Lung cancer is the leading cause of cancer-related deaths worldwide. Radiotherapy is one of the main treatment modalities of lung cancer. However, the achievable accuracy of radiotherapy treatment is limited for lung-based tumors due to respiratory motion. Four-dimensional (4D) radiotherapy explicitly accounts for anatomic motion by characterizing the motion, creating a treatment plan that acco...

abstractobjective: to investigate the impact of respiratory motion on localization, and quantification lung lesions for the gross tumour volume utilizing an in-house developed auto3dreg programme and dynamic nurbs-based cardiac-torso digitised phantom (ncat). methods: respiratory motion may result in more than 30% underestimation of the suv values of lung, liver and kidney tumour lesions. the m...

background: the aim of this work was to study the feasibility of constructing a fast thorax model suitable for simulating lung motion due to respiration using only one ct dataset. materials and methods: for each of six patients with different thorax sizes, two sets of ct images were obtained in single-breath-hold inhale and exhale stages in the supine position. the ct images were then analyzed ...

background: to determine which radiotherapy parameters are associated with the tumor response of locally advanced non-small cell lung cancer (nsclc) patients undergoing concurrent chemoradiotherapy. materials and methods: thirty one patients with iiia/iiib nsclc underwent chemoradiotherapy with a median dose of 63 gy. on our actual treatments, we made radiotherapy planning to cover the planning...

This study presented the analysis of free-breathing lung tumor motion characteristics using GE 4DCT and Varian RPM systems. Tumor respiratory movement was found to be associated with GTV size, the superior-inferior tumor location in the lung, and the attachment degree to rigid structure (e.g., chest wall, vertebrae, or mediastinum), with tumor location being the most important factor among the ...

In this paper, we present a real-time simulation and visualization framework that models a deformable surface lung model with tumor, simulates the tumor motion and predicts the amount of radiation doses that would be deposited in the moving lung tumor during the actual delivery of radiation. The model takes as input a subject-specific 4D Computed Tomography (4D CT) of lungs and computes a defor...

Lung radiotherapy is greatly benefitted when the tumor motion caused by breathing can be modeled. The aim of this paper is to present the importance of using anisotropic and subject-specific tissue elasticity for simulating the airflow inside the lungs. A computational-fluid-dynamics (CFD) based approach is presented to simulate airflow inside a subject-specific deformable lung for modeling lun...

This paper presents a study that demonstrates the potential of using finite element (FE) lung model constructed using 4D-MRI (3D + time) for tracking tumor motion during a respiratory cycle. A series of volumetric images of one lung cancer patient was acquired over time under free breathing and sorted into respiratory phases. A FE model of the lung with the tumor was constructed using the volum...

Currently in our clinic, a mega-voltage cone beam computed tomography (MVCBCT) scan is performed before each treatment for patient localization. For nonsmall cell lung cancer (NSCLC) patients, a strain gauge is used as an external surrogate to indicate tumor motion in both the planning stage and the treatment stage. However, it is likely that the amplitude of tumor motion varies between treatme...

OBJECTIVE To estimate a new technique for quantifying regional lung motion using 3D-MRI in healthy volunteers and to apply the technique in patients with intra- or extrapulmonary tumors. MATERIALS AND METHODS Intraparenchymal lung motion during a whole breathing cycle was quantified in 30 healthy volunteers using 3D-dynamic MRI (FLASH [fast low angle shot] 3D, TRICKS [time-resolved interpolat...