AutoQA Plus CT
CT ACR 464 Gammex Phantom now included in the list of supported CT phantoms!
New Application Highlights
- Designed for simple and intuitive navigation
- Pass/Fail performance evaluation
- User can create Report Profiles to control Pass/Fail limits, output of images, overlays and graphs
- Instant trend analysis using our HTML ‘Trend Report Links’
- Reports available in HTML, PDF and JSON formats
- Support local date and number formats
- Multiple language support
- Simple database export to Excel
- Supports compressed and enhanced DICOM images
- Self-service option for offline license activation
- Import/Export Report Profiles between users
- 'Import/Export processed reports/data between users
Image Quality Parameters Evaluated
- Pixel size (geometric distortion)
- CT Number Linearity (Sensitometry)
- Slice Thickness
- Patient Alignment System and Table Movement Accuracy
- Spatial resolution (MTF)
- Image Uniformity and Noise
- Uniformity Index
- Contrast Detail (Low Contrast Detectability)
- Low Contrast - Contrast-to-noise ratio (CNR) (Catphan 600, 700)
- Slice Sensitivity Profile (SSP)
- Noise Power Spectrum (NPS), 2D and 3D NPS
- Phantoms: Catphan CTP700, CTP605, CTP604, CTP605, CTP600, CTP549(Catphan Lite), CTP504(Varian), CTP503 (Elekta), CTP500, CTP414, CTP410, CTP411, CTP549, ACR CT 464 Gammex, water/uniformity phantoms of all diameters
AutoSelection Screen - One image per Catphan Phantom module section - Catphan 600 CTP528 two images selected - Resolution gauge and bead image 10 mm off axis from resolution gauge.
Standard Processing Features
- Pixel Size – verifies the expected pixel size using the measured distance between four pins (3 air, 1 Teflon) in Catphan® sections CTP401 and CTP404. Measurement not supported by Catphan 700.
- CT Linearity (Sensitometry) – A least squares fit for the mean CT numbers and the attenuation coefficients is calculated for 20 energies (40-140 keV), the keV with the minimum variance is selected as the effective beam energy.
- Slice Thickness – The full-width at half-maximum (FWHM) of the CT number profile for each wire or bead ramp is measured. A trigonometric conversion is calculated based on the known ramp angle to yield the slice thickness.
- Patient Alignment System and Table Movement Accuracy – assessed from the slice thickness opposing wire angled ramps. The slice thickness test outputs the Table Position Offset; the z-axis offset.
- Spatial Resolution (MTF) – The modulation transfer function (MTF) is calculated from the discrete Fourier transform of the average vertical and horizontal LSF’s of the point spread function for a wire or bead impulse source. The program reports the 50%, 10% and 2% MTF values.
- Image Uniformity and Noise – Uniformity is calculated from regions of interest (ROI) positioned over a uniformity phantom section. Five ROI’s are defined: one at the phantom center and the other four along the axes at the same radius. Uniformity is the maximum absolute difference between the center and peripheral ROI means. Noise is calculated from one centered ROI, 40% of the phantom diameter, following the IEC guidelines for noise.
- Uniformity Index– Vertical and horizontal profiles 10 pixels wide are generated passing through the phantom’s center. The fractional uniformity of the profile is calculated as the percentage of the pixels within an acceptable range determined by the mean + 2 times the central noise or + 10H, whichever is smaller.
- Contrast Detail (Low Contrast Detectability) – The Contrast-Detail curve data is calculated using the measured noise sampled at the center of the low contrast module (CTP263 or CTP515).
- Low Contrast - CNR measurements for the low contrast supra-slice targets (5-15mm) in the CTP515 module
- SSP (Slice sensitivity profile) - FWHM processing of an impulse source (bead) in a series of sequential axial or helical images
Trend Analysis Reports
- Auto populates the hospital names and CT serial numbers
- Provides a thumbnail list of all the unique data sets based on the scan parameters used for easy selection
- User defined baseline values by either selecting the option for averaging the first 5, 10 or manually select data records or entering an arbitrary baseline
- User selects tolerances from a list of operators; + %, + , >, <, =
- Trend graphs provided of key fields
- Exportable reports to Microsoft’s Excel including trend graphs
Trend Analysis - Click icon on HTML report positioned next to each CT linearity sample.
Software Version Notes
126.96.36.199 (26 April 2023)
- ACR CT phantom Localizer/Table incrementation test will show a warning icon when the slice thickness is >2mm. Prior release pass/fail reported this as a failure.
