USER MANUAL FilmQA™ Pro Version: 3.0.4864.
Table of Contents Introduction 1 Installation 2 Getting Started 7 Operations Menu Bar Case Description Case Data Selector Panel Image Panel Film Evaluation Panel 8 14 14 19 22 Processes Calibration Dose Map Plan to Dose Comparison One Scan Protocol 28 41 50 67 Physics Modules Star Shot Analysis Flatness and Symmetry Analysis Picket Fence Analysis 74 93 96 Editors Bitmap Color Translation Color Translation Map 103 104 Configuration Managing the Libraries 108 Appendices Calibration Protocol Ef
1 INTRODUCTION (Video: http://www.youtube.com/watch?v=A26tTy2iF88) FilmQA™ Pro is a sophisticated, quantitative, analysis tool specifically designed to simplify and streamline your IMRT QA process. The program allows you to scan or open images of exposed application films and calculate the optimized dose maps. The calculation is based on a scanner-dependent function generated from calibrated data derived from three color channels (red, green and blue).
2 INSTALLATION Recommended computer requirements for FilmQA™ Pro: Hardware: Processor: RAM: Graphics: Input Devices: Scanners: i7 8 GB, 1333 MHz UXGA+ (1600 x 1200), HD (1920 x 1080) or WQXGA (2560 x 1600) Keyboard and Mouse [Tablet (Touch screens) not supported] Epson 11000XL and 10000XL with Epson Twain Drivers Minimum computer requirements for FilmQA™ Pro: Hardware: Processor: RAM: Graphics: i5 4 GB, 1333 MHz Wide XGA+ (1440 x 990) XGA+ (1152 x 864) Software: Operating System: Windows 8 Windows 7 [w
3 1. Download and run the installation file from www.filmqapro.com\install. 2.
4 3. “Agree” to the licensing agreement to proceed 4. Click “Next>” to install the necessary files in the selected folder 5. Click “Next>” to complete the installation of FilmQA™ Pro “Close” the window to completed the installation process 6.
5 7. When starting FilmQA™ Pro for the first time, the program will prompt you to generate a license (see the following message below): 8. Click “Ok” and the following window will appear 9. Click “Save” and note the stored key file name and location 10. Email the saved file to amicke@ashland.
6 11. After receiving the license key, save the key to the application folder in either “c:\Program Files\ISP Advanced Materials\FilmQA Pro 20XX\” or “c:\Program Files\Ashland Advanced Materials\FilmQA Pro 20XX\”. NOTE: Only one (1) license key can be stored in the application folder.] 12. Return to the “FilmQA™ Pro” shortcut on your desktop and when you click the icon this time, FilmQA™ Pro will begin.
7 GETTING STARTED (Video: http://www.youtube.com/watch?v=5mAidqhL5qM) When FilmQA™ Pro loads, the following screen will appear: As you can see, there are three sections. To the left is the “Case Data Selector Panel” which allows you to add selected image objects from a saved file or directly from a scanner. This panel contains the case tree and its branches are a collection of the case objects required to execute a case.
8 defined areas of interest and the size and position of a user-defined profile path across an image. Keep in mind that navigating through FilmQA™ Pro is very easy. Using the keyboard and mouse point-and-click commands, you can either left click to select an item or right click to access a drop-down menu. Hovering over any icon will display its name and explain its function. A video MENU BAR At the top of the window is a Menu bar with four tabs: File, Panel, Data and Help.
9 “Configuration” – Loads/saves FilmQA™ Pro configuration settings from a new drop-down list “Auto Save” – Saves the configuration automatically each time you exit the application “Reload Last Case with Configuration” – Opens treatment case with the same configuration that was set the last time the case was opened. “Save File Locations” – Recalls location of saved files “Reset to Default” – Reset the configuration to system default.
10 “Object Type Management” displays the Case Object library allows various objects to be activated and therefore available from the drop down list in the Case Data Selector Panel. User-written functions can be added to the library. “Reset to Default Treatment Object Types” returns the object list back to default settings. “Always include Default Treatment Object Types” is the option to see the default object list all the time.
11 Data, as the name describes, includes all data related to the patient, treatment case or scanner. This tab also allows the changing of measurement units and adjustment of software preferences. “Patient Data” allows you to create a new patient and add or remove a patient from the database. “Treatment Case Data” allows you to create a new treatment case and add or remove a case from the database. “Scanner Data” allows you to add or remove a scanner from the database.
12 predetermined color mixes. Colors can always be returned to default settings by selecting “Reset to Default Colors” “Label Position” changes the location of icons and panel labels to either “Top Left”, “Top Center”, “Top Right”, “Bottom Left”, “Bottom Center” or “Bottom Right”. “Status Bar” is located at the bottom of the screen and does the following: 1. Informs you of the current software condition; 2. Allows changes to be made to the status history; 3.
13 “Reset History” – Clear all events “Word Wrap” – Wrap the words to fit the window width “Filter” (see arrow above) allows you to enter a criterion to reduce the number of visible exceptions in the window. See detailed descriptions and examples in “Menu”. “Status” shows the complete history of conditions since the application was opened. By “right clicking” in the window, options become available to either “Clear Status History”, “Copy All” line items or “Copy a Selected Row” 4.
14 Help is the last category and provides instructional information such as the user’s manual, license data generator, license expiration notification and related web links. “FilmQA Pro User’s Guide” is to view the user manual for the software. “Generate License Data” saves or copies the license data. For details on how to obtain a license key, see Installation (Page 4 – Step #8). “Notify, Before License Expires” monitors and warns the users before the license expires.
15 “Case Data” opens a drop down list to select case specific information related to the patient. Double-click the icon to open the pop-up window and select the preferred case. “Patient Data” will change to match the patient name of the treatment case selected. Case Object Management allows objects to be added to the Case Tree to create a film dosimetry case.
