216 R.I. Code R. 216-RICR-40-20-4.7

Current through October 15, 2024

Section 216-RICR-40-20-4.7 - Computed Tomography Equipment

4.7.1Requirements for CT Equipment

A. Applicability. X-ray systems subject to § 4.7 of this Part shall also meet the applicable requirements of § 4.4 of this Part. Unless otherwise specified, the requirements for equipment contained in §4.7.1 of this Part are applicable to CT X-ray systems manufactured or remanufactured on or after September 3, 1985.

1. Accreditation. All diagnostic CT X-ray equipment for human use shall be accredited by an accrediting organization recognized by the Agency unless otherwise authorized by the Agency.

2. Technical and Safety Information. 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.

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

2. A visible signal shall indicate when the X-ray exposure has been terminated through the means required by §4.7.1(B) of this Part.

3. The operator shall be able to terminate the X-ray exposure at any time during a scan, or series of scans under CT system control, of greater than one half (0.5) second duration.

C. 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 §§4.7.1(C)(1) or (2) of this Part, the light source shall provide illumination levels sufficient to permit visual determination of the location of the tomographic plane or reference plane under ambient light conditions of up to five hundred (500) lux.

D. 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.

E. Indication of CT Conditions of Operation. 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 scan sequence. On equipment having all or some of these conditions of operation at fixed values, this requirement may be met by permanent markings. Indication of CT conditions of operation shall be visible from any position from which scan initiation is possible.

F. Additional Requirements Applicable to CT X-Ray Systems Containing a Gantry

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

2. If the X-ray production period is less than one half (0.5) second, the indication of X-ray production shall be actuated for at least one half (0.5) 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 one millimeter (± 1 mm) with any mass from zero (0) to one hundred (100) kilograms resting on the support device. The patient support device shall be incremented from a typical starting position to the maximum incremented distance or thirty centimeters (30 cm), whichever is less, and then returned to the starting position. Measurement of actual versus indicated scan increment may be taken anywhere along this travel.

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.

4.7.2CT Facility Design Requirements

A. Aural Communication. Provision shall be made for two (2) way aural communication between the patient and the operator at the control panel.

B. Viewing Systems

1. 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.

2. 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.

4.7.3Radiation Protection Survey, Routine Quality Control, and Operating Procedures

A. Radiation Protection Survey

1. All CT X-ray systems shall have a radiation protection survey completed by, or under the direct supervision of, a Qualified Medical Physicist within thirty (30) days of installation. In addition, such surveys shall be done after any change in the facility or equipment which might cause a significant increase in radiation hazard.

2. The registrant shall obtain a written report of the survey from the Qualified Medical Physicist, and a copy of the report shall be made available to the Agency upon request.

B. Routine Quality Control. A routine QC program on the CT system shall:

1. Be developed by a Qualified 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 the Qualified Medical Physicist. The interval shall not exceed one (1) week.

4. The registrant shall maintain a record of each routine QC check required by §4.7.3(B) of this Part for three (3) years.

C. Operating Procedures

1. The CT X-ray system shall not be operated except by an individual who has been specifically trained on the operational features of the unit by a manufacturer's applications specialist, Qualified Medical Physicist, or someone deemed qualified by the Agency.

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

a. The results of at least the most recent routine QC completed on the system:

b. Instructions on performing routine QC, including the use of the CT phantom(s), a schedule of routine QC appropriate for the system, and allowable variations set by the Qualified Medical Physicist for the indicated parameters; and

c. Scanning protocols established by the RPC, including instructions on reporting deviations.

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

4.7.4CT X-ray System Used for Treatment Planning in Radiation Oncology

A. A CT X-ray system used solely for treatment planning in radiation oncology is exempt from the specific requirements of §§4.7.1, 4.7.2, and 4.7.3 of this Part, and is only subject to the requirements of § 5.10 of this Subchapter.

B. A CT X-ray system used for both diagnostic X-ray and radiation therapy simulation is subject to the requirements of both § 4.7 of this Part and § 5.10 of this Subchapter.

4.7.5CT Radiation Protocol Committee (RPC)

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

1. Members of the RPC shall include but not be limited to the:

a. Lead CT radiologist;

b. Lead CT technologist;

c. Qualified Medical Physicist; and

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

2. If the registrant has more than one (1) site with CT, the registrant may establish a system-wide RPC.

3. Two (2) or more registrants may form a cooperative RPC as long as each facility has a representative on the committee.

