6 Colo. Code Regs. § 1007-1-6.9

Current through Register Vol. 47, No. 11, June 10, 2024

Section 6 CCR 1007-1-6.9 - Requirements for use of computed tomography (CT) imaging systems

6.9.1 Administrative Controls.

6.9.1.1 In addition to the provisions of 6.3 and 6.4, the requirements of 6.9 apply to equipment and associated facilities used for computed tomography.

6.9.1.2 Supervision and operation of a computed tomography system used on living humans shall be by an individual who has adequate radiation safety training and experience.

(1) Supervision shall be consistent with 6.3.1.6.

(2) Training and experience shall be as provided in 6.3.1.6.

6.9.1.3 The technical and safety information relating to the conditions of operation, dose information and imaging performance provided by the CT manufacturer shall be maintained by the facility for the life of the machine.

6.9.2 Each computed tomography facility shall meet the following equipment design and configuration requirements.

6.9.2.1 Termination of Exposure.

(1) Means shall be provided to terminate the x-ray exposure automatically by either de-energizing the x-ray source or shuttering the x-ray beam in the event of equipment failure affecting data collection.

(a) Such termination shall occur within an interval that limits the total scan time to no more than 110 percent of its preset value through the use of either a backup timer or devices that monitor equipment function.

(2) A visible signal shall indicate when the x-ray exposure has been terminated through the means required by 6.9.2.1(1).

(3) The operator shall be able to terminate the x-ray exposure at any time during a scan, or series of scans under CT x-ray system control, of greater than one-half second duration.

6.9.2.2 Tomographic Plane Indication and Alignment.

(1) For any single tomogram system, means shall be provided to permit visual determination of the tomographic plane or a reference plane offset from the tomographic plane.

(2) For any multiple tomogram system, means shall be provided to permit visual determination of the location of a reference plane. This reference plane can be offset from the location of the tomographic planes.

(3) If a mechanism using a light source is used to satisfy 6.9.2.2(1) or 6.9.2.2(2), the light source shall allow visualizing the location of the tomographic plane or reference plane under ambient light conditions of up to 500 lux (46 foot candles).

6.9.2.3 Beam-On and Shutter Status Indicators and Control Switches.

(1) The CT x-ray control and gantry shall provide visual indication whenever x-rays are produced and, if applicable, whether the shutter is open or closed.

(2) Each emergency button or switch shall be clearly labeled as to its function.

6.9.2.4 Patient Communication.

(1) Provision shall be made for two-way aural communication between the patient and the operator at the control panel.

(2) Windows, mirrors, closed-circuit television, or an equivalent shall be provided to permit continuous observation of the patient during irradiation and shall be so located that the operator can observe the patient from the control panel.

(3) When the primary viewing system is by electronic means, an alternate viewing system (which may be electronic) shall be available for use in the event of failure of the primary viewing system.

(4) Patient scanning shall be allowed only when a viewing system is available and in use.

6.9.3 Each computed tomography facility shall have the following operating procedures and radiation exposure controls.

6.9.3.1 Console Performance.

(1) The operator of the CT x-ray system shall meet the minimum operator requirements of these regulations and be specifically trained on the operational features of the unit by a manufacturer's application specialist, RMP, or someone deemed as a qualified trainer.

(2) The following information shall be readily available to the CT operator:

(a) Instructions on performing routine QC, including the use of the CT phantom(s), a schedule of routine QC appropriate for the system, allowable variations set by the RMP for the indicated parameters, and the results of at least the most recent routine QC completed on the system;

(b) Scanning protocols reviewed and approved by the RPC, including instructions on reporting deviations.

(3) If the RMP evaluation or routine QC of the CT x-ray system identifies that a system operating parameter has exceeded a tolerance established by the RMP, use of the CT x-ray system on patients shall be limited to those uses permitted by established written instructions of the RMP.

6.9.3.2 Indication of CT Conditions of Operation.

(1) The CT x-ray system shall be designed such that the CT conditions of operation to be used during a scan or a scan sequence shall be indicated prior to the initiation of a scan or a scan sequence.

(2) On equipment having all or some of these conditions of operation at fixed values, this requirement may be met by permanent markings.

