Image-Guided Radiation Therapy (IGRT)

Image-Guided Radiation Therapy (IGRT) is a type of radiation therapy that uses imaging technologies to guide the delivery of radiation to tumors. The goal of IGRT is to improve the accuracy and effectiveness of radiation therapy by ensuring that the radiation is delivered precisely to the tumor site, while minimizing damage to surrounding healthy tissues.

How IGRT Works

IGRT involves the use of imaging technologies such as X-rays, computed tomography (CT) scans, magnetic resonance imaging (MRI), or positron emission tomography (PET) scans to obtain detailed images of the tumor and surrounding tissues. These images are then used to guide the delivery of radiation therapy.

The process typically involves the following steps:

• Imaging: The patient undergoes imaging tests to obtain detailed pictures of the tumor and surrounding tissues.
• Tumor localization: The images are used to identify the exact location and size of the tumor.
• Radiation planning: A radiation oncologist uses the images to create a personalized treatment plan, which includes the precise delivery of radiation to the tumor site.
• Radiation delivery: The patient is positioned on a treatment table and the radiation therapy machine delivers the planned dose of radiation to the tumor site, guided by the imaging technologies.
• Verification: The position of the tumor and surrounding tissues is verified using imaging technologies before and during each treatment session to ensure accurate delivery of radiation.

Types of IGRT

There are several types of IGRT, including:

• Kilovoltage (kV) imaging: Uses X-rays to obtain images of the tumor and surrounding tissues.
• Megavoltage (MV) imaging: Uses high-energy X-rays to obtain images of the tumor and surrounding tissues.
• Cone-beam computed tomography (CBCT): Uses a rotating X-ray source and detector to obtain 3D images of the tumor and surrounding tissues.
• Helical tomotherapy: Uses a combination of CT scanning and radiation delivery to provide precise treatment of tumors.

Benefits of IGRT

The benefits of IGRT include:

• Improved accuracy: IGRT allows for more accurate delivery of radiation to the tumor site, reducing the risk of damage to surrounding healthy tissues.
• Increased effectiveness: IGRT can improve the effectiveness of radiation therapy by ensuring that the radiation is delivered precisely to the tumor site.
• Reduced side effects: IGRT can help reduce side effects by minimizing damage to surrounding healthy tissues.
• Personalized treatment: IGRT allows for personalized treatment plans, which can be tailored to the individual patient's needs.

Common Uses of IGRT

IGRT is commonly used to treat a variety of cancers, including:

• Prostate cancer
• Breast cancer
• Lung cancer
• Head and neck cancer
• Gynecologic cancers

Risks and Complications of IGRT

As with any radiation therapy, there are potential risks and complications associated with IGRT, including:

• Fatigue
• Skin reactions
• Nausea and vomiting
• Diarrhea
• Urinary problems

It is essential to discuss the potential risks and complications of IGRT with a radiation oncologist before undergoing treatment.