R162: CT Analysis of the Frontal Recess Region in Normal Chinese

Abstract Introduction For successful intramedullary implant placement at the femur, such as nailing in unstable proximal femur fractures, the use of an implant that at least reaches or exceeds the femoral isthmus and yields sufficient thickness is recommended. A number of complications after intramedullary femoral nailing have been reported, particularly in Asians. To understand the anatomical features of the proximal femur and their ethnic differences, we aimed to accurately calculate the femoral isthmus dimensions and proximal distance of Asians and Caucasians. Methods In total, 1189 Asian and Caucasian segmented 3D CT data sets of femurs were analyzed. The individual femoral isthmus diameter was precisely computed to investigate whether gender, femur length, age, ethnicity or body mass index have an influence on isthmus diameters. Results The mean isthmus diameter of all femurs was 10.71 ± 2.2 mm. A significantly larger diameter was found in Asians when compared to Caucasians (p < 0.001). Age was a strong predictor of the isthmus diameter variability in females (p < 0.001, adjusted r2 = 0.299). With every year of life, the isthmus showed a widening of 0.08 mm in women. A Matched Pair Analysis of 150 female femurs showed a significant difference between isthmus diameter in Asian and Caucasian femurs (p = 0.05). In 50% of the cases the isthmus was found in a range of 2.4 cm between 16.9 and 19.3 cm distal to the tip of the greater trochanter. The female Asian femur differs from Caucasians as it is wider at the isthmus. Conclusions In absolute values, the proximal isthmus distance did not show much variation but is more proximal in Asians. The detailed data presented may be helpful in the development of future implant designs. The length and thickness of future standard implants may be considered based on the findings.

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Micro‐CT analysis of the Lisfranc complex reveals higher bone mineral density in dorsal compared to plantar regions

Journal of Orthopaedic Research® ◽

10.1002/jor.25164 ◽

2021 ◽

Author(s):

Melissa R. Requist ◽

Yantarat Sripanich ◽

Tim Rolvien ◽

Amy L. Lenz ◽

Alexej Barg

Keyword(s):

Bone Mineral Density ◽

Bone Mineral ◽

Micro Ct ◽

Mineral Density ◽

Ct Analysis

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Loss of Wnt16 Leads to Skeletal Deformities and Downregulation of Bone Developmental Pathway in Zebrafish

International Journal of Molecular Sciences ◽

10.3390/ijms22136673 ◽

2021 ◽

Vol 22 (13) ◽

pp. 6673

Author(s):

Xiaochao Qu ◽

Mei Liao ◽

Weiwei Liu ◽

Yisheng Cai ◽

Qiaorong Yi ◽

...

Keyword(s):

Gene Knockout ◽

Integration Site ◽

Skeletal Development ◽

Rna Seq ◽

Developmental Pathway ◽

Mineral Density ◽

Zebrafish Model ◽

Protein Protein Interaction ◽

Ct Analysis

Wingless-type MMTV integration site family, member 16 (wnt16), is a wnt ligand that participates in the regulation of vertebrate skeletal development. Studies have shown that wnt16 can regulate bone metabolism, but its molecular mechanism remains largely undefined. We obtained the wnt16-/- zebrafish model using the CRISPR-Cas9-mediated gene knockout screen with 11 bp deletion in wnt16, which led to the premature termination of amino acid translation and significantly reduced wnt16 expression, thus obtaining the wnt16-/- zebrafish model. The expression of wnt16 in bone-related parts was detected via in situ hybridization. The head, spine, and tail exhibited significant deformities, and the bone mineral density and trabecular bone decreased in wnt16-/- using light microscopy and micro-CT analysis. RNA sequencing was performed to explore the differentially expressed genes (DEGs). Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis found that the down-regulated DEGs are mainly concentrated in mTOR, FoxO, and VEGF pathways. Protein–protein interaction (PPI) network analysis was performed with the detected DEGs. Eight down-regulated DEGs including akt1, bnip4, ptena, vegfaa, twsg1b, prkab1a, prkab1b, and pla2g4f.2 were validated by qRT-PCR and the results were consistent with the RNA-seq data. Overall, our work provides key insights into the influence of wnt16 gene on skeletal development.

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Automated quantitative thin slice volumetric low dose CT analysis predicts disease severity in COVID-19 patients

Clinical Imaging ◽

10.1016/j.clinimag.2021.04.008 ◽

2021 ◽

Author(s):

Mircea Gabriel Stoleriu ◽

Michael Gerckens ◽

Florian Obereisenbuchner ◽

Iva Zaimova ◽

Justin Hetrodt ◽

...