(3) Indication of CT conditions of operation shall be visible from any position from which scan initiation is possible.

6.9.3.3 CT Radiation Protocol Committee (RPC)

The requirements of 6.9.3.3 and other requirements associated with a Radiation Protocol Committee shall become effective on or after January 1, 2022.

The registrant shall develop and maintain an RPC in accordance with the following:

(1) Members of the RPC.

(a) Members of the RPC shall include but not be limited to the:

(i) Lead CT radiologist;

(ii) Lead CT technologist;

(iii) RMP; and

(iv) Other individuals as deemed necessary by the registrant (e.g., Radiation Safety Officer, Chief Medical or Administrative Officer, Radiology Department Administrator or Manager).

(b) If the registrant has more than one site with CT, they may establish a system-wide RPC.

(c) Two or more registrants may form a cooperative RPC as long as each facility has a representative on the committee.

(d) If the registrant has already established a radiation safety committee, the requirements of 6.9.3.3 may be delegated to that committee if the members meet the requirements of 6.9.3.3(1).

(2) Responsibilities.

(a) The registrant shall:

(i) Review existing CT protocols, taking into consideration the capabilities and diagnostic tasks of the system, along with the evaluation and implementation of new and innovative technologies that can improve image quality and/or lower patient dose in comparison with the older protocol.

(ii) Determine and review the protocols used frequently or that could result in significant doses. The review shall include acquisition and reconstruction parameters, image quality, and radiation dose. At a minimum, the facility shall review the following clinical protocols, if performed, at intervals not to exceed 12 months:

(1) Pediatric Head;

(2) Pediatric Abdomen;

(3) Adult Head;

(4) Adult Abdomen;

(5) Adult Chest;

(6) Brain Perfusion.

(iii) Establish and implement written protocols, or protocols documented in an electronic recordkeeping system, that include but are not limited to the following:

(1) A method to be used to monitor the CT radiation output (dose indices).

(2) To the extent possible, a standardized protocol naming process.

(3) A notification value and alert value for CT protocols reviewed in 6.9.3.3(2)(a)(ii). Notification and alert values may be applied by using trigger values in conformance with nationally accepted standards or facility established values and procedures as defined by the RMP.

(4) Actions to be taken when the notification or alert value is exceeded.

(5) A process determining who has access and authority to make changes to the protocol management systems, including a method to prevent inadvertent or unauthorized modifications to a CT protocol.

(iv) The RPC shall review and approve protocols developed or modified under 6.9.3.3(2)(a)(iii).

(v) If CT fluoroscopy is performed, the registrant shall establish and implement operating procedures and training designed to minimize patient and occupational radiation exposure.

(vi) Provide an annual report summarizing the details and activities of the RPC to the radiation safety committee or radiation safety officer, in the absence of a radiation safety committee.

(vii) At a minimum the RPC members in 6.9.3.3(1)(a)(i) through (iii) shall meet as often as necessary to conduct business but at intervals not to exceed 12 months.

(3) Records

(a) A record of each RPC meeting shall be maintained. The record shall include the date, names of individuals in attendance, minutes of the meeting, and any action taken.

(b) The registrant shall maintain a record of RPC policies and procedures.

(c) The registrant shall maintain a record of radiation output (dose indices) information so the radiation dose may be estimated in accordance with established protocols (e.g., SSDE). The record shall include:

(i) Patient identification;

(ii) Type and date of examination;

(iii) Identification of the CT system used;

(iv) The dose values the CT system provides (e.g., Dose-Length Product, SSDE); and

(v) Any change to the established protocol for the specific patient.

(d) Records required by this section shall be retained for inspection by the department for a period of 3 years following the date of the record.

6.9.3.4 CT systems used in treatment planning.

CT systems solely used for treatment planning in radiation oncology shall meet the requirements in Part 24.9 of these regulations.

6.9.3.5 PET CT and SPECT CT Systems

CT systems solely used for localization and calculation of attenuation coefficients in nuclear medicine studies shall meet the requirements in Sections 6.9.1, 6.9.2.4, 6.9.3.1, 6.9.3.3, and 6.9.4.1 unless otherwise exempted below:

(1) In lieu of 6.9.4.2, a RMP shall complete a certification evaluation on the CT system following nationally recognized guidelines or those of the manufacturer at intervals not to exceed 12 months.