16 By default the first Dose Map in the case is used. In the Dose-to-plan Comparison branch of the Case Tree select a different dependency if the case contains multiple Dose Map Objects and one of the subsequent ones is to be used.
17 Case Data Selector shows the case management tree which allows you to add selected image objects into case data. It is located on the left side of the screen. The case data selector allows you to add patient information, calibration data, and film images and data analysis from a file or directly from a scanner. Remember each object added to the tree is dependent on the objects above it.
18 for some scanner drivers which would auto rotate the image without rotating the device information (e.g. Epson used in conjunction with Windows XP). “Detect whether Scanner Rotates Image” manually forces the detection of image rotation when the automatic feature is disabled. “Scanner Rotates Image” manually forces the scanner to rotate the displayed image 90°. “Options” displays a new window with various choices.
19 IMAGE PANEL Image Panel displays the image and user-defined regions of interest for dose calibration and measurement. It is located at the center of the screen. The image panel allows the users to view the active image and to select the region of interest (ROI) for dose calibration and calculation. Fifteen icons are designated as tools and appear on the bar to the left of the image panel.
20 Color Channel Selector, allows you to select, invert, or gray the color channels of the image displayed. Note: This tool does not change the bitmap of the image. The screen view only changes. Color Range Spreader, allows you to select a range of color channels to apply to the displayed image.
21 Equalized Color Channel Density – divides all color channel densities by a normalized color density. For example when “Equalize Red Density” is selected, all color channel densities are divided by a normalized red density. Other options are to invert , translate or manage the color through densities or maps (See Bitmap Color Translation Editor and Color Translation Maps Editor).
22 FILM EVALUATION PANEL Film Evaluation Panel or “Analysis Window” displays evaluation data for any image or dose map in the Image Panel. The panel has tabs to access eight sub-panels: Info, Cursor, Statistics, Profile, Contour, Iso-map, Surface and Report. Info Panel displays information pertaining to the image (i.e. size, pixel, resolution, and color channel range, memory and scanner information) as well as the sizes and locations of any areas of interest displayed on the image.
23 The color channel spreader, spreads the color so that the selected image region is displayed with a color saturation between 0% and 100%. This feature magnifies differences in color. The color channel selector, selects the combination of red, green and blue color channels for mapping the view of the image region. Statistics Panel shows the dose histogram and the image statistics. Information is displayed for the entire image as well as the image around the cursor.
24 region. To pan out, click and drag from bottom right to top left. Right click and hold to drag the histogram across the data range. Right click inside the graph to: 1) change the units and format for the color channel or probability, 2) copy the table or chart, 3) set a new predefined data range or 4) change the configuration of the graph. The image histogram region dropdown list selects the region of the image displayed in the histogram.
25 The Profile Panel shows the image profile along the userdefined path in the image. Click and drag in the image panel to create an image path. Alternatively click the profile icon on the toolbar and select the type of profile from the menu. Click on the profile icon also to change the width of a profile path. Right-click on the profile path itself to select the axis type from pixels, length or normalized.
26 The Contour Panel displays the iso-line chart of the image for a given set of dose or color channel values (see image on the right). Right clicking inside the chart to copy the image, to change the units or to configure the chart. The legend displays the color palette associated with different dose or color channel values. Again by right clicking, one can change the units as well as add, copy, plaste, open and save a palette. Other options for contour levels are: 1.
27 The Surface Tab displays analysis data in a 3D surface. Options to change perspective, elevation, rotation are also available. The Report Tab configures and formats the case report. The report can be written based on color channel, size and content. The footer of each report always lists the dose distribution comparison functions – gamma, DTA and dose difference. The Case Report can be magnified, saved and printed by using the familiar icons under the chart.
28 CALIBRATION (Video: http://www.youtube.com/watch?v=AKqpsFKprf0) The calibration process uses films irradiated with known doses to generate a calibration table and calculate a set of calibration functions, one for each color channel. These calibration functions correlate the dose values of the exposed films with the color values in the scanned images. This section describes how to use FilmQA™ Pro do a film calibration.
29 There are two ways to introduce calibration data or images into FilmQA™ Pro. Film Calibration (Ordinary) is used when all the calibration films are contained in a single scan as for the One Scan Protocol. Film Calibration (Mosaic) is used when the calibration films are contained in multiple images. In the “Case Data Selector” window, select “Add New Case Object” under the “Case Object Management” heading. From the drop-down menu choose either “Film Calibration (Ordinary)” or “Film Calibration (Mosaic)”.
30 3. Specify the Regions of Interest (ROI) by enabling the “Selection Frame Tool”, from the Tool Bar located in the border to the left of the image panel. The “Selection Frame Tool” allows one or more ROI to be manipulated, i.e. moved, sized and shaped. Be aware that in calibration you are defining the average response of the film and the ROI should cover an area of at least 20 cm 2. Draw a rectangular ROI at the center of one of the exposed film strips and adjust its size.
31 4. The next step is to activate the calibration tool. At the end of the Film Calibration (ordinary) branch of the Case Tree click “Tool – Calibration tool”. The calibration window containing the calibration tool opens on the right of the screen. Film Calibration (mosaic) 1. Click the “+” sign next to “Film calibration (mosaic)” to expand the selection. 2.
32 There are four calibration images in the folder. Open the first calibration image. A thumbnail appears in the previously empty data slot and a new empty slot appears. Repeat by clicking on the empty slot and loading the next image and continue until all four images have been opened. (Note: There is a shortcut to quickly open all four image files simultaneously. Right- click the “Film calibration (mosaic)” heading and choose the first item “Open multiple images from file”.
