Optical computed tomography for gel dosimetry

How do CT scans use optics?
The parallel beam irradiation optical system is the key component of a CT scanner.
It consists of a parallel beam X-ray source (2) and the screen (3).
They are positioned so that they face each other in parallel with the origin (6) in between, both being in contact with the datum circle (6)..
How does gel dosimetry work?
Polymer gel dosimeters
Formation of tightly crosslinked polymer particles (microgels) induces changes in the physical properties of the dosimeter that can be detected using several imaging techniques (e.g., MRI, optical CT, x-ray CT and ultrasound scans) [26-35]..
How is dosimetry performed?
Internal dosimetry assessment relies on a variety of monitoring, bio-assay or radiation imaging techniques, whilst external dosimetry is based on measurements with a dosimeter, or inferred from measurements made by other radiological protection instruments..
What gel is used in CT scan?
A FXG gel composition is optimized for stereotactic and dynamic radiotherapy.
A new dual wavelength reading method of FXG gel is developed on a CT scanner.
The linear dose response of the gel is observed on the 0–10 Gy dose range..
What is the principle of gel dosimeter?
“Gel dosimeters” are based on chemical dosimeters in which radiation-induced chemical reactions occur.
The addition of gelling agents reduces the diffusion of chemical reaction products and, consequently, the dosimeter is spatially stabilized..
A clear benefit of gel dosimeters is that they can display a dose distribution, especially a highly conformal one as is produced by stereotactic radiosurgery techniques, so that it can be appreciated qualitatively in three dimensions without need of imaging systems or processing (see Figure 3, reference 95).
It provides physicians with in-situ image data in micrometer resolution within seconds.
OCT's working principle is similar to ultrasound but uses light instead of sound waves and is also free of potentially harmful ionizing radiation while being non-invasive.
The parallel beam irradiation optical system is the key component of a CT scanner.
It consists of a parallel beam X-ray source (2) and the screen (3).
They are positioned so that they face each other in parallel with the origin (6) in between, both being in contact with the datum circle (6).
The role of dosimetry is to determine the amount of radiation, i.e. dose, received by a person from the radiological examination.

Although there is much room for improvement in the image artifacts due to reflection and refraction of light and so on, OCT is expected as a modality for the future polymer gel dosimetry as the rapid, high-resolution, highly accurate evaluation tool.

This article describes an optical computed tomography (OCT) for polymer gel dosimetry, focusing on two systems recently constructed by us.

Radiation dosimetry in the fields of health physics and radiation protection is the measurement, calculation and assessment of the ionizing radiation dose absorbed by an object, usually the human body.
This applies both internally, due to ingested or inhaled radioactive substances, or externally due to irradiation by sources of radiation.

Optical computed tomography for gel dosimetry

How do CT scans use optics?

How does gel dosimetry work?

How is dosimetry performed?

What gel is used in CT scan?

What is the principle of gel dosimeter?