scholarly journals Generation of Vertebra Micro-CT-like Image from MDCT: A Deep-Learning-Based Image Enhancement Approach

Tomography ◽  
2021 ◽  
Vol 7 (4) ◽  
pp. 767-782
Author(s):  
Dan Jin ◽  
Han Zheng ◽  
Qingqing Zhao ◽  
Chunjie Wang ◽  
Mengze Zhang ◽  
...  
Keyword(s):  
Deep Learning ◽  
Trabecular Bone ◽  
Image Enhancement ◽  
Volume Fraction ◽  
Similarity Index ◽  
Ct Images ◽  
Micro Ct ◽  
Bone Volume Fraction ◽  
Trabecular Thickness ◽  
Significant Difference

This paper proposes a deep-learning-based image enhancement approach that can generate high-resolution micro-CT-like images from multidetector computed tomography (MDCT). A total of 12,500 MDCT and micro-CT image pairs were obtained from 25 vertebral specimens. Then, a pix2pixHD model was trained and evaluated using the structural similarity index measure (SSIM) and Fréchet inception distance (FID). We performed subjective assessments of the micro-CT-like images based on five aspects. Micro-CT and micro-CT-like image-derived trabecular bone microstructures were compared, and the underlying correlations were analyzed. The results showed that the pix2pixHD method (SSIM, 0.804 ± 0.037 and FID, 43.598 ± 9.108) outperformed the two control methods (pix2pix and CRN) in enhancing MDCT images (p < 0.05). According to the subjective assessment, the pix2pixHD-derived micro-CT-like images showed no significant difference from the micro-CT images in terms of contrast and shadow (p > 0.05) but demonstrated slightly lower noise, sharpness and trabecular bone texture (p < 0.05). Compared with the trabecular microstructure parameters of micro-CT images, those of pix2pixHD-derived micro-CT-like images showed no significant differences in bone volume fraction (BV/TV) (p > 0.05) and significant correlations in trabecular thickness (Tb.Th) and trabecular spacing (Tb.Sp) (Tb.Th, R = 0.90, p < 0.05; Tb.Sp, R = 0.88, p < 0.05). The proposed method can enhance the resolution of MDCT and obtain micro-CT-like images, which may provide new diagnostic criteria and a predictive basis for osteoporosis and related fractures.

Effects of Thresholding Techniques on μCT-Based Finite Element Models of Trabecular Bone

2006 ◽  
Vol 129 (4) ◽  
pp. 481-486 ◽  
Author(s):  
Chi Hyun Kim ◽  
Henry Zhang ◽  
George Mikhail ◽  
Dietrich von Stechow ◽  
Ralph Müller ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Finite Element ◽  
Trabecular Bone ◽  
Volume Fraction ◽  
Ct Images ◽  
Bone Volume ◽  
Finite Element Models ◽  
Micro Ct ◽  
Bone Volume Fraction ◽  
Element Analysis

Microimaging based finite element analysis is widely used to predict the mechanical properties of trabecular bone. The choice of thresholding technique, a necessary step in converting grayscale images to finite element models, can significantly influence the predicted bone volume fraction and mechanical properties. Therefore, we investigated the effects of thresholding techniques on microcomputed tomography (micro-CT) based finite element models of trabecular bone. Three types of thresholding techniques were applied to 16-bit micro-CT images of trabecular bone to create three different models per specimen. Bone volume fractions and apparent moduli were predicted and compared to experimental results. In addition, trabecular tissue mechanical parameters and morphological parameters were compared among different models. Our findings suggest that predictions of apparent mechanical properties and structural properties agree well with experimental measurements regardless of the choice of thresholding methods or the format of micro-CT images.

Non-Invasive Analysis of the Micro-Structural and Biomechanical Properties of Trabecular Bone in Human Femoral Head

2006 ◽  
Vol 321-323 ◽  
pp. 1070-1073
Author(s):  
Ye Yeon Won ◽  
Myong Hyun Baek ◽  
Wen Quan Cui ◽  
Kwang Kyun Kim
Keyword(s):  
Mechanical Properties ◽  
Mechanical Property ◽  
Femoral Head ◽  
Trabecular Bone ◽  
Volume Fraction ◽  
Reaction Force ◽  
Bone Volume ◽  
Fe Model ◽  
Micro Ct ◽  
Trabecular Thickness

This study investigates micro-structural and mechanical properties of trabecular bone in human femoral head with and without osteoporosis using a micro-CT and a finite element model. 15 cored trabecular bone specimens with 20 of diameter were obtained from femoral heads with osteoporosis resected for total hip arthroplasty, and 5 specimens were removed from femoral head of cadavers, which has no history of musculoskeletal diseases. A high-resolution micro-CT system was used to scan each specimen to obtain histomorphometry indexes. Based on the micro-images, a FE-model was created to determine mechanical property indexes. While the non-osteoporosis group had increases the trabecular thickness, the bone volume, the bone volume fraction, the degree of anisotropy and the trabecular number compared with those of osteoporotic group, the non-osteoporotic group showed decreases in trabecular separation and structure model index. Regarding the mechanical property indexes, the reaction force and the Young's modulus were lower in the osteoporotic group than in non-osteoporotic group. Our data shows salient deteriorations in trabecular micro-structural and mechanical properties in human femoral head with osteoporosis.