33 (Note: There are shortcuts to copy and size ROI’s. Highlight an ROI, hold down the “Ctrl” key and then point and click to copy the ROI. By left clicking , you can choose from options to copy and paste multiple ROI’s and/or save them to file. Right click and there are more choices including an option to select an ROI and size/shape all other ROIs in the same way.) 4. At the end of the Film Calibration (mosaic) branch of the Case Tree click “Tool – Calibration tool”.
34 Once all the images are imported, a calibration table and fitting function must be generated. In the bottom right corner of the Film Evaluation Panel, the Color Channel Value icon, appears. Clicking this icon automatically loads the response values for the selected ROIs into a table. (Note: The calibration table could also be populated by typing response values manually or by copying/pasting tabulated data from another application.
35 Options: Provides a menu of options to customize the calibration table The dose values can be entered manually from the keyboard or copied and pasted from a table of values. From the IMRT and RapidArc examples installed with FilmQA™ Pro, the doses, in cGy, are embedded in the names of the image files. The dose values can be entered in any order, since, by default, once the table is full, the dose values/responses are sorted in reverse order depending on the responses in the red color (i.e.
36 Data will not be fitted and no plot will be displayed unless there is exactly one dose value for each row of response values. Note: A chart with data points, but no fitted line for one or more of the channels means that no dose-response correlation could be established for that fitting function. Also, if the chart displays a fit with one or more singularities, choose another fitting function. You cannot use a function containing a singularity.
37 Color reciprocal linear vs. dose: X (D) =A + B / (D-C) where X (D) is the response at dose D and A, B and C are coefficients to be determined. This function is used as the default. Color rational (linear) vs. dose: X (D) = (A + BD) / (D+C) where X (D) is the response at dose D and A, B and C are coefficients to be determined. Color rational (quadratic) vs.
38 For a higher dose ranges, e.g. 0-10 Gy the color rational linear function: X (D) = (A +BD) / (D+C) is often preferred. For even greater dose ranges up to 20, 30 Gy or more, the rational quadratic or cubic functions are preferred. The exponential universal calibration is a generic or pre-shaped function determined by compounding calibration data from many, many production lots of EBT type films.
39 Alternatively, choose “Export” and select “Save as Fixed Calibration” (see red box above). In this case only the calibration will be saved for use in calculating a dose map, but for security, a fixed calibration cannot be edited or revised. Scanner header information is required to save a fixed calibration function To load calibration data saved as a Treatment Case choose “File” on the menu bar and “Load treatment case from file”.
40 Add calibration as color mapping: Adds the calibration function as a tool to convert response values to dose. When this option is invoked, for example in plotting a profile across an image in response space, the profile chart and table will be displayed as dose vs. position as opposed to scanner response vs. position.
41 DOSE MAP (Video: http://www.youtube.com/watch?v=pfcGM3yIHlU) To measure or evaluate a dosimetry film, it is necessary to first scan the film and apply an appropriate calibration function to convert the resulting image into dose space. Once converted to a dose image, FilmQA™ Pro offers an array of quantitative analysis tools to evaluate the dose maps. To work with an exposed application film begin by opening a Calibration Object and developing a calibration function.
42 To demonstrate the dose map calculation, another case object will be added to the example from the previous section, Calibration. Specifically the example adds a Dose Map object to the “Film Calibration (mosaic)” object. Begin by clicking “Add New Case Object” under the Case Object Management heading in the Case Data Selector window. From the dropdown menu select “Dose Map (Single Scan)” and when the dose map object appears in the case tree click “+” to expand the heading.
43 Once the IMRT image has loaded, FilmQA™ Pro by default, uses triple-channel dosimetry and automatically builds a dose map and a consistency map. When the calculations are complete the dose map and consistency map are displayed as thumbnail images under the dose map object branch. Triple-channel dosimetry involves the solution of a non-linear optimization problem for each pixel in an image.
44 Dose map from single channel: Calculates dose for each channel independently Dose map using density reference channel: Dual channel dosimetry – uses the selected channel as the reference. The appropriate choice is to use the channel where the slope of the dose response curve is least. Up to 30 Gy, at least, the blue channel has the lowest slope and is the best choice for the reference channel.
45 User defined dose range: Scales the dose range of the dose map to the user’s values – this is helpful when the film image contains dark areas not related to dose – e.g. pen marks, scanner masks Enforce same dose range for RGB: When checked, the dose range is the same for all color channels Uniformity Map: Click this line to calculate and display the uniformity map. In triple channel dosimetry, the film image is split into dose-dependent and doseindependent parts.
46 Filtering: Contains filters that could be applied to any image data before calculating dose or uniformity maps. Fiducial Detection: Contains options and methods useful in recognizing the placement of fiducial markers Duplicate ‘Dose map (single scan)’: Adds a duplicate copy of the dose map object to the case tree. This option is useful when comparing dose mapping methods or other data treatments.
47 Save all ‘Dose map (single scan)’ images as: Saves the dose film image Save all images of the treatment case as: Saves the film images from all case objects in the case tree. Refresh treatment case tree: Refreshes all calculations in the case tree after one or more parameters have been changed Sort objects: Sorts the case objects according to a number of options. This feature is useful when multiple objects of various types have been added to the case tree without regard to their order.
48 The default when a dose map is calculated is “auto-scaling” and it works well unless the darkest areas in the image are not due to radiation exposure, but rather occur because of ink marks on the film or from a mask used on the scanner. In such a case the apparent dose-range of the image may be much higher than the actual dose range to the film and lead to loss of precision in the dose measurements. The remedy is to scale the dose map using a “User defined dose range”.
49 To change the axis units or to copy the image from the image panel, right-click on the axis of the image to change the the “Axes Type” from pixels (the default) to length in mm or to hide the axis. Right-click in the same place to “Copy chart” or “Copy image” and paste in another location. As soon as a dose image loads and so long as a calibration curve is available in the case, FilmQA™ Pro automatically builds the dose and consistency maps.
50 PLAN TO DOSE COMPARISON (Video: http://www.youtube.com/watch?v=8V0dZJ_mchY) In this Section the comparison of an IMRT treatment plan to a dose map calculated from a patient film is described. The description that follows uses the image and data files provided along with the installation of the FilmQA™ Pro application. It builds on the example contained in the Calibration and Dose Map Sections of this User Manual.
51 The “Data –dose map (read only)” slot could also be populated by copying and pasting image data from a spreadsheet. With the file to be copied on the clipboard right click “Data –dose map (read only)” and select “Paste CSV data as image to ‘dose map’” to load the image. In the panel that then appears enter the scaling ranges defining the physical size of the images and its color or dose scaling range.
52 Scan Image ‘Treatment plan’: Not operative Paste CSV data as image to ‘Treatment plan’: Copy a plan from a spreadsheet to be posted as CSV table. . In the panel that then appears enter the scaling ranges defining the physical size of the image and its color or dose scaling range. For the example select “Open treatment plan” go to the folder Program Files/Ashland Advanced Materials/FilmQA Pro 2013/Image/Example EBT2 IMRT and look for Pinnacle format files with extension *.header and *.text.
53 versions of the film itself (e.g. EBT3F or EBT3P) or scribed onto the patient film with pen by a user at the time the film was exposed. The fiducial marks delineate the in-plane and transverse axes of the treatment system as indicated by the projection of the lightfield onto the film.
54 The fiducial marks may have been highlighted when the dose map was calculated or the highlighting could be added at this stagewith the Fiducial marker tool. Notice that the rough alignment of this image is now correct, Then click the icon and “Image fiducial type” and select “General fiducial point”. Point the cursor at the black fiducial mark at the top of the image near the center and click.
55 display in the Image Panel at this stage reveals the fiducial marks on the dose map are not aligned with the longitudinal and tranverse axes. Note: If the case contains multiple dose maps, the correct one must be selected. Click on “Dependence” (5th line along the branch) and choose which Dose Map to use from the drop-down list. By default, a large Region of Interest (ROI) for quantitative evaluation is preselected.
56 horizontally, vertically and rotationally”,the dose map is automatically aligned with the in-plane and transverse axes and thereby with the treatment plan. To manually align the dose map and treatment plan, click the Image Movement icon, on the toolbar to activate the tool. A little arrow appearing in the icon indicates the tool is active - . Click the icon below Image Movement icon to toggle between coarse movement movement , or fine .
57 bottom of the Image Window when the Image movement tool is active. For translational movement click the arrows on the large square button or turn the circular knob for rotation. Alternatively the motions can be controlled by clicking either of the large buttons and using the keyboard arrows. For relative dosimetry the maximum dose value in the treatment plan can be scale up or down.
58 Click on the icon to choose the type of gamma map select between Gamma relative error, Gamma Normalized or Gamma Angle. Click on the icon and from the menu select whether the required tolerance value is set relative to the maximum dose in the plan, relative to the plan value for the pixel in question or relative to a user-defined value.
59 In the example Case the gamma test passing rate is >99.6% for 3% dose tolerance at 3 mm. Passing rates >99% for the 3%/3mm criteria are common with film evaluation, but with passing rates that high, there is little sensitivity in using the passing rate to search for a more optimal fit while using the coarse 3%/3mm evaluation criteria.
60 Note: For absolute dosimetry, do NOT adjust the maximum dose in the plan image. Maximum dose could be adjusted when doing relative dosimetry. Small position adjustments of x = - 0.3 mm; y = -0.6mm and rotation by -0.2° move the passing rate from 95.11% to 96.4%. Clicking the icon assigns the analysis map (gamma map in the example) as a Treatment Object within the Dose to plan comparison Object. Note: If the analysis function values do not update after changes click the icon to force an update.
61 Right click anywhere in the chart to access another set of selections for the chart display and control the values along x and y axes, format the units, show a probability histogram or cumulative histogram and change the number of data clusters for the histogram display. Note: Click the command line “Display mode” and activate one of the choices to display a histogram table in addition to the chart.
62 6. Full horizontal line: User sets the position of a horizontal line across the entire image 7. Circle: User defines a circular path 8. Ellipse: User defines an elliptical path 9. Options: Presents options for the way in which the profile path is displayed 10. Path range width: User defines the width of thew profile path 11. Copy path: Path can be copied for pasting on another image in the Image Panel 12. Add current path to recent list: Saves the selected path to file for later use 13.
63 slider controls translation along the x and y axes. There is an option to limit the profile path to the envelope of the Selection Frame (Region of interest). The Isolines Tab displays an overlay of the isodose lines between the treatment plan and dose map. It is a very useful display when making manual adjustments of the rotational and translational position of the measurements relative to the plan. Right click anywhere on the isolines chart to show a menu of display choices for the chart.
64 Use the to save or copy the Contour Level Palette or retrieve a saved Contour Level Palette. The Isomap Tab displays the isomap of the gamma function. A legend describes the variances of the dose. The Surface Tab displays the analysis data on a 3-D surface.
65 The Delta Map Tab shows the passing rates (gamma analysis in the example) for the all three color channels below the chart. The chart in the window displays the pass/fail data for the red, green and blue color channels in map form. Pixels passing the gamma test in all three channels are dispayed in black. If a pixel fails the gamma test for a particular channel it is displayed in that color or mix of colors. White indicates areas where all three channels fail the gamma test.
