title: 3D characterization of vascular architectures in experimental tumors based on LSFM microscopy and simulation of the oxygen distributions
creator: Neuholz, Alexander
subject: ddc-530
subject: 530 Physics
description: Tumors exhibit chaotic vascular networks, causing hypoxic and thus more radioresistant subregions, which limit the success of radiotherapy. In this work, an analysis  pipeline for 3D light-sheet fluorescence microscope (LSFM) images was established  to characterize entire tumoral vascular networks. Two tumor lines with different radiosensitivities were irradiated with protons in two fractionation schemes and compared to untreated control tumors and brain samples.  The vascular network characterization employed three parameter classes: (i) Parameters that were measurable on 2D histology and 3D LSFM showed a good agreement  between the two methods. (ii) Conventional 3D quantities, e.g., the number of interconnected vascular branches, were useful to separate different tissue types.  (iii) Graph-theoretic network parameters, e.g., the graph size, could be used for tissue  discrimination and revealed a radiation-induced decrease in the global network efficiency.  Furthermore, an existing oxygen transport simulation algorithm was numerically optimized and benchmarked. The simulated oxygen distributions within the experimental tissue samples revealed increased oxygenation after irradiation, indicating reoxygenation. These results, which also account for the tissue-specific properties of the  characterized vascular architectures, may be used to improve simulations for the radiation response of hypoxic tumors.
date: 2021
type: Dissertation
type: info:eu-repo/semantics/doctoralThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/30148/1/Alexander%20Neuholz%20%282021%29%20-%20PhD%20thesis.pdf
identifier: DOI:10.11588/heidok.00030148
identifier: urn:nbn:de:bsz:16-heidok-301480
identifier:   Neuholz, Alexander  (2021) 3D characterization of vascular architectures in experimental tumors based on LSFM microscopy and simulation of the oxygen distributions.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/30148/
rights: info:eu-repo/semantics/openAccess
rights: Please see front page of the work (Sorry, Dublin Core plugin does not recognise license id)
language: eng