(2) In lieu of 6.9.4.3, routine QC checks shall be completed at intervals not to exceed 1 week. These checks shall be established and documented by a RMP following nationally recognized guidelines or those of the manufacturer.

(3) 6.9.3.1(2)(b) (RPC)

6.9.3.6 Veterinary CT Systems.

CT systems, including CBCT systems, solely used in non-human imaging shall meet the requirements of 6.9.4.1(1) (area radiation surveys) and are otherwise exempt from the standards of Section 6.9.

6.9.3.7 Cone Beam Computed Tomography Systems.

(1) CBCT facilities shall meet the following requirements, as applicable:

(a) Excluding veterinary imaging systems the minimum source-skin distance for CBCT imaging systems shall be consistent with the applicable requirements in 21 CFR subchapter J;

(b) 6.4;

(c) 6.6.3.1, 6.6.3.2, 6.6.3.4(1), and 6.8.2.1(4); and

(d) 6.9.1.3, 6.9.2.1, 6.9.2.3, 6.9.3.2, and 6.9.3.8 as applicable.

(2) Beam alignment.

(a) The x-ray field in the plane of the image receptor shall not exceed beyond the edge of the image receptor by more than 2 percent of the SID, when the axis of the x-ray beam is perpendicular to the plane of the image receptor.

(b) In addition, the center of the x-ray field shall be aligned with the center of the image receptor to within 2 percent of the SID.

(3) A certification evaluation shall be performed by, or under the direct supervision of a RMP.

(a) The evaluation shall follow nationally recognized standards and tolerances or those recognized by the Agency.

(b) The evaluation shall be performed in accordance with Part 2, Section 2.5.1.

(c) The facility shall maintain documentation of the established standards and tolerances and certification evaluation results.

(4) The registrant shall follow the QC recommendations provided by the CBCT manufacturer.

(a) In the absence of manufacturer provided QC recommendations, the registrant shall implement and document QC guidelines established by a RMP in accordance to nationally recognized guidelines or those recognized by the Agency.

(5) The registrant or RPC, if established, shall implement and document a policy addressing deviations from established protocols.

(6) The CBCT x-ray system shall only be operated by an individual who has been specifically trained in its operation.

(7) The following information shall be readily available to the CBCT operator:

(a) Instructions on performing routine QC, including the use of the CBCT phantom(s), a schedule of routine QC appropriate for the system, allowable variations set by the RMP, if required, for the indicated parameters, and the results of at least the most recent routine QC completed on the system.

(8) Exemption.

(a) The registrant using fluoroscopy systems capable of CBCT shall meet the applicable requirements of 6.9.3.7 excluding 6.9.3.7(1)(d).

6.9.3.8 Additional Requirements Applicable to CT X-Ray Systems Containing a Gantry Manufactured After September 3, 1985.

(1) The total error in the indicated location of the tomographic plane or reference plane shall not exceed 5 millimeters.

(2) If the x-ray production period is less than one-half second, the indication of x-ray production shall be actuated for at least one-half second. Indicators at or near the gantry shall be discernible from any point external to the patient opening where insertion of any part of the human body into the primary beam is possible.

(3) The deviation of indicated scan increment versus actual increment shall not exceed plus or minus 2 millimeter with any mass from 0 to 100 kg resting on the support device.

(a) The patient support device shall be incremented from a typical starting position to the maximum incremented distance, the manufacturer's specified distance, or 30 cm, whichever is less, and then returned to the starting position.

(b) Measurement of actual versus indicated scan increment may be taken anywhere along this travel.

(c) When table increment is not the primary means of slice position location, the registered medical physicist may provide for prior written Department review and approval alternative measurement procedures to determine the accuracy of slice position.

(4) Premature termination of the x-ray exposure by the operator shall necessitate resetting of the CT conditions of operation prior to the initiation of another scan.

