TABLE OF CONTENTSI. INTRODUCTION: WHY ULTRASOUND QUALITYII. TEST SCHEDULEIII. PERFORMING THE BASELINE TESTSIV. SUGGESTED ACTION LEVELS FOR IMAGEV. TEST OBJECT (PHANTOM) DESIGN ANDVI. COMPUTERIZED IMAGE ANALYSISVII. QUALITY CONTROL TESTSACKNOWLEDGMENTSAPPENDIX A: ABBREVIATED PERFORMANCEAPPENDIX B: QUALITY CONTROL FORMSAPPENDIX C: EXAMPLES OF POSSIBLEReal-timeB-mode ultrasound quality control test proceduresa…Report of AAPM Ultrasound Task Group No. 1Mitchell M. Goodsittb)and Paul L. CarsonDepartment of Radiology, University of Michigan, Ann Arbor, Michigan 48109-0030Scott Wittc)Gammex RMI, Middleton, Wisconsin 53562-0327David L. HykesDepartment of Radiation Therapy, St. Joseph Hospital and Health Center, Lorain, Ohio 44052James M. Kofler, Jr.Department of Radiology, Mayo Clinic, Rochester, Minnesota 55904~Received 30 March 1998; accepted for publication 3 June 1998!@S0094-2405~98!02608-X#TABLE OF CONTENTSI. INTRODUCTION: WHY ULTRASOUNDQUALITY CONTROL?....................... 1385II. TEST SCHEDULE.......................... 1386III. PERFORMING THE BASELINE TESTS. . ..... 1386A. Selecting instrument control settings.......... 1386B. Determining baseline values................ 1386C. Selecting the action levels.................. 1387IV. SUGGESTED VALUES FOR IMAGEQUALITY INDICATORS.................... 1387V. TEST OBJECT ~PHANTOM! DESIGNREQUIREMENTS.......................... 1387VI. COMPUTERIZED IMAGE ANALYSIS........ 1389VII. QUALITY CONTROL TESTS. .............. 1389A. Frequently performed quality control tests..... 13891. Physical and mechanical inspection....... 13892. Display monitor setup and fidelity........ 13903. Image uniformity...................... 13914. Depth of penetration/visualization......... 13925. Photography ~hard copy! fidelity.......... 13936. Distance accuracy...................... 1394B. Less frequent quality control tests............ 13941. Anechoic object imaging................ 13942. Axial resolution....................... 13963. Lateral resolution or response width. . ..... 13974. Ring down or dead zone. ............... 13985. Slice thickness or elevational focus........ 1399C. Film sensitometry......................... 14001. Establishing operating levels............. 14012. Control films and film emulsion crossover.. 14013. Example of performing a crossover....... 14014. Processing sensitometry strips............ 1402ACKNOWLEDGMENTS ...................... 1402APPENDIX A: ABBREVIATED PERFORMANCETEST INSTRUCTIONS ....................... 1402APPENDIX B: QUALITY CONTROL TESTFORMS ..................................... 14041. Physical and mechanical inspection.......... 14042. Hardcopy and display monitor fidelity........ 14043. Image uniformity......................... 14044. Depth of visualization..................... 14045. Vertical and horizontal distance accuracy...... 14046. Anechoic object perception................. 14057. Axial resolution.......................... 14058. Lateral resolution......................... 14059. Ring down or dead zone................... 1405APPENDIX C: EXAMPLES OF PHANTOMDESIGNS ................................... 1405REFERENCES . . . . . . . . . . . . . . . . . . . . ........... 1406I. INTRODUCTION: WHY ULTRASOUND QUALITYCONTROL?It is sometimes argued that there is no need for ultrasound~US! quality control ~QC! testing because ~1! the new ma-chines are very reliable and rarely break down, and ~2! thesonographer will detect image quality defects during normalscanning. Although both of these statements may be true,they do not necessarily negate the utility of US QC tests. Aprimary reason is that a set of periodic definitive measure-ments for each transducer and US unit can identify degrada-tion in image quality before it affects patient scans. Anotheris that when equipment malfunction is suspected, QC testscan be employed to determine the source of the malfunction.Even equipment that is under warranty or service contractshould be checked periodically. QC tests can verify thatequipment is operating correctly and repairs are done prop-erly.A quality assurance ~QA! program involves many activi-ties including: quality control testing, preventive mainte-nance, equipment calibration, in-service education of sonog-raphers, bid specification writing and bid responseevaluation, acceptance testing of new equipment, and evalu-ation of new products.1The purpose of the present documentis to describe routine ultrasound QC tests to be performed byor under the supervision of a medical physicist. Descriptionsof other QA activities, in particular acceptance testing of USequipment, are beyond the scope of this document. Further1385 1385Med. Phys. 25 „8…, August 1998 0094-2405/98/25„8…/1385/22/$10.00 © 1998 Am. Assoc. Phys. Med.information on ultrasound QC tests can be found in otherdocuments.2–5The following is a detailed set of instructions for settingup and performing ultrasound QC tests. An abbreviated in-struction set is also included in Appendix A for the opera-tor’s convenience. Examples of individual QC test forms areincluded in Appendix B, and examples of possible phantomdesigns are provided in Appendix C.II. TEST SCHEDULEThere is a strong commitment to performing at least oncea year comprehensive tests of x-ray imaging equipment suchas mammographic and fluoroscopic units. Depending uponthe complexity of the x-ray equipment, and the number andnature of the tests, the entire set of tests is completed inabout 1–8 h. There are no factors in an US unit which wouldindicate the need for more frequent thorough QC evaluationsthan is needed for general radiography, so long as servicingis competent and the US technologists are well trained andattentive. However, in the interest of discovering problemsbefore they become serious, it is recommended that certaintests of short duration be performed more frequently. Theseare termed the ‘‘quick scan’’ tests. They include displaymonitor fidelity, image uniformity, depth of visualization,hard copy fidelity, vertical distance accuracy, and horizontaldistance accuracy. Only the most frequently employed trans-ducer is evaluated in these tests. The quick scan tests plus aphysical and mechanical inspection should be performed ev-ery three months for mobile and emergency room systemsand every six month for others. The total time commitmentfor the quick scan tests plus the physical and mechanicalinspection should be about 15 min per US unit. The morethorough set of tests, analogous to