|
The IAC Standards
and Guidelines |
1.1B FDA
approved MRI device(s) must be available.
1.1.1B The
MRI unit must be capable of performing multiplanar images using T1, T2 and STIR
sequences with a field of view large enough to consistently image all relevant
anatomy in the region of interest.
1.1.2B Equipment
specifications and performance must meet all state, federal and local
requirements.
(See Guidelines below for further
recommendations.)
1.2B The
Equipment Quality Control (QC) documentation must consist of MRI system
installation acceptance testing and acceptance testing following a major
upgrade
1.2.1B The manufacturer’s representative, service engineer or Qualified Medical Physicist or qualified expert must perform the acceptance testing.
1.2.2B
The system parameters must be compared to the manufacturer’s system
specifications or industry standards and reviewed by appropriate staff,
recommended to be a Qualified Medical Physicist. Acceptance testing must include (where applicable to the scanner):
1.2.2.1B magnetic
field homogeneity;
1.2.2.2B geometric accuracy/gradient
and RF calibration;
1.2.2.3B slice
thickness accuracy;
1.2.2.4B slice
position accuracy;
1.2.2.5B signal image
quality performance;
i. high contrast spatial resolution;
ii. artifact assessment; and
iii. low contrast detectability/contrast-to-noise ratio
1.2.2.6B performance testing of each coil used clinically:
i. physical/visual inspection;
ii. RF transmitter gain/attenuator verification;
1.2.2.7B image acquisition monitor performance;
1.2.2.8B inspection of physical and mechanical integrity of system;
1.2.2.9B establishment
and documentation of baselines and action limits for all parameters
measured at acceptance testing (for future QC and preventative
maintenance use).
1.3B Routine
(daily and periodic) quality control (QC) tests are to be conducted according
to performance measurements as outlined by the manufacturer’s system
specifications or industry standards.
1.3.1B The
daily QC assessments must include (where applicable to the scanner):
1.3.1.1B proper
function of audible and visual patient safety equipment;
1.3.1.2B center
frequency (CF) tests;
1.3.1.3B signal-to-noise
ratio (SNR);
1.3.1.4B image
uniformity; and
1.3.2B Periodic QC assessments must include (where appropriate to the scanner):
1.3.2.1B setup and positioning accuracy (mechanical check);
1.3.2.2B transmitter gain or attenuation (reference [head or other] coil RF calibration);
1.3.2.3B geometric accuracy along each of the three major axes (gradient calibration);
1.3.2.4B high-contrast spatial resolution;
1.3.2.5B low-contrast detectability/contrast-to-noise ratio (CNR); and
1.3.2.6B acquisition workstation monitor quality control.
1.3.3B Deviations
from established thresholds must be documented and corrective action taken
where appropriate.
1.3.4B Preventive
maintenance (PM) service is required per the manufacturers’ recommendations
but not less than annually for each MRI scanner at the facility.
1.3.5B A
manufacturer’s service engineer and/or the MRI site’s
representative, who has been properly trained to maintain the equipment, must
perform the preventive maintenance.
1.3.6B The PM quality
control assessment must include (but need not be limited to) the following (on an annual basis):
1.3.6.1B Performance testing of each coil used clinically:
i. physical/visual inspection;
ii. RF transmitter gain/attenuator verification;
i. high contrast spatial resolution;
ii. artifact assessment; and
(See Guidelines below for further
recommendations.)
1.4B All QC results
must be documented and reviewed.
1.4.1B A written report
of the acceptance tests must be maintained at the MRI facility. The report must
include the QC tests performed, the results as compared to manufacturer’s
or industry guidelines, recommendations to the facility (if any) and must be
signed and dated by the person performing the tests. The tests performed must
also be archived on the system or a separate device for future reference.
1.4.2B A complete report
of PM, quality control tests and service records must be maintained at the MRI
facility. The reports must be signed and dated by the person(s) performing the
tests.
1.4.3B A complete service
record for all ancillary MRI equipment must be maintained at the MRI facility.
The reports must be signed and dated by the person(s) performing the tests.
(See Guidelines below for further
recommendations.)
1.1.2B
Comment: The requirements may include maximum rate of change of magnetic field
strength (dB/dt), specifications of maximum static magnetic field strength,
maximum auditory noise levels and maximum radiofrequency power deposition
(specific absorption rate).
1.2B
Quality control tests, standards, thresholds, timelines and results should be
reviewed and discussed on a regular basis by appropriate staff.
Quality control tests should be performed according to the manufacturer’s
performance standards by the MRI technologist, service engineer, medical
physicist, or qualified expert on a timely basis.
1.3 B A major upgrade is a hardware upgrade that replaces one or more of the following: main magnet, gradient coil, body coil, gradient amplifiers, RF transmitter, and/or RF receiver subsystem. This means hardware with new/different specifications and capabilities. A system upgrade that results in the system being assigned a new serial number by the manufacturer is considered a major upgrade. In addition, a limited-scope acceptance test should be performed for routine replacement of individual coils and for upgrade replacements of individual coils. Acceptance testing should be considered after repairs to a system resulting from major damage including, but not limited to, magnet quench, fire, flooding, and so forth.
1.4B Periodic evaluations should be established at weekly, monthly, or quarterly intervals in the facility’s quality assurance policies and procedures.
1.3.6B Annual QC assessments may be performed by the service engineer as part of PM service or may be performed by the Qualified Medical Physicist.
1.3.2.2B The
reference coil is the coil designated by the facility for use in
periodic QC assessments. This is usually the head coil for MRI systems
equipped with one. If the manufacturer directs the use of a specific
coil for daily or other routine QC procedures, this would be a
reasonable choice for the reference coil. The reference coil should be
able to fit the phantom(s) used for the periodic QC assessments and
facilitate reproducible positioning of the phantom and coil. The
reference coil used for daily and periodic QC shall be documented for
the facility’s QA program.