The small fields and sharp gradients typically encountered in proton radiosurgery require high spatial resolution dosimetric measurements, especially below 1-2 cm diameters. Radiochromic film provides high resolution, but requires postprocessing and special handling. Promising alternatives are diode detectors with small sensitive volumes (SV) that are capable of high resolution and real-time do...

Gafchromic films have been applied to X-ray dosimetry in diagnostic radiology. To correct nonuniformity errors in Gafchromic films, X-rays in the double-exposure technique can be replaced with ultraviolet (UV)-A rays. Intensities of the incident and transmitted UV-A rays were measured. However, it is unclear whether the chemical color change of Gafchromic films affects the UV-A transmission int...

Introduction: Small field dosimetry is challenging for radiotherapy dosimetry. measurement of the output factor in the air and water (Sc, Scp) is one of the input parameters for commissioning of treatment planning systems and beam modeling. The aims of this study are to measured Sc,Scp for small fields with EBT2 and Ion chamber and design a appropriate mini-phantom for small fi...

PURPOSE Dosimetric accuracy in radiation treatment of breast cancer is critical for the evaluation of cosmetic outcomes and survival. It is often considered that treatment planning systems (TPS) may not be able to provide accurate dosimetry in the buildup region. This was investigated in various treatment techniques such as tangential wedges, field-in-field (FF), electronic compensator (eComp),...

The purpose of this study was to investigate the effect of dose perturbations for two metallic spinal screw implants in proton beam therapy in the perpendicular and parallel beam geometry. A 5.5 mm (diameter) by 45 mm (length) stainless steel (SS) screw and a 5.5 mm by 35 mm titanium (Ti) screw commonly used for spinal fixation were CT-scanned in a hybrid phantom of water and solid water. The C...

Gafchromic XRCT radiochromic film is a self-developing high sensitivity radiochromic film product which can be used for assessment of delivered radiation doses which could match applications such as computed tomography (CT) dosimetry. The film automatically changes colour upon irradiation changing from a yellow to green/brown colour. The absorption spectra of Gafchromic XRCT radiochromic film a...

PURPOSE Bombarding high-Z material with x-ray radiation releases Auger electrons and Coster-Kronig electrons, along with deeper penetrating fluorescent x-rays and photoelectrons. The Auger and Coster-Kronig electron penetration distance is on the order of nanometers to micrometers in water or tissue, creating a large dose enhancement accompanied by a RBE greater than 1 at the cellular level. Th...

PURPOSE High atomic number (Z) materials have been considered as a method for enhancing radiation dose in tumors. The dose enhancement due to interactions of kilovoltage x-rays with high-Z materials (i.e., gold or iodine) has been well demonstrated through computational works. This study is to experimentally quantify the effect using gold nanoparticles (AuNPs) and iodine solutions, respectively...

The purpose of this study was to review application of a consistent correction method for the solid state detectors, such as thermoluminescent dosimeters (chips (cTLD) and powder (pTLD)), optically stimulated detectors (both closed (OSL) and open (eOSL)), and radiochromic (EBT2) and radiographic (EDR2) films. In addition, to compare measured surface dose using an extrapolation ionization chambe...