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Quality Management for Radiological Equipment. David Huang, PhD, DABR Chief, Medical Physics Memorial Sloan-Kettering Cancer Center. Introductions. Every patient with cancer deserves to receive the best possible management to achieve cure, long-term tumor control or palliation
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Quality Management for Radiological Equipment David Huang, PhD, DABR Chief, Medical Physics Memorial Sloan-Kettering Cancer Center
Introductions • Every patient with cancer deserves to receive the best possible management to achieve cure, long-term tumor control or palliation • Every patient comes for diagnosis deserves to receive the correct diagnosis with minimum side effect from radiation to get a earlier detection of disease
Introductions • Radiation equipment is a great device for diagnostics and treatment, however, the nature of radiation may cause radiation-induced side effects to the patients • Balance between “Benefit” and “Risk” is an essential for radiation equipment use • Cost effectiveness also an important issue under nowadays medical environment
Introductions • The comprehensive Quality Management program has clinical, physical, and administrative components and its implementation requires the team work of all personnel • The physician, physicist, and technologist along with other member of the team should collaborate on developing a written QA program for Quality Management program
Introductions • The QA program details the quality control tests and procedures, their frequency, the action criteria, the records required and the personnel required to perform them • The QA program should have a QA committee and include a feedback mechanism to that committee so that the cause of any shortcomings can be addressed and corrected
Introductions • JCAHO requires that QA in radiation field be a part of the hospital’s QA program, and more recently, that a program of continuous quality improvement be implemented • JCAHO states that “the physician director of the radiation services is responsible for ensuring that the QA program is implemented
Introductions • A policies and procedures manual is required by JACHO. It should be updated as procedure changed, and should be reviewed once per year and signed and dated by the appropriate section head • External review of the QA programs and procedures by qualified experts is an important aspect of a quality audit
QA Test of Radiation Equipment • Test Category: -Safety -Mechanical -Dosimetry -Image Quality • Test Frequency: Daily, Weekly, Monthly, Quarterly, Semi-annual, and Annual
Radiation Therapy Equipment • TG Reports are good references/standards for QA procedures • Federal and States start to monitor Linac QA as well as Co-60 machine • For new machine, you need to submit Acceptance/commissioning results and radiation survey results • Inspector visit site once per year for Policy/procedure manual and QA records
Radiology Equipment QA • TG reports are also good reference/standard for QA procedures • Inspector visits site once per year for policy and procedure manual and QA record • Special requirement for Mammograph unit, QA procedure, personnel qualification, site accreditation… • MR is monitored by medical society
General Items for Radiology • Film Darkroom QA: -Darkroom environment -Viewbox QC • Processor QA: -Chemical activities -Processor cleaning process -Processor monitoring
QC of Radiographic/FluoroscopicEquipment • Visual inspections • Environment inspections • Performance testing: Reproducibility of exposure, Focal spot size, Filtration check, kVp accuracy, mA linearity, High- and low-contrast resolution, Spatial resolution, SSD, distortion, image noise…..
