scholarly journals Evaluation of scaffold microstructure and comparison of cell seeding methods using micro-computed tomography-based tools

2020 ◽  
Vol 17 (165) ◽  
pp. 20200102
Author(s):  
Aleksi Palmroth ◽  
Sanna Pitkänen ◽  
Markus Hannula ◽  
Kaarlo Paakinaho ◽  
Jari Hyttinen ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Three Dimensional ◽  
3D Cell Culture ◽  
Adipose Derived Stem Cells ◽  
Micro Ct ◽  
Cell Seeding ◽  
Micro Computed Tomography ◽  
Tissue Engineering Scaffolds ◽  
Scaffold Architecture ◽  
Static Seeding

Micro-computed tomography (micro-CT) provides a means to analyse and model three-dimensional (3D) tissue engineering scaffolds. This study proposes a set of micro-CT-based tools firstly for evaluating the microstructure of scaffolds and secondly for comparing different cell seeding methods. The pore size, porosity and pore interconnectivity of supercritical CO 2 processed poly( l -lactide-co- ɛ -caprolactone) (PLCL) and PLCL/β-tricalcium phosphate scaffolds were analysed using computational micro-CT models. The models were supplemented with an experimental method, where iron-labelled microspheres were seeded into the scaffolds and micro-CT imaged to assess their infiltration into the scaffolds. After examining the scaffold architecture, human adipose-derived stem cells (hASCs) were seeded into the scaffolds using five different cell seeding methods. Cell viability, number and 3D distribution were evaluated. The distribution of the cells was analysed using micro-CT by labelling the hASCs with ultrasmall paramagnetic iron oxide nanoparticles. Among the tested seeding methods, a forced fluid flow-based technique resulted in an enhanced cell infiltration throughout the scaffolds compared with static seeding. The current study provides an excellent set of tools for the development of scaffolds and for the design of 3D cell culture experiments.

scholarly journals Micro-CT study of Middle Ordovician Spumellaria (radiolarians) from western Newfoundland, Canada

2020 ◽  
Vol 94 (3) ◽  
pp. 417-435 ◽  
Author(s):  
Sarah Kachovich ◽  
Jonathan C. Aitchison
Keyword(s):  
Computed Tomography ◽  
Three Dimensional ◽  
Detailed Examination ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Lower Paleozoic ◽  
X Ray ◽  
Middle Ordovician ◽  
Radiolarian Assemblage ◽  
Taxonomic Groups

AbstractA new, previously undescribed Middle Ordovician (middle Darriwilian: Dw2) radiolarian assemblage has been recovered from the Table Cove Formation at Piccadilly Quarry, western Newfoundland. Constituents of the fauna described herein are both distinctive and exceptionally well preserved. Three-dimensional X-ray micro-computed tomography (μ-CT) is used to make a detailed examination of four key spumellarian specimens. This technology enables visualization of hitherto ambiguous details of the internal morphologies of key lower Paleozoic taxonomic groups, among which a lack of knowledge has impeded resolution of higher taxonomic rankings.

scholarly journals Micro-computed tomography: A novel diagnostic technique for the evaluation of gastrointestinal specimens

2021 ◽  
Vol 09 (12) ◽  
pp. E1886-E1889
Author(s):  
Noboru Kawata ◽  
Alexei Teplov ◽  
Peter Ntiamoah ◽  
Jinru Shia ◽  
Meera Hameed ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Three Dimensional ◽  
Diagnostic Technique ◽  
Human Colon ◽  
Ffpe Tissue ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Cross Sectional ◽  
Tissue Samples ◽  
Formalin Fixed Paraffin Embedded

AbstractMicro-computed tomography (micro-CT) is a non-destructive modality that can be used to obtain high-resolution three-dimensional (3 D) images of the whole sample tissue; the usefulness of micro-CT has been reported for evaluation of breast cancer and lung cancer. However, this novel diagnostic technique has never been used for evaluating endoscopically resected gastrointestinal specimens. In the present study, we scanned 13 formalin-fixed paraffin-embedded (FFPE) tissue blocks of a normal human colon and gastric tissue samples using micro-CT. The evaluation comprised a comparison of the acquired whole block images with the images of the corresponding cross-sectional slice of the hematoxylin and eosin-stained slide. Micro-CT was able to produce images of the whole sample and clearly depict tissues such as glandular structures, muscularis mucosae, and blood vessels in the FFPE tissue blocks of normal gastrointestinal samples. Furthermore, the 3 D reconstructed could be used to create a cross-sectional image and reflected the surface structure of samples obtained from any site. Micro-CT has the potential to become a highly promising pathological diagnostic assistance tool for endoscopically resected gastrointestinal specimens in combination with conventional microscopic examination.

