ACMP 25th Annual Meeting

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1 Surveying and QC of Stereotactic Breast Biopsy Units for ACR Accreditation ACMP 25th Annual Meeting Seattle, WA May 3, 2008 Melissa C. Martin, M.S., FACR Therapy Physics, Inc. 879 West 190th St., Ste 419, Gardena, CA Office: Cell:

2 Learning Objective Become familiar with the recommendations and requirements of the ACR Stereotactic Breast Biopsy Accreditation Program (SBBAP) Quality Control Manual Information By product of conducting Quality Control tests for Stereotactic Breast Biopsy units is greater familiarity with the operation and performance of your SBB system, particularly image quality and the accuracy of needle placement during SBB.

4 LORAD Stereotactic Breast Biopsy System

5 LORAD Stereotactic Breast Biopsy System

6 LORAD Stereotactic Breast Biopsy System Control Pendant

7 Cartesian coordinate system Geometry is reset for each patient x x z Don Jacobson 2/07 y

8 Siemens (Fischer) MammoVision Biopsy System

9 Siemens (Fischer) MammoVision Biopsy System

10 Fixed relationship between Autoguide and breast support Spherical coordinate system Distance Vertical angle Horizontal angle Don Jacobson 2/07

11 Don Jacobson 2/07

13 Don Jacobson 2/07

14 Goals of QC for Stereotactic Breast Biopsy To ensure that image quality in Stereotactic Breast Biopsy equals or exceeds that of screening and diagnostic mammography To ensure that equipment designed specifically for Stereo Breast Biopsy performs properly To ensure that needle localizations are accurate

15 General Requirements for SBBAP Qualified TEAM: Physicians, Technologist, and Medical Physicist Equipment: Table or add-on ;; film or digital QA Program, Manual, and Committee Technologist s s QC Testing - daily, weekly, monthly, semi-annual - 6 tests Medical Physicist s s QC Testing - acceptance and annual - 11 tests

16 The Quality Assurance Team: Physician QC Technologist Medical Physicist

17 Medical Physicist s s Qualifications for SBBAP: Initial Certification by ABR, ABMP in Diagnostic Medical Physics OR Alternate Education, Training and Experience AND >6/1/97: Have Performed 1 SBB Survey Under the Guidance of a Medical Physicist Qualified to Perform SBB Surveys <6/1/97: Have Performed 3 SBB Surveys

18 Medical Physicist Qualifications for SBBAP: Re-Accreditation After 3 Years At Least 1 SBB Physics Survey Per Year At Least 3 Hours of Continuing Education in SBB Physics Documentation of Above

19 Quality Control: Medical Physicist s s Evaluation Acceptance Test Before Patient Use Annually Thereafter Report Required as Part of ACR Application

20 Quality Control: Medical Physicist s s Evaluation The 1999 ACR SBB Quality Control Manual has a section for the Medical Physicist It has suggested Test Procedures, Forms, and Summary Report Format Detailed instructions on 11 Required Physicist s s tests

21 ACR Quality Control Manuals Mammography QC Manual (1990, 1992, 1994, 1999) Barium Enema QC Manual (1998) Stereotactic Breast Biopsy QC Manual (1999) MRI QC Manual (2001) Sent free to all facilities in program To purchase, call ACR Pubs: (800) QC forms available to anyone on Web site

22 Rad Tech QC Tests Mammo QC Tests Also Apply if Screen-Film Used Localization Accuracy - daily Phantom Image - weekly Hardcopy Output Quality - monthly, if app Visual Checklist - monthly Compression Force - semi-annually Repeat Analysis - semi-annually Zero Alignment Test before ea patient, if app

23 Medical Physicist s s Quality Control Tests 1. Stereotactic Unit Assembly Evaluation 2. Collimation Assessment 3. Focal Spot Performance & Digital System Limiting Resolution 4. kvp Accuracy and Reproducibility 5. Beam Quality Assessment (HVL) 6. AEC or Manual Exposure Performance

