6 results match your criteria: "National Institute for Bioengineering[Affiliation]"

Use of Zernike moments to characterize dose conformity for radiotherapy treatment plans.

Appl Radiat Isot

July 2024

Centre for Molecular and Medical Physics, Physics Department, Faculty of Science, Universidad Central de Venezuela, Caracas, Venezuela; Centre for Medical Visualization, National Institute for Bioengineering, INABIO, Universidad Central de Venezuela, Caracas, Venezuela; Centro de Diagnóstico Docente Las Mercedes, Caracas, Venezuela. Electronic address:

Dose conformity is an essential parameter used in radiotherapy and radiosurgery that measures the correspondence of the dose distribution derived from a Treatment Planning System (TPS) with the actual volume to be treated, the Planning Treatment Volume (PTV). The present work uses a method based on the expansion of dose distributions and PTVs by three-dimensional Zernike polynomials and further comparison of their moments to define a general criterion of dose conformity. To carry on this study, data coming from 20 patients comprising 80 datasets exported from the TPS, which included imaging data (PTVs) and dose distributions corresponding to different treatment modalities: three-dimensional conformal radiotherapy, intensity-modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT), were used.

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Multifractal Analysis of Brain Tumor Interface in Glioblastoma.

Adv Neurobiol

March 2024

Centre for Medical Visualization, National Institute for Bioengineering, INABIO, Universidad Central de Venezuela and Centro de Diagnóstico Docente Las Mercedes, Caracas, Venezuela.

The dynamics of tumor growth is a very complex process, generally accompanied by numerous chromosomal aberrations that determine its genetic and dynamical heterogeneity. Consequently, the tumor interface exhibits a non-regular and heterogeneous behavior often described by a single fractal dimension. A more suitable approach is to consider the tumor interface as a multifractal object that can be described by a set of generalized fractal dimensions.

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Morphological and Fractal Properties of Brain Tumors.

Front Physiol

June 2022

Centre for Medical Visualization, National Institute for Bioengineering, INABIO, Universidad Central de Venezuela, Caracas, Venezuela.

Tumor interface dynamics is a complex process determined by cell proliferation and invasion to neighboring tissues. Parameters extracted from the tumor interface fluctuations allow for the characterization of the particular growth model, which could be relevant for an appropriate diagnosis and the correspondent therapeutic strategy. Previous work, based on scaling analysis of the tumor interface, demonstrated that gliomas strictly behave as it is proposed by the Family-Vicsek ansatz, which corresponds to a proliferative-invasive growth model, while for meningiomas and acoustic schwannomas, a proliferative growth model is more suitable.

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Study of cervical cancer through fractals and a method of clustering based on quantum mechanics.

Appl Radiat Isot

August 2019

Department of Physics, Universidad de Córdoba, 230002, Montería, Colombia. Electronic address:

Tumor growth in the cervix is a complex process. Understanding this phenomena is quite relevant in order to establish proper diagnosis and therapy strategies and a possible startpoint is to evaluate its complexity through the scaling analysis, which define the tumor growth geometry. In this work, tumor interface from primary tumors of squamous cells and adenocarcinomas for cervical cancer were extracted.

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It has been ascertained that the human brain is a complex system studied at multiple scales, from neurons and microcircuits to macronetworks. The brain is characterized by a hierarchical organization that gives rise to its highly topological and functional complexity. Over the last decades, fractal geometry has been shown as a universal tool for the analysis and quantification of the geometric complexity of natural objects, including the brain.

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It is a well-known fact that computational biomechanics and mechanobiology have deserved great attention by the numerical-methods community. Many efforts and works can be found in technical literature. This work deals with the modeling of nutrients and their effects on the behavior of intervertebral discs.

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