A 3D system of springs and dashpots is presented to model the motion of a lung tumour during respiration. The main guiding factor in configuring the system is the spatial relationship between abdominal and lung tumour motion. A coupled, non-dimensional triple of ordinary differential equations models the tumour motion when driven by a 3D breathing signal. Asymptotic analysis is used to reduce t...

introduction: the respiratory system is both a route of entry and exit for toxins and injurious agents, as well as being a target for chemical substances and pathogens. therefore, an understanding of the structure and function of the migratory cell populations of pulmonary tissues including alveolar macrophages is central in a number of important disease processes. this study aimed to identify ...

lung exposure to sulfur mustard (sm) results in pulmonary complications, which is the main cause of long-term disability and morbidity. up to now, the precise mechanisms of sm-induced lung complications has not been identified. the aim of this study was to evaluate apoptosis in the lung tissue of sm-exposed individuals. the study was performed on archived lung paraffin-embedded tissue specimens...

Xiaoxiao Liu: Shape-correlated Statistical Modeling and Analysis for Respiratory Motion Estimation. (Under the direction of Stephen M. Pizer.) Respiratory motion challenges image-guided radiation therapy (IGRT) with location uncertainties of important anatomical structures in the thorax. Effective and accurate respiration estimation is crucial to account for the motion effects on the radiation ...

In lung stereotactic body radiotherapy (SBRT), variability of intrafractional target motion can negate the potential benefits of four-dimensional (4D) treatment planning that aims to account for the dosimetric impacts of organ motion. This study used tumor motion data obtained from CyberKnife SBRT treatments to quantify the reproducibility of probability motion function (pmf) of 37 lung tumors....

Martin Fuss, M.D. , remembers the old days when radiologists treated a large area to get at a small tumor. Back then, the bone-encased male prostate seemed like an immovable object, recalled Fuss, who directs the imageguided radiation therapy department at the Oregon Health Sciences University in Portland. But advanced imaging technology now makes it possible to spot the slightest movement, he ...