24 Medical Physicist s s Quality Control Tests 7A. Uniformity of Screen Speed 7B. Digital Receptor Uniformity 8. Breast Entrance Exposure, Average Glandular Dose, and Exposure Reproducibility 9. Image Quality Evaluation 10. Artifact Evaluation 11. Localization Accuracy Test

25 Stereotactic Unit Assembly Evaluation

26 Collimation Assessment

27 Collimation Assessment

28 Collimation Assessment

29 Collimation Assessment SID = 84 cm

30 Digital Limiting Resolution/Focal Spot

31 Digital Limiting Resolution/Focal Spot

32 Digital Limiting Resolution/Focal Spot

33 kvp Accuracy and Reproducibility

34 kvp Accuracy and Reproducibility

35 Beam Quality Assessment

36 Beam Quality Specifications for SBB Units The minimum acceptable Half-Value Layer measurement on a digital or film/screen SBB unit is Action Limit: If measured HVL < (kvp/100) (in mm Al) or if measured HVL > (kvp/100) + C (in mm Al) where C = 0.12 for Mo/Mo, C = 0.19 for Mo/Rh, and C = 0.22 for Rh/Rh, then seek service correction.

37 Image Quality Evaluation (Phantom) Objective: Ensure Image Quality for SBB meets or exceeds that of mammography, and to detect temporal changes in image quality Procedure: Same as for Mammography, except ACR phantom must be imaged in 4 separate quadrants for digital because of small field of view

38 Two Types of Approved Phantoms Mini Stereotactic Breast Biopsy Accreditation Phantom Nuclear Associates Mammography Accreditation Phantom RMI 156 Nuclear Associates

39 Mini Stereotactic Breast Biopsy Accreditation Phantom Chest Wall Side

40 SBBAP Testing Criteria Dose and Phantom Dose - Must be less than 300 mrads (3 mgy) Phantom image quality Fibers Speck Groups Masses MAP Phantom F/S Digital Mini Phantom F/S Digital

41 Image Quality for SBB Units RMI 156 or NA MAP Phantom

42 on Jacobson 2/07 NA Mini- Phantom

43 RMI 156 Accreditation Phantom

44 Nuclear Associates Digital Mini Phantom

45 AEC or Manual Exposure Performance 2 cm Thickness

46 AEC or Manual Exposure Performance 4 cm Thickness - Also used for Uniformity and Artifacts

47 AEC or Manual Exposure Performance 6 cm Thickness 8 cm Thickness

48 AEC or Manual Exposure Performance

49 n AEC or Manual Exposure Control a l Performance Requirement e Action Limit (Digital): x c If the signal range e exceeds ±20% of signal for 4 cm phantom, e d s revise technique chart. s i g r a n g e ± 2 0 % Action Limit (Screen-Film): If the density o f range exceeds ±0.15 of mean, revise technique chart. s i g n a l f o r 4 c m

50 Digital Receptor Uniformity Requirements Digital Receptor Uniformity Requirements For Units with ROI statistics measurement For Units with ROI statistics measurement capability: capability: Action Limit: If SNR(I) / Action Limit: If SNR(I) / SNR(Center SNR(Center) is > 1.15 ) is > 1.15 or < 0.85, seek service correction. or < 0.85, seek service correction. I f m e a s u r e d H V L < ( k V p / ) ( i n m m A l ) I f m e a s u r e d H V L < ( k V p / ) ( i n m m A l )

51 Digital Receptor Uniformity Requirements Digital Receptor Uniformity Requirements For Units without ROI statistics For Units without ROI statistics measurement capability: measurement capability: I f m e a s u r e d H V L < ( k V p / ) ( i n m m A l ) I f m e a s u r e d H V L < ( k V p / ) ( i n m m A l ) If line w/o black dots > 1/4 length of image, seek service correction If non-uniform areas (w/o black dots) > 10% of image or Action Limits: If geometric pincushioning > 1 cm from edge of image or

