Practical Aspects of Medical Physics Surveys of Mammography Equipment and Facilities

Transcription

1 Practical Aspects of Medical Physics Surveys of Mammography Equipment and Facilities Melissa Martin, M.S., FAAPM, FACR, FACMP AAPM Annual Meeting - Philadelphia July 19, 2010 MO-B-204C-1

2 Educational Objectives To cover the annual tests to be performed by the medical physicist for both film/screen and digital mammography units To discuss efficient methods of performing these required tests To discuss the required tests for laser printers and monitors or processors and view boxes

3 Film/Screen MQSA Required Tests Follow the tests outlined in the ACR 1999 QC Manual for Film/Screen Mammography Physicists must use the Summary Forms from the ACR Website: Download forms for both Equipment Evaluations and Annual Surveys

4 FILM/SCREEN Summary Sheet

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6 FFDM Equipment Evaluations and Surveys At the present time, the FDA requires the physicist to use the FFDM Manufacturer s QC Manual and Procedures. Physicist must download the Summary Forms for both Equipment Evaluations and Annual Surveys from the ACR website for the particular manufacturer s unit tested.

7 FFDM Equipment Evaluations and Surveys Physicist must follow the latest version of the Manufacturers QC Manual procedures for the unit tested (may not be the latest version available from that particular manufacturer if the unit has not had the latest upgrade/update installed) Test results must meet manufacturer s performance standards

8 FFDM Equipment Evaluations and Surveys Failures must be fixed before use on patients or within 30 days as specified for each particular test GE, Fuji, Hologic and Siemens have received FDA Approval for alternative standards for some QC test results to allow 30 days to achieve compliance with manufacturer s specifications

9 same as FDA s ACR s Current FFDM QC Requirements ACR suggests using Manufacturer s data forms Medical Physicists MUST complete the ACR s Summary Forms If the medical physicist passes a test, ACR accepts it. If the medical physicist fails a test, ACR requires corrective action documentation. If the medical physicist says NA or see comments, the ACR requests further clarification.

10 Lorad Selenia

11 LORAD Selenia QC Tests QC Manual tests: Medical Physicist Annually Radiologic Technologist Daily Weekly Biweekly Monthly Quarterly Semiannually

12 Medical Physics Annual Tests Mammographic Unit Assembly Evaluation Collimation Assessment Artifact Evaluation kvp Accuracy and Reproducibility HVL Measurement Evaluation of System Resolution Breast Entrance Exposure and Glandular Average Dose Radiation Output Rate Phantom Image Quality Evaluation Signal-To-Noise and Contrast-To-Noise Measurements Viewbox Luminance and Room Illuminance Softcopy Workstation QC

13 ACR Required Tests The ACR does require specific tests, common to all vendors: Weekly: Viewboxes and Viewing Conditions Monthly: Visual Checklist Semi-Annual: Compression force Taken from the ACR Mammography Quality Control Manual

14 Daily and Weekly QC Tests (per Vendor) Test GE Fuji CR Siemens Hologic Fischer Monitor Cleaning Daily Laser Image Quality Test Weekly Daily Flat Field Calibration Weekly Weekly Weekly Weekly Artifact Evaluation Weekly Weekly Phantom Image Quality Weekly Weekly Daily Weekly Weekly Phantom Acquisition Test Signal-to-noise-ratio Weekly Weekly Weekly Contrast-to-noise ratio Weekly Weekly Weekly Weekly Viewbox and Viewing Conditions Weekly Weekly Compression Thickness Indicator Test Bi-weekly 14

15 Monthly and Quarterly QC Tests Test GE Fuji CR Siemens Hologic Fischer MTF Measurement DS/Essential weekly 2000D - monthly AOP Mode and SNR Monthly SNR Weekly SNR Weekly System Resolution System Operation Monthly Monthly Visual Checklist Monthly Monthly Monthly Repeat Analysis Quarterly Quarterly Quarterly Quarterly Quarterly Compression Force Soft Copy Workstation QC Laser Film Printer QC Semi-annually FDA guidance Per printer mfg Semiannually Semi-annually Semi-annually FDA guidance FDA guidance FDA guidance FDA guidance Per printer mfg Daily Weekly Mobile Unit QC At every move Unknown At every move At every move Image Plate Fog Semiannually Semiannually At every move 15

16 Laser Printer - must be able to print images on mammography laser film

17 Laser Printer Quality Control SMPTE Pattern from Acquisition Workstation Measure 10%, 40% and 90% Density Patches Daily Performance 40% density tracks within ±15% (40% - 10%) density tracks within ±15% 90% density tracks within ±15% NOTE: Printer uses linear LUT

18 OD Requirements for Hi-Resolution Laser Imagers D max > 3.5 OD Mid-density > 1.5 OD

19 Laser Processor QC Kodak daily sensitometry Base + Fog Density Difference OD closest to 2.20 minus OD closest but not less than 0.45 Mid-density step closest to but not less than 1.20 Action Limits: D max MD & DD OD B+Fog = 0.03 D max

20 FDA Required Laser Printer QC GE 2000D & Senographe DS: Follow the laser printer manufacturer s QC manual Fischer Senoscan: Follow the laser printer manufacturer s QC manual Lorad Selenia: Follow the Lorad Selenia QC Manual Siemens Mammomat Novation DR: Follow the laser printer manufacturer s QC manual but conduct QC every day that images are printed. Fuji MammoCR System: Follow the laser printer manufacturer s QC manual

21 Viewing Conditions for Monitors From the ACR QC Manual, 1999, the room illuminance must be below 50 lux. From the February 2006 version of the Medical Physicist Equipment Evaluation forms from ACR, room illuminance for soft copy displays must be below 20 lux.

