OBJECTIVE To compare the inverse planning optimization based on total dose constraints versus conventional treatment plan (point A planning method) for cervical carcinoma, and evaluate the benefit of CT-based image-guided brachytherapy. METHODS We prospectively analyzed data of 10 consecutive patients with cervical cancer treated with external beam radiotherapy to the whole pelvis (45 Gy in 2...

Introduction: The aim of this study is to investigate the effect of partially used high photon energies on dosimetric parameters and integral doses of nasopharynx IMRT plans.   Materials and Methods: Two 7 coplanar IMRT plan were created for eleven patients (6 MV only IMRT plan in both phase1 and phase2 and 6 MV phase1-mixed energies (6 MV and 15 MV) phase2...

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...

PURPOSE Dose-volume histogram (DVH) is a clinically relevant criterion to evaluate a treatment plan quality. It is hence desirable to incorporate DVH constraints in treatment planning process for intensity modulated radiation therapy (IMRT). Yet, these constraints usually lead to difficulties due to their non-convex nature. The purpose of this project is to solve the IMRT optimization problem w...

We retrospectively generated IMRT plans for 14 NSCLC patients who had experienced grade 2 or 3 esophagitis (CTCAE version 3.0). We generated 11-beam and reduced esophagus dose plan types to compare changes in the volume and length of esophagus receiving doses of 50, 55, 60, 65, and 70 Gy. Changes in planning target volume (PTV) dose coverage were also compared. If necessary, plans were renormal...

PURPOSE To develop an automated technique for evaluating lung stereotactic body radiotherapy (SBRT) plan quality and predicting achievable lung dose constraints. METHODS We examined the workflow scripting capabilities of a radiation oncology software package (MIM Software Inc) for automatically generating mean dose gradients and overlap volume histograms (OVHs) for lung SBRT plans. Mean dose ...

BACKGROUND To evaluate in-silico the performance of a model-based optimization process for volumetric modulated arc therapy (RapidArc) applied to hepatocellular cancer treatments. PATIENTS AND METHODS 45 clinically accepted RA plans were selected to train a knowledge-based engine for the prediction of individualized dose-volume constraints. The model was validated on the same plans used for t...

For accurate prediction of normal tissue tolerance, it is important that the volumetric information of dose distribution be considered. However, in dosimetric optimization of intensity modulated beams, the dose-volume factor is usually neglected. In this paper we describe two methods of volume-dependent optimization for intensity modulated beams such as those generated by computer-controlled mu...