66 generates a projection map, i.e. the measured dose map is recalculated by averaging individual pixels values grouped to reproduce the spatial resolution of the plan. The projection map is displayed in the projection tab. The projection map can be exported either as an image file or a CSV table to other applications. Icons along the left hand border of the window give access to tools available in the Image Panel and described in that section. The Report Tab configures and formats the case report.
67 ONE SCAN PROTOCOL This efficient protocol was developed to simplify radiochromic film calibration and to avoid the complications of the post-exposure growth of radiochromic film response and the scan-to-scan variability of the scanner. The protocol provides a time-saving method for evaluating radiotherapy treatment plans. The protocol combines calibration and measurement in a single scan. It was published in Medical Physics, 39(10), pp 6339, 2012.
68 reference film, one reference film exposed to a known dose of radiation in addition to the exposed application film. Note: All films used for the One Scan Protocol must be from the same production lot and from the same production lot as the films used for the primary calibration. The illustration shows an application film is shown with two reference strips above it. The upper strip is the unexposed film and the lower strip is the one exposed to a known dose.
69 to film orientation, but it is also means that a calibration with three or four exposures can be done with less than one sheet of film. Although this example doesn't conform to the rule, it works best to have the doses in approximate geometric progression rather than in arithmetic progression. Use the Frame Selector tool to draw areas of interest in the center of each strip. A frame can be easily duplicated by holding down the "Control" key and pointing/clicking with the mouse.
70 Use the Calibration Statistics icon to display a table of calibration statistics in the Image Window. This table of consistency values determined from the measured calibration doses and the fitted values and helps in selecting the best fitting function for the data points. Lower values in the table signify a better fit. In most cases with doses <500 cGy, the best fitting function is the rational (linear) function. For a higher dose ranges, e.g.
71 Point the cursor and click on each fiducial mark to add highlight marks. The fiducial fitting senses the center of the highlight marks, not the marks scribed on the film. For precise adjustment click on a highlight, press the Control key and use the keyboard arrows to move the mark. When FilmQA™ Pro has finished calculating the dose map (using multi-channel dosimetry), select the dose map and draw areas of interest at the center of the two reference strips.
72 Here’s where the One Scan Protocol can be applied. Display the image of the application and reference films in the Image Panel and draw an area of interest on the unexposed reference strip. Then right click the region to designate it a calibration region and right click again on the frame to type in and enter the calibration value of zero. Notice that the frame changes color from yellow to blue to indicate it’s a calibration region.
73 Display the new dose map in the Image Window and look at the values in the Statistics table. The exposed reference film is now exactly 313 cGy in each color channel. For the unexposed film the tabulated values are not exactly zero, but only because FilmQA™ Pro doesn’t display negative dose values. Any negative calculated value is set to zero as shown by the histogram.
74 STAR SHOT ANALYSIS I. (Video: http://www.youtube.com/watch?v=CPtz-0dHbR8) SCOPE The protocol applies to GafChromic™ EBT2, EBT3 and EBT3+ films exposed on a linear accelerator and analyzed using FilmQA™ Pro software. It provides an efficient method for evaluating the isocenter position of linear accelerators using the star shot test. The exposed films are scanned on an Epson ® 10000XL or 11000XL scanner in either transmission of reflection mode.
75 strip for another use. The best way to tear EBT3+ is to grip the edge of the film as close as possible on either side of the perforation. Push down on one side and pull up on the other to start a tear and split the film into two pieces. A. Gantry Star Shot 1. Tape a sheet of film at the center of the large face of one of the plastic slabs with the edges of the film and the slab roughly parallel to one another. 2.
76 film with 150 MU at each position. Note: The ideal dose to the film for each beam is 100–200 cGy. Adjustment of MU should be made to achieve the aim. 7. Separate the slabs. Take the one to which the film is attached and use a fine-tip pen, a ruler and the marks on the slab (see Step 4) transfer the transverse line indicating isocenter height to the edges of the film. Remove the film from the slab and proceed to Scanning and Star shot Image Analysis, Step D1.
77 B. Collimator Star Shot 1. Tape a sheet of film at the center of one of the plastic slabs with the edges of the film and the slab roughly parallel to one another. 2. Place the slab under the collimator with the film on top and the long edge of the film roughly parallel to the longitudinal axis and the center of the film roughly at isocenter. 3. Using the laser lines and light field markers adjust the couch height and slab/film position so the film is level and at isocenter.
78 Figure 2: Collimator star shot C. Couch Star Shot 1. Tape a sheet of film at the center of one of the plastic slabs with the edges of the film and the slab roughly parallel to one another. 2. Place the slab under the head of the linac with the film on top and the long edge of the film roughly parallel to the longitudinal axis and the center of the film roughly at isocenter. 3.
79 analysis in the following ways. As the slit becomes narrower more monitor units may be required to obtain the same darkening of the film. Widening the slit may reduce the accuracy and precision of the analysis because the lines will be less sharp. Note: For the couch star shot no build-up slab is used on top of the film. In the absence of the build-up material the effect of scattered radiation will be reduced and exposed lines will be sharper.
80 Figure 3: FilmQA™ Pro – Opening screen 2.
81 3. Expand the MLC Starshot Physics Case Object and right click on “Data starshot #1 (empty)”. Click on “Scan Image starshot #1”. Alternately an image could be loaded by selecting “Open image starshot #1 from file”. Opening Epson Scan utility to scan an image 4. Next, the Epson® Driver window appears.
82 Incorrect! Color correction must be turned off. Correct! Color correction is not active Open Configuration window and check “No color correction” Figure 4A Figure 4B Figure 4C 5. Put the star shot film in the center of the scanner and scan it. The analysis does not involve dosimetry so no warm-up scans are required and the film can be placed in any orientation.
