Optical-CT gel-dosimetry II: Optical artifacts and geometrical distortion

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...

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...

How to perform dosimetry with Optical CT

Both polymer gels and PRESAGE radiochromic solid dosimeter, in conjunction with optical CT scanning system, have been employed to measure 3-D dose distribution. The 3-D dose maps obtained from these systems can provide a useful tool for dose verification on complex treatments such as IMRT, radiosurgery, and RapidArc. These complex treatments present high dose gradient regions in the boundaries ...

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...

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