Upscaling Reservoir Rock Porosity by Fractal Dimension Using Three-Dimensional Micro-Computed Tomography and Two-Dimensional Scanning Electron Microscope Images

2020 ◽  
Vol 143 (1) ◽  
Author(s):  
Muhammad Jawad Munawar ◽  
Sandra Vega ◽  
Chengyan Lin ◽  
Mohammad Alsuwaidi ◽  
Naveed Ahsan ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Three Dimensional ◽  
Fractal Dimensions ◽  
Two Dimensional ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Sandstone Sample ◽  
The Core ◽  
Carbonate Sample ◽  
Scanning Electron

Abstract Scaling porosity of sedimentary rocks from the scale of measurement to the scale of interest is still a challenge. Upscaling of porosity can assist to accurately predict other petrophysical properties of rock at multiple scales. In this study, we use the two-dimensional (2D) scanning electron microscope (SEM) and three-dimensional (3D) X-ray micro-computed tomography (micro-CT) image to upscale porosity from the image scale to the core plug scale. A systematic imaging plan is deployed to capture rock properties of a carbonate and a sandstone sample, which are sensitive to the fractal nature of these rocks. Image analysis records wider pore spectrum (0.12–50 µm) in the carbonate sample than in sandstone (0.12–30 µm). The fractal dimensions are also higher in the carbonate than in the sandstone sample. Median, volume-weighted average of pore radius, and fractal dimensions derived from the image analysis are used as inputs in this equation. The results of the present study using this equation yielded to the best results on a resolution of 2.5 µm/voxel in the sandstone and 2.01 µm/voxel resolution in the carbonate sample for 3D micro-CT images, where fractal-scaling porosity matches well with the porosity measured at the core plug scale. The 2D SEM images provided a good estimation of porosity in the sandstone sample, where micro-CT imaging techniques could not capture the full pore spectrum. The fractal porosity equation showed promising results and offers a potential alternative way to estimate porosity when there are no routine core measurements available.

scholarly journals Imaging the aqueous humor outflow pathway in human eyes by three-dimensional micro-computed tomography (3D micro-CT)

2011 ◽  
Vol 92 (2) ◽  
pp. 104-111 ◽  
Author(s):  
Cheryl R. Hann ◽  
Michael D. Bentley ◽  
Andrew Vercnocke ◽  
Erik L. Ritman ◽  
Michael P. Fautsch
Keyword(s):  
Computed Tomography ◽  
Aqueous Humor ◽  
Three Dimensional ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Aqueous Humor Outflow ◽  
Human Eyes ◽  
Outflow Pathway

Three-Dimensional Quantification of Calcium Salt-Composite Resorption (CSC) In Vitro by Micro-computed Tomography (Micro-CT)

JOM ◽  
2014 ◽  
Vol 66 (4) ◽  
pp. 559-565 ◽  
Author(s):  
T. Winkler ◽  
X. Y. Dai ◽  
G. Mielke ◽  
S. Vogt ◽  
H. Buechner ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Calcium Salt ◽  
Three Dimensional ◽  
Micro Ct ◽  
Micro Computed Tomography

scholarly journals Cardiac Micro–Computed Tomography for Morphological and Functional Phenotyping of Muscle LIM Protein Null Mice

2007 ◽  
Vol 6 (4) ◽  
pp. 7290.2007.00022 ◽  
Author(s):  
Cristian T. Badea ◽  
Laurence W. Hedlund ◽  
Julie F. Boslego Mackel ◽  
Lan Mao ◽  
Howard A. Rockman ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Three Dimensional ◽  
Blood Pool ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Isotropic Resolution ◽  
Lim Protein ◽  
Muscle Lim Protein ◽  
The Difference ◽  
Time Required

The purpose of this study was to investigate the use of micro–computed tomography (micro-CT) for morphological and functional phenotyping of muscle LIM protein (MLP) null mice and to compare micro-CT with M-mode echocardiography. MLP null mice and controls were imaged using both micro-CT and M-mode echocardiography. For micro-CT, we used a custom-built scanner. Following a single intravenous injection of a blood pool contrast agent (Fenestra VC, ART Advanced Research Technologies, Saint-Laurent, QC) and using a cardiorespiratory gating, we acquired eight phases of the cardiac cycle (every 15 ms) and reconstructed three-dimensional data sets with 94-micron isotropic resolution. Wall thickness and volumetric measurements of the left ventricle were performed, and cardiac function was estimated. Micro-CT and M-mode echocardiography showed both morphological and functional aspects that separate MLP null mice from controls. End-diastolic and -systolic volumes were increased significantly three- and fivefold, respectively, in the MLP null mice versus controls. Ejection fraction was reduced by an average of 32% in MLP null mice. The data analysis shows that two imaging modalities provided different results partly owing to the difference in anesthesia regimens. Other sources of errors for micro-CT are also analyzed. Micro-CT can provide the four-dimensional data (three-dimensional isotropic volumes over time) required for morphological and functional phenotyping in mice.

