Micro-computed tomography
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Condylar hyperplasia is one of the causes of facial asymmetry and malocclusion, characterized by enlargement of the lower jaw due to excessive condyle growth activity. The aim of this study was to use micro-computed tomography (micro-CT) to evaluate the bone architecture of the condylar head and determine whether there are differences between patients with various forms of unilateral condylar hyperplasia (UCH): hemimandibular hyperplasia, elongation, and mixed form. The cohort consisted of 28 patients with a mean age of 21.9 years. All patients underwent surgical treatment (condylar shaving) for active pathological growth activity. The portion of the condylar head removed was imaged by micro-CT and subsequently evaluated. Micro-CT imaging and semiquantitative and quantitative evaluation of the bone structure (percentage bone volume, surface density, trabecular thickness, trabecular separation, degree of anisotropy, and porosity of the subchondral bone) did not reveal significant differences between the individual types of condylar hyperplasia (P > 0.05). There were no significant differences in bone structure between the anterior and posterior portions of the condylar head. No statistically significant differences between individual groups of UCH were found in the micro-CT evaluation of the condylar head bone architecture.
- MeSH
- asymetrie obličeje * diagnostické zobrazování chirurgie etiologie MeSH
- dospělí MeSH
- hyperplazie diagnostické zobrazování patologie MeSH
- lidé MeSH
- mandibula patologie MeSH
- mladý dospělý MeSH
- processus condylaris mandibulae * diagnostické zobrazování chirurgie patologie MeSH
- rentgenová mikrotomografie škodlivé účinky MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- Publikační typ
- časopisecké články MeSH
In this work we have used X-ray micro-computed tomography (μCT) as a method to observe the morphology of 3D porous pure collagen and collagen-composite scaffolds useful in tissue engineering. Two aspects of visualizations were taken into consideration: improvement of the scan and investigation of its sensitivity to the scan parameters. Due to the low material density some parts of collagen scaffolds are invisible in a μCT scan. Therefore, here we present different contrast agents, which increase the contrast of the scanned biopolymeric sample for μCT visualization. The increase of contrast of collagenous scaffolds was performed with ceramic hydroxyapatite microparticles (HAp), silver ions (Ag(+)) and silver nanoparticles (Ag-NPs). Since a relatively small change in imaging parameters (e.g. in 3D volume rendering, threshold value and μCT acquisition conditions) leads to a completely different visualized pattern, we have optimized these parameters to obtain the most realistic picture for visual and qualitative evaluation of the biopolymeric scaffold. Moreover, scaffold images were stereoscopically visualized in order to better see the 3D biopolymer composite scaffold morphology. However, the optimized visualization has some discontinuities in zoomed view, which can be problematic for further analysis of interconnected pores by commonly used numerical methods. Therefore, we applied the locally adaptive method to solve discontinuities issue. The combination of contrast agent and imaging techniques presented in this paper help us to better understand the structure and morphology of the biopolymeric scaffold that is crucial in the design of new biomaterials useful in tissue engineering.
- MeSH
- biokompatibilní materiály chemie MeSH
- hydroxyapatit chemie MeSH
- kolagen chemie MeSH
- kontrastní látky MeSH
- kovové nanočástice chemie MeSH
- rentgenová mikrotomografie * MeSH
- stříbro chemie MeSH
- tkáňové podpůrné struktury chemie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The aim of this study was to compare the effect of several commercially available disinfectants on the accuracy of various types of impression materials and their compatibility with gypsum including surface quality and structure evaluation. Four alginate and three elastomeric impression materials in combination with disinfectants Aseptoprint Liquid, Zeta 7 solution, Silosept and Dentaclean Form were tested. The dimensional changes, detail reproduction, the compatibility with gypsum and surface/subsurface morphology were evaluated using light microscopy, scanning electron microscopy and micro computed tomography. Two alginate materials disinfected in Dentaclean Form exhibited the most significant differences (p<0.0001). The loss of detail on some alginate impressions in combination with this disinfectant including deterioration and change of morphology of gypsum surfaces was observed. Porosity in subsurface area and exposed large particles were detected. It was confirmed that the desired properties of impressions may be negatively affected in combination with some disinfectants.
