Preliminary evaluation of optical CT scanning versus MRI for nPAG gel dosimetry: The Ghent experience

High resolution gel-dosimetry by optical-CT and MR scanning.

The increased intricacy of Intensity-Modulated-Radiation-Therapy (IMRT) delivery has created the need for a high-resolution 3D-dosimetry (three-dimensional) system capable of measuring and verifying the complex delivery. Present clinical methods are inadequate being restricted to single points (e.g., ion-chambers) or to 2D planes (e.g., film), and are labor intensive. In this paper we show that...

Evaluation of MRI-based Polymer Gel Dosimetry for Measurement of CT Dose Index (CTDI) on 64 slices CT Scanners

Introduction: Computed tomography (CT) has numerous applications in clinical procedures but its main problem is its high radiation dose to the patients compared to other imaging modalities using x-ray. CT delivers approximately high doses to the nearby tissues due to the scattering effect, fan beam (beam divergence) and limited collimator efficiency. The radiation dose from multi-slice scanners...

3D dosimetry by optical-CT scanning.

The need for an accurate, practical, low-cost 3D dosimetry system is becoming ever more critical as modern dose delivery techniques increase in complexity and sophistication. A recent report from the Radiological Physics Center (RPC) (1), revealed that 38% of institutions failed the head-and-neck IMRT phantom credentialing test at the first attempt. This was despite generous passing criteria (w...

Designing and developing an in-house CCD based optical CT scanner for gel dosimetry

Introduction: Measurement of the complex 3D radiation dose distribution created with advanced radiotherapy techniques such as IMRT and SRS became very important. Polymer gel dosimetry (PGD) is proposed method to recording this dose distribution. MRI, X-ray CT, ultrasound, spectrophotometry and optical CT scanners can be used for readout of Polymer gel dosimeters. Although MRI i...

3D verification of a prostate IMRT treatment by polymer gel-dosimetry and optical-CT scanning