Beam Me Up
Power Hungry
Control Freaks
It’s Not a LINAC?!
Behind the Curtain
100

This multi-digitated device shapes the radiation beam before it leaves the LINAC head.

What is a multileaf collimator (MLC)?

100

The part of the LINAC responsible for generating high-power microwaves.

What is the klystron or magnetron?

100

This system ensures the correct dose is delivered to the patient.

What is the monitor ion chamber?

100

This cobalt-based unit delivers gamma rays, often used in radiosurgery.

What is the Gamma Knife?

100

The vacuum tube where electrons accelerate inside the LINAC.

What is the accelerator waveguide?

200

This type of radiation beam is produced when electrons hit a high-Z target.

What is a photon (X-ray) beam?

200

This is the power source that feeds the klystron or magnetron.

What is the modulator?

200

These "beams" help align the patient with the treatment beam, often red, sometimes green, or blue.

What are room lasers or alignment lasers?

200

This robotic system delivers radiation without a conventional gantry.

What is the CyberKnife?

200

This bendy piece of hardware helps redirect electrons towards the target.

What is the bending magnet?

300

This is the low-energy electron beam that starts the whole acceleration process. Not a bow-and-arrow.

What is the electron gun?

300

This long finely crafted metal tube where electrons gain energy.

What is the waveguide?

300

This kind of radiation safety feature shuts the beam off if parameters go out of range.

What is an interlock system?

300

This older device delivers kilovoltage X-rays, often for superficial skin treatments.

What is Orthovoltage therapy (or superficial X-ray unit)?

300

This mode increases the dose rate by removing the beam flattening device.

What is flattening filter free mode?

400

This effect dominates dose fall-off for high-energy X-ray beams. (don't be rectangular)

What is the inverse square law?

400

The typical frequency (within GHz) used by most clinical LINACs.

What is 3 GHz (S-band)?

400

This form of radiation measurement happens during every treatment fraction. Not in utero.

What is in vivo dosimetry?

400

This machine uses a radioactive isotope for total body irradiation or blood irradiation.

What is a Cesium-137 or Cobalt-60 irradiator?

400

This phenomenon describes how electrons are accelerated to high velocities in the waveguide.

What is electromagnetic acceleration or RF acceleration?

500

This method of beam modulation creates intensity-modulated radiation therapy (IMRT).

What is dynamic MLC motion or step-and-shoot delivery?

500

This system of coolants prevents a catastrophic LINAC meltdown, typically using H2O.

What is the water cooling system?

500

This pre-treatment procedure confirms the patient position and beam targeting before delivery, often in 2D or 3D, and sometimes even in 4D.

What is image-guided radiation therapy (IGRT)?

500

This high-dose-rate brachytherapy device moves a tiny radioactive source through catheters.

What is HDR brachytherapy (High Dose Rate brachytherapy)?

500

This diagnostic test is performed to verify beam energy and symmetry.

What is a monthly or annual QA beam profile test?

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