Rentgenová výpočetní mikrotomografie (mikroCT) představuje moderní zobrazovací technologii s vysokým rozlišením umožňující detailní analýzu zobrazovaného vzorku. Nabízí jedinečný pohled na trojrozměrnou architekturu díky rozlišení na pomezí makroskopického a histologického zobrazení. V oblasti anatomické patologie mikroCT nachází uplatnění zejména při morfometrické analýze nádorů, hodnocení resekčních okrajů chirurgických vzorků či detekci metastáz v lymfatických uzlinách. Kombinace mikroCT s tradičními histopatologickými technikami a s využitím digitální 3D rekonstrukce otevírá nové možnosti při analýze komplexních patologických procesů. Přestože je tato metoda zatím převážně využívána ve výzkumu, její klinický potenciál je značný. Mezi hlavní přednosti patří neinvazivní zobrazení a možnost integrace s digitální patologií a nástroji umělé inteligence. Hlavními limitacemi v současné době zůstávají potřeba kontrastování vzorků, monochromatická povaha obrazu a vysoká radiační zátěž. Pokrok v technologickém vývoji však může tyto překážky překonat a umožnit širší využití mikroCT v rutinní klinické diagnostice. Tento článek představuje technologii mikroCT a její diagnostický potenciál v patologii, přibližuje její aplikace, výhody a omezení, a nabízí vhled do budoucí perspektivy jejího využití.
X-ray microtomography (microCT) represents a modern high-resolution imaging technology enabling detailed analysis of the tissue. It offers a unique perspective on three-dimensional architecture, bridging the gap between macroscopic and histological imaging. In anatomical pathology, microCT is particularly utilized for morphometric tumor analysis, evaluation of surgical specimen resection margins, and detection of metastases in lymph nodes. The combination of microCT with traditional histopathological techniques, and with digital 3D reconstructions, opens new avenues for analyzing complex pathological processes. Although this method is currently used in research, its clinical potential is significant. Key advantages include non-invasive imaging and the ability to be integrated with digital pathology and artificial intelligence tools. Current limitations include the need for sample contrast enhancement, the monochromatic nature of the images, and high radiation exposure. Advances in technological development, however, may overcome these barriers and enable the broader adoption of microCT in routine clinical diagnostics. This article explores the diagnostic potential of microCT in pathology, highlighting its applications, advantages, and limitations, while offering insights into current capabilities and future perspectives of this technology.
3D imaging approaches based on X-ray microcomputed tomography (microCT) have become increasingly accessible with advancements in methods, instruments and expertise. The synergy of material and life sciences has impacted biomedical research by proposing new tools for investigation. However, data sharing remains challenging as microCT files are usually in the range of gigabytes and require specific and expensive software for rendering and interpretation. Here, we provide an advanced method for visualisation and interpretation of microCT data with small file formats, readable on all operating systems, using freely available Portable Document Format (PDF) software. Our method is based on the conversion of volumetric data into interactive 3D PDF, allowing rotation, movement, magnification and setting modifications of objects, thus providing an intuitive approach to analyse structures in a 3D context. We describe the complete pipeline from data acquisition, data processing and compression, to 3D PDF formatting on an example of craniofacial anatomical morphology in the mouse embryo. Our procedure is widely applicable in biological research and can be used as a framework to analyse volumetric data from any research field relying on 3D rendering and CT-biomedical imaging.
