Current through September 17, 2024
This section applies to registrants using computed tomography
(CT) systems and cone beam computed tomography (CBCT) systems.
008.01 DEFINITIONS.
In addition to the definitions provided in 180 NAC 1-002 and 180
NAC
6-002, the following definitions apply
to 180 NAC 6-008.
008.01(A)
CONTRAST SCALE. Contrast scale has the same meaning as
21 CFR §
1020.33(b).
008.01(B)
COMPUTED TOMOGRAPHY
(CT) CONDITIONS OF OPERATION. Computed tomography (CT) conditions
of operation are all selectable parameters governing the operation of a
computed tomography (CT) system including, but not limited to, nominal
tomographic section thickness, filtration, and the technique factors as defined
in this chapter.
008.01(C)
COMPUTED TOMOGRAPHY (CT) NUMBER. Computed tomography (CT) number has the same
meaning as set out in
21 CFR §
1020.33(b). 008.01(D) NOISE.
Noise has the same meaning as set out in
21 CFR §
1020.33(b).
008.01(E) NOMINAL TOMOGRAPHIC
SECTION THICKNESS. Nominal tomographic section thickness has the
same meaning as set out in
21 CFR §
1020.33(b).
008.01(F)
REFERENCE PLANE.
Reference plane is a plane which is displaced from and parallel to
the tomographic plane.
008.01(G) SCAN. Scan
is the complete process of collecting x-ray transmission data for the
production of a tomogram. Data can be collected simultaneously during a single
scan for the production of one or more tomograms.
008.01(H) SCAN
INCREMENT. Scan increment has the same meaning as set out in
21 CFR §
1020.33(b).
008.01(I) SCAN
SEQUENCE. Scan sequence has the same meaning as set out in
21 CFR §
1020.33(b).
008.01(J)
TOMOGRAPHIC
PLANE. Tomographic plane has the same meaning as set out in
21 CFR §
1020.33(b).
008.01(K) TOMOGRAPHIC SECTION.
Tomographic section has the same meaning as set out in
21 CFR §
1020.33(b).
008.02 COMPUTED
TOMOGRAPHY (CT) AND CONE BEAM COMPUTED TOMOGRAPHY (CBCT) EQUIPMENT
REQUIREMENTS. Computed tomography (CT) and cone beam computed
tomography (CBCT) equipment must meet the following requirements, except for
fluoroscopic systems capable of performing cone beam computed tomography
(CBCT).
008.02(A)
TERMINATION OF EXPOSURE. The timer must meet the
specifications of
21 CFR §
1020.33(f)(2).
008.02(B) TOMOGRAPHIC PLANE
INDICATION AND ALIGNMENT. Tomographic plane indication and
alignment must meet the specifications of
21 CFR §
1020.33(g).
008.02(C) BEAM-ON AND SHUTTER
STATUS INDICATORS AND CONTROL SWITCHES. Visual indication of x-ray
production and shutter status must meet the specifications of
21 CFR §
1020.33(h). Each emergency
button or switch must be clearly labeled as to its function.
008.02(D) INDICATION OF
CONDITIONS OF OPERATION. Visual indication of the conditions of
operation to be used during a scan or scan sequence must meet the
specifications of
21 CFR §
1020.33(f).
008.02(E) SCAN INCREMENT
ACCURACY. The accuracy of scanning increments must meet the
specifications of
21 CFR §
1020.33(i).
008.02(F) MEAN AND STANDARD
DEVIATION. The method used to calculate the mean and standard
deviation must meet the specifications of
21 CFR §
1020.33(j).
008.03 FACILITY DESIGN
REQUIREMENTS. Registrants using computed tomography (CT) equipment
must meet facility design specifications.
008.03(A) AURAL COMMUNICATION.
There must be two-way aural communication between the patient and
the operator at the control panel.
008.03(B)
VIEWING SYSTEMS.
Viewing systems must include the following:
(i) Windows, mirrors, closed-circuit
television, or an equivalent must be provided to permit continuous observation
of the patient during irradiation and must be located so the operator can
observe the patient from the control panel; and
(ii) When the primary viewing system is by
electronic means, an alternate viewing system, which may be electronic, must be
available for use in the event of failure of the primary viewing
system.
