HEИндивидуална стипендия2022–2024

BioDir-X · An X-ray beam tracking approach to retrieve directional information in biological specimens

„Хоризонт Европа“ — Действия „Мария Склодовска-Кюри“

Период: 2022-09-01 → 2024-11-30
Финансиране от ЕС: 172 750 €
Участници: 2
Схема: HORIZON-TMA-MSCA-PF-EF

Линиите свързват координатора с партньорите.

Накратко на български

Посоката на нервните влакна в биологични тъкани се проучва чрез нов метод за рентгеново изображение. Това помага за по-доброто разбиране на функционалните връзки в нервната система и промените в нея при стареене.

Този кратък обзор е генериран от изкуствен интелект

Кратко обяснение, генерирано от езиков модел по текста на CORDIS. Оригиналът е по-долу.

Резултати накратко

An X-ray beam tracking approach to retrieve directional information in biological specimens

The complexity of the nervous system (NS) is mainly related to its multi-scale connectivity, from the synaptic connections up to axons and nerves. The mapping of such pathways represents the first step towards the understanding of the NS functional connectivity and its changing with aging. Currently, the gold standard for the non-invasive investigation of fiber connectivity is the magnetic resonance diffusion tensor imaging which is based on the measurement of the thermal motion of water molecules in the specimen. While it meets the requirements for clinical usage, it suffers from low resolution, typically in the range of 1-2 mm in humans and around 100 microns in animals, that is still coarse compared to the size of fibers bundles. This scale is unsuitable for high-resolution applications such as preclinical small animal imaging. In addition, the characterization of fibers direction on a micrometric scale has applications also in materials science, such as for the investigation of composites. In this case, both the absence of water in the specimen and the low resolution prevents the use of DTI, making X-ray directional imaging the only viable solution. It is worth noting that small size of the fibers requires sub-micron spatial resolution to resolve and follow them through computed tomography (CT). While this is within the capabilities of state-of-the-art laboratory micro-CT systems, it typically imposes a small field of view providing only a local description of fibres arrangement. Therefore, the availability of an X-ray technique providing directional information over a large field of view is needed. In addition, the use of incoherent or partially coherent X-ray techniques will allow an easy implementation into laboratories. In this project, we proposed the use of the X-ray beam tracking technique based on a single absorption mask to retrieve directional information from a biological specimen. This has several advantages over other X-ray techniques such as grating interferometry. Specifically, the use a single absorption mask greatly reduced the complexity of the system improving its stability and does not require a partially coherent beam as it is needed for the speckle imaging.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз

Цел на проекта

The analysis of the directionality of fibres forming the white matter is a fundamental task in the investigation of the nervous system (NS), in terms of understanding its development and ageing as well as many neurological conditions. The imaging of white matter directionality is usually accomplished by means of diffusion tensor magnetic resonance imaging (DTI), which exploits the anisotropic diffusion of water molecules in the NS parenchyma. While DTI meets all the requirements for clinical imaging, it suffers from low resolution, which makes it difficult for pre-clinical small animal imaging where high resolution is required. In addition, it cannot be used for the imaging of materials where no water is present, requiring an alternative technique. In both cases, this can be represented by X-rays, which provide high resolution as well as the capability to extract directional information. However conventional, attenuation-based imaging is not directional, and the multi-modal capability offered by the new phase contrast techniques must be used. In addition to attenuation, these techniques also provide refraction and ultra-small angle scattering, which are directional signals and can be exploited to retrieve fibre orientation on a multi-scale level, above and below the system’s resolution. In particular, the retrieval of directional information from dark-field has been demonstrated by means of grating interferometry, which requires the use of two or three optical elements depending on the source size. The main goal of the project is to introduce a beam tracking (BT) multi-modal technique as an alternative for directional imaging. BT is based on the use of a single mask regardless of the source size, therefore providing the same capabilities as grating interferometry but a significantly simpler and more versatile setup. Directional BT will be used to extract the direction of fibres in sections of murine NS using both synchrotron facilities and laboratory sources.

Оригинален текст от CORDIS (на английски).

Участници

CONSIGLIO NAZIONALE DELLE RICERCHE · RomaКоординаторИталия
MUSEO STORICO DELLA FISICA E CENTRO STUDI E RICERCHE ENRICO FERMI · RomaИталия