52 Digital Receptor Uniformity

53 Digital Receptor Uniformity - Image Statistics

54 Breast Entrance Exposure, Average Glandular Dose, and Exposure Reproducibility Same Procedure as for Mammography Recommended Signal Level for Digital Digital Matrix Sizes Performance Criteria: a) Coefficient of Variation < 0.05 b) Av. Glandular Dose < 3 mgy for Screen/Film and for Digital Image Receptors

55 Entrance Exposure/Mid-Glandular Doses

56 Entrance Exposure/Mid-Glandular Doses

57 Entrance Exposure/Mid-Glandular Doses

58 Artifact Evaluation

59 11. Localization Accuracy: Gelatin Phantom Objective: To assure that the biopsy needle is accurately placed for sampling as directed from the stereotactic scout images Technologist to perform test Physicist to observe and analyze results End-to to-end test which supplements the daily in-air positioning accuracy test

60 Localization Accuracy: Gelatin Phantom Method 1. Position Needle: - Target Lesion Using Stereo Views - Position Core Needle to Proper X, Y, and Z Coordinates 2. Verify Needle Position: - Acquire Stereo Pre-fire Images - Needle Tip should be within Lesion 3. Fire Gun

61 Localization Accuracy: Method Gelatin Phantom 4. Verify Post-Fire Position - Acquire Post-Fire Stereo Images - Needle Tip should be beyond Center of Lesion 5. Verify Sampling of Lesion - Examine Contents of Core Sample

62 Gelatin Phantom Biopsy

63 Gelatin Biopsy Images

64 Localization Accuracy

67 SAMS Questions

68 0% 0% 0% The maximum allowable patient mid-glandular dose for a 4.5 cm breast equivalent phantom under MQSA is 1. 1 mgy 2. 2 mgy 3. 3 mgy 0% 0% 4. 5 mgy mgy 10

69 Answer: C - 3 mgy Ref: Stereotactic Breast Biopsy Accreditation Manual American College of Radiology (1997)

70 Using the dedicated mini-phantom designed for SBB units, the minimum acceptable phantom image quality scores on a unit with digital imaging are: 0% 0% 0% 1. 2 fibers, 3 speck groups, 2.5 masses 2. 3 fibers, 3 speck groups, 2.5 masses 3. 4 fibers, 3 speck groups, 3.0 masses 0% 0% 4. 3 fibers, 2.5 speck groups, 2.5 masses 5. 3 fibers, 4 speck groups, 3.0 masses 10

71 Answer: b - 3 fibers, 3 speck groups, 2.5 masses Ref: Stereotactic Breast Biopsy Accreditation Manual American College of Radiology (1997)

72 The minimum acceptable Half Value Layer measurement on a digital SBB unit at 28 kvp is 0% 0% 0% 0% 0% mm Al mm Al mm Al mm Al mm Al 10

73 Answer: e mm Al Ref: Stereotactic Breast Biopsy Accreditation Manual American College of Radiology (1997) Min. HVL = (kvp/100) mm Al

74 The minimal acceptable uniformity level for a digital receptor on a SBB unit is 0% 0% 0% 0% 0%

75 Answer: d Ref: Stereotactic Breast Biopsy Accreditation Manual American College of Radiology (1997) Action Limit: If SNR(I) / SNR(Center) ) is > 1.15 or < 0.85, seek service correction.

76 The AEC or Manual Exposure Control Performance requirement on a SBB unit with digital imaging is 0% 0% 0% 0% 0% 1. +/ of the average signal for thickness of cm 2. +/ of the average signal for 4 cm phantom 3. +/ of the average signal for thicknesses of cm 4. +/ of the average signal for 4 cm phantom 5. +/ of the average signal for thicknesses of cm 10

77 Answer: d: +/- 20% of average signal for 4 cm phantom Ref: Stereotactic Breast Biopsy Accreditation Manual American College of Radiology (1997)

Unique Features of the GE Senoclaire Tomosynthesis System. Tyler Fisher, M.S., DABR Therapy Physics, Inc.

Unique Features of the GE Senoclaire Tomosynthesis System Tyler Fisher, M.S., DABR Therapy Physics, Inc. Conflict of Interest Disclosure I have no conflicts to disclose. Learning Objectives Overview of