Anatomic study of fibrous structures attached to the volar ulnar corner of the radius: implications in the volar rim fracture

2021 ◽  
pp. 175319342098219
Author(s):  
Natsumi Saka ◽  
Akimoto Nimura ◽  
Masahiro Tsutsumi ◽  
Taiki Nozaki ◽  
Yoshinobu Watanabe ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Soft Tissue ◽  
Healthy Volunteers ◽  
Distal Radius ◽  
Dorsal Side ◽  
Micro Computed Tomography ◽  
Anatomic Study ◽  
Ulnar Styloid ◽  
Mri Studies

This study aimed to clarify the bone and soft tissue morphological features at the volar ulnar corner of the radius. Micro-computed tomography, macroscopic and histological analyses were conducted using 12 cadaveric wrists, and in vivo MRI studies of the wrist were evaluated in five healthy volunteers. The volar ulnar corner of the distal radius has a protrusion volar to the sigmoid notch. The capsule elements of the radiolunate and radioulnar joints merge and this conjoined capsule attaches to the radius at the ulnar protrusion. Histologically, this capsule attaches to the radius via fibrocartilage, with fibres running in the radioulnar direction. In-vivo MRI studies showed that the capsule attaching to the volar ulnar corner could be traced to the dorsal side of the ulnar styloid. Our findings indicate that, given the direction of the fibres, an avulsion force in the radioulnar direction could be a cause for volar rim fractures.

Demineralized bone matrix-based microcarrier scaffold favors vascularized large bone regeneration in vivo in a rat model

2018 ◽  
Vol 33 (2) ◽  
pp. 182-195 ◽  
Author(s):  
Qiannan Li ◽  
Wenjie Zhang ◽  
Guangdong Zhou ◽  
Yilin Cao ◽  
Wei Liu ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Stem Cells ◽  
Bone Marrow ◽  
Bone Regeneration ◽  
Demineralized Bone Matrix ◽  
Bone Matrix ◽  
Matrix Group ◽  
Micro Computed Tomography ◽  
Demineralized Bone

Insufficient neo-vascularization of in vivo implanted cell-seeded scaffold remains a major bottleneck for clinical translation of engineered bone formation. Demineralized bone matrix is an ideal bone scaffold for bone engineering due to its structural and biochemical components similar to those of native bone. We hypothesized that the microcarrier form of demineralized bone matrix favors ingrowth of vessels and bone regeneration upon in vivo implantation. In this study, a rat model of femoral vessel pedicle-based bone engineering was employed by filling the demineralized bone matrix scaffolds inside a silicone chamber that surrounded the vessel pedicles, and to compare the efficiency of vascularized bone regeneration between microcarrier demineralized bone matrix and block demineralized bone matrix. The results showed that bone marrow stem cells better adhered to microcarrier demineralized bone matrix and produced more extracellular matrices during in vitro culture. After in vivo implantation, microcarrier demineralized bone matrix seeded with bone marrow stem cells formed relatively more bone tissue than block demineralized bone matrix counterpart at three months upon histological examination. Furthermore, micro-computed tomography three-dimensional reconstruction showed that microcarrier demineralized bone matrix group regenerate significantly better and more bone tissues than block demineralized bone matrix both qualitatively and quantitatively (p < 0.05). Moreover, micro-computed tomography reconstructed angiographic images also demonstrated significantly enhanced tissue vascularization in microcarrier demineralized bone matrix group than in block demineralized bone matrix group both qualitatively and quantitatively (p < 0.05). Anti-CD31 immunohistochemical staining of (micro-) vessels and semi-quantitative analysis also evidenced enhanced vascularization of regenerated bone in microcarrier demineralized bone matrix group than in block demineralized bone matrix group (p < 0.05). In conclusion, the microcarrier form of demineralized bone matrix is an ideal bone regenerative scaffold due to its advantages of osteoinductivity and vascular induction, two essentials for in vivo bone regeneration.

scholarly journals Combined visualization of echinoderm hard and soft parts using contrast-enhanced micro-computed tomography

Zoosymposia ◽  
2019 ◽  
Vol 15 (1) ◽  
pp. 172-191 ◽  
Author(s):  
ALEXANDER ZIEGLER
Keyword(s):  
Computed Tomography ◽  
Soft Tissue ◽  
3D Visualization ◽  
Soft Part ◽  
Three Dimensional ◽  
Ethanol Solution ◽  
Micro Computed Tomography ◽  
Soft Tissue Contrast ◽  
Contrast Enhanced ◽  
Tissue Contrast

Recent studies have shown that micro-computed tomography (µCT) must be considered one of the most suitable techniques for the non-invasive, three-dimensional (3D) visualization of metazoan hard parts. In addition, µCT can also be used to visualize soft part anatomy non-destructively and in 3D. In order to achieve soft tissue contrast using µCT based on X-ray attenuation, fixed specimens must be immersed in staining solutions that include heavy metals such as silver (Ag), molybdenum (Mo), osmium (Os), lead (Pb), or tungsten (W). However, while contrast-enhancement has been successfully applied to specimens pertaining to various higher metazoan taxa, echinoderms have thus far not been analyzed using this approach. In order to demonstrate that this group of marine invertebrates is suitable for contrast-enhanced µCT as well, the present study provides results from an application of this technique to representative species from all five extant higher echinoderm taxa. To achieve soft part contrast, freshly fixed and museum specimens were immersed in an ethanol solution containing phosphotungstic acid and then scanned using a high-resolution desktop µCT system. The acquired datasets show that the combined visualization of echinoderm soft and hard parts can be readily accomplished using contrast-enhanced µCT in all extant echinoderm taxa. The results are compared with µCT data obtained using unstained specimens, with conventional histological sections, and with data previously acquired using magnetic resonance imaging, a technique known to provide excellent soft tissue contrast despite certain limitations. The suitability for 3D visualization and modeling of datasets gathered using contrast-enhanced µCT is illustrated and applications of this novel approach in echinoderm research are discussed.