Keyword(s):

Disease Severity ◽

Low Dose ◽

Low Dose Ct ◽

Thin Slice ◽

Ct Analysis

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A Micro-Computed Tomography Comparison of the Porosity in Additively Fabricated CuCr1 Alloy Parts Using Virgin and Surface-Modified Powders

Materials ◽

10.3390/ma14081995 ◽

2021 ◽

Vol 14 (8) ◽

pp. 1995

Author(s):

Mirko Sinico ◽

Suraj Dinkar Jadhav ◽

Ann Witvrouw ◽

Kim Vanmeensel ◽

Wim Dewulf

Keyword(s):

High Energy ◽

High Energy Density ◽

Micro Ct ◽

Micro Computed Tomography ◽

Powder Bed ◽

Metallurgical Defects ◽

Ct Analysis ◽

Ct Data ◽

Surface Modified ◽

Fusion Pores

Recently, the use of novel CuCr1 surface-modified powder for reliable laser powder-bed fusion (LPBF) manufacturing has been proposed, enabling a broader LPBF processing window and longer powder storage life. Nevertheless, virgin CuCr1 powder is also LPBF processable, on the condition that a high-energy density is employed. In this work, we compare two dense specimens produced from virgin and surface-modified CuCr1 powder. Furthermore, a third sample fabricated from surface-modified powder is characterized to understand an abnormal porosity content initially detected through Archimedes testing. Utilizing high-resolution micro-CT scans, the nature of the defects present in the different samples is revealed. Pores are analyzed in terms of size, morphology and spatial distribution. The micro-CT data reveal that the virgin CuCr1 dense specimen displays keyhole pores plus pit cavities spanning multiple layer thicknesses. On the other hand, the sample fabricated with the surface-modified CuCr1 powder mainly contains small and spherical equi-distributed metallurgical defects. Finally, the CT analysis of the third specimen reveals the presence of a W contamination, favoring lack-of-fusion pores between subsequent LPBF layers. The LPBF melting mode (keyhole or conductive), the properties of the material, and the potential presence of contaminants are connected to the different porosity types and discussed.

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Supratubal recess and sinus tympani: CT analysis of middle ear hidden areas

Egyptian Journal of Radiology and Nuclear Medicine ◽

10.1186/s43055-019-0056-1 ◽

2019 ◽

Vol 50 (1) ◽

Cited By ~ 1

Author(s):

Mohammad Waheed El-Anwar ◽

Diaa Bakry Eldib ◽

Ashraf Elmalt ◽

Alaa Omar Khazbak

Keyword(s):

Middle Ear ◽

Preoperative Imaging ◽

High Resolution Computed Tomography ◽

Sinus Tympani ◽

Ct Analysis ◽

Length Width ◽

Middle Ear Anatomy ◽

Grade 3 ◽

Temporal Bones ◽

Ct Classification

Abstract Background High-resolution computed tomography (HRCT) magnifies the role of preoperative imaging for detailed middle ear anatomy particularly its hidden area. The purpose of the current study was to assess the sinus tympani (ST) and supratubal recess (STR) by HRCT, to create CT classification of the STR depth, and to study the relationship between ST types and the new STR grades. Results In HRCT of non-pathological temporal bones of 100 subjects (200 ears), measurements of the STR and ST were calculated, registered, and analyzed. The depth of the STR was classified into grade 1 with depth less than 3 mm, grade 2 with depth ranged between 3 and 5 mm, and grade 3 with depth more than 5 mm. The mean STR length, width, and height were 4.17 ± 0.86, 3.55 ± 0.65, and 3.64 ± 0.7 mm, respectively, while the ST mean length and width of were 2.52 ± 0.5 and 1.82 ± 0.78 mm, respectively, without significant differences between either sexes or sided. The ST types were found to be type A in 56 ears (28%), type B in 142 ears (71%), and type C in 2 ears (1%). The STR grading was grade 1 in 12 ears (6%), grade 2 in 160 ears (80%), and grade 3 in 28 ears (14%) without significant relationship between ST types and STR grading (P = 0.3). Conclusion The current study provided reliable and applicable methods of CT assessment of STR and ST that can help to predict the degree of surgical visibility of the ST and STR during ear surgery.

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