Related Experiment Video
Updated: Apr 14, 2026

Irradiator Commissioning and Dosimetry for Assessment of LQ α and β Parameters, Radiation Dosing Schema, and in vivo Dose Deposition
Published on: March 11, 2021
Small field dosimetry and analysis of flattening filter free beams in true beam system
K R Muralidhar1, Birendra Kumar Rout, K K D Ramesh
1Department of Radiation Physics, American Oncology Institute, Hyderabad, Andhra Pradesh, India.
Aim Of Study:
The purpose of this study was to report the dosimetric characteristics of the small fields in flattening filter free (FFF) beams (output measurements, profile analysis, surface dose and consistency) generated by medical linear accelerator and its variation with respect to flattened beams (FB).
Materials And Methods:
Surface doses were obtained for field sizes 1 × 1-40 × 40 cm(2). Field width and penumbra were analyzed for field sizes 1 × 1-40 × 40 cm(2). To take output factors for small fields, diode and micro chamber were used and data was taken at a source-to-surface distance (SSD) and extended SSD. Consistency checked for the dosimetric data for 1 year.
Results:
Surface doses were higher in FFF compared with FB up to 20 × 20 cm(2) field size. Measured field sizes were slightly lesser in FFF and penumbra values were increased with respect to field size in both FB and FFF. For small fields, diode values have shown more promising results than micro chamber. Small field output measurements at nominal SSD and extended SSD were well in agreement with each other. FFF beams showed good data consistency in 1 year duration.
Conclusion:
Small field dosimetry, surface dose, profile analysis and consistency of FFF beams in FFF photon beams were derived and data shown good consistency during 1 year duration.
More Related Videos
11:27Studying Soft-matter and Biological Systems over a Wide Length-scale from Nanometer and Micrometer Sizes at the Small-angle Neutron Diffractometer KWS-2
Published on: December 8, 2016
10:23Author Spotlight: A Machine-Vision Approach to Transmission Electron Microscopy Workflows, Results Analysis and Data Management
Published on: June 23, 2023