N Singh
PhD, Assistant Professor of Medical Physics, Department of Radiotherapy King George’s Medical University, Lucknow, Uttar Pradesh, India
[ 1 ] - Evaluation of Volumetric Doses of Organs at Risk in Carcinoma Cervix Patients with HDR Intracavitary Brachytherapy and Comparison of CT-based and Conventional Plans
Background: Brachytherapy treatment planning in cervix carcinoma patients using two dimensional (2D) orthogonal images provides only point dose estimates while CT-based planning provides volumetric dose assessment helping in understanding the correlation between morbidity and the dose to organs at risk (OARs) and treatment volume. Objective: Aim of present study is to compare Internationa...
[ 2 ] - Evaluation of Electron Specific Absorbed Fractions in Organs of Digimouse Voxel Phantom Using Monte Carlo Simulation Code FLUKA
Background: For preclinical evaluations of radiopharmaceuticals, most studies are carried out on mice. Values of electron specific absorbed fractions (SAF) have had vital role in the assessment of absorbed dose. In past studies, electron specific absorbed fractions were given for limited source target pairs using older reports of human organ compositions.Objective: Electron specific absorbed fr...
[ 3 ] - Evaluation of Lung Density and Its Dosimetric Impact on Lung Cancer Radiotherapy: A Simulation Study
Background: The dosimetric parameters required in lung cancer radiation therapy are taken from a homogeneous water phantom; however, during treatment, the expected results are being affected because of its inhomogeneity. Therefore, it becomes necessary to quantify these deviations.Objective: The present study has been undertaken to find out inter- and intra- lung density variations and its dosi...
[ 4 ] - Evaluation of AAA and XVMC Algorithms for Dose Calculation in Lung Equivalent Heterogeneity in Photon Fields: A Comparison of Calculated Results with Measurements
Aims: The aims of the present work are (1) to evaluate dose calculation accuracy of two commonly used algorithms for 15 MV small photon fields in a medium encompassing heterogeneity and (2) to compare them with measured results obtained from gafchromic film EBT2.Materials and Methods: Authors employed kailwood (Pinus Wallichiana) to mimic lung. Briefly, seven Kailwood plates, each measuring 25x...
[ 5 ] - Estimation of Photon Specific Absorbed Fractions in Digimouse Voxel Phantom using Monte Carlo Simulation Code FLUKA
Background: Most preclinical studies are carried out on mice. For internal dose assessment of a mouse, specific absorbed fraction (SAF) values play an important role. In most studies, SAF values are estimated using older standard human organ compositions and values for limited source target pairs.Objective: SAF values for monoenergetic photons of energies 15, 50, 100, 500, 1000 and 4000 keV...
[ 6 ] - Evaluating Performance of Algorithms in Lung IMRT: A Comparison of Monte Carlo, Pencil Beam, Superposition, Fast Superposition and Convolution Algorithms
Background: Inclusion of inhomogeneity corrections in intensity modulated small fields always makes conformal irradiation of lung tumor very complicated in accurate dose delivery.Objective: In the present study, the performance of five algorithms via Monte Carlo, Pencil Beam, Convolution, Fast Superposition and Superposition were evaluated in lung cancer Intensity Modulated Radiotherapy plannin...
[ 7 ] - Radiation Induced Demyelination in Cervical Spinal Cord of the Head and Neck Cancer Patients after Receiving Radiotherapy
Background: Cervical spinal cord is important and radiosensitive. It is the most critical organ for the head and neck (H&N;) cancer patients during radiotherapy. If the delivered dose to the cord is more than tolerance dose, demyelination may occur. Objective: Current study aims to analyze the post radiotherapy status of cord in the H&N; cancer patients.Material and Methods: In this a...
[ 8 ] - Rectal and Bladder Dose Measurements in the Intracavitary Applications of Cervical Cancer Treatment with HDR Afterloading System: Comparison of TPS Data with MOSFET Detector
Background: Intracavitary brachytherapy plays a major role in management of cervical carcinoma. Assessment of dose received by OAR’s therefore becomes crucial for the estimation of radiation toxicities in HDR brachytherapy. Objective: Purpose of this study is to evaluate the role of in vivo dosimetry in HDR brachytherapy and to compare actual doses delivered to OAR’ s with those calculate...