NY State Guidelines for CT QA • Purpose The Department of Health has implemented this program to reduce radiation exposure, optimize diagnostic image quality and foster facility involvement in the responsibility for Quality Assurance (QA)
NY State Guidelines for CT QA • ALARA This guideline has been established on the ALARA principle to ensure that the benefits of ionizing radiation exceed the risks to the individual and the public health and safety
NY State Guidelines for CT QA • Limits and Standards The control limits and standards used in this guide have been taken from Federal Performance Standard for Diagnostic X-ray Equipment (21CFR1020), Part 16, and AAPM Report #74. Equipment problems should be documented and shall be corrected with appropriate documentation within thirty (30) days of discovery
NY State Guidelines for CT QA • Responsibility: Large facilities can absorb the responsibilities and structure for CT QA into their existing committee that is responsible for overseeing diagnostic radiology
NY State Guidelines for CT QA • Responsibility: For small facilities, radiation safety and QA is the responsibility of the physician who registers the equipment The responsibility for CT equipment PM/QC testing falls upon several professional groups, Medical Physicists, Radiologic Technologist, in-house engineering, and manufacturer service representatives
NY State Guidelines for CT QA • Records - Manual - Equipment Records - Processor and Sensitometer Logs - QC Records for Test Equipment - radiation Safety Policies and Procedures
NY State Guidelines for CT QA • Equipment Monitoring Each facility shall have QC tests to monitor equipment performance and maintain records of data collected If at the time of inspection, significant equipment malfunctions are found, the facility may be required to perform more frequent testing to ensure good diagnostic image quality
NY State Guidelines for CT QA • Equipment Monitoring This guide describes a basic Radiation Safety/QA Program and represents only a portion of the QC tests your facility may choose to perform as part of your individual program Appropriate QC testing must be conducted whenever major maintenance (X-ray tuble replacement) or a change in equipment operation (software change) occurs
NY State Guidelines for CT QA • Equipment Monitoring: each day of operation - Equipment functioning: check any malfunction, evaluate the mechanical and electrical safety - CT number accuracy of water, Image noise, Image uniformity, and Artifact evaluation shall be performed daily using a common technique setting with a head size phantom
NY State Guidelines for CT QA • Equipment Monitoring: monthly - Image slice thickness or Slice sensitivity profile - Slice positioning accuracy - CT number scale accuracy - Hard copy device
NY State Guidelines for CT QA • Equipment Monitoring: semi annually - Dose profile width - Spatial resolution - Low contrast detestability • Equipment Monitoring: annually - Patient dose
NY State Guidelines for CT QA • Equipment Monitoring: on installation of new tube All weekly and monthly tests must be completed before patient examinations commence. All semi-annual and annual tests must be completed within thirty days of tube replacement
NY State Guidelines for CT QA • Equipment Monitoring: on installation of new unit Same as new tube, plus - Half-value layer - Radiation protection survey - Scan protocols - Log book
Mammography Quality Standards Act • Before 1992, quality standards for Mammo. were the responsibility of individual agencies • ACR began a voluntary Mammo. Accreditation Program (MAP) in 1987 • The Mammo. Quality Standards Act (MQSA) passed on Oct. 27, 1992 • This law requires all facilities (except VA hospital) be accredited by an approved accreditation body and certified by the Secretary of the Health and Human Service to legally provide Mammo service.
MQSA • Accreditation of Mammo. facilities by private nonprofit organization (ACR) or State agencies that have met the standards established by FDA • An annual Mammo. facility physics survey, consultation, and evaluation performed by a qualified medical physicist • Annual inspection of Mammo. facility by FDA-certified federal and state agencies • Establishment of initial and continuing qualification standards for MD, Physicist, Technologist, and Inspector
MQSA • Specification of board or organization eligible to certify the adequacy of training and experience of Mammo. personnel • Establishment of quality standards for Mammo. equipment and practices • Establishment of a National Mammo. QA Advisory Committee (NMQAAC) to advise FDA of appropriate quality standards • Standards governing record keeping for exam files and requirements for Mammo. reporting and exam notification by physician
MQSA • Specific regulations for accrediting bodies • General facility provision: specific guidelines of Mammo. report, definition of the responsibilities of facility personnel, review of Mammo. Medical outcomes audit data at least every 12 months… • Personnel regulations for interpreting physicians, medical physicists, and mammographers • New equipment requirements to reduce the cost of replacing or retrofitting equipment before its normal replacement date
