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 ...

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...

conclusions pc-rplnd is one the major operations in the field of urology, which is associated with significant adjunctive surgeries. in appropriate cases, pc-rplnd was associated with good cancer specific survival in tertiary oncology center. results twenty-one patients underwent bilateral pc-rplnd. mean age was 26.3 years (ranged 16 - 47). mean size of retroperitoneal mass after chemotherapy w...

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 ...

BACKGROUND AND PURPOSE Intravoxel incoherent motion MR imaging can simultaneously measure the diffusion and perfusion characteristics of brain tumors. Our aim was to determine the utility of intravoxel incoherent motion-derived perfusion and diffusion parameters for assessing the treatment response of metastatic brain tumor following gamma knife radiosurgery. MATERIALS AND METHODS Ninety-one ...

background diffusion-weighted imaging (dwi) is a form of magnetic resonance imaging (mri) based on measuring the random brownian motion of water molecules within the biological tissues and is particularly useful in tumor characterization. objectives the purpose of this study was to evaluate the diagnostic value of dw mri and the apparent diffusion coefficient (adc) for preoperative grading of a...

PURPOSE To develop a tumor tracking method based on a surrogate-driven motion model, which provides noninvasive dynamic localization of extracranial targets for the compensation of respiration-induced intrafraction motion in high-precision radiation therapy. METHODS AND MATERIALS The proposed approach is based on a patient-specific breathing motion model, derived a priori from 4-dimensional p...

We propose a new markerless tracking technique of lung tumor motion by using an X-ray fluoroscopic image sequence for real-time image-guided radiation therapy (IGRT). A core innovation of the new technique is to extract a moving tumor intensity component from the fluoroscopic image intensity. The fluoroscopic intensity is the superimposition of intensity components of all the structures passed ...

Motion-adaptive radiotherapy techniques are promising to deliver truly ablative radiation doses to tumors with minimal normal tissue exposure by accounting for realtime tumor movement. However, a major challenge of successful applications of these techniques is the realtime prediction of breathing-induced tumor motion to accommodate system delivery latencies. Predicting respiratory motion in re...