4. If the registrant has already established a radiation safety committee, the requirements of §4.7.5 of this Part may be delegated to that committee if the members meet the requirements of §4.7.5(A)(1) of this Part.

B. Responsibilities of the RPC. The RPC shall:

1. Review existing CT protocols 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.

2. Review the capabilities of the individual CT scanner to ensure maximum performance is achieved

3. Determine and review the protocols that are used frequently or could result in significant doses. This 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 twelve (12) months:

a. Pediatric Head;

b. Pediatric Abdomen;

c. Adult Head;

d. Adult Abdomen;

e. Adult Chest; and

f. Brain Perfusion.

4. Establish and implement written protocols, or protocols documented in an electronic reporting system, that include but are not limited to the following:

a. A method to be used to monitor the CT radiation output.

b. A standardized protocol naming policy.

c. A DRL, notification value, and alert value for CT procedures reviewed in §4.7.5(B)(3) of this Part. Notification and alert values may be applied by using trigger values in conformance with NEMA XR-29 or facility-established values and procedures as defined by the Qualified Medical Physicist.

d. Actions to be taken for cases when the dose alert value was exceeded which may include patient follow-up.

e. 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.

5. If CT fluoroscopy is performed, the RPC shall establish and implement operating procedures and training designed to minimize patient and occupational radiation exposure.

6. Provide an annual report to the radiation safety committee or radiation safety officer, in the absence of a radiation safety committee,

7. At a minimum the RPC members in §§4.7.5(A)(1)(a) through (c) of this Part shall meet as often as necessary to conduct business but at intervals not to exceed twelve (12) months.

C. Records

1. 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.

2. The registrant shall maintain a record of RPC policies and procedures.

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

a. Patient identification;

b. Type and date of examination;

c. Identification of the CT system used; and

d. The dose values the CT system provides (e.g., CTDIvol, DLP, SSDE).

4.7.6PET CT and SPECT CT System

A. A CT X-ray system used solely to calculate attenuation coefficients in nuclear medicine studies shall meet the applicable requirements in §§4.7.1, 4.7.2, 4.7.3, 4.7.5 and 4.10.1 of this Part unless otherwise exempted below:

1. §4.7.1(A)(1) of this Part - Accreditation

2. In lieu of §4.10.1(A)(5) of this Part, a Qualified Medical Physicist shall complete a performance evaluation on the CT system following nationally recognized guidelines or those approved by the Agency at intervals not to exceed twelve (12) months.

3. In lieu of §4.7.1(B) of this Part, routine QC checks shall be completed at intervals not to exceed one (1) week. These checks shall be established and documented by a Qualified Medical Physicist following nationally recognized guidelines or those approved by the Agency.

4. §4.7.3(C)(2)(c) of this Part - Scanning protocols established by the RPC.

4.7.7Veterinary CT System

A CT X-ray system, including a cone beam computed tomography system (CBCT), used solely in non-human imaging shall meet the requirements of §4.7.3(A) of this Part [radiation protection surveys] and is otherwise exempt from the standards of § 4.7 of this Part.

4.7.8Cone Beam Computed Tomography System (CBCT)

A. A CBCT facility shall meet §§ 4.4, 4.6.2, 4.6.5, 4.7.1(A)(2), and 4.7.1(B), (C), (D), and (E) of this Part, as applicable.

1. Exemption. A registrant using fluoroscopy systems capable of CBCT shall meet §4.7.8 of this Part except §§4.7.1(A)(2), and 4.7.1(B), (C), (D), and (E) of this Part.

B. Beam Alignment. The X-ray field in the plane of the image receptor shall not exceed beyond the edge of the image receptor by more than two percent (2%) of the 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 shall be aligned with the center of the image receptor to within two percent (2%) of the SID.

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

D. A CBCT X-ray system shall only be operated by an individual who has been specifically trained in its operation.

E. The following information shall be readily available to the CBCT operator:

1. Instructions on performing routine QC, including the use of the CBCT phantom(s);

2. A schedule of routine QC appropriate for the system;

3. Allowable variations set by the Qualified Medical Physicist, if required, for the indicated parameters; and

4. The results of at least the most recent routine QC completed on the system.

216 R.I. Code R. 216-RICR-40-20-4.7

Adopted effective 1/1/2019
Amended effective 5/25/2022
Amended effective 11/28/2023