- MeSH
- anatomické modely MeSH
- automatizované zpracování dat MeSH
- komprese dat statistika a číselné údaje MeSH
- lebka anatomie a histologie embryologie MeSH
- myši MeSH
- obličejové kosti anatomie a histologie embryologie MeSH
- rentgenová mikrotomografie statistika a číselné údaje MeSH
- rentgenový obraz - interpretace počítačová MeSH
- šíření informací metody MeSH
- software * MeSH
- zobrazování trojrozměrné statistika a číselné údaje MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The purpose of the study was to discover a way to study the internal structure and evolution of human embryos noninvasively. The human embryo was stained with phosphotungstic acid solution (PTA) in ethanol (EPTA) and scanned using a micro computed tomography (micro-CT) scanner. Using appropriate software, a three-dimensional image of the embryo was created, which could be further exploited. The methodology described could be used for the non-destructive examination of the internal structure of the human embryo, and the resulting data can be used as a resource for medical students, gynaecologists, and paediatricians.
- MeSH
- lidé MeSH
- plod diagnostické zobrazování MeSH
- rentgenová mikrotomografie metody MeSH
- zobrazování trojrozměrné * metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Mineralization of hydrogel biomaterials is desirable to improve their suitability as materials for bone regeneration. In this study, gellan gum (GG) hydrogels were formed by simple mixing of GG solution with bioactive glass microparticles of 45S5 composition, leading to hydrogel formation by ion release from the amorphous bioactive glass microparticles. This resulted in novel injectable, self-gelling composites of GG hydrogels containing 20% bioactive glass. Gelation occurred within 20 min. Composites containing the standard 45S5 bioactive glass preparation were markedly less stiff. X-ray microcomputed tomography proved to be a highly sensitive technique capable of detecting microparticles of diameter approximately 8 μm, that is, individual microparticles, and accurately visualizing the size distribution of bioactive glass microparticles and their aggregates, and their distribution in GG hydrogels. The widely used melt-derived 45S5 preparation served as a standard and was compared with a calcium-rich, sol-gel derived preparation (A2), as well as A2 enriched with zinc (A2Zn5) and strontium (A2Sr5). A2, A2Zn, and A2Sr bioactive glass particles were more homogeneously dispersed in GG hydrogels than 45S5. Composites containing all four bioactive glass preparations exhibited antibacterial activity against methicillin-resistant Staphylococcus aureus. Composites containing A2Zn5 and A2Sr5 bioactive glasses supported the adhesion and growth of osteoblast-like cells and were considerably more cytocompatible than 45S5. All composites underwent mineralization with calcium-deficient hydroxyapatite upon incubation in simulated body fluid. The extent of mineralization appeared to be greatest for composites containing A2Zn5 and 45S5. The results underline the importance of the choice of bioactive glass when preparing injectable, self-gelling composites.
- MeSH
- antibakteriální látky farmakologie MeSH
- bakteriální polysacharidy farmakologie MeSH
- hydrogely farmakologie MeSH
- injekce MeSH
- ionty MeSH
- keramika farmakologie MeSH
- lidé MeSH
- methicilin rezistentní Staphylococcus aureus účinky léků MeSH
- mikrobiální testy citlivosti MeSH
- nádorové buněčné linie MeSH
- rentgenová mikrotomografie * MeSH
- sklo MeSH
- spektroskopie infračervená s Fourierovou transformací MeSH
- stroncium chemie MeSH
- zinek chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Pigs are frequently used as animal models in experimental medicine. To identify processes of vascular development or regression, vascular elements must be recognised and quantified in a three-dimensional (3D) arrangement. Vascular corrosion casts enable the creation of 3D replicas of vascular trees. The aim of our study was to identify suitable casting media and optimise the protocol for porcine liver vascular corrosion casting. MATERIALS AND METHODS: Mercox II (Ladd Research, Williston, Vermont, USA) and Biodur E20 Plus (Biodur Products, Heidelberg, Germany) were tested in 4 porcine livers. The resins (volume approximately 700 mL) were injected via the portal vein. Corrosion casts were examined by macro-computed tomography, micro-computed tomography and scanning electron microscopy. RESULTS: For hepatectomies, the operating protocol was optimised to avoid gas or blood clot embolisation. We present a protocol for porcine liver vascular bed casting based on corrosion specimens prepared using Biodur E20 epoxy resin. CONCLUSIONS: Only Biodur E20Plus appeared to be suitable for high-volume vascular corrosion casting due to its optimal permeability, sufficient processing time and minimum fragility. Biodur E20 Plus is slightly elastic, radio-opaque and alcohol-resistant. These properties make this acrylic resin suitable for not only vascular research but also teaching purposes.