008.04 PLAN REVIEWS,
CALIBRATIONS, SPOT CHECKS, AND OPERATING PROCEDURES. Plan reviews,
calibration, spot checks and operating procedures for computed tomography (CT)
and cone beam computed tomography (CBCT) systems must meet the following
requirements..
008.04(A) PLAN
REVIEWS. For computed tomography (CT) and cone beam computed
tomography (CBCT) x-ray systems, the plan review required by 180 NAC 6-003.19
must be performed by, or under the direction of, a radiological medical
physicist or radiological health physicist meeting the requirements of 180 NAC
2-005.04(C)(ii). In addition, radiation surveys must be performed after any
change in the registrant's facility or equipment that might cause an individual
to receive a dose in excess of the limits prescribed in 180 NAC 4-005, 4-011 or
4-013.
008.04(B) PLAN
REVIEW RESULTS. The registrant must obtain a written report of the
results of the plan review from the radiological medical physicist or
radiological health physicist. A copy of the report must be maintained for
inspection by the Department.
008.04(C)
RADIATION CALIBRATIONS
OF COMPUTED TOMOGRAPHY (CT) AND CONE BEAM COMPUTED TOMOGRAPHY (CBCT)
SYSTEMS. The calibration of radiation output of computed
tomography (CT) or cone beam computed tomography (CBCT) system must be
performed by, or under the direction of, a radiological medical physicist or
radiological health physicist meeting the requirements of 180 NAC
2-005.04(C)(ii) who is physically present at the registrant's facility during
the calibration. Calibration procedures must be in writing.
008.04(C)(i)
FREQUENCY OF
CALIBRATION. The calibration of a computed tomography (CT) or cone
beam computed tomography (CBCT) system must be performed after initial
installation, prior to the first use on a patient, and at intervals specified
by a radiological medical physicist or radiological health physicist, not to
exceed two years. Additionally, a calibration must be performed by a
radiological medical physicist or radiological health physicist within 30 days
after any change or replacement of components that, in the opinion of the
radiological medical physicist or radiological health physicist, could cause a
change in the radiation output. Calibration of a computed tomography (CT)
system must include the spot-checks specified in 180 NAC 6-008.05(A)(ii).
Calibration of a cone beam computed tomography (CBCT) system must include the
quality control checks specified in 180 NAC 6-008.07(C).
008.04(C)(ii) DOSIMETRY SYSTEM.
The measurement of the radiation output of a computed tomography
(CT) or cone beam computed tomography (CBCT) system must be performed with a
calibrated dosimetry system. The calibration of that system must be traceable
to a national standard. The dosimetry system must have been calibrated within
the preceding two years.
008.04(C)(iii) DOSIMETRY
PHANTOMS. Computed tomography (CT) dosimetry phantom or phantoms
must be used to ensure the computed tomography (CT) system meets the
specifications of
21 CFR §
1020.33(b)(6).
008.04(C)(iv) HEAD, BODY, OR
WHOLE-BODY SCANS. A computed tomography (CT) system must be
calibrated for each type of head, body, or whole-body scan or scans performed
at the registrant's facility to ensure that the system meets the specifications
of
21 CFR §
1020.33(c)(2).
008.04(C)(v) RECORDS OF COMPUTED
TOMOGRAPHY (CT) CALIBRATIONS AND CONE BEAM COMPUTED TOMOGRAPHY (CBCT).
Records of calibrations performed must be maintained for
inspection by the Department.
008.05 SPOT CHECKS OF COMPUTED
TOMOGRAPHY (CT) EQUIPMENT. Spot-check procedures must be in
writing and must be developed by a radiological medical physicist or
radiological health physicist.
008.05(A)
SPOT-CHECK PROCEDURES.
Spot-check procedures must include the following:
(i) Use of a computed tomography (CT) phantom
or phantoms that meets the requirements of
21 CFR §
1020.33(d)(1);
(ii) A check of the contrast scale, noise,
nominal tomographic section thickness, spatial resolution of the system for low
and high contrast objects, and a measurement of the mean computed tomography
(CT) number of water or a reference material; and
(iii) Acquisition of images must be obtained
with the computed tomography (CT) phantom or phantoms using the same processing
mode and computed tomography (CT) conditions of operation used to perform
calibrations required by this chapter.