- Catphan410 and 411 Slice 3 (low contrast) now reported as module CTP263, prior releases this module was reported as CTP468.
- Catphan410, 411 and 414 CTP445 module MTF bead size changed from 0.25mm to 0.28mm
- Catphan549 MTF module label changed from CT528 to CTP445, and the bead diameter has been changed from 0.25mm to 0.28mm
- Catphan500(legacy) phantom selection icon – added label ‘CTP528 1 MTF bead’. With this information the user will know if they have a legacy version or current Catphan500 model.
- CTP528 Module added search for two bead locations for batch mode processing
- CTP528 manual resolution gauge results are now reported in the HTML file for batch mode processing.
- Catphan605’s CTP682 module changed MTF wire diameter from 0.5mm to 0.05mm and switched MTF bead size labels between 0.18mm and 0.28mm.
- Catphan700 MTF bead size corrected for phantom orientation 9
- Catphan700 reference image for image 1 and image 3 locations corrected to match phantom orientation.
- DICOM(SCP) will display an error event in the task tray icon when the AE title is not correct.
- 3D NPS plot Y-axis label changed from freq. (HU^2mm^3) to NPS (HU^2mm^3).
- MTF analysis which does not report a 50% and 10% and 2% (all 3) measurement would generate a green Pass/Fail. This has been corrected to indicate this as a failure.
- Added Pass/Fail notification in the table of contents (HTML) for CTP591 slice thickness measurement
- Centered the radial array of ROI's used in the NPS analysis at the center of the phantom image and not the matrix center (255,255)
- MR ACR phantom low contrast auto detection was not working with some non-English number formatting. This has been corrected.
- Notification to the user about the availability of a new version of AutoQA Plus for download. Included are details about the new version and a URL link to download software.
- Maintenance expiration notification message provided in the task bar. Message is stopped after the message is clicked once.
- Manual MTF bead/wire selection UI screen has a new button that automatically finds the location of the highest pixel value in the image.
- Information added to the phantom orientation output section to indicate the phantom position, the distance the phantom is shifted left or right and above and below the center.
- Export/Import support that allows a user to exchange results between other users or to upload reports to a central user database
- Users can access trend analysis in the Report Archive screen. All trends are now available on one display screen with tab selection for individual trends.
- Table of contents included in the HTML report
- DICOM tags for Image Description, Series No., Acquisition No. and Instance No. added to all graphs and charts
- Noise Power Spectrum (NPS) processing (2D and 3D)
- New tab added to the Application Settings ‘Automations’ which generates an Excel file for each instance of processing to be stored in a folder defined by user on this Automations tab screen
- Images now included with HTML/PDF report for the C-D detectability measurement using module CTP468 or CTP263 for the Catphan410 phantom
- Optimized geometric distortion measurement threshold sampling for both image 1 and image 5 of the ACR MR phantom
- TE DICOM tag (0018,0081) parsing added when Echo Number(s) DICOM tag (0018,0086) is not found
- MR Report profiles updates with on/off controls for low contrast and high contrast manual selection screens
- Corrected Dutch regional settings/number formatting issues
- Corrected display scaling issues for CT and MR report profiles tabs
- Support added for reading long file names
- Folders with more than 5000 image files will no longer be sorted. Message displayed 5000 + more files found. User should change folder selected and select a subfolder or groups of subfolders. Restricting the number of files sorted avoiding crashing the application.
- MTF report profile using a '0%’ cutoff value which turns off a cutoff MTF measurement will not report a measurement.
- CTP504 and 604 default report profiled for the manual low contrast will output the CTP515 and CTP730 module image and adds the CNR measurement as a pass/fail test
- ACR CT phantom analysis supports patient orientation FFS (orientation 13)
- Export Multiple report profiles at the same time
- ACR CT phantom added to the list of phantoms supported
- The Series Select display grid now includes a thumbnail image for each image series displayed
- User can select multiple image folders at the same time at the DICOM folder selection screen
- MTF processing not supported when pixel size is <0.096mm (FOV<=50 and 512 matrix)
- CTP591 0.25mm bead ramp processing search area extended, and search threshold modified for image data with pixel size <0.2mm
- QA/Batch mode processing without a slice thickness image, the first image bin is skipped automatically, image placement starts at the second module bin
- Report Profile update now allows adding MTF filters with a new button ‘Save as New’. This allows user to edit existing MTF filter settings and save as new