Current through Register Vol. 48, No. 39, March 25, 2024
Subpart 1.
Applicability.
Computed tomography systems designed for visualization of
head and soft tissues of the neck must meet requirements of this chapter
and:
A. nationally recognized
standards such as Code of Federal Regulations, title 21, section
1020;
B. the manufacturer's
specifications; or
C. part
4731.1100.
Subp. 2.
Facility design requirements.
A.
The control panel must be mounted in a permanently protected area outside the
computed tomography room and meet the requirements of part
4732.0355, subpart
2.
B. If the control area is within the CT room,
the requirements for a control booth in part
4732.0355, subpart
2, must be
followed.
C. The operator is
required to remain in the protected area during the entire exposure.
D. Viewing systems must be windows, mirrors,
closed-circuit television, or an equivalent able to provide continuous operator
observation of the patient from the control panel during irradiation.
E. Provision must be made for two-way audio
communication between the patient and operator at the control panel.
Subp. 3.
Radiation
surveys.
All computed tomography systems installed 90 days after
November 5, 2007, and those systems not previously surveyed, must have a
radiation survey to identify radiation levels at the control panel and the
spaces adjoining the CT room. In addition, the surveys must be completed after
any change in the facility or equipment that might cause a significant increase
in radiation hazard. The survey must be maintained by the registrant according
to part
4732.0330.
Subp. 4.
Equipment performance
measurements.
A. The registrant must
ensure that the equipment performance measurement procedures are performed at
intervals not to exceed 24 months according to:
(1) nationally recognized standards, such as
Code of Federal Regulations, title 21, section 1020;
(2) the manufacturer's specifications;
or
(3) part
4732.1100; and
(4) processing requirements in part
4732.1100.
B. The equipment performance measurement of
the radiation output of the CT x-ray system must be performed by a registered
service provider.
C. The equipment
performance measurements of a CT system must be performed at intervals not to
exceed 24 months or after change or replacement of components that could cause
an increase in radiation hazard or that could result in the minimum performance
criteria in part
4732.1100 not being met.
D. The measurements of the radiation output
of a CT system must be performed with a calibrated dosimetry system. The
calibration of such system must be traceable to a national standard. The
dosimetry system must have been calibrated within the preceding 24
months.
E. CT dosimetry phantoms
must be used in determining the radiation output of a CT system. The phantoms
must comply with Code of Federal Regulations, title 21, section 1020.33 or
equivalent phantom.
F. The dose
measurements must be made for standard head scan mode of operation used at the
facility.
G. The image quality
measurements must be made using a typical clinical technique in the standard
head scan mode of operation.
Subp.
5.
Spot checks.
The registrant must ensure the spot checks for the computed
tomography equipment in this part are performed at intervals not to exceed 12
months to verify the system's integrity.
A. The spot check procedures must be written
procedures developed by the manufacturer or a registered service
provider.
B. All spot checks must
be included in the equipment performance measurements and at time intervals and
system conditions specified by the manufacturer or a registered service
provider.
C. The spot check
procedures must incorporate the use of a CT image quality phantom to provide an
indication of contrast scale, noise, the resolution capability of the system
for low and high contrast objects, and must measure the mean computed
tomography noise (CTN) for water or other reference material.
D. Spot checks must include acquisition of
images obtained with the CT image quality phantoms using the same processing
mode and CT conditions of operation that are used to perform equipment
performance measurements according to part
4732.1100. The images must be
maintained until a new equipment performance test is performed.
E. Records must be retained as:
(1) photographic copies of the images
obtained from the image display device; or
(2) images stored in digital form on a
storage medium compatible with the CT system.
F. Documentation of the spot checks must be
maintained according to part
4732.0330.
Subp. 6.
Equipment performance
measurements performed by the CT operator.
In addition to the equipment performance measurements
described in subpart
4, an operator must:
A. complete daily and monthly equipment
performance procedures according to part
4732.1100 or those equipment
performance procedures designed by the manufacturer and include all processing
procedures in part
4732.0510; and
B. complete acquisition of images obtained
with a CT phantom recommended by the manufacturer using the same processing
mode and CT conditions of operation that are used to perform the equipment
performance measurements required by part
4732.1100.
Subp. 7.
Program review.
The registrant or radiation safety officer must review, sign,
and date the operator's equipment performance measurements at intervals not to
exceed 12 months.
Subp. 8.
Operating procedures.
The registrant must ensure that:
A. the CT system is operated by an individual
who:
(1) after January 1, 2008, is a licensed
practitioner of the healing arts, or individuals who meet the requirements in
Minnesota Statutes, section
144.121,
subdivision 5;
(2) has been
specifically trained by the equipment manufacturer or equivalent; and
(3) has training on appropriate positioning
and anatomy for the use of the equipment in the facility; and
B. information of the system is
available at the control panel regarding the operation. The information must
include the following:
(1) a current technique
chart available at the control panel, which specifies for each routine
examination, the CT conditions of operation and the number of scans per
examination; and
(2) instructions
on the use of the CT dosimetry or image quality phantoms including the
allowable variations for the indicated parameters.
Subp. 9.
Corrective
actions.
A. Correction of the problem
must take place and be verified by performing the equipment performance
measurements according to:
(1) Code of
Federal Regulations, title 21, section 1020;
(2) the manufacturer's specifications;
or
(3) part
4732.1100.
B. The equipment must not be used until
corrective actions have been taken, verified, and documented, if the equipment
performance measurement or spot check of the CT system indicates that a system
operating parameter has exceeded a tolerance established:
(1) in part
4732.1100;
(2) by the manufacturer; or
(3) by a registered service
provider.
Subp.
10.
CT fluoroscopic procedures.
If the equipment has the capabilities of performing
fluoroscopic procedures, the x-ray control may be operated in the CT room and
essential personnel may remain in the room during the fluoroscopic procedures
provided they:
A. have been trained on
radiation safety issues of CT;
B.
are wearing personal protective garments; and
C. have individual personal monitoring
devices.
Subp. 11.
Records.
The registrant will ensure that the required documentation is
maintained according to part
4732.0330.
Statutory Authority: MS s
144.12