83 Figure 5: Gantry starshot film image and selection of vertical fiducial mark Figure 6: Gantry starshot with software fiducial marks in place 6. Click on “Tool – starshot physics QA” to activate the analysis. The fiducial marks should automatically align with the axes in the display, but if they do not – as shown in Figure 7 – click on the . icon and select “Fit fiducials horizontally, vertically and rotationally”. The aligned image is shown in Figure 8.
84 Figure 7 .
85 At this point the analysis is complete although small adjustments could be made by refining the default settings as described in the following steps 7 and 8. The diameter of the analysis circles: In general, the larger circle should extend almost to the end of the beam lines, but be within fiducial marks. In the gantry starshot the beam lines extend the film edge so the larger circle could be 15 cm, or more, in diameter. The smaller circle should be ¼ to ½ the diameter of the large circle.
86 intersection points has a radius of 1.3mm and the centroid formed by the intersection points is 0.8mm from isocenter. Adjust the diameter and width of the circles by suing the sliders at the bottonm of the Image window. Figure 9 8. As shown in figure below, right-click the icon underneath the chart in the Analysis Window and select the option to restrict the analysis to intersection angles >25°.
87 The result (Figure 10) shows that 27 of 35 intersection points were used. The radius of the minimum circle encompassing all intersections is reduced to 0.7 mm. The intersection-point centroid is still 0.8 mm from isocenter. Figure 10 The blue arrows move the image clipping region in the desired direction selected. These buttons (right) set the size and scale of the display chart and the position of the information displayed (clipping region).
88 E. Analysis Circle Profile 1. Click on the “Profile” tab (see below) to display a profile along the paths of the two analysis circles as well as the intersection points determined by the analysis. Click to display profiles Profiles along analysis paths and intersection points Profiling along the analysis path verifies the quality of the detected intersection points between the beam lines and analysis circles.
89 pixel data. This tab will display the profile data along the analysis circles and the detected minima points (center of the beam lines). The “Profile Normalization” button, toggles between normalized data and color channel value data. The “Copy” button, copies current chart settings to the reporting tool. F. Report The Report feature of FilmQA™ Pro is accessed under the Report tab along the border between the Analysis Window and Image Panel.
90 3. “Report Options”, , opens a pop-up window so the user can: “Open/Save Document Template” – Loads or saves report settings “Show Report Parameters” – Shows or hides report parameter controls “Number of Viewed Pages” – Selects fixed or floating number of pages per page section. Default is set as float. 4. “Print”, sends the report to a printer. Printer selection dialog will appear. 5.
91 noise is reduced by using relatively wider path widths with the provision not to include areas beyond the length of the exposed beam lines nor encroach upon the area of higher exposure where the beams cross near the isocenter. Right-click the icon in the bottom right corner of the Image Window (see right) to reveal a menu of analysis options: 1.
92 5. Extrema cut-off limit: the tolerance for extrema inclusion. Choices are 0, 3, 5, 10, 15, 20, 30, 40, 50, 70 and 100%. 6. Profile start angle: The start of the circular analysis paths must not coincide with the center of a beam line. The default is -26° since it is very unlikely that a beam line will fall at that angle, but another starting point could be selected. 7.
93 FLATNESS AND SYMMETRY ANALYSIS Click on “Add New Case Object” under the “Case Object Management” heading. A drop-down menu will appear and give you several options. Select “Flatness and Symmetry Physics QA” (Shown left). There are two types of objects to select: ‘Flatness and Symmetry Physics QA’ can hold any number of images to be analyzed and uses the images directly. ‘Flatness and Symmetry Physics QA (Dose Map)’ analyzes only a single image that will be converted into a dose map.
94 The flatness and symmetry tool automatically assigns the horizontal and vertical analysis path lines. Use the analysis configuration tool, to make the analysis include used analysis path lines. The detected results may depend on the average width of the chosen analysis path lines (average perpendicular to the path direction) and the color channel used to analyze the image data.
95 The maximum or CAX value can be normalized between 0 and 1. If the base line of the profile is disturbed (left and right values are different), the base line can be equalized using a linear adjustment. If you choose to “Show Analysis Data”, the flatness region as well as the penumbra areas are marked in the chart as shown right. When the analysis is completed, select the “Report” tab to summarize the results for the record.
96 PICKET FENCE ANALYSIS Click on “Add New Case Object” under the “Case Object Management” heading. A drop-down menu will appear and give you several options. Select “MLC Picket Fence Physics QA” (Shown left). Next, acquire the image by either reading it from a saved file or scanning it directly. For automated image registration, select the fiducial tool, and mark the fiducial positions on the image as shown right. Any number of fiducials can be used to identify the isocenter.
97 The picket fence analysis tools automatically detects the beam lines and displays the detected beam line points at the analysis path lines as shown above in the center section. The beam line detection uses the selected region of the interest (green dashed rectangle) to analyze the image data. Select the frame icon, to make this region of interest editable. Click and drag the border lines so that only beam lines are covered.
98 The next step is the MLC Design. For this example, the Varian Millennium 80 MLC is used. Select the MLC Design using the icon. If the targeted MLC design is not available, then use “Create MLC Template Manually” to input new data. When the MLC design is selected, the overlay is displayed in the center section. Use the blue arrow keys to adjust the image position relative to the MLC.
99 Adjustments are complete when the leaf borders on the film line up with the overlaid MLC leaf borders (solid blue lines, dotted blue line are leaf center lines). The space around the leaf center line is used to create profiles to detect the leaf openings as extrema. Select the “Leaf Analysis” tab to commence the analysis. The upper part of the leaf analysis shows the profiles along the center lines for the selected leaf and beam ranges (bottom row).