BACKGROUND: Collagen-based scaffolds provide a promising option for the treatment of bone defects. One of the key parameters of such scaffolds consists of porosity, including pore size. However, to date, no agreement has been found with respect to the methodology for pore size evaluation. Since the determination of the exact pore size value is not possible, the comparison of the various methods applied is complicated. Hence, this study focuses on the comparison of two widely-used methods for the characterization of porosity-scanning electron microscopy (SEM) and micro-computed tomography (micro-CT). METHODS: 7 types of collagen-based composite scaffold models were prepared by means of lyophilization and collagen cross-linking. Micro-CT analysis was performed in 3D and in 2D (pore size parameters were: major diameter, mean thickness, biggest inner circle diameter and area-equivalent circle diameter). Afterwards, pore sizes were analyzed in the same specimens by an image analysis of SEM microphotographs. The results were statistically evaluated. The comparison of the various approaches to the evaluation of pore size was based on coefficients of variance and the semi-quantitative assessment of selected qualities (e.g. the potential for direct 3D analysis, whole specimen analysis, non-destructivity). RESULTS: The pore size values differed significantly with respect to the parameters applied. Median values of pore size values were ranging from 20 to 490 µm. The SEM values were approximately 3 times higher than micro-CT 3D values for each specimen. The Mean thickness was the most advantageous micro-CT 2D approach. Coefficient of variance revealed no differences among pore size parameters (except major diameter). The semi-quantitative comparison approach presented pore size parameters in descending order with regard to the advantages thereof as follows: (1) micro-CT 3D, (2) mean thickness and SEM, (3) biggest inner circle diameter, major diameter and area equivalent circle diameter. CONCLUSION: The results indicated that micro-CT 3D evaluation provides the most beneficial overall approach. Micro-CT 2D analysis (mean thickness) is advantageous in terms of its time efficacy. SEM is still considered as gold standard for its widespread use and high resolution. However, exact comparison of pore size analysis in scaffold materials remains a challenge.
Patient-specific approach is gaining a wide popularity in computational simulations of biomechanical systems. Simulations (most often based on the finite element method) are to date routinely created using data from imaging devices such as computed tomography which makes the models seemingly very complex and sophisticated. However, using a computed tomography in finite element calculations does not necessarily enhance the quality or even credibility of the models as these depend on the quality of the input images. Low-resolution (medical-)CT datasets do not always offer detailed representation of trabecular bone in FE models and thus might lead to incorrect calculation of mechanical response to external loading. The effect of image resolution on mechanical simulations of bone-implant interaction has not been thoroughly studied yet. In this study, the effect of image resolution on the modeling procedure and resulting mechanical strains in bone was analyzed on the example of cranial implant. For this purpose, several finite element models of bone interacting with fixation-screws were generated using seven computed tomography datasets of a bone specimen but with different image resolutions (ranging from micro-CT resolution of 25 μm to medical-CT resolution of 1250 μm). The comparative analysis revealed that FE models created from images of low resolution (obtained from medical computed tomography) can produce biased results. There are two main reasons: 1. Medical computed tomography images do not allow generating models with complex trabecular architecture which leads to substituting of the intertrabecular pores with a fictitious mass; 2. Image gray value distribution can be distorted resulting in incorrect mechanical properties of the bone and thus in unrealistic or even completely fictitious mechanical strains. The biased results of calculated mechanical strains can lead to incorrect conclusion, especially when bone-implant interaction is investigated. The image resolution was observed not to significantly affect stresses in the fixation screw itself; however, selection of bone material representation might result in significantly different stresses in the screw.