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23 Hologic QC tests on SecurView Required testing is determined by monitor type CRT LCD (Flat panel) CRT Manually perform QC tests using photometer on each monitor to document the testing LCD QC tests are set up to run automatically at night Technologist must check results and record 23

24 Hologic QC tests on SecurView CRT: Cathode Ray Tube Weekly Calibration Settings Check Measure Display White Measure Display Black Monthly Measure Display Black Measure Display White Quarterly Uniformity Measurement LCD: Liquid Crystal Display Weekly Automatic I-Guard Check Calibration Settings Check Measure Display White Monthly Measure Quality Level 24

25 Softcopy Workstation QC 25

26 13. Diagnostic Review Workstation QC Date: Review Station Model: 18-May-10 SVDX Review Station SN: Left Monitor Right Monitor Comments Monitor Serial Number Barco 5K Monitors White Level Performance Target = 600 cd/sq m Black Level Performance NA - LCD Monitors NA - LCD Monitors Quality Level Performance OK OK Within 3% of 100% target Uniformity Performance NA - LCD Monitors NA - LCD Monitors Action Limit: The white level shall not be different from the monitor calibration level by more than 6%. The quality level performance shall not exceed 10%.

27 Phantom Image - Hologic Selenia FFDM Units Review Weekly Phantom Image Results Measured film densities Phantom objects seen (printer, monitors) 5 fibers 4 speck groups 4 masses

28 SNR and CNR Measurements ACR Accreditation Phantom with Disc (Weekly) Measure SNR and CNR from Image Selenia FFDM Units

29 SNR and CNR Measurements Passing Criteria - Selenia FFDM Units SNR at least equal or greater than 40 CNR should stay within ±15% of measurement obtained during acceptance testing of system

30 GE Senographe FFDM Units

31 QC Manuals for GE Senographe FFDM Units

32 GE Display Systems

33 CNR Test for Senographe 2000D

34 MTF Measurement D

35 Artifacts Physicist must test all Target/Filter combinations and both sizes of focal spots for artifacts

36 GE Senographe Essential Large and Small Fields Require Collimation Assessment of all three positions of small field plus large field for both target materials

37 GE Senographe Essential Control Panel Laterality must be selected prior to each exposure

38 GE Senographe Essential Measure Entrance Skin Exposure with Ion Chamber at 5 cm from outside edge of detector area.

39 Senographe DS & Essential

40 Seno DS & Essential - IQST Phantom

41 GE Senographe DS & QA Phantom Overview Essential Uniform area for noise power spectrum measurement Step wedge for contrast measurement Mesh for resolution uniformity measurement Edge object for MTF measurement Rulers for measuring distance of detector from chest wall edge of Bucky Tabs to position IQST with respect to chest wall edge of image receptor. Rails to position the IQST left-to-right

42 AOP Mode and SNR Check

43 AOP Test Materials

44 AOP Phantom Techniques

45 AOP Expected Parameters

46 CR Plates Fuji CRm System CR Plate Reader

47 Fuji CRm System S-Value Confirmation Measure Exposure Rate at Surface of Breast Support

48 Dynamic Range Test Fuji CRm System

49 Fuji CRm System - CNR Test CNR PER OBJECT THICKNESS Image Mode: Auto Time Focal Spot: 3 Density Control: 0 AEC Mode: Auto Time Phantom Thickness Target Filter kvp mas (Auto) mas (Manual) CNR CNR (relative to 4cm PMMA) Acceptable level 2 cm Mo Mo % >110% 4 cm Mo Mo % 100% 6 cm Mo Rh % >90% PASS

50 Inter Plate Consistency Exposure Unite ID: Lorad M-III Exposure conditions AECmode Tar get Filter kvp Auto Time Mo Mo 25 Group: Small Cassettes mas limit is plus or minus 10 % from mean. SNR limit is plus or minus 15 % from mean. Cassette ID ma s Accept able A456, #3 132 Yes A234, #2 132 Yes A123, #1 132 Yes A222, #4 132 Yes A111, #5 132 Yes SN R Accept able Yes Yes Yes Yes Yes A777, #6 133 Yes Yes

51 Fuji CRm - Monitor Tests Site: Med. Img Ctr of So Cal Date of Survey: 4/19/2007 Room #: Reading Room Date of Installation: Apr-07 DOME E5 Left Monitor Right Monitor Serial Numbers 703PNKN PNKN00028 Luminance Value Setting (cd/sq-m) Target Value = 500 cd/sq-m Is the CXtra icon present in the taskbar and shown as a green check mark? Manual Conformance report for both displays attached? Is DICOM calibration Graph for both displays attached? Yes Yes Yes No No No

52 Thank You!!! Melissa C. Martin, M.S., FACR Therapy Physics Inc. 879 West 190 St., Ste 419 Gardena, CA Office Phone: