Resident Physics Series ACR Mammography Protocols Mammography Quality

Resident Physics Series ACR Mammography Protocols

Mammography Quality Standards Act (MQSA) 1992 “to ensure the safety and reliability of mammography and help detect breast cancer in its earliest, most treatable stages” Mammography practice under federal control (FDA)

MQSA Requirements Yearly physics surveys Yearly FDA inspections Georgia x-ray regulators on contract with FDA FY 2013 No violations: 87%

Facility Accreditation by “Accrediting Body” American College of Radiology (ACR) State of Arkansas State of Iowa State of Texas

FDA Facility & Procedure Count June, 2006 Late 2013 % Change Total certified facilities 8850 8691 -1. 8 Total accredited units 13588 1027 12195 8004 -10. 3 +679. 4 1455 12195 +738. 1 33, 940, 037 38, 596, 266 +13. 7 Certified facilities with FFDM units Accredited FFDM units Annual mammography procedures

1 -Jan 6 -Jan 11 -Jan 16 -Jan 21 -Jan 26 -Jan 31 -Jan 5 -Feb 10 -Feb 15 -Feb 20 -Feb 25 -Feb 1 -Mar 6 -Mar 11 -Mar 16 -Mar 21 -Mar 26 -Mar 31 -Mar 5 -Apr 10 -Apr 15 -Apr 20 -Apr 25 -Apr 30 -Apr Number of Accredited FFDM Units # FFDM 14000 12000 10000 8000 6000 4000 2000 0 Nov 03 Dec 13

Number of Accredited Units # Mammo Units 16000 14000 12000 10000 8000 6000 4000 2000 1 6 11 16 21 26 31 36 41 46 51 56 61 66 71 76 81 86 91 96 101 106 111 116 121 0 Nov 03 Nov 13

% FFDM Units 100 90 80 70 60 50 40 30 20 10 0 Dec 2003 June 2015

Mammography QC Manual Revised Edition, 1999 Sections Radiologist Clinical Image Quality Radiologic Technologist Medical Physicist

Quality Assurance (QA) QA should ensure Every imaging procedure is necessary & appropriate to clinical problem at hand images contain information critical to solution of that problem

Quality Assurance (QA) recorded information is correctly interpreted made available to patient’s physician in a timely fashion consistent with image quality objectives, examination results in lowest possible radiation exposure cost inconvenience to the patient

Quality Control (QC) QC is integral part of QA Acceptance Testing detection of defects in equipment that is newly installed or has undergone major repair Baselines Establishment of baseline equipment performance quantitative data when system operating properly

Quality Control (QC) Diagnosis of changes in equipment performance before they become radiologically apparent Verification of correction of causes of deterioration in equipment performance

Facility Responsibility Designate One Lead Interpreting Physician

Lead Physician’s Responsibilities Ensure technologists have adequate orientation based on procedure manual training continuing education Ensure effective QC program

Radiologist’s Responsibilities Designate one technologist responsible for QC QC tech can delegate responsibilities

Radiologist’s Responsibilities Ensure availability of appropriate test equipment Arrange staffing / scheduling to allow time for QC

Radiologist’s Responsibilities provide frequent consistent positive & negative feedback to technologists about film quality & QC Review technologist’s test results no less than every 3 months more often if inconsistent results

Radiologist’s Responsibilities Select a medical physicist administers QC program performs physicist’s tests Review physicist’s test results

Radiologist’s Responsibilities Oversee or designate qualified individual to oversee radiation protection program for employees patients individuals in surrounding area

Radiologist’s Responsibilities Ensure proper maintenance of records in QC procedures manual employee qualifications mammography technique / procedures quality control / safety / protection infection control

Radiologist’s Responsibilities “The radiologist is ultimately responsible for the quality of films produced under his or her direction and bears ultimate responsibility for both proper QC testing and QA procedures in mammography. ”

Physicists & Digital Mammoraphy Physicist must insure equipment meets manufacturer’s specifications Equipment specs now defined by manufacturer, not ACR/FDA

Physicist’s Responsibilities Note: All physicist’s tests are to be done annually or after tube replacement or major service

Physicist’s Responsibilities: Mammography Unit Assembly Evaluation mechanical stability / identification of sharp edges receptor stability locks / motions / detents operator shielding thickness scale accuracy indicator lights working technique chart posted (see next slide)

Technique Chart Even though most mammo is phototimed, still need technique chart For given breast size, density, view specify machine set-up Phototimer mode (auto standard, contrast, dose, …) Density (-2, -1, 0, …)

Technique Chart Wrong (my opinion) Display k. Vp, m. As, target, filter calculated by machine for given image Correct (my opinion) Display machine settings selectable by technologist for this breast and view Should provide enough guidance to allow a technologist who has not worked in this room or facility to properly set up a study

Physicist’s Responsibilities: Mammography Unit Assembly Evaluation lm Fi holder. C R Cassettes slide smoothly into/out of Override available for auto-decompression display must indicate when auto-decompression turned off Manual release of compression if power lost

Collimation Assessment x-ray light field alignment beam does not exceed receptor by > 2% SID compression paddle / receptor alignment at chest wall within 1% SID paddle not visible on image Image should fill film F i l m Many units by design will not do this

Physicist’s Responsibilities Focal Spot Performance limiting resolution pattern k. Vp accuracy / reproducibility Beam quality (HVL) minimum & maximum minimum: patient dose maximum: image contrast

Automatic Exposure Control (AEC / Phototiming) k. Vp tracking Thickness tracking image mode tracking (cassette sizes, w w/o grid) automatic mode tracking unit selects k. Vp, target, filter density control even steps of ~ 15 -20%

Physicist’s Responsibilities: Screen Uniformity F i l m compare O. D. of each cassette using phototimer AEC Reproducibility

Physicist’s Responsibilities Breast Entrance Exposure, Average Glandular Dose, RMI-156 “accreditation” phantom used for entrance exposure / average glandular dose

Breast Average Glandular Dose Limits 0. 3 rad (300 mrads, 3 m. Gy) maximum per view for screen-film receptors using a grid Same for film and digital 0. 1 rad (100 mrads, 1 m. Gy) maximum per view for nongrid screen-film receptors Radiation output rate > 800 m. R/sec

Image Quality Evaluation use RMI-156 “accreditation” phantom record fibers speck groups masses optical densities technique

A Poor Phantom Image

Artifact Identification Artifact evaluation / description Done with phantom

Physicist’s Responsibilities Viewing conditions ambient light viewbox brightness l m Fi My experience Ambient lighting often ignored

Technologist’s Responsibilities All QC must not only be performed but must be documented! Daily darkroom cleanliness processor quality control sensitometric data Weekly lm i F screen cleanliness viewboxes and viewing conditions Phantom images Fi lm

Technologist’s Responsibilities Monthly: Visual Checklist visual checklist SID indicator angle indicator locks field light smooth motions

Technologist’s Responsibilities Monthly: Visual Checklist cassette lock Is cassette held firmed in place when tubestand tilted Compression device & firm compression Smooth edges Holds pressure hand switch placement visibility switches/ lights/ meters cones/ collimators

Technologist’s Responsibilities Quarterly Repeat analysis breakdown by cause motion positioning technique static etc.

Semi-Annual Technologist’s Responsibilities Compression can use bathroom scale covered with towel 25 - 40 pounds for automatic systems at least 25 pounds for manual compression

The End Questions?