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Surface Guided Radiation Therapy (SGRT)

What is surface guided radiation therapy?

Surface guided radiation therapy (SGRT) uses special cameras and lights to check your child’s position and movement during radiation treatment. This helps the radiation therapist put your child in the right position and keep them there during the treatment.

Surface guided radiation therapy machine with cameras
Surface guided radiation therapy machine with cameras

Surface Guided Radiation Therapy (SGRT) uses a system of cameras and lights to help position the patient for radiation treatment. 

How SGRT works

SGRT works with a system of cameras that are on the ceiling. The cameras send information about your child’s position to a computer program.

The SGRT cameras have a projector and sensors that make a 3D model of the skin by shining a light on it. The light has a pattern of dots that the cameras can follow. The dots are like markers that show the correct position. The cameras can see if your child moves or changes position by looking at the dots.

Benefits of SGRT

There are several benefits of SGRT. These include better accuracy and precision of radiation treatments and decreased session time. SGRT can also reduce the need for tattoo marks, although the marks may still be needed in many cases.

SGRT cameras do not give off any radiation. They only help your therapist check if you are in the right position and stay there during the treatment.

What to expect during SGRT

SGRT is painless and noninvasive. Your child may see the lights shining on them. Their skin might appear bright red or blue from the lights.

Because SGRT uses cameras to watch your child’s skin, the skin in the treated area must be bare. This means that clothing, blankets, or other items must be removed so they do not cover that part of the skin during the setup and treatment. For example, if your child gets radiation treatment near the stomach, they may have to lift or take off their shirt so the cameras can see the skin on their stomach.

It is important that the radiation treatment reaches the right place in your child’s body. SGRT is one way to ensure this. Other ways include putting small marks or tattoos on the skin, using special positioning devices, and taking pictures with X-rays. Your radiation therapy team will likely use a combination of methods to ensure the best possible care.

SGRT is not used in all centers and is not used for all patients.

Talk to your care team if you have questions.

Key points about SGRT

  • It is very important for your child to be in the correct position during radiation therapy.
  • Surface Guided Radiation Therapy (SGRT) uses special cameras and lights to help position your child for treatment.
  • Your child may see the lights on their skin, but it does not hurt.
  • Your care team might use other ways to position your child for radiation treatment, such as marks on the skin or positioning devices.

Reviewed: June 2024

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