Quality Control Responsibilities • Radiologist (Interpreting Physician) - the primary responsibility for Mammo. QC is the lead interpreting physician • Medical Physicist - responsible for the QC evaluation of the Mammo. equipment • Radiologic Technologist (Mammographer) - responsible for QC measurements of the Mammo. equipment
Quality Control Responsibilities • Medical Physicist’s duties - Visual inspection of Mammo. Assembly - Collimation assessment - Focal spot size - kVp reproducibility - Beam quality assessment - Timer accuracy - AEC systems
Quality Control Responsibilities • Medical Physicist’s duties (continue) - Uniformity of screen speed - Breast entrance exposure - Average glandular dose - Image quality evaluation - Artifact evaluation - Collimation
Quality Control Responsibilities • Mammographer’s duties - Daily: Darkroom cleanliness Processor quality control - Weekly: Screen cleanliness Viewboxes and viewing conditions
Quality Control Responsibilities • Mammographer’s duties (continue) - Monthly: Phantom image Visual inspection: SID, Field light… - Quarterly: Repeat analysis Archival quality
Quality Control Responsibilities • Mammographer’s duties (continue) - Semiannual: Darkroom fog Film-screen contact Compression
Quality Control Responsibilities • FDA inspection - Equipment performance: Collimation system Entrance skin exposure and exposure reproducibility Beam quality measurement Phantom image quality evaluation Processor evaluation and darkroom fog measurement - Records
Mammography QC/QA Quality control and quality assurance for mammographic equipment and procedures are mandatory for compliance with MQSA. Proper documentation of these procedures is essential for a facility to remain accredited to perform mammographic procedures
QA/QC in Nuclear Medicine • JCAHO states: There shall be quality control policies and procedures governing nuclear medicine activities that assure diagnostic and therapeutic reliability and safety of patients and personnel
Gamma Camera Quality Control • Energy resolution and photopeaking: daily and before each new radionuclide used • Counting rate limits: daily • Field uniformity: daily, after repair • Spatial resolution: weekly, after repair • Spatial linearity: weekly, after repair • Sensitivity: quarterly
SPECT Camera Quality Control • Uniformity correction flood : weekly • Center of Rotation: weekly for every collimator used for tomography • Pixel size: monthly • Cine to detect patient motion: after each patient acquisition
PET Quality Control • Radial, tangential, and Axial resolutions • Sensitivity • Linearity • Uniformity • Attenuation accuracy • Scatter determination • Dead time corrections
Conclusions and Suggestions • For high standards Radiotherapy, we need a comprehensive QA program for RT • Lots of new treatment techniques and new treatment equipment are implemented clinically for Radiotherapy, to make use of these techniques and equipment “efficiently”, we need a comprehensive QA program for RT • To improve the treatment outcomes while lower the treatment side effect, we need a comprehensive QA program for RT
Conclusions and Suggestions • “Benefits vs Risks” is always an essential for diagnostic radiology. To make benefit “over” risk for any diagnosis in radiology, we need a comprehensive QA program for radiology and nuclear medicine • Patient dose now becomes a “major” concern for people undergo diagnosis with radiation, especially for routine checkout. For this concern, we need a comprehensive QA program for radiology and nuclear medicine
Conclusions and Suggestions • The new study from NIH shows that “there is always a risk from radiation, doesn’t matter how small amount of radiation received”, therefore, radiation safety to the patients and staffs becomes more important than ever. To assure the radiation safety issue in the medical radiation fields, we need a comprehensive QA program for Radiotherapy, Diagnostic Radiology, and Nuclear Medicine
Conclusions and Suggestions • In US, Government and accreditation agencies now mandate procedures to ensure that equipment is functioning within accepted standards and that it is operated properly. • Such procedures must be also appropriately documented. • Because of increasing QA tasks for technologists, they now need additional knowledge. The ARRT has recognized this need by offering an advanced level examination in Quality Management in 1997.
Conclusions and Suggestions • My suggestions are, and I am willing to help if there is a necessity: - A team to study the feasibility of “QA program implementation” for Radiology and Nuclear Medicine - A team to address the “outline of QA program” - A team to develop the QA technique as user’s reference - A team from overseas to exchange the experience and to provide updated information