Radiation absorbed dose to bladder walls from positron emitters in the bladder content

Area of Science:

• Medical Physics
• Radiation Dosimetry
• Nuclear Medicine

Background:

• Accurate absorbed dose calculation is vital for effective radiation therapy.
• Positron-emitting radiopharmaceuticals are increasingly used in diagnostics and therapeutics.
• Bladder wall dosimetry requires precise modeling of internal radiation sources.

Purpose of the Study:

• To develop and validate a method for calculating absorbed doses in static spherical bladder walls from internal positron emitters.
• To assess the radiation dose delivered to bladder walls from Fluorine-18 (F-18).

Main Methods:

• Developed a computational method integrating Loevinger and Bochkarev point source functions for beta dose calculation.
• Employed a line segment source array technique for spherical models.
• Utilized the specific gamma ray constant for gamma dose determination.
• Validated calculations using ultra-thin thermoluminescent dosimeters (TLDs).

Main Results:

• Calculated absorbed radiation doses to bladder walls for F-18 in static spherical bladder models (radii 2.0 and 3.5 cm).
• Demonstrated good agreement between computational results and experimental TLD measurements.
• The developed method provides accurate dosimetry for internal radionuclide sources.

Conclusions:

• The developed method is effective for calculating absorbed doses in bladder walls from positron emitters.
• This dosimetry technique supports precise radiation dose assessment in nuclear medicine and therapy.
• Experimental validation confirms the reliability of the computational approach for internal dosimetry.