Radiotherapy and Chemotherapy Equipment: Principles, Operation, and Maintenance
1. Radiotherapy Equipment
Radiotherapy uses high-energy radiation to destroy cancer cells. The main equipment includes Linear Accelerators (LINAC), Cobalt-60 units, and other radiation sources such as brachytherapy seeds.
1.1 Linear Accelerators (LINAC)
A Linear Accelerator (LINAC) is the most common radiotherapy machine. It delivers high-energy X-rays or electrons to a tumor while sparing surrounding tissues.
(A labeled diagram showing the main components of a LINAC: electron gun, waveguide, bending magnet, and treatment head.)
Principles of Operation
- Electrons are generated and accelerated through a waveguide.
- A bending magnet directs the electrons toward the target.
- Electrons either hit a target to produce X-rays or are used directly for electron therapy.
- The X-rays are shaped to match the tumor using a multi-leaf collimator (MLC).
Maintenance
- Daily checks: Beam quality, alignment, and mechanical parts.
- Monthly servicing: Dosimetry calibration and safety tests.
- Annual checks: Full system evaluation by medical physicists.
1.2 Cobalt-60 Units
Cobalt-60 machines use gamma rays from radioactive cobalt for deep tumor treatment.
(A labeled diagram showing the source capsule, collimators, and shielding.)
Principles of Operation
- Cobalt-60 decays to produce 1.17 MeV and 1.33 MeV gamma rays.
- The radiation beam is collimated to focus on the tumor.
- The machine rotates to deliver doses from multiple angles.
Maintenance
- Source replacement every 5–7 years (due to decay).
- Radiation shielding checks to prevent leakage.
- Collimator and field size verification for precise treatment.
1.3 Other Radiation Sources
| Type | Example | Application |
| Brachytherapy | Iridium-192, Cesium-137 | Internal radiation for prostate and cervical cancer |
| Proton Therapy | Proton beams | Precision treatment for brain and pediatric cancers |
| Gamma Knife | Cobalt-60 array | Brain tumor radiosurgery |
2. Chemotherapy Equipment
Chemotherapy delivers drugs to kill cancer cells. Equipment includes infusion pumps and safe handling systems to protect healthcare workers.
2.1 Infusion Pumps
Infusion pumps control chemotherapy drug delivery at a precise rate.
Image: Chemotherapy Infusion Pump Setup
(A diagram showing an infusion pump connected to an IV line and a patient.)
Types of Infusion Pumps
- Volumetric Pumps – Deliver fixed amounts over time.
- Syringe Pumps – Used for small doses.
- Elastomeric Pumps – Portable devices for home chemotherapy.
Maintenance
- Daily checks: Battery status, tubing integrity.
- Calibration: Ensures accurate drug flow rate.
- Cleaning: Prevents contamination and drug residue buildup.
2.2 Safe Handling Procedures
Chemotherapy drugs are toxic and require strict handling protocols.
Key Safety Measures
- Use of biosafety cabinets for drug preparation.
- Closed-system transfer devices (CSTDs) to prevent leaks.
- Protective gear (gloves, gowns, masks) for healthcare workers.
- Proper disposal of chemotherapy waste in hazardous material bins.
3. Principles of Operation and Maintenance
| Equipment | Principle of Operation | Maintenance Requirements |
| Linear Accelerator (LINAC) | Accelerates electrons to generate X-rays | Daily beam calibration, monthly servicing |
| Cobalt-60 Unit | Uses gamma rays from radioactive decay | Source replacement every 5–7 years |
| Brachytherapy | Radioactive seeds implanted in the body | Dosimetry verification before implantation |
| Infusion Pumps | Controls drug flow into the bloodstream | Calibration and tubing replacement |
| Biosafety Cabinets | Protects from chemotherapy exposure | Airflow monitoring and filter replacement |
4. Conclusion
- Radiotherapy equipment (LINAC, Cobalt-60) delivers targeted radiation therapy.
- Chemotherapy equipment (infusion pumps, biosafety cabinets) ensures safe drug administration.
- Regular maintenance is crucial for patient safety and treatment accuracy.
