A Wide-Field Micro-Computed Tomography Detector: Micron Resolution at Half-centimeter Scale

Ideal 3-dimensional imaging of many complex samples, such as biological tissues made up of micro-scale structures extending over millimeter- to centimeter-scale tissue samples and organisms, requires both a wide field-of-view and high resolution. With existing optics and detectors used for micro-CT imaging, sub-micron pixel resolution can only be achieved for fields-of-view of <2 mm. This manuscript presents a unique detector system with a 6-mm field-of-view image circle and 0.5 μm pixel size that can be used in both synchrotron facilities and tabletop micro-CT units. A resolution-test pattern with linear microstructures and whole adult Daphnia magna were imaged on Beamline 8.3.2 of the Advanced Light Source. Volumes of 10,000 × 10,000 × 7,096 isotropic 0.5 μm voxels were reconstructed over a 5.0 × 3.5 mm field-of-view. Measurements in the projection domain confirmed a 1.182 μm measured spatial resolution that is largely Nyquist-limited. This unprecedented combination of field-of-view and resolution dramatically reduces the need for sectional scans and computational stitching for large samples, ultimately offering the means to elucidate change in tissue and cellular morphology in the context of larger whole, intact model organisms and specimens. This development is also anticipated to benefit micro-CT imaging in materials science, microelectronics, agricultural science, and biomedical engineering.

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Assessment of Global Ocular Structure Following Spaceflight Using a Micro-Computed Tomography (Micro-CT) Imaging Method

Journal of Visualized Experiments ◽

10.3791/61227 ◽

2020 ◽

Author(s):

Gina D. Roque-Torres ◽

Nina C. Nishiyama ◽

Seta Stanbouly ◽

Xiao Wen Mao

Keyword(s):

Computed Tomography ◽

Ct Imaging ◽

Imaging Method ◽

Micro Ct ◽

Micro Computed Tomography ◽

Ocular Structure

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Micro-computed tomography for natural history specimens: a handbook of best practice protocols

European Journal of Taxonomy ◽

10.5852/ejt.2019.522 ◽

2019 ◽

Author(s):

Kleoniki Keklikoglou ◽

Sarah Faulwetter ◽

Eva Chatzinikolaou ◽

Patricia Wils ◽

Jonathan Brecko ◽

...

Keyword(s):

Computed Tomography ◽

Natural History ◽

Best Practice ◽

Ct Imaging ◽

Three Dimensions ◽

X Rays ◽

Micro Ct ◽

Micro Computed Tomography ◽

Ct Technology ◽

Non Destructive

Micro-computed tomography (micro-CT or microtomography) is a non-destructive imaging technique using X-rays which allows the digitisation of an object in three dimensions. The ability of micro-CT imaging to visualise both internal and external features of an object, without destroying the specimen, makes the technique ideal for the digitisation of valuable natural history collections. This handbook serves as a comprehensive guide to laboratory micro-CT imaging of different types of natural history specimens, including zoological, botanical, palaeontological and geological samples. The basic principles of the micro-CT technology are presented, as well as protocols, tips and tricks and use cases for each type of natural history specimen. Finally, data management protocols and a comprehensive list of institutions with micro-CT facilities, micro-CT manufacturers and relative software are included.

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Nondestructive cryomicro-CT imaging enables structural and molecular analysis of human lung tissue

Journal of Applied Physiology ◽

10.1152/japplphysiol.00838.2016 ◽

2017 ◽

Vol 122 (1) ◽

pp. 161-169 ◽

Cited By ~ 16

Author(s):

Dragoş M. Vasilescu ◽

André B. Phillion ◽

Naoya Tanabe ◽

Daisuke Kinose ◽

David F. Paige ◽

...

Keyword(s):

Molecular Analysis ◽

Structural Changes ◽

Human Lung ◽

Three Dimensional ◽

Ct Imaging ◽

Matrix Composition ◽

Micro Ct ◽

Micro Computed Tomography ◽

Human Lung Tissue ◽

Lung Structure

Micro-computed tomography (CT) enables three-dimensional (3D) imaging of complex soft tissue structures, but current protocols used to achieve this goal preclude cellular and molecular phenotyping of the tissue. Here we describe a radiolucent cryostage that permits micro-CT imaging of unfixed frozen human lung samples at an isotropic voxel size of (11 µm)3 under conditions where the sample is maintained frozen at −30°C during imaging. The cryostage was tested for thermal stability to maintain samples frozen up to 8 h. This report describes the methods used to choose the materials required for cryostage construction and demonstrates that whole genome mRNA integrity and expression are not compromised by exposure to micro-CT radiation and that the tissue can be used for immunohistochemistry. The new cryostage provides a novel method enabling integration of 3D tissue structure with cellular and molecular analysis to facilitate the identification of molecular determinants of disease. NEW & NOTEWORTHY The described micro-CT cryostage provides a novel way to study the three-dimensional lung structure preserved without the effects of fixatives while enabling subsequent studies of the cellular matrix composition and gene expression. This approach will, for the first time, enable researchers to study structural changes of lung tissues that occur with disease and correlate them with changes in gene or protein signatures.

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Sensitivity of micro-computed tomography (micro-CT) imaging to visualize skeletal variations and malformations in embryo-fetal development toxicity studies

Reproductive Toxicology ◽

10.1016/j.reprotox.2019.07.048 ◽

2019 ◽

Vol 88 ◽

pp. 28

Author(s):

Arun K. Tatiparthi ◽

Cherie D. Qualls ◽

Paul Bushdid ◽

Katherine M. Murray ◽

Alexandra K. Groeller ◽

...

