AAPM TG-270 display acceptance test: practical steps
Set up and document a medical display acceptance test using the display category, viewing conditions, measurements, and a facility-approved QA plan.
An AAPM TG-270 display acceptance test establishes a baseline for a medical display before routine use. Identify its intended role, test it in the actual viewing environment, record the measurements and visual checks, then compare them with the facility’s approved criteria. AAPM Report 270 is the primary source for display QA recommendations.
PerfectLum can help run and document checks, but the software result is not a blanket declaration of clinical suitability. The medical physicist or display QA lead should select the appropriate category and review failures. For the grayscale target itself, see DICOM Part 14’s scope; for the product workflow, see PerfectLum.
Guidelines for Performing an Acceptance Test for AAPM TG 270 Using Qubyx PerfectLum
1. Introduction
AAPM Report 270 updates display QA guidance from the earlier AAPM TG-18 report. With the shift from CRT displays to modern flat-panel technology, TG 270 incorporates updated definitions of display types, revised test patterns, and performance standards that are tailored to contemporary medical imaging environments. It provides a framework for checking flat-panel displays used in medical imaging.
2. Understanding AAPM TG 270
What is AAPM TG 270?
- Purpose: TG 270 updates the guidelines from TG 18, reflecting the advancements in display technology.
- Updates Include:
- New Display Definitions: Clear distinctions of display types used in various clinical settings.
- Updated Testing Patterns: Optimized for the nuances of flat-panel displays.
Revised Performance Standards: Ensuring that displays used for image acquisition and review adhere to rigorous quality benchmarks.
3. Display Categories
AAPM TG 270 classifies displays into four distinct categories, each with its own performance criteria:
- Diagnostic Displays: Designed for high-resolution tasks and detailed image analysis, these displays require the most stringent quality controls.
- Modality Displays: Integral to imaging devices, these screens must accurately represent images in real time.
- Clinical Specialist Displays: Tailored for specialists, these displays support focused diagnostic observations with specific performance metrics.
Electronic Health Record (EHR) Displays: Optimized for reviewing patient records and ancillary data, these displays balance clarity with ease of use.
4. How to Perform the AAPM TG 270 Acceptance Test Using Qubyx PerfectLum
The simplest and most efficient way to perform an acceptance test is by using Qubyx PerfectLum. Follow the steps below:
4.1. Preparation
- Verify Your Setup: Ensure that the display is properly connected and has undergone a baseline calibration.
- System Readiness: Confirm that your workstation meets all hardware and software prerequisites for running Qubyx PerfectLum.
4.2. Initiating the Test
- Launch the Application: Open Qubyx PerfectLum on your system.
- Access the Quality Assurance Tab: Navigate to the “Quality Assurance” tab within the application interface.
- Select the Regulation and Display Category:
- Choose the AAPM TG 270 regulation.
- Select the appropriate display category (Diagnostic, Modality, Clinical Specialist, or EHR).
- Enter Workstation Details: Fill in the required information regarding the workstation location.
- Connect Your Measurement Device: Attach your measurement device, such as the Qubyx X1, to ensure precise readings during the test.
4.3. Executing the Acceptance Test
- Start the Test: Click the “Perform Acceptance Test” button.
- Provide Tester Information:
- Enter the tester’s name.
- Record the ambient light conditions, as these can affect measurement outcomes.
- Follow the Wizard: The system will guide you through a series of visual tests. Answer all questions prompted by the wizard to complete the test process.
4.4. Review and Reporting
- Monitor Results: The integrated dashboard displays test outcomes in real time, allowing for convenient evaluation.
- Generate Reports: Export test results in PDF or Excel format for documentation and further analysis.
By following these comprehensive guidelines, you can easily perform an AAPM TG 270 acceptance test using Qubyx PerfectLum. The recorded results help the facility assess the display against its chosen criteria and document any corrective action.
For any technical questions or further assistance, please refer to the official TG 270 documentation or contact our support team.
