Gel dosimetry

Gel dosimetry is a technique used in the field of radiation therapy to measure the dose distribution of radiation. This method is particularly useful in complex radiation fields where 3D dose distribution is required.

History

The concept of gel dosimetry was first introduced in the 1980s. The initial systems were based on Fricke's solution, which changes its chemical properties under the influence of radiation. The development of polymer and ferrous gels in the 1990s expanded the application of gel dosimetry in clinical practice.

Types of Gel Dosimeters

There are three main types of gel dosimeters: Fricke gel, polymer gel, and ferrous gel.

Fricke Gel

Fricke gel is based on the Fricke dosimeter, which uses a solution of ferrous sulfate, sulfuric acid, and water. The radiation-induced oxidation of Fe2+ to Fe3+ ions is proportional to the absorbed dose.

Polymer Gel

Polymer gel dosimeters contain monomers that polymerize upon irradiation. The degree of polymerization is dose-dependent, allowing for dose measurement.

Ferrous Gel

Ferrous gel dosimeters work on the principle of radiation-induced oxidation of ferrous ions to ferric ions. The ferric ions form a complex with xylenol orange, resulting in a color change proportional to the dose.

Applications

Gel dosimetry has a wide range of applications in radiation therapy, including quality assurance, treatment planning, and dose verification. It is particularly useful in techniques such as Intensity-Modulated Radiation Therapy (IMRT) and Stereotactic Body Radiation Therapy (SBRT) where complex dose distributions are required.

Advantages and Limitations

The main advantage of gel dosimetry is its ability to provide 3D dose distribution. However, it also has some limitations, including the need for specialized equipment and the difficulty in handling and storing the gels.

Future Directions

The future of gel dosimetry lies in the development of new gel systems with improved sensitivity and stability, as well as the integration of gel dosimetry with imaging techniques such as Magnetic Resonance Imaging (MRI).

This radiation related article is a stub. You can help WikiMD by expanding it.