Keyword(s):

Computed Tomography ◽

Fetal Development ◽

Ct Imaging ◽

Micro Ct ◽

Micro Computed Tomography ◽

Toxicity Studies

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Diagnostic Yield of Micro-Computed Tomography (micro-CT) Versus Histopathology of a Canine Oral Fibrosarcoma

Journal of Veterinary Dentistry ◽

10.1177/0898756420926519 ◽

2020 ◽

Vol 37 (1) ◽

pp. 14-21

Author(s):

Matthias C. Eberspächer-Schweda ◽

Kira Schmitt ◽

Stephan Handschuh ◽

Andrea Fuchs-Baumgartinger ◽

Alexander M. Reiter

Keyword(s):

Computed Tomography ◽

Contrast Agent ◽

Tumor Volume ◽

Ct Imaging ◽

Image Resolution ◽

Surrounding Tissue ◽

Histopathological Diagnosis ◽

Micro Ct ◽

Micro Computed Tomography ◽

Tumor Margins

Micro-computed tomography (micro-CT) imaging currently gains increased interest in human as well as veterinary medicine. The ability to image 3-dimensional (3D) biopsy specimens nondestructively down to 1 µm spatial resolution makes it a promising tool for microscopic tissue evaluation in addition to histopathology. Visualizing tumor margins and calculating tumor load on 3D reconstructions may also enhance oncological therapies. The objective of this study was to describe the workflow from tumor resection to histopathological diagnosis, using both routine hematoxylin-eosin (HE)-stained sections and micro-CT tomograms on a stage II oral fibrosarcoma in a 7-year-old Hovawart dog. The maxillectomy specimen was fixed with formalin and stained with an X-ray dense soft tissue contrast agent. Micro-CT imaging was done using an ex vivo specimen micro-CT device. Tumor margins could not be exactly determined on micro-CT tomograms due to limited image resolution and contrast. Histopathology was performed after washing out the contrast agent. It showed neoplastic cells infiltrating the surrounding tissue further than assumed from micro-CT images. A total tumor volume of 10.3 cm3 could be calculated based on correlating micro-CT tomograms with HE-stained sections. This correlative approach may be of particular interest for oncological therapy. More than that, micro-CT imaging technology supported histopathology by means of 3D orientation and selection of slices to be cut on determining tumor margins. In this clinical case report, micro-CT imaging did not provide unambiguous clinical evidence for oncological decision-making, but it showed potential to support histopathology and calculate tumor volume for further clinical use.

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Three-Dimensional Whole-Organ Characterization of the Regional Alveolar Morphology in Normal Murine Lungs

Frontiers in Physiology ◽

10.3389/fphys.2021.755468 ◽

2021 ◽

Vol 12 ◽

Author(s):

Mauricio A. Sarabia-Vallejos ◽

Pedro Ayala-Jeria ◽

Daniel E. Hurtado

Keyword(s):

Surface Density ◽

Current Knowledge ◽

Regional Distribution ◽

Volume Ratio ◽

Ct Imaging ◽

Micro Ct ◽

Sprague Dawley ◽

Micro Computed Tomography ◽

Chronic Respiratory Diseases ◽

Alveolar Surface

Alveolar architecture plays a fundamental role in the processes of ventilation and perfusion in the lung. Alterations in the alveolar surface area and alveolar cavity volume constitute the pathophysiological basis of chronic respiratory diseases such as pulmonary emphysema. Previous studies based on micro-computed tomography (micro-CT) of lung samples have allowed the geometrical study of acinar units. However, our current knowledge is based on the study of a few tissue samples in random locations of the lung that do not give an account of the spatial distributions of the alveolar architecture in the whole lung. In this work, we combine micro-CT imaging and computational geometry algorithms to study the regional distribution of key morphological parameters throughout the whole lung. To this end, 3D whole-lung images of Sprague–Dawley rats are acquired using high-resolution micro-CT imaging and analyzed to estimate porosity, alveolar surface density, and surface-to-volume ratio. We assess the effect of current gold-standard dehydration methods in the preparation of lung samples and propose a fixation protocol that includes the application of a methanol-PBS solution before dehydration. Our results show that regional porosity, alveolar surface density, and surface-to-volume ratio have a uniform distribution in normal lungs, which do not seem to be affected by gravitational effects. We further show that sample fixation based on ethanol baths for dehydration introduces shrinking and affects the acinar architecture in the subpleural regions. In contrast, preparations based on the proposed dehydration protocol effectively preserve the alveolar morphology.

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STM studies of crystal growth

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100086179 ◽

1991 ◽

Vol 49 ◽

pp. 374-375

Author(s):

M. G. Lagally

Keyword(s):

Crystal Growth ◽

Molecular Beam ◽

Chemical Vapor ◽

Sputter Deposition ◽

Field Of View ◽

Scanning Tunneling ◽

Wide Field ◽

Tunneling Microscopy ◽

Wide Field Of View ◽

The One

It has been recognized since the earliest days of crystal growth that kinetic processes of all Kinds control the nature of the growth. As the technology of crystal growth has become ever more refined, with the advent of such atomistic processes as molecular beam epitaxy, chemical vapor deposition, sputter deposition, and plasma enhanced techniques for the creation of “crystals” as little as one or a few atomic layers thick, multilayer structures, and novel materials combinations, the need to understand the mechanisms controlling the growth process is becoming more critical. Unfortunately, available techniques have not lent themselves well to obtaining a truly microscopic picture of such processes. Because of its atomic resolution on the one hand, and the achievable wide field of view on the other (of the order of micrometers) scanning tunneling microscopy (STM) gives us this opportunity. In this talk, we briefly review the types of growth kinetics measurements that can be made using STM. The use of STM for studies of kinetics is one of the more recent applications of what is itself still a very young field.

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