Publications by authors named "Essa Mayyas"

Purpose: To analyze clinical toxicity and quality-of-life (QOL) outcomes among patients with stage I non-small cell lung cancer (NSCLC) after stereotactic body radiation therapy (SBRT) as a function of radiation dose and volume parameters.

Methods And Materials: In this institutional review board-approved study, 55 patients with stage I NSCLC who received SBRT (12 Gy × 4) and completed QOL forms were analyzed. Clinical symptoms and QOL outcomes were measured at baseline and at 3, 6, 12, 18, 24, and 36 months after SBRT.

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Background And Objective: The implementation of adaptive radiation therapy (ART) into routine clinical practice is technically challenging and requires significant resources to perform and validate each process step. The objective of this report is to identify the key components of ART, to illustrate how a specific automated procedure improves efficiency, and to facilitate the routine clinical application of ART.

Methods: Data was used from patient images, exported from a clinical database and converted to an intermediate format for point-wise dose tracking and accumulation.

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Purpose: Prostate deformation is assumed to be a secondary correction and is typically ignored in the planning target volume (PTV) margin calculations. This assumption needs to be tested, especially when planning margins are reduced with daily image-guidance. In this study, deformation characteristics of the prostate and seminal vesicles were determined, and the dosimetric impact on treatment plans with different PTV margins was investigated.

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Purpose: Setup errors and prostate intrafraction motion are main sources of localization uncertainty in prostate cancer radiation therapy. This study evaluates four different imaging modalities 3D ultrasound (US), kV planar images, cone-beam computed tomography (CBCT), and implanted electromagnetic transponders (Calypso/Varian) to assess inter- and intrafraction localization errors during intensity-modulated radiation therapy based treatment of prostate cancer.

Methods: Twenty-seven prostate cancer patients were enrolled in a prospective IRB-approved study and treated to a total dose of 75.

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We report on an improved method to interpret single molecule dissociation measurements using atomic force microscopy. We describe an easy to use methodology to reject nonspecific binding events, as well as estimating the number of multiple binding events. The method takes nonlinearities in the force profiles into account that result from the deformation of the used polymeric linkers.

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