008.05(B) FREQUENCY OF
SPOT-CHECKS. All spot checks must be performed at the frequency
and under system conditions specified by a radiological medical physicist or
radiological health physicist.
008.05(C) SPOT-CHECK RECORDS.
Records of the spot-checks performed must be maintained for
inspection by the Department.
008.06 OPERATING PROCEDURES FOR
COMPUTED TOMOGRAPHY (CT) SYSTEMS. Registrants must develop written
operating procedures for computed tomography (CT) systems as follows.
008.06(A) OPERATION OF THE
COMPUTED TOMOGRAPHY (CT) SYSTEM. The system must only be operated
by an individual who has been specifically trained in its operation and meets
the requirements of 180 NAC 6-003.05.
008.06(B)
INFORMATION ON
OPERATION AND CALIBRATION. Information must be available in the
operator control area regarding the operation and calibration of the system.
The information must include:
(i) Dates of
the latest calibration and spot-checks and the location where the results of
those tests may be found;
(ii)
Instructions on the use of the computed tomography (CT) phantom or phantoms
including a schedule of spot-checks appropriate for the system, allowable
variations for the indicated parameters, and the results of the most recent
spot-checks performed on the system;
(iii) The distance in millimeters between the
tomographic plane and the reference plane if a reference plane is utilized;
and
(iv) A current technique chart
available at the control panel which specifies, for each routine examination,
the computed tomography (CT) conditions of operation and the number of scans
for each examination.
008.06(C) OPERATING PARAMETERS.
If the calibration or spot-check of the computed tomography (CT)
system identifies that a system operating parameter has exceeded a tolerance
established by the radiological medical physicist or radiological health
physicist, use of the system on patients must be limited to those permitted by
written instructions of the radiological medical physicist or radiological
health physicist.
008.07 CONE BEAM COMPUTED
TOMOGRAPHY (CBCT) SYSTEMS. In addition to other requirements of
this chapter, this section applies to registrants using with cone beam computed
tomography (CBCT) systems.
008.07(A) OPERATION OF THE CONE
BEAM COMPUTED TOMOGRAPHY (CBCT) SYSTEM. The cone beam computed
tomography (CBCT) system must only be operated by an individual who has been
specifically trained in its operation and meets the requirements of 180 NAC
6-003.05.
008.07(B)
BEAM ALIGNMENT. The x-ray field in the plane of the image receptor
must not exceed beyond the edge of the image receptor by more than two percent
of the source-to-image distance (SID) when the axis of the x-ray beam is
perpendicular to the plane of the image receptor. In addition, the center of
the x-ray field must be aligned with the center of the image receptor to within
2 percent of the source-to-image distance (SID).
008.07(C) QUALITY
CONTROL. The registrant must follow the quality control
recommendations of the manufacturer. If manufacturer recommendations are not
obtainable, the registrant must perform quality control on the cone beam
computed tomography (CBCT) system that has been developed by a radiological
medical physicist or radiological health physicist.
008.07(D)
INFORMATION FOR THE
CONE BEAM COMPUTED TOMOGRAPHY (CBCT) OPERATOR. The following
information must be readily available to the operator of the cone beam computed
tomography (CBCT) system:
(i) Instructions on
performing quality control on the cone beam computed tomography (CBCT) system;
(ii) The time interval for
performing quality control on the cone beam computed tomography (CBCT)
system;
(iii) The allowable uses of
the cone beam computed tomography (CBCT) system if a quality control check
identifies a system operating parameter has exceeded a tolerance established by
the manufacturer. If tolerances from the manufacturer are not obtainable, a
radiological medical physicist or radiological health physicist must establish
the tolerances and the cone beam computed tomography (CBCT) system must be
limited to those uses allowed by the radiological medical physicist or
radiological health physicist; and (iv) The results of the most recent quality
control completed on the cone beam computed tomography (CBCT)
system.