| Schedules | |||||
|---|---|---|---|---|---|
| Diagnostic Mammography | Diagnostic | Modality | Clinical Specialist | Electronic Health Record | |
| Acceptance test measurement | |||||
| Quantitative Min/Max Luminance | Yes | Yes | Yes | Yes | Yes |
| Quantitative Luminance Response | Yes | Yes | Yes | Yes | Yes |
| Quantitative Color Assessment | Yes | Yes | Yes | Yes | Yes |
| Quantitative Ambient Luminance / Illuminance | Yes | Yes | Yes | Yes | Yes |
| Quantitative Uniformity | Yes | Yes | Yes | Yes | Yes |
| Acceptance Test visual | |||||
| Qualitative Luminance response | Yes | Yes | Yes | Yes | Yes |
| Qualitative Ambient Luminance/Illuminance | Yes | Yes | Yes | Yes | Yes |
| Qualitative Spatial Resolution | Yes | Yes | Yes | Yes | Yes |
| Qualitative Uniformity | Yes | Yes | Yes | Yes | Yes |
| Diagnostic Mammography | Diagnostic | Modality | Clinical Specialist | Electronic Health Record | |
| Consistency test measurement | |||||
|
Quantitative Min/Max |
Annually | Annually | Annually | Annually | Annually |
| Luminance | |||||
| Quantitative Luminance Response | Annually | Annually | Annually | No | No |
| Quantitative Color Assessment | Annually | Annually | Annually | No | No |
| Quantitative Ambient Luminance / Illuminance | Annually | Annually | No | No | No |
| Quantitative Uniformity | No | No | No | No | No |
|
Consistency Test visual |
Consistency Test visual | ||||
| Qualitative Luminance response | Quarterly | Quarterly | Quarterly | Annually | Annually |
| Qualitative Ambient Luminance/Illuminance | Quarterly | Quarterly | Annually | Annually | Annually |
| Qualitative Spatial Resolution | Quarterly | Quarterly | Annually | Annually | Annually |
| Qualitative Uniformity | Quarterly | Quarterly | Annually | Annually | Annually |
Reviewing category-specific thresholds
The tables below summarize suggested levels and checks from the 2019 AAPM TG-270 report (Tables VI and VII). Criteria depend on the display category and viewing conditions; a qualified reviewer must evaluate the combined measurements and select the facility’s acceptance plan. Verify these values against the primary report before clinical use.
| Thresholds | |||||
|---|---|---|---|---|---|
| Diagnostic Mammography | Diagnostic | Modality | Clinical Specialist | Electronic Health Record | |
| Test measurement | |||||
| Quantitative Min/Max Luminance | LR target 350 (acceptable 250–450) L’min ≥ 1.2 cd/m2 L’max target 420 cd/m2 (acceptable ≥ 350 cd/m2). Note: L’max = Lmax + Lamb. L’min = Lmin + Lamb. LR= L’max/L’min | LR target 350 (acceptable 250–450) L’min ≥ 1.0 cd/m2 L’max target 350 cd/m2 (acceptable ≥ 300 cd/m2). | LR target 350 (acceptable 250–450) L’min ≥ 0.8 cd/m2 L’max target 250 cd/m2 (acceptable ≥ 200 cd/m2). | LR target 350 (acceptable 250–450) L’min ≥ 0.8 cd/m2 L’max target 250 cd/m2 (acceptable ≥ 200 cd/m2). | LR target 350 (acceptable 250–450) L’min ≥ 0.8 cd/m2 L’max target 250 cd/m2 (acceptable ≥ 200 cd/m2). |
| Quantitative Luminance Response | DICOM GSDF deviation 10% | DICOM GSDF deviation 10% | DICOM GSDF deviation 20% | DICOM GSDF deviation 20% | DICOM GSDF deviation 20% |
| Quantitative Color Assessment | ΔD65 (u’ , v’) < 0.01 | ΔD65 (u’ , v’) < 0.01 | ΔD65 (u’ , v’) < 0.02 | ΔD65 (u’ , v’) < 0.02 | ΔD65 (u’ , v’) < 0.02 |
| Quantitative Ambient Luminance / Illuminance | AR = Lamb/Lmin < 1/4 | AR = Lamb/Lmin < 1/4 | AR = Lamb/Lmin < 1/4 | AR = Lamb/Lmin < 1/4 | AR = Lamb/Lmin < 1/4 |
| Quantitative Uniformity | LUDM < 30% | LUDM < 30% | LUDM < 30% | LUDM < 30% | LUDM < 30% |
| Test visual | |||||
| Qualitative Luminance response | “Are all low contrast features, within ±5% contrast, visible under typical ambient conditions?” | idem | idem | idem | idem |
| Qualitative Ambient Luminance/Illuminance | “Are the low-contrast features visible in the darkest areas of the test image under normal ambient light and with nearly dark conditions?” | idem | idem | idem | idem |
| Qualitative Spatial Resolution | -“Does the graphics card to display pixel mapping correspond one-to-one (is the graphics card resolution identical to the native resolution of the display)?” | idem | idem | idem | idem |
| Qualitative Uniformity | “There are no visible non-uniformities that would impact the clinical use of the display.” | idem | idem | idem | idem |
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