The QA Check document consists of 2 pages. Page 1 organizes all of the information needed to perform a basic QA check calculation in a tabular format. You may optionally set a "red-yellow-green" alert threshold, and, space permitting, include a picture of the plaque with slot index labels on page 1. Page 2 presents an interactive 3D view of the plaque, tumor, base margin and the selected QA check point in the plaque's coordinate system.

QA document page 1: Check point calculations

Click images to enarge.

QACheckPage1
QACheckTable

The QA_Check calculation is an independently coded, simplified version of Plaque Simulator's (PS) full dose calculation in that it assumes the seeds are isotropic point sources in water.

Page 1 of this document provides a table of source center coordinates and distances between those centers and a user selectable QA_Check point. The default QA_Check point is located 6 mm (customizable in QA preferences) from the face (concave surface) of the plaque on the plaque's Central AXis (CAX). Other options are the Rx point or one of the 16 user definable points of interest (POIs).

The table also includes the other TG43 parameters required to complete a manual confirmation of Plaque Simulator's QA_Check calculation.

Note: In addition to the QA_Check dose calculation, this document also includes a QA_Point calculation which incorporates all of the PS dose calculation parameters (e.g. anisotropic linear sources with other various corrections) that is currently currently selected in the Rx window. The QA_Point dose will typically be 3% to 7% less than the QA_Check dose for EP plaques, and may be up to 15% less for COMS plaques due to increased attenuation in the COMS silicone seed carrier compared to water. You can customize the QA_Point/QA_Check ratio (e.g. default is 0.85) that will trigger an alert in the form of a background color change. If the ratio drops below 0.85 the background color will change from green to yellow. At .05 below the threshold the background color will change to red.

TSVTemplateFolder
QACheckTable

When the QA Check document is being displayed in the Document Preview window you may copy the QA table data in Tab Separated Value (TSV) format to the OSX clipboard from the Edit menu for use with other programs.

Example Excel spreadsheet templates for Eye Physics plaques which verify the calculation of the distance (r) from a seed center to the QA point on the plaque axis at (6.0,0.0,0.0) and the resulting QA_Check dose in Gy are installed in the Quality Assurance folder. Simply open the appropriate template in Excel and paste the previously copied TSV data.

TSVTemplate
TSVTemplateWithData

You may optionally export the same QA data as a TSV file from the Document Menu for use with other programs or for transfer to another computer.

  • The print buttons at the upper left of the window initiate either single document or document group printing.
  • The checkboxes below the document selection buttons at the top of the window indicate which documents will be included in group printing.
  • You can customize a document by clicking the Options button, by double-clicking in the middle of the document window.

  • QA document page 2: Check point geometry

    Page 2 presents an interactive 3D view of the plaque, tumor, base margin and the selected QA check point in the plaque's coordinate system. You can use the cursor virtual track-ball directly on the 3D picture to rotate it (just as in the 3D Setup window), or use the axes constrained rotation buttons in the QA document preferences group (found in the Misc Preferences pane) to best illustrate the geometry of the plaque, tumor, base margin and QA check point.

    QADocPage2

    QA document preferences are found in the Misc Preferences pane DocOptionsMisc