16 Del. Admin. Code § 4465-F-11.0

Current through Register Vol. 28, No. 7, January 1, 2025

Section 4465-F-11.0 - Computed Tomography Equipment

11.1 Requirements for CT Equipment.

11.1.1 Accreditation. All stationary diagnostic CT x-ray systems for human use should be accredited by a nationally recognized accrediting organization.

11.1.2 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.

11.1.3 Termination of Exposure.

11.1.3.1 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 110 percent of its preset value through the use of either a backup timer or devices which monitor equipment function. (21CFR 1020.33(f)(2)(i))

11.1.3.2 A visible signal shall indicate when the x-ray exposure has been terminated through the means required by Part F, subsection 11.1.3.1. (21CFR 1020.33(f)(2)(i))

11.1.3.3 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. (first part of 21CFR 1020.33(f)(2)(ii))

11.1.4 Tomographic Plane Indication and Alignment.

11.1.4.1 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. (21CFR 1020.33(g)(1))

11.1.4.2 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. (version of 21CFR 1020.33(g)(2))

11.1.4.3 If a mechanism using a light source is used to satisfy the requirements of Part F, subsection 11.1.4.1 or Part F, subsection 11.1.4.2, the light source shall allow visual determination of the location of the tomographic plane or reference plane under ambient light conditions of up to 500 lux. (21CFR 1020.33(g)(5))

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

11.1.5.1 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. (First part of 21CFR 1020.33(h)(1))

11.1.5.2 Each emergency button or switch shall be clearly labeled as to its function.

11.1.6 Indication of CT Conditions of Operation.

11.1.6.1 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. 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. (21CFR 1020.33(f))

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

11.1.7.1 The total error in the indicated location of the tomographic plane or reference plane shall not exceed 5 millimeters. (21CFR 1020.33(g)(3))

11.1.7.2 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. (second part of 21CFR 1020.33(h)(1))

11.1.7.3 The deviation of indicated scan increment versus actual increment shall not exceed plus or minus 1 millimeter with any mass from 0 to 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 30 centimeters, whichever is less, and then returned to the starting position. Measurement of actual versus indicated scan increment may be taken anywhere along this travel. (21CFR 1020.33(i))

11.1.7.4 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. (second part of 21CFR 1020.33(f)(2)(ii)

11.2 CT Facility Design Requirements.

11.2.1 Aural Communication. Provision shall be made for two-way aural communication between the patient and the operator at the control panel.

11.2.2 Viewing Systems.

11.2.2.1 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.

11.2.2.2 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.

11.3 CT Surveys, Performance Evaluations, Routine QC, and Operating Procedures.

11.3.1 Radiation Protection Surveys.

11.3.1.1 All CT x-ray systems installed after the effective date of these regulations shall have a radiation protection survey completed by, or under the direct supervision of, the QMP prior to clinical use. Existing systems not previously surveyed shall have a survey made by, or under the direct supervision of, a QMP within 12 months after the effective date of these regulations. In addition, such surveys shall be done after any change in the facility or equipment which might cause a significant increase in radiation hazard.

11.3.1.2 The registrant shall obtain a written report of the survey from the QMP (QE), and a copy of the report shall be made available to the Agency upon request.

11.3.2 System Performance Evaluations.

11.3.2.1 The annual testing of the CT x-ray system shall be performed by, or under the personal supervision of, a QMP who assumes the responsibility and signs the final performance evaluation report.

11.3.2.2 Evaluation standards and tolerances shall be established by the QMP (QE) and maintained by the facility. These standards and tolerances shall meet nationally recognized standards and tolerances for the CT x-ray system.

11.3.2.3 The evaluation of a CT x-ray system shall be performed after initial installation, and at least annually thereafter. In addition, the QMP shall complete an evaluation of the CT system prior to clinical use, after any change or replacement of components which, in the opinion of the QMP, could cause a change in the radiation output or image quality.

11.3.2.4 The evaluation shall include but not be limited to:

11.3.2.4.1 Geometric factors and alignment including:

11.3.2.4.1.1 Alignment light accuracy;

11.3.2.4.1.2 Table increment accuracy.

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

11.3.2.4.3 Radiation beam width;

11.3.2.4.4 Image quality including:

11.3.2.4.4.1 High-contrast (spatial) resolution;

11.3.2.4.4.2 Low-contrast resolution;

11.3.2.4.4.3 Image uniformity;

11.3.2.4.4.4 Noise;

11.3.2.4.5 Artifact evaluation.

11.3.2.4.6 CT number accuracy;

11.3.2.4.7 Image quality for acquisition workstation display devices;

11.3.2.4.8 A review of the results of the routine QC required under Part F, subsection 11.1.3;

11.3.2.4.9 A safety evaluation of audible and visual signals, posting requirements;

11.3.2.4.10 Dosimetry.

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

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

11.3.3.1 Be developed by a QMP (QE) and include acceptable tolerances for points evaluated;

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

11.3.3.3 Be completed at time intervals and under system conditions specified by the QMP (QE). The interval shall not to exceed 1 week.

