CT Tube Replacement & Calibration Service in Rwanda
Engineering Excellence & Technical Support

• Warm-up Routine: Gradually increasing the tube voltage and current to reach stable operating temperature.

• kVp and mA Calibration: Verifying and adjusting the accuracy of the X-ray tube voltage (kVp) and tube current (mA) settings. This ensures consistent radiation output.

• Beam Filtration Adjustment: Calibrating the inherent and added filtration to achieve the desired beam spectrum and reduce patient dose.

• Collimator Alignment: Ensuring the X-ray beam is properly aligned with the detector array and collimators.

• CT Number (Hounsfield Unit) Calibration: Using phantoms to verify the accuracy of CT numbers for various materials (e.g., water, bone), ensuring proper tissue characterization.

• Image Quality Assessment: Performing scans with specific phantoms to evaluate spatial resolution, low-contrast detectability, noise levels, and artifact reduction.

• Dose Optimization: Adjusting parameters to achieve optimal image quality at the lowest possible radiation dose to the patient, adhering to ALARA (As Low As Reasonably Achievable) principles.

• Customer Contact: The process begins with a customer (hospital, clinic, imaging center) contacting the service provider (e.g., a biomedical engineering company or manufacturer's representative) with a request for CT tube replacement and/or calibration.

• Information Gathering: The service provider gathers essential details, including the CT scanner make and model, the existing tube's serial number, the nature of the problem (e.g., performance degradation, complete failure, scheduled replacement), and the desired service timeframe.

• Preliminary Assessment & Quotation: Based on the gathered information, a preliminary assessment is made. A detailed quotation is prepared, outlining the cost of the new tube (if applicable), labor, travel expenses, and any associated consumables. This quotation also specifies the estimated timeline for the service.

• Agreement & Scheduling: Upon customer acceptance of the quotation and terms, a service agreement is signed. The service visit is then scheduled, taking into account the availability of the customer's equipment, the service team, and the necessary parts.

• Tube Procurement (if replacement): If a tube replacement is required, the new CT tube is ordered from the manufacturer or authorized distributor. This step includes verifying compatibility with the specific CT scanner model.

• Logistics & Travel Arrangements: The service team's travel to Rwanda is arranged, including flights, accommodation, and local transportation. Necessary permits or visas are secured if required.

• Tooling & Equipment Check: All specialized tools, diagnostic equipment, safety gear, and calibration instruments required for the service are checked and prepared.

• Pre-Service Communication: A reminder and confirmation of the scheduled service date, time, and required site access are communicated to the customer.

• Site Arrival & Safety Briefing: The service team arrives at the customer's facility. A brief safety orientation is conducted with the site personnel to ensure awareness of any specific site hazards and protocols.

• CT Scanner Assessment: The CT scanner is thoroughly inspected to confirm the reported issue and to identify any other potential problems that might affect the service.

• Tube Removal (if replacement): If a tube replacement is part of the service, the old CT tube is carefully disconnected and removed following manufacturer-specific procedures and safety guidelines.

• New Tube Installation (if replacement): The new CT tube is installed, ensuring proper alignment, connections, and secure mounting.

• Initial System Power-Up & Diagnostics: The CT scanner is powered on with the new or re-installed tube. Initial diagnostic tests are performed to verify basic functionality and to detect any immediate errors.

• Tube Calibration:

* **Geometric Calibration:** This involves adjusting parameters related to the physical alignment and positioning of the X-ray tube and detector to ensure accurate image geometry.

* **Photometric Calibration:** This process optimizes the X-ray output (kVp, mA, exposure time) and detector sensitivity to ensure consistent image quality and dose accuracy.

* **Image Quality Testing:** A series of phantom scans are performed to evaluate image resolution, contrast, noise, and artifacts. These results are compared against manufacturer specifications.

• Functional Testing: All CT scanning modes and features are tested to confirm their operational status and performance.

• Final Image Quality Assessment: Representative clinical or phantom images are reviewed with the customer's radiologist or lead technologist to confirm satisfactory image quality and performance.

• Service Report Generation: A comprehensive service report is compiled. This report includes details of the work performed, the original and final calibration parameters, diagnostic test results, parts replaced, time spent, and any recommendations.

• Customer Sign-Off: The customer's authorized representative reviews and signs the service report, acknowledging the completion of the service.

• Final Invoicing: The invoice is generated based on the agreed-upon quotation and the actual services rendered, as documented in the service report.

• Performance Monitoring: The service provider may offer remote monitoring or scheduled follow-up calls to ensure the continued optimal performance of the CT scanner.

• Warranty & Support: Information on the warranty for the replaced tube and the service provided is communicated to the customer.

• Future Service Planning: Recommendations for future maintenance or potential issues are provided, helping the customer plan for long-term equipment reliability.