CT surveys, certification evaluations, routine QC, and operating procedures

6.9.4 Each computed tomography facility shall conduct required surveys, certification evaluations, and routine QC.

6.9.4.1 Radiation Protection Evaluations.

(1) An area radiation survey or measurement shall be made by, or under the direct supervision of, a registered medical physicist or QE, to verify and document compliance with Part 4, Section 4.14 and 4.15 under the following conditions:

(a) All CT x-ray systems installed shall have an area radiation survey or measurement completed by, or under the direct supervision of, the RMP or QE within 90 days of installation;

(b) Any change in the facility or equipment that might cause a significant increase in radiation hazard; or

(c) Upon first use of a portable or mobile CT imaging system, consistent with the applicable requirements of 6.3.2.4.

(d) The registrant shall obtain from the registered medical physicist, a written report of the measurements required by 6.9.4.1, and a copy of the report shall be made available to the Department upon request.

6.9.4.2 CT System performance evaluations.

(1) The testing of the CT x-ray system shall be performed by, or under the personal supervision of, an RMP who assumes responsibility and signs the final performance testing and certification evaluation report.

(2) Evaluation standards and tolerances shall be established by the registered medical physicist and maintained by the facility. The standards and tolerances shall be:

(a) In accordance with protocols published by nationally recognized organizations (for example, AAPM Report 96), unless the registered medical physicist determines that a particular recommendation of such report is not warranted for the clinical tasks for which the equipment will be used;

(3) The certification evaluation for a CT x-ray system shall be performed by or under the personal supervision of an RMP in accordance with Part 2, Section 2.5.1.

(a) Initial installation or acceptance testing; or

(b) Any change or service that could cause a change in the radiation output (dose indices) or image quality.

(4) The evaluation shall include but not be limited to:

(a) Geometric factors and alignment including:

(i) Alignment light accuracy;

(ii) Table increment accuracy.

(b) Image localization from scanned projection radiograph (localization image);

(c) Radiation beam width;

(d) Image quality including:

(i) High-contrast (spatial) resolution;

(ii) Low-contrast resolution;

(iii) Image uniformity;

(iv) Noise;

(v) Artifact evaluation.

(e) CT number accuracy;

(f) Image quality for acquisition workstation display devices;

(g) A review of the results of the routine QC;

(h) A safety evaluation of audible and visual signals, and posting requirements;

(i) Dosimetry.

(5) The measurement of the radiation output (dose indices) of a CT x-ray system shall be performed with a calibrated dosimetry system. The calibration of such system hall be traceable to a national standard. The dosimetry system shall have been calibrated within the preceding 2 years.

6.9.4.3 Routine quality control.

A routine QC program on the CT system shall:

(1) Be developed by a registered medical physicist and include acceptable tolerances for points evaluated;

(2) Incorporate the use of a water equivalent phantom. At a minimum, noise, CT number, and artifacts shall be evaluated.

(3) Be completed at time intervals and under system conditions specified by a registered medical physicist. The interval shall not exceed 1 week.

(4) Be documented and maintained for inspection by the Department for a period of 3 years following the date of the record.

6 CCR 1007-1-6.9

Colorado Register, Vol 37, No. 14. July 25, 2014, effective 8/14/2014

38 CR 02, January 25, 2015, effective 2/14/2015

38 CR 05, March 10, 2015, effective 3/30/2015

38 CR 12, June 25, 2015, effective 7/15/2015

38 CR 14, July 25, 2015, effective 8/14/2015

39 CR 02, January 25, 2016, effective 2/14/2016

39 CR 16, August 25, 2016, effective 9/14/2016

39 CR 22, November 25, 2016, effective 12/15/2016

40 CR 11, June 10, 2017, effective 6/30/2017

40 CR 20, October 25, 2017, effective 11/14/2017

42 CR 24, December 25, 2019, effective 1/14/2020

43 CR 14, July 25, 2020, effective 8/14/2020

43 CR 18, September 25, 2020, effective 10/15/2020

44 CR 11, June 10, 2021, effective 7/15/2021

44 CR 14, July 25, 2021, effective 8/14/2021

45 CR 22, November 25, 2022, effective 12/15/2022

47 CR 06, March 25, 2024, effective 4/14/2024