11.3.3.4 Be documented and maintained for inspection by the Agency.

11.3.4 Operating Procedures.

11.3.4.1 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 applications specialist, and/or QMP.

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

11.3.4.2.1 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 QMP (QE) for the indicated parameters, and the results of at least the most recent routine QC completed on the system; and

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

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

11.4 Radiation Protocol Committee (RPC). The registrant shall develop and maintain an RPC in accordance with the following:

11.4.1 Members of the RPC.

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

11.4.1.1.1 Radiologist;

11.4.1.1.2 CT Technologist;

11.4.1.1.3 QMP or QE; and

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

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

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

11.4.4 If the registrant has already established a radiation safety or Radiation Protocol Committee (RPC), the requirements of this subsection may be delegated to that committee if the members meet the requirements of Part F, subsection 11.4.1.

11.4.5 Responsibilities of the RPC. The RPC shall:

11.4.5.1 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.

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

11.4.5.3 Determine and review the protocols 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 least annually:

11.4.5.3.1 Pediatric Head;

11.4.5.3.2 Pediatric Abdomen;

11.4.5.3.3 Adult Head;

11.4.5.3.4 Adult Abdomen;

11.4.5.3.5 Adult Chest;

11.4.5.3.6 Brain Perfusion.

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

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

11.4.5.4.2 A standardized protocol naming policy.

11.4.5.4.3 A DRL, notification value, and alert value for CT procedures reviewed in Part F, subsection 11.4.5.3. 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 QMP.

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

11.4.5.4.5 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.

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

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

11.4.5.7 At a minimum the RPC members in Part F, subsection 11.4.1.1 shall meet as often as necessary to conduct business but at intervals not to exceed 12 months.

11.4.6 Records.

11.4.6.1 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, for at least three years.

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

11.4.6.3 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:

11.4.6.3.1 Patient identification;

11.4.6.3.2 Type and date of examination;

11.4.6.3.3 Identification of the CT system used; and

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

11.5 CT systems used in treatment planning. CT systems solely used for treatment planning in radiation oncology shall meet the requirements in Part X, subsection 10.0 of these regulations.

11.6 PET CT and SPECT CT Systems. CT systems solely used to calculate attenuation coefficients in nuclear medicine studies shall meet the requirements in Part F, subsection 11.1 through Part F, subsection 11.4 unless otherwise exempted below:

11.6.1 Part F, subsection 11.1.1 (Accreditation)

11.6.2 In lieu of Part F, subsection 11.3.2, a QMP shall complete a performance evaluation on the CT system following nationally recognized guidelines at intervals not to exceed 12 months.

11.6.3 In lieu of Part F, subsection 11.3.3, routine QC checks shall be completed at intervals not to exceed 1 week. These checks shall be established and documented by a QMP following nationally recognized guidelines.

11.6.4 Part F, subsection 11.3.4.2.2 (RPC)

11.7 Veterinary CT Systems. CT systems, including CBCT systems, solely used in non-human imaging shall meet the requirements of Part F, subsection 11.3.1 (radiation protection surveys) and are otherwise exempt from the standards of Part F, subsection 11.0.

11.8 Cone Beam Computed Tomography Systems.

11.8.1 CBCT facilities shall meet Part F, Section 4.0, Part F, subsection 6.1 and 6.11, and Part F, subsection 11.1.2 through Part F, subsection 11.1.7, as applicable.

11.8.2 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 2 percent 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 2 percent of the SID.

11.8.3 A performance evaluation shall be performed by, or under the direct supervision of, a QMP. The evaluation shall follow nationally recognized standards and tolerances. The evaluation shall be performed within 30 days of initial installation and least annually, and prior to clinical use, after any change or replacement of components which, in the opinion of the QMP, could cause a change in the radiation output or image quality. The facility shall maintain documentation of the established standards and tolerances and testing results for at least three years.

11.8.4 The registrant shall follow the QC recommendations provided by the CBCT manufacturer. In the absence of manufacturer provided QC recommendations, the registrant shall implement and document QC guidelines established by a QMP in accordance with nationally recognized guidelines.

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

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

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

11.8.7.1 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 QMP (QE), if required, for the indicated parameters, and the results of at least the most recent routine QC completed on the system.

11.8.8 Exemption. A QMP performance evaluation on CBCT systems capable of operating at no greater than 100 kV or 20 mA shall be performed at least every two years.

11.8.9 Exemption. The registrant using fluoroscopy systems capable of CBCT shall meet Part F 11.8, except Part F, subsection 11.1.2 through Part F, subsection 11.1.7 and Part F, subsection 11.8.1.

16 Del. Admin. Code § 4465-F-11.0

16 DE Reg. 1274(6/1/2013)
22 DE Reg. 401( 11/1/2018) (Final)