100 To account for such deviation, FilmQA™ Pro offers the following profile normalization options: Normalize global minimum and maximum to 0 and 1: Global extrema for each leaf center profile are normalized to 0 and 1 to account for small drifts across the image. Equalize all local minima and maxima to 0 and 1: Normalization changes for each beam and leaf extrema pair and equalizes all profile sections. All maxima are at 1 and all minima are at 0.
101 Truncate at smallest local minimum and maximum values and normalize to 0 and 1: Truncate lower part of the profile at highest minimum and upper part of the profile at lowest maximum and then normalize resulting profile to 0 and 1. This approach is very advantageous especially when the leaf openings vary over a wide range (i.e. the dose varies a lot between the leaf openings). Use the button to select the normalization mode for the profiles you require.
102 When the analysis is complete, select the “Report” tab to summarize the results of the case. Enable items that should be included in the report and add information to identify the test in the footer of the report.
103 EDITORS The Bitmap Color Translation Editor is the first editor and allows the user to create, edit and delete color translations to the image. The bitmap color translation editor can be accessed under the statistics and profile panels. The “preview” panel displays the image before and after the color translation is applied. Right click inside the image to change the color channel and image size.
104 The “color translation list” shows a list of color translations that are available at the working panel. The user can view, select and delete color translations on the list The “image selector” is a drop down list to select the image being tested with the color translation effect. The “color translation name” window permits the user to create, view or change the name of the color translation selected. The “displayed color selector”, shows colors and its effect in the “preview” panel.
105 Figure 1 2. Enter the name and description of the color map. If necessary, the color icon can be changed (see below).
106 3. Color translations can be mapped to any image. When such translations are needed, one can access them via the “Color Translation Tool”, in the Image Panel. 4. Select “Manage color translation maps” to open the “Color Translation Maps Editor” which allows you to manage such non-linear (non-matrix) translations.
107 The “Preview” panel allows you to view the image before and after the translation is applied. Right click inside the panel to change the displayed color channel and the image size. Drop-down list of images to test and preview the color translation editor The “Color Translations Panel” lists all the color translations available. One can view, select, and delete the color translations in this list.
108 CONFIGURATION FilmQA™ Pro has an extensive library of functional subroutines to execute an array of tasks in radiochromic film dosimetry and QA tests. While not every function in the library is activated and given default availability, it is very simple to add inactive tools, treatment objects, plans readers, etc. to the active list as demonstrated by the following example. Click “Panel” on the menu bar and select “Treatment object management” and then “Object type management” from the context menus.
109 To add a treatment object to the active list, click on the object to highlight it. Then click the icon between the two lists to transfer the object and finally click the process by clicking the . Reverse icon to remove an item from the active list.
110 TROUBLESHOOTING Installation Issues: 1. Make sure security programs or virus scanners are disabled prior to installing. 2. If program does not load, check if .NET Framework 4.0 is installed. Client version will NOT work. The full version must be installed. 3. When using Windows 7, make sure that .NETFramework 4.0 is installed. If .NETFramework 4.0 is installed then check whether the write permission is enabled for the FilmQA™ Pro folder.
111 Film Issues: 1. When using the EPSON V700 Photo scanner, remove film after scanning is complete. Unlike the EPSON 10000XL, the lamp stays on and could affect the film if in contact with light for longs periods of time. Operating Issues: 1. If the error “Valid License Is Not Granted” occurs, make sure you have generated a license request (LicenseRequestData_xxx_20120605.txt) and submit it to amicke@ashland.com. When the license key is emailed back to you, copy the file (BaseLicenseGrant_xxx.
112 7. During a “Film Calibration – Mosaic” if many large strips are being used, the images may need to be cropped. Too many strips could result in no image or an image that doesn’t reflect all the selected regions of interest. 8. While FilmQA™ Pro supports most image formats, importing lower resolution image formats (i.e. JPEG) is not recommended. Too much information is lost with those images. For quantitative analysis, importing a TIFF file is recommended. 9.
113 Appendix A Calibration Protocol for Radiochromic Film I. PURPOSE To define an efficient protocol for calibration of radiochromic dosimetry film. II. SCOPE The calibration protocol applies to Gafchromic™ EBT2 and EBT3 films at doses up to about 10 Gy. The resulting calibration is intended for use with a radiochromic film dosimetry protocol. The calibration protocol requires a minimum time to elapse between exposure of the films and scanning.
114 Figure 1 Contrast this to the behavior when the same data is fitted to polynomial functions (in this case 4th order) as shown in Figure 2. Obviously the polynomial functions don’t behave like film – film doesn’t get lighter in color and more transparent at high doses. Also, polynomial functions are unacceptable because they oscillate between dose values.
115 The benefit of using the type of rational function described above is that you can actually reduce the number of dose points required for calibration. Figure 3 shows the fit when four of the data points were removed. It is almost identical to the fit in Figure 1 with seven data points. The function has three constants a, b and c and is fully defined with three data points – two films exposed to known doses plus one unexposed film. Figure 3 IV.
116 V. PROCEDURE The film sizes could be 1.5” x 8” strips, or 8” x 10” sheets or anything between. If multiple films are used they must have the same lot number. When cutting strips be certain that the orientation is known with respect to the sheet from which they were obtained. The radiation source is provided as the means for delivering known exposure doses to the calibration and application films.
117 2. Expose the calibration film to a known dose about 30% greater than the highest dose expected for an application film. One way is to use a linear accelerator to expose a 10 cm x 10 cm, but the choice is up to the user. The goal is to create a large area of uniform exposure on the film. Note the time of the exposure. Remove the film and keep it where it is not exposed to light. 3. Repeat Step 1using another film from the same production lot.
