Accurate image registration for CT-CT, CT-MRI for brain is necessary to obtain clinical information from diagnostic images and translate the information to radiotherapy treatment planning CT images. Mostly in cases of Post-Surgery cases that have been operated outside hospitals and are being referred for Post-Operative adjuvant Radiotherapy to our Centre, where the pre-operative volume is very ...

The cardiac model of the 4D NCAT phantom was enhanced by incorporating a physiological basis from which to realistically model left ventricular (LV) motion defects. A finite element mechanical model of the LV was developed to simulate deficits in contractile function and to study the effect of ischemia on LV function. The model geometry was based on high resolution CT and MRI data sets of a hea...

OBJECTIVES To investigate the impact of respiratory motion on localization, and quantification of lung lesions for the Gross Tumor Volume utilizing a fully automated Auto3Dreg program and dynamic NURBS-based cardiac-torso digitized phantom (NCAT). METHODS Respiratory motion may result in more than 30% underestimation of the SUV values of lung, liver and kidney tumor lesions. The motion correc...

This study is aimed at verifying the dosimetric performance of a treatment planning system (TPS) and to as well compare the accuracy of the measured absorbed dose of the solid water phantom against the inhouse phantom. In this study, a phantom for use in radiotherapy treatment planning of human trunk anatomical region has been designed with six hollows for inserting materials mimicking differen...

Background: HDR brachytherapy is one of the commonest methods of nasopharyngeal cancer treatment. In this method, depending on how advanced one tumor is, 2 to 6 Gy dose as intracavitary brachytherapy is prescribed. Due to high dose rate and tumor location, accuracy evaluation of treatment planning system (TPS) is particularly important. Common methods used in TPS dosimetry are based on computat...

background: accurate voxel phantom is needed for dosimetric simulation in radiation therapy for malignant tumors in female pelvic region. however, most of the existing voxel phantoms are constructed on the basis of caucasian or non-chinese population. materials and methods: a computational framework for constructing female pelvic voxel phantom for radiation dosimetry was performed based on chin...

introduction radiotherapy with small fields is used widely in newly developed techniques. additionally, dose calculation accuracy of treatment planning systems in small fields plays a crucial role in treatment outcome. in the present study, dose calculation accuracy of two commercial treatment planning systems was evaluated against monte carlo method. materials and methods siemens once or linea...

an important need in radiation therapy is a fast and accurate treatment planning system. this system using ct data and characteristics of the radiation beam, calculates the dose in all points of the patient’s volume. two main factors in planning system are “accuracy” and “speed”. according to these factors, various generation of treatment planning systems are developed.   this article is the re...

This paper presents an anthropomorphic phantom study of dose delivered to a specific point during tangential breast irradiation to verify monitor unit calculations. Measurements were made using a 0.6 cc Farmer type cylindrical ionization chamber in the phantom and compared to calculations made on a three-dimensional radiotherapy treatment planning system using single digitized contour through t...

Karin Andersson (2018): Metal Artifacts in Computed Tomography – impact of reduction methods on image quality and radiotherapy treatment planning. Örebro Studies in Medicine 172. Degradation of image quality by metal artifacts is a common problem in computed tomography (CT) imaging, which can limit the diagnostic value of a CT examination and also introduce inaccuracies in radiotherapy (RT) tre...