Magnetic Resonance Imaging
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2015 Magnetic Resonance Imaging QUALITY CONTROL MANUAL Radiologist’s Section MRI Technologist’s Section Medical Physicist/MRI Scientist’s Section 2015 Magnetic Resonance Imaging QUALITY CONTROL MANUAL Radiologist’s Section MRI Technologist’s Section Medical Physicist/MRI Scientist’s Section American College of Radiology Committee on Quality Assurance in Magnetic Resonance Imaging Ron Price, PhD, FACR, chairman Jerry Allison, PhD, FACR Geoffrey Clarke, PhD, FACR Michael Dennis, PhD R. Edward Hendrick, PhD, FACR Carl Keener, PhD Jeff Masten, MS Moriel Nessaiver, PhD Joe Och, MS Donna Reeve, MS Priscilla Butler, MS, ACR Staff Member Dina Hernandez, RT, ACR Staff Member Leonard Lucey, JD, ACR Staff Member Pam Wilcox, MBA, ACR Staff Member © Copyright 2015, American College of Radiology. All rights reserved. Contents PREFACE . .vi REVISIONS . 3 Radiologist’s Section INTRODUCTION ..............................................4 DEFINITIONS. 6 A. Quality Assurance . 6 B. Quality Assurance Committee .........................6 C. Quality Control . 6 RADIOLOGISTS’ RESPONSIBILITIES ............................8 A. The Supervising Radiologist ...........................8 B. All MRI Radiologists (Interpreting Physicians) . 8 C. Interpretive Quality Assurance .........................9 D. Radiologist’s Leadership Role in MRI Quality Control . 9 E. MRI Quality Assurance Procedures Manual .............10 OTHER PROFESSIONALS’ RESPONSIBILITIES ..................12 A. The Responsibilities of the Qualified Medical Physicist or MRI Scientist .........................................12 B. Baseline Measurements and Action Limits. 12 C. Purchase Specifications and Acceptance Testing ......12 D. MRI QC Technologist’s Responsibilities . .13 E. Quality Control of Hard-Copy and Soft-Copy Images ...14 CONCLUSION ...............................................15 REFERENCES ...............................................16 A. Downloadable from ACR Website .....................16 B. Other Publications . .16 MRI Technologist’s Section REVISIONS. 19 INTRODUCTION .............................................20 IMPORTANT POINTS .........................................22 A. Quality Control Testing Frequency ....................22 Magnetic Resonance Imaging Quality Control Manual iii Contents B. Designated Quality Control Technologist(s) . .22 C. Quality Control Log . .23 D. Quality Control Data Review . .23 E. Alternative Phantoms ................................23 F. Alternative Procedures ................................24 G. Action Limits .........................................24 TECHNOLOGIST’S WEEKLY MRI QUALITY CONTROL . .25 A. Setup and Table Position Accuracy ....................26 B. Axial Image Data: Prescan Parameters . 29 C. Image Data Measurements ...........................32 FILM PRINTER QUALITY CONTROL ...........................47 VISUAL CHECKLIST ..........................................51 REFERENCES . .52 APPENDIX ..................................................53 Medical Physicist/MRI Scientist’s Section REVISIONS . .56 ROLE OF THE QUALIFIED MEDICAL PHYSICIST OR MRI SCIENTIST IN THE IMAGE QC PROGRAM ................................57 A. Changes Since 2004 Version ..........................58 ESTABLISHING THE QUALITY CONTROL PROGRAM ...........60 A. Phantom Section .....................................60 B. Methods and Action Limits for Weekly Quality Control Tests. .61 C. Establishing Action Limits for Weekly MR Image Quality Control Tests .........................................62 ANNUAL MRI SYSTEM PERFORMANCE EVALUATION ..........70 A. Magnetic Field Homogeneity .........................72 1. Spectral Peak Option ...............................74 2. Bandwidth-Difference Option. .74 3. Phase Map Option. .77 4. Phase-Difference Map Option. .80 iv Magnetic Resonance Imaging Quality Control Manual Contents B. Slice-Position Accuracy ...............................87 C. Slice-Thickness Accuracy. .88 D. Radiofrequency Coil Checks ..........................90 1. Volume Coil Tests . .96 2. Surface Coil Tests ..................................103 3. RF Array Coils. .105 E. Soft-Copy (Monitor) Quality Control ..................109 F. MR Safety Program Assessment. .111 REFERENCES . .113 APPENDIX .................................................116 A. MRI Equipment Evaluation Summary Form ...........116 B. MRI Safety Program Assessment Checklist ............116 C. Hard-Copy (Film) Quality Control Operating Levels ....116 Magnetic Resonance Imaging Quality Control Manual v Preface PREFACE The Magnetic Resonance Imaging Accreditation Program of the American College of Radiology was established to attest to the quality of the performance of magnetic resonance imaging at accredited facilities. Accreditation