118 Figure 1 6. Expand the Film Calibration case object, right click on “Data Calibration Film (empty)” and select and click “Scan Image Calibration Film” (Figure 2). The Epson Driver Window will appear. Choose the settings shown in Figure 3C. If the color correction icons are active (red arrow in Figure 3A), they must be deactivated. Open the Configuration window (Figure 3B) and check “No Color Correction”. The icons should appear gray (green arrow below, right). Note: Resolution of 72 dpi is suggested.
119 Incorrect! Color correction must be turned off. Correct! Color correction is not active Open Configuration window and check “No color correction” Figure 3A Figure 3B Figure 3C 7. Place the calibration films and an unexposed film from the same lot on the scanner as shown in Figure 4. The time between film exposure and scanning is related to the time window within which the calibration strip and application film were exposed. Your efficiency increases when you minimize the time window.
120 8. Use the Frame Tool to mark areas of interest in the centers of the calibration strips (Figure 5). Select areas of interest in center of calibration strips Figure 5 9. Click the “123” icon on the bottom right corner (Figure 6A). Select the “Color reciprocal linear vs. dose” fitting function (Figure 6B) and type in the dose values into the calibration table. “123” icon Figure 6A Figure 6B 10.
121 applicable to other films from the same production lot scanned on the same scanner.
122 APPENDIX B An Efficient Protocol for Radiochromic Film Dosimetry I. PURPOSE To define a radiochromic film dosimetry protocol to measure radiation dose distributions for comparison with a radiotherapy treatment plan. II. SCOPE The protocol applies to Gafchromic™ EBT2 and EBT3 films exposed on a linear accelerator. The object is to provide a time-efficient method for evaluating radiotherapy treatment plans.
123 Epson ® Scanner Software FilmQA™ Pro Software IV. PROCEDURE Films used in this protocol are of two sorts, strips and sheets. Strips are used for calibration exposures and about 4 x 20.3 cm. These strips can be cut from sheets of film taking care to keep track of orientation so all films can be scanned in the same orientation. Sheets are used for plan exposures and can be 20.3 x 25.4 cm sheets or smaller sizes large enough to accept the plan exposures.
124 3. Expose the phantom/film to the chosen radiotherapy treatment plan and note the time. Remove the application film from the phantom. Keep it where it is not exposed to light. 4. Choose a calibration film strip from the same production lot as the application film. Place it in the phantom with the center of the strip close to the center of the exposure area. Fix the film with adhesive tape and place phantom material above the film as required. 5.
125 Figure 1 7.
126 8. Expand the Dose Map selection. Right click “Data - dose film” choosing “Scan Image ‘dose film’” from the drop down menu. The Epson® Driver Window will appear. Choose the settings shown in Figure 3C. If the color correction icons are active (red arrow in Figure 3A) they must be de-activated. Open the Configuration window (Figure 3B) and check “No Color Correction”. The icons should appear gray (green arrow below, right). Note: Resolution of 72 dpi is suggested.
127 Calibration area Keep first 2 cm clear of film Start of scan Scan Direction Direction Position the films in the center (left-to-right) of the scan window Figure 4 10. Use the Frame Tool to select areas of interest in the centers of the calibration strips.
128 11. Right click the areas of interest (Figure 6A) to name the region types as “Calibration Region”. Then right click the regions, select “Calibration Value” (Figure 6B), type in the dose, press “enter” and then “OK” (Figure 6C). Figure 6A Figure 6B Figure 6C 12. Right click on “Dose map single scan” and select “Dose mapping method”, “Recalibration using reference regions” and “Dose linear scaling” (Figure 7A). Again right click on “Dose map single scan” and select “Rebuild Dose Map” (Figure 7B).
129 Figure 7A Figure 7B 13. Compare the measurements with the plan. Add a New Case Object – “Dose to Plan Comparison” (Figure 8A). Then right click “Data Treatment Plan”, navigate to the right folder and open the treatment plan (Figure 8B). Now click on the Image Comparer tool. The treatment plan and dose map appear in the window. Figure 8A Figure 8B Use the tools along the left hand border to select an area of interest around the treatment plan and then align the dose map to the plan.
130 Tabs to display different maps and other types of analysis data Tools to manipulate the dose map and plan Tools to move the dose map relative to the plan Tabs to access different types of analysis and display types of data Figure 9 Tabs on the left edge of the right frame (Figure 9) change the display type in the right window: Statistics, Profile, Isolines, Isomap, Map, Projection or Report.
131 APPENDIX C Post-Exposure Change Exposure of radiochromic film to ionizing radiation starts a solid-state polymerization in crystals of the active component. Polymer grows within the crystal matrix of the monomer. Interatomic distances in the polymer are shorter than in the monomer causing the gap between the end of the growing polymer chain and the next monomer molecule to increase as polymerization progresses. Consequently the rate of polymerization decreases with time.
132 From the data in Figure B-1, it is calculated that at time-after-exposure of 30 minutes, a 5-minute timing difference could contribute to a dose error of about 0.3%, while a 10 minute timing difference could contribute to a dose error about 0.6%. As time-afterexposure increases from 30 to 60 minutes the dose error contributed by a given timing difference decreases by a factor of two. To ensure that time-after-exposure differences have a small contribution to dose error i.e. (<0.
133 Index A B Beam Line Detection Bitmap Color Translation Editor C Calibration Case Data Selector Case Description Client Image Movement Color Translation Editor Colors Configuration Cursor Panel D Data Delta Map Dependency Dose Map 97 103 N Number Format Buttons 28 14 14 55 104 11 108 22 11 65 15 41 E F File Film Evaluation Panel Fitting Function Flatness Fonts G Generating a Response Curve Getting Started H Help Histogram Range I Image Comparer Panel Image Histogram Region Image Panel Info Panel Ins