scholarly journals Intraosteal Behavior of Porous Scaffolds: The mCT Raw-Data Analysis as a Tool for Better Understanding

Symmetry ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 532 ◽  
Author(s):  
Parrilla-Almansa ◽  
González-Bermúdez ◽  
Sánchez-Sánchez ◽  
Meseguer-Olmo ◽  
Martínez-Cáceres ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Mathematical Analysis ◽  
Demineralized Bone Matrix ◽  
Bone Matrix ◽  
Hounsfield Unit ◽  
In Vivo Studies ◽  
Porous Scaffolds ◽  
Micro Computed Tomography ◽  
Radiological Analysis

The aim of the study is to determine the existing correlation between high-resolution 3D imaging technique obtained through Micro Computed Tomography (mCT) and histological-histomorphometric images to determine in vivo bone osteogenic behavior of bioceramic scaffolds. A Ca-Si-P scaffold ceramic doped and non-doped (control) with a natural demineralized bone matrix (DBM) were implanted in rabbit tibias for 1, 3, and 5 months. A progressive disorganization and disintegration of scaffolds and bone neoformation occurs, from the periphery to the center of the implants, without any differences between histomorphometric and radiological analysis. However, significant differences (p < 0.05) between DMB-doped and non-doped materials where only detected through mathematical analysis of mCT. In this way, average attenuation coefficient for DMB-doped decreased from 0.99 ± 0.23 Hounsfield Unit (HU) (3 months) to 0.86 ± 0.32 HU (5 months). Average values for non-doped decreased from 0.86 ± 0.25 HU (3 months) to 0.66 ± 0.33 HU. Combination of radiological analysis and mathematical mCT seems to provide an adequate in vivo analysis of bone-implanted biomaterials after surgery, obtaining similar results to the one provided by histomorphometric analysis. Mathematical analysis of Computed Tomography (CT) would allow the conducting of long-term duration in vivo studies, without the need for animal sacrifice, and the subsequent reduction in variability.

Feasibility, Safety, and Efficacy of Flow-Diverting Stent-Assisted Microsphere Embolization of Fusiform and Sidewall Aneurysms

Neurosurgery ◽  
2015 ◽  
Vol 77 (1) ◽  
pp. 126-136 ◽  
Author(s):  
Andrea Nonn ◽  
Stefanie Kirschner ◽  
Giovanna Figueiredo ◽  
Martin Kramer ◽  
Omid Nikoubashman ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Protection System ◽  
Micro Computed Tomography ◽  
Beam Hardening ◽  
Safety And Efficacy ◽  
Aneurysm Occlusion ◽  
Flow Diverting Stent ◽  
Microsphere Embolization

Abstract BACKGROUND: Treatment of wide-necked internal carotid artery aneurysms is frequently associated with incomplete occlusion and high recurrence rates. Furthermore, platinum coils cause strong beam-hardening artifacts, hampering subsequent image analyses. OBJECTIVE: To assess the feasibility, safety, and efficacy of flow-diverting, stent-assisted microsphere embolization of fusiform and sidewall aneurysms in vitro and in vivo. METHODS: Using a recirculating pulsatile in vitro flow model, 5 different aneurysm geometries (inner/outer curve, narrow/wide neck, and fusiform) were treated (each n = 1) by flow-diverting stent (FDS) implantation and subsequent embolization through a jailed microcatheter using calibrated microspheres (500–900 μm) larger than the pores of the FDS mesh. Treatment effects were analyzed angiographically and by micro computed tomography. The fluid of the in vitro model was filtered to ensure that no microspheres evaded the aneurysm. The experiment was repeated once in vivo. RESULTS: In vitro, all 5 aneurysms were safely and completely occluded by FDS-assisted microsphere embolization. Virtually complete aneurysm occlusion was confirmed by angiography and micro computed tomography. No microspheres escaped into the circulation. The experiment was successfully repeated in 1 pig with a sidewall aneurysm generated by vessel occlusion. An embolic protection system placed distally of the FDS in vitro and in vivo (each n = 1) contained no microspheres after the embolization. Thus, no microspheres were lost in the circulation, and the use of an embolic protection system seems feasible to provide additional safety. CONCLUSION: FDS-assisted microsphere embolization of fusiform and sidewall aneurysms is feasible and yields virtually complete aneurysm occlusion while avoiding coil-associated beam-hardening artifacts.

scholarly journals 0349 : Comparison of bioimpedance and X-ray micro-computed tomography (μCT) for total fat volume measurement in mice in vivo

2015 ◽  
Vol 7 (2) ◽  
pp. 139
Author(s):  
Gaëlle Aubertin-Kirch ◽  
Amira Sayeh ◽  
Christian Goetz ◽  
Jean-Philippe Dillenseger ◽  
Isabelle Chery ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Volume Measurement ◽  
Micro Computed Tomography ◽  
X Ray ◽  
Total Fat ◽  
Fat Volume
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