Modern radiation delivery technique aims at precise delivery of radiation dose like Stereotactic Body Radiotherapy, 3D Conformal Radiotherapy and Intensity Modulated Radiotherapy are commonly using now a days. These techniques are based on increased complexity of radiation delivery methods and therefore necessitate verification of computer calculated dose distribution by an accurate dosimetric method. Gel dosimeters absorb dose in a tissue-equivalent manner and capable of recording dose distributions 3 dimensionally. An Optical CT (OCT) scanner plays a major role for Gel dosimeter readout and in clinical radiation therapy as a 3-Dimensional Radiation Dosimetry.

Polymer Gel Dosimetry for Radiation Therapy.

This book provides a first comprehensive summary of the basic principles, instrumentation, methods, and clinical applications of three-dimensional dosimetry in modern radiation therapy treatment. The presentation reflects the major growth in the field as a result of the widespread use of more sophisticated radiotherapy approaches such as intensity-modulated radiation therapy and proton therapy, which require new 3D dosimetric techniques to determine very accurately the dose distribution. It is intended as an essential guide for those involved in the design and implementation of new treatment technology and its application in advanced radiation therapy, and will enable these readers to select the most suitable equipment and methods for their application. Chapters include numerical data, examples, and case studies.

Cancer is a dreadful disease characterized by out-of-control cell growth. The cancer harms the human body when damaged cells divide uncontrollably to form lumps or masses of tissue called tumors. Radiotherapy (RT) is one of the major modalities of cancer treatment and every alternate cancer patient will require radiation during the course of treatment. Over the years, RT has progressed considerably towards this goal by the development of three dimensional (3D) conformal radiation therapy techniques such as IMRT, Stereotactic Radiosurgery and Radiotherapy (SRS/SRT), Brachytherapy and etc. These techniques are becoming standards of practice benefiting a significant proportion of patients. Therefore the verification of the actual dose delivery is vital to the effective delivery of conformal RT. Conventional dosimeters such as, ion chambers, thermoluminescent dosimeters (TLDs) and radiographic film are only 1 and 2-D dosimeters, and therefore are limited in their ability to integrate radiation dose over 3-D volumes. Gel dosimetry is the only 3-D dosimetric technique which is capable of recording and integrating complex 3-D dose distributions and offers comprehensive verification.

Expand your understanding of the physics and practical clinical applications of advanced radiation therapy technologies with Khan's The Physics of Radiation Therapy, 5th edition, the book that set the standard in the field. This classic full-color text helps the entire radiation therapy team—radiation oncologists, medical physicists, dosimetrists, and radiation therapists—develop a thorough understanding of 3D conformal radiotherapy (3D-CRT), stereotactic radiosurgery (SRS), high dose-rate remote afterloaders (HDR), intensity modulated radiation therapy (IMRT), image-guided radiation therapy (IGRT), Volumetric Modulated Arc Therapy (VMAT), and proton beam therapy, as well as the physical concepts underlying treatment planning, treatment delivery, and dosimetry. In preparing this new Fifth Edition, Dr. Kahn and new co-author Dr. John Gibbons made chapter-by-chapter revisions in the light of the latest developments in the field, adding new discussions, a new chapter, and new color illustrations throughout. Now even more precise and relevant, this edition is ideal as a reference book for practitioners, a textbook for students, and a constant companion for those preparing for their board exams. Features Stay on top of the latest advances in the field with new sections and/or discussions of Image Guided Radiation Therapy (IGRT), Volumetric Modulated Arc Therapy (VMAT), and the Failure Mode Event Analysis (FMEA) approach to quality assurance. Deepen your knowledge of Stereotactic Body Radiotherapy (SBRT) through a completely new chapter that covers SBRT in greater detail. Expand your visual understanding with new full color illustrations that reflect current practice and depict new procedures. Access the authoritative information you need fast through the new companion website which features fully searchable text and an image bank for greater convenience in studying and teaching. This is the tablet version which does not include access to the supplemental content mentioned in the text.

This publication is aimed at students and teachers involved in teaching programmes in field of medical radiation physics, and it covers the basic medical physics knowledge required in the form of a syllabus for modern radiation oncology. The information will be useful to those preparing for professional certification exams in radiation oncology, medical physics, dosimetry or radiotherapy technology.

Radiation therapy, one of the most common forms of cancer treatment, is continually evolving with the introduction of new technology, more complex treatments and more advanced radiation dose calculations. To ensure the effectiveness and safety of modern radiation therapy, dose measurement tools must improve to accommodate these advances. X-ray computed tomography (CT) polymer gel dosimetry is a unique type of dosimeter that has many advantages and the potential to address some of the challenges in the verification of dose delivery and calculation in radiation therapy. This dissertation investigates the advancement of an x-ray CT polymer gel dosimetry system for use in clinical applications and in particular for deformable dose verification. The first part of this work consists of a reproducibility study of an established x-ray CT polymer gel dosimetry system in an effort to determine the accuracy and precision of dose measurements made with this system and the feasibility of interbatch and generic calibration. Gel measurements were found to have excellent agreement with Monte Carlo dose calculation when using a generic calibration curve. The excellent dosimetric and spatial accuracy established in this study suggest that this dosimetry system is ideally suited for the measurement of high-dose fractionation treatments such as stereotactic radiosurgery (SRS) or stereotactic body radiation therapy (SBRT). The second stage was the development and characterization of the first deformable x-ray CT polymer gel dosimetry system. This study established the setup reproducibility, deformation characteristics and dose response of the new deformable system. The dose response was found to be similar to that of the non-deformable system with similar dosimetric and spatial accuracy when compared to Monte Carlo dose calculation. The system was also found to have sub-millimetre setup reproducibility and the deformable dosimeter was found to reproducibly deform and relax for external compression of up to 30 mm and over 100 consecutive compressions. This work established several important characteristics of the new deformable dosimetry system and it shows excellent potential for use in the evaluation of deformable dose accumulation algorithms. The final component of this dissertation was the use of the newly developed deformable dosimetry system in the evaluation of a novel deformable dose accumulation algorithm, defDOSXYZ. Gel measurements and defDOSXYZ showed excellent agreement in the case of a static control case and this set a benchmark for deformable dose measurements. Measurements of deformed dose by the gel dosimeter showed significant disagreement with dose deformed by defDOSXYZ and the dosimetric differences were well outside the uncertainties established in the first two studies of this dissertation. The results from this study provided some insight into potential avenues of improvement for both the deformable dose calculation and deformable dose measurements. These results were also the first example of deforming dose measured by an x-ray CT read out gel dosimetry system. Overall, the results in this dissertation represent a significant advancement in x-ray CT polymer gel dosimetry and establish its suitability for several clinical applications.