Investigation of Liquid Water Content of a Compressed PEMFC GDL Using Micro-Computed Tomography

2012 ◽  
Author(s):  
Ronnie Yip ◽  
Aimy Bazylak
Keyword(s):  
Computed Tomography ◽  
Water Content ◽  
Liquid Water ◽  
Water Injection ◽  
Three Dimensional ◽  
Liquid Water Content ◽  
Gas Diffusion ◽  
Ex Situ ◽  
Micro Ct ◽  
Micro Computed Tomography

With the current lack of understanding of the water transport phenomenon in the porous gas diffusion layers (GDLs) of the polymer electrolyte membrane fuel cells (PEMFCs), GDL designs are primarily implemented on a costly trial-and-error basis. In this work, an ex-situ device, suitable for micro-computed tomography (micro-CT) imaging, was designed to facilitate liquid water invasion of a GDL sample under flow field compression. The millimeter-scale apparatus allows for water injection from a point source with an opening diameter of 0.8 mm. A sample of felt-based Freudenberg GDL (H2315) was examined for the current study. Using micro-CT, the sample was scanned, before and after water invasion, to obtain high resolution, three-dimensional reconstructions of the dry GDL microstructures, as well as the liquid water patterns after breakthrough. These results were used to find the effect of liquid water content on the effective through-plane porosity for the felt-based Freudenberg GDL.

Detection of Marginal Leakage of Class V Restorations In Vitro by Micro–Computed Tomography

2014 ◽  
Vol 39 (2) ◽  
pp. 174-180 ◽  
Author(s):  
XY Zhao ◽  
SB Li ◽  
LJ Gu ◽  
Y Li
Keyword(s):  
Computed Tomography ◽  
Resin Composite ◽  
Nitrate Solution ◽  
Three Dimensional ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Class V ◽  
Enamel Structure ◽  
Significant Difference

SUMMARY This in vitro study evaluated the efficacy of micro–computed tomography (CT) in marginal leakage detection of Class V restorations. Standardized Class V preparations with cervical margins in dentin and occlusal margins in enamel were made in 20 extracted human molars and restored with dental bonding agents and resin composite. All teeth were then immersed in 50% ammoniacal silver nitrate solution for 12 hours, followed by a developing solution for eight hours. Each restoration was scanned by micro-CT, the depth of marginal silver leakage in the central scanning section was measured, and the three-dimensional images of the silver leakage around each restoration were reconstructed. Afterward, all restorations were cut through the center and examined for leakage depth using a microscope. The silver leakage depth of each restoration obtained by the micro-CT and the microscope were compared for equivalency. The silver leakage depth in cervical walls observed by micro-CT and microscope showed no significant difference; however, in certain cases the judgment of leakage depth in the occlusal wall in micro-CT image was affected by adjacent enamel structure, providing less leakage depth than was observed with the microscope (p<0.01). Micro-CT displayed the three-dimensional image of the leakage around the Class V restorations with clear borders only in the dentin region. It can be concluded that micro-CT can detect nondestructively the leakage around a resin composite restoration in two and three dimensions, with accuracy comparable to that of the conventional microscope method in the dentin region but with inferior accuracy in the enamel region.

scholarly journals Micro-Computed Tomography Analysis of Subchondral Bone Regeneration Using Osteochondral Scaffolds in an Ovine Condyle Model

2021 ◽  
Vol 11 (3) ◽  
pp. 891
Author(s):  
Taylor Flaherty ◽  
Maryam Tamaddon ◽  
Chaozong Liu
Keyword(s):  
Computed Tomography ◽  
Bone Regeneration ◽  
Subchondral Bone ◽  
Volume Ratio ◽  
Bone Volume ◽  
Osteochondral Defects ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Trabecular Thickness ◽  
Osteochondral Scaffold

Osteochondral scaffold technology has emerged as a promising therapy for repairing osteochondral defects. Recent research suggests that seeding osteochondral scaffolds with bone marrow concentrate (BMC) may enhance tissue regeneration. To examine this hypothesis, this study examined subchondral bone regeneration in scaffolds with and without BMC. Ovine stifle condyle models were used for the in vivo study. Two scaffold systems (8 mm diameter and 10 mm thick) with and without BMC were implanted into the femoral condyle, and the tissues were retrieved after six months. The retrieved femoral condyles (with scaffold in) were examined using micro-computed tomography scans (micro-CT), and the micro-CT data were further analysed by ImageJ with respect to trabecular thickness, bone volume to total volume ratio (BV/TV) ratio, and degree of anisotropy of bone. Statistical analysis compared bone regeneration between scaffold groups and sub-set regions. These results were mostly insignificant (p < 0.05), with the exception of bone volume to total volume ratio when comparing scaffold composition and sub-set region. Additional trends in the data were observed. These results suggest that the scaffold composition and addition of BMC did not significantly affect bone regeneration in osteochondral defects after six months. However, this research provides data which may guide the development of future treatments.

Sign in / Sign up

Export Citation Format

Share Document