up with phantom's axial reference mark.
  8. On the console, select SCANNER UTILITIES from the bottom of the Scan Monitor.
  9. Select CENTER PHANTOM from the Scanner Utilities window.
  10. Select CONFIRM in the Phantom Centering window.
  11. Press START] on SCIM when it flashes. A Phantom Centering scan is performed.
  12. Adjust phantom position if results are out of specification range.
    note:

    The phantom center specification is ± 0.5mm.

  13. Repeat steps [10] – [12] until phantom is centered.
  14. Once phantom is centered, press DONE in the Phantom Centering window.
  15. Press QUIT in the Scanner Utilities window.
  16. Set Internal Landmark.

2 Acquire Scans

Procedure

  1. Click NEW PATIENT from the bottom of the Scan Monitor.
  2. Type the following entries in the listed Patient Information fields:
    1. Patient ID: Service
    2. Patient Name: Streak Test
  3. From the Protocol Selection display, click on the Anatomical Selector Service tab.
  4. On the Service Protocol Selection window, select IMAGE QUALITY, 44.1 STREAK TEST.
    note:

    Make sure the prescription is a single group axial protocol.

  5. Select CONFIRM. An Attention message box is displayed.
  6. Click CONTINUE in the Attention message box.
  7. Press START on the SCIM when it flashes. Scans are performed.
  8. When all the scans are completed, click END EXAM.
  9. If a PPS Response window is displayed, click COMPLETE.

3 Image Review

Procedure

  1. From the IMAGEWORKS desktop List/Select browser, select the scanned examination.
  2. Select VIEWER and review all images from the scanned examination for streak artifacts.
  3. If any images depict streaks, perform the steps in Section 4.4 on those images.

4 Streak Analysis

Procedure

  1. Select SERVICE desktop and move the Service Desktop window to the left monitor.
  2. Select IMAGE QUALITY from the Service Desktop.
  3. Select IMAGE ANALYSIS and move IMAGE ANALYSIS window to the left monitor.
  4. From the List/Select browser on the right monitor, select the image to be analyzed.
  5. Click theMANUAL radio button on the Image Analysis window.
  6. Click the MANUAL selection button, and select STREAK.
  7. Click ACCEPT. The image is displayed in the Image Analysis window with a Streak ROI.
  8. Follow instructions, in Image Analysis window lower right pane, to size Streak ROI and analyze.
  9. From the results, if the Measured Streak Factor is out of the specification range of +/-4.0, perform appropriate corrective action.
  10. When all tests are completed, click QUIT.

5 Finalization

No finalization steps.