The purpose of this study was to compare three computed tomography (CT) images under different conditions-average intensity projection (AIP), free breathing (FB), mid-ventilation (MidV)-used for radiotherapy contouring and planning in lung cancer patients. Two image sets derived from four-dimensional CT (4DCT) acquisition (AIP and MidV) and three-dimensional CT with FB were generated and used t...

PURPOSE Blocks have been used to protect heart from potential radiation damage in left-sided breast treatments. Since cardiac motion pattern may not be fully captured on conventional 3DCT or 4DCT simulation scans, this study was intended to investigate the optimization of the heart block design taking the cardiac motion into consideration. MATERIALS AND METHODS Whole breast treatment plans us...

PURPOSE The effects of respiratory motion on the tumor dose can be divided into the gradient and interplay effects. While the interplay effect is likely to average out over a large number of fractions, it may play a role in hypofractionated [stereotactic body radiation therapy (SBRT)] treatments. This subject has been extensively studied for intensity modulated radiation therapy but less so for...

The main function of the respiratory system is gas exchange. Since many disease or injury conditions can cause biomechanical or material property changes that can alter lung function, there is a great interest in measuring regional lung function and mechanics. In this thesis, we present a technique that uses multiple respiratory-gated CT images of the lung acquired at different levels of inflat...

ID: 10123 Title: Effects of breathing variation on internal target volume (ITV) in respiratory gated radiation therapy Introduction: Accuracy of 4DCT reconstruction depends on reproducible patient breathing during scans and highly synchronized external surrogates. Studies have been conducted to investigate the effects of breathing variation on the motion information extracted from 4DCT (1, 2). ...

Background: Medical image interpolation is recently introduced as a helpful tool to obtain further information via initial available images taken by tomography systems. To do this, deformable image registration algorithms are mainly utilized to perform image interpolation using tomography images.Materials and Methods: In this work, 4DCT thoracic images of five real patients provided by DI...

Introduction Currently, the C-12 therapy performed at GSI cannot be applied to moving tumors because interplay between scanned ion beam and moving target does not allow controlled dose delivery. Several techniques are proposed to mitigate the influence of interplay. Among them are tracking [1], gating [2], rescanning [3], and use of margins. We used the 4D extension of GSI’s treatment planning ...

background: medical image interpolation is recently introduced as a helpful tool to obtain further information via initial available images taken by tomography systems. this information may be useful for better diagnosis of possible lesions or better tumor delineation at radiation treatment. to do this, deformable image registration algorithms are mainly utilized to perform image interpolation ...