received through this program assures patients, referring physicians and others that magnetic resonance imaging studies at accredited sites are only performed by well-trained and competent personnel using properly functioning equipment. All sites accredited by the American College of Radiology in magnetic resonance imaging have agreed to carry out a continuous program of magnetic resonance imaging equipment quality control. The Committee on MRI Accreditation has received many inquires regarding what would constitute an adequate magnetic resonance imaging equipment quality control program and what the appropriate roles of various health care professionals at these clinics should be. This manual is designed to assist facilities in testing and maintaining their magnetic resonance imaging equipment in accordance with the broad principles delineated in the ACR-AAPM Technical Standard for Diagnostic Medical Physics Performance Monitoring of Magnetic Resonance Imaging Equipment [Res. 34–2014]. The committee has applied these principles to describe which personnel are responsible for which specific tasks and delineate methods for evaluating equipment performance with many tests using the American College of Radiology’s magnetic resonance imaging phantom. Members of the ACR Subcommittee on MRI Accreditation physics who generously donated their time and experience to produce the ACR Magnetic Resonance Imaging Quality Control Manual are listed on the title page. Special thanks goes to Pamela Wilcox, executive vice president of Quality & Safety, and Leonard Lucey, senior director of accreditation, who have kept this project and the other ACR accreditation programs on track over the years. Anthony Scuderi, M.D. Chairman, ACR Committee on MRI Accreditation vi Magnetic Resonance Imaging Quality Control Manual 2015 Magnetic Resonance Imaging QUALITY CONTROL MANUAL Radiologist’s Section Contents REVISIONS ...................................................3 INTRODUCTION ..............................................4 DEFINITIONS .................................................6 A. Quality Assurance ...................................6 B. Quality Assurance Committee ........................6 C. Quality Control ......................................6 RADIOLOGISTS’ RESPONSIBILITIES ............................8 A. The Supervising Radiologist ..........................8 B. All MRI Radiologists (Interpreting Physicians) .........8 C. Interpretive Quality Assurance ........................9 D. Radiologist’s Leadership Role in MRI Quality Control ...9 E. MRI Quality Assurance Procedures Manual .......... 10 OTHER PROFESSIONALS’ RESPONSIBILITIES ................. 12 A. The Responsibilities of the Qualified Medical Physicist or MRI Scientist ....................................... 12 B. Baseline Measurements and Action Limits ........... 12 C. Purchase Specifications and Acceptance Testing .... 12 D. MRI QC Technologist’s Responsibilities ............. 13 E. Quality Control of Hard-Copy and Soft-Copy Images . 14 CONCLUSION .............................................. 15 REFERENCES .............................................. 16 A. Downloadable from ACR Website ................... 16 B. Other Publications ................................. 16 2 Magnetic Resonance Imaging Quality Control Manual I. Revisions REVISIONS Date Page(s) Section Description of Revisions RADIOLOGIST’S SECTION RADIOLOGIST’S Magnetic Resonance Imaging Quality Control Manual Return to Table of Contents – 3 II. Introduction INTRODUCTION Magnetic resonance imaging (MRI) is now a mature and widely used imaging method. There is significant variability, however, in the quality of MRI exams performed at different sites. Achieving the full potential of MRI requires careful attention to quality assurance (QA), both in regard to equipment performance and to the execution of imaging studies. In response to the concerns of both referring physicians and those institutions reimbursing for the costs of performing MRI, the American College of Radiology (ACR) has initiated a voluntary MRI accreditation program. This program has followed the approach of the ACR Mammography Accreditation Program, which has established practices and standards for QA and quality control (QC) in mammography. The MRI Accreditation Program looks at the general practice of clinical MRI. Specific clinical examinations and QC data are required. Sites are asked to send their best examinations for selected clinical studies for peer-review. As part of the program, QC data must be collected using a head phantom test object. During this time, the ACR has also developed specific standards related to MRI and appropriateness criteria. With improved standards, widely accepted acknowledgment of the worth of accreditation, and a growing body of