PURPOSE VMAT involves multi-parameter modulations, thus presenting multi-dimensional challenges. Here, we present a viable approach to VMAT patient specific QA using EPID-based dosimetry for spine VMAT SRS casesMethods: Our spine VMAT SRS plans consisted of two full arcs and were optimized with 6 MV photons for a Varian Trilogy LINAC. The QA plans were computed by resetting all control points t...

ABSTRACT Background: In vivo measurements of applied dose during radiotherapy treatment, is important to ensure accurate dose delivery to patients. Uncertainty in dose delivery should fall within ±5% of the prescribed dose as recommended by ICRU. Assessment of dose for radiotherapy applications performed with various types of detectors. In this study, semiconductor diodes were used which have s...

PURPOSE The purpose of this work is to assess the variation in performance of various commercially available dosimetry diodes for quantitative small field dosimetry, specifically by intercomparing measurements of SRS cone factors. METHODS Measurements were made in 6 MV photon beams with fixed SRS cones for two accelerator-based SRS systems: a Varian Clinac iX (Varian/Zmed cones) at 600 MU/min...

New methods of dosimetry in computed tomography (CT) X-ray fields require the use of high-resolution detectors instead of pencil-type ionization chambers typically used for CT dose index (CTDI) measurements. This paper presents a study on the suitability of a wide range of ionization chambers, diodes, and a two-dimensional detector array, used primarily in radiation therapy, for CT and cone-bea...

Radiation Sensitive MOSFETs (RADFETs) have been commonly used as ionizing radiation dosimeters. The threshold voltage variation is the main transistor parameter for dosimetry, this directly related to total dose and it can be easily determined by using simple measurement biasing circuits. In work presented a novel experimental method determine optimal drain-source current value supplied p-type ...