scholarly journals Effects of vertebroplasty on endplate subsidence in elderly female spines

2015 ◽  
Vol 22 (3) ◽  
pp. 273-282 ◽  
Author(s):  
Srinidhi Nagaraja ◽  
Hassan K. Awada ◽  
Maureen L. Dreher ◽  
John T. Bouck ◽  
Shikha Gupta
Keyword(s):  
Bone Cement ◽  
Trabecular Bone ◽  
Volume Fraction ◽  
Micro Ct ◽  
Control Groups ◽  
Bone Volume Fraction ◽  
Elderly Female ◽  
Maximum Subsidence ◽  
And Control ◽  
Adjacent Vertebra

OBJECT The aim in this study was to quantify the effects of vertebroplasty on endplate subsidence in treated and adjacent vertebrae and their relationship to endplate thickness and underlying trabecular bone in elderly female spines. METHODS Vertebral compression fractures were created in female cadaveric (age range 51–88 years) thoracolumbar spine segments. Specimens were placed into either the control or vertebroplasty group (n = 9/group) such that bone mineral density, trabecular microarchitecture, and age were statistically similar between groups. For the vertebroplasty group, polymethylmethacrylate bone cement was injected into the fractured vertebral body under fluoroscopy. Cyclic compression (685–1370 N sinusoid) was performed on all spine segments for 115,000 cycles. Micro-CT scans were obtained before and after cyclic loading to quantify endplate subsidence. Maximum subsidence was compared between groups in the caudal endplate of the superior adjacent vertebra (SVcau); cranial (TVcra) and caudal (TVcau) endplates of the treated vertebra; and the cranial endplate of the inferior adjacent vertebra (IVcra). In addition, micro-CT images were used to quantify average endplate thickness and trabecular bone volume fraction. These parameters were then correlated with maximum endplate subsidence for each endplate. RESULTS The maximum subsidence in SVcau endplate for the vertebroplasty group (0.34 ± 0.58 mm) was significantly (p < 0.05) greater than for the control group (−0.13 ± 0.27 mm). Maximum subsidence in the TVcra, TVcau, and IVcra endplates were greater in the vertebroplasty group, but these differences were not significant (p > 0.16). Increased subsidence in the vertebroplasty group manifested locally in the anterior region of the SVcau endplate and in the posterior region of the TVcra and TVcau endplates (p < 0.10). Increased subsidence was observed in thinner endplates with lower trabecular bone volume fraction for both vertebroplasty and control groups (R2 correlation up to 62%). In the SVcau endplate specifically, these 2 covariates aided in understanding subsidence differences between vertebroplasty and control groups. CONCLUSIONS Bone cement injected during vertebroplasty alters local biomechanics in elderly female spines, resulting in increased endplate disruption in treated and superior adjacent vertebrae. More specifically, bone cement increases subsidence in the posterior regions of the treated endplates and the anterior region of the superior caudal endplate. This increased subsidence may be the initial mechanism leading to subsequent compression fractures after vertebroplasty, particularly in vertebrae superior to the treated level.

scholarly journals Effects of different force magnitudes on corticotomy-assisted orthodontic tooth movement in rats

2018 ◽  
Vol 88 (5) ◽  
pp. 632-637 ◽  
Author(s):  
Kriangkrai Kraiwattanapong ◽  
Bancha Samruajbenjakun
Keyword(s):  
Alveolar Bone ◽  
Tooth Movement ◽  
Root Resorption ◽  
Volume Fraction ◽  
Micro Ct ◽  
Histomorphometric Analysis ◽  
Bone Volume Fraction ◽  
Bone Response ◽  
Significant Difference ◽  
Light Force

ABSTRACT Objectives: To investigate the effects of light and heavy forces with corticotomy on tooth movement rate, alveolar bone response, and root resorption in a rat model. Materials and Methods: The right and left sides of 40 male Wistar rats were randomly assigned using the split-mouth design to two groups: light force with corticotomy (LF) and heavy force with corticotomy (HF). Tooth movement was performed on the maxillary first molars using a nickel-titanium closed-coil spring delivering either 10 g (light force) or 50 g (heavy force). Tooth movement and alveolar bone response were assessed by micro–computed tomography (micro-CT) at day 0 as the baseline and on days 7, 14, 21, and 28. Root resorption was examined by histomorphometric analysis at day 28. Results: Micro-CT analysis showed a significantly greater tooth movement in the HF group at days 7 and 14 but no difference in bone volume fraction at any of the observed periods. Histomorphometric analysis found no significant difference in root resorption between the LF and HF groups at day 28. Conclusions: Heavy force with corticotomy increased tooth movement at days 7 and 14 but did not show any difference in alveolar bone change or root resorption.

Bone and muscle development in three inbred female mouse strains

2021 ◽  
Author(s):  
Ursula Föger-Samwald ◽  
Maria Papageorgiou ◽  
Katharina Wahl-Figlash ◽  
Katharina Kerschan-Schindl ◽  
Peter Pietschmann
Keyword(s):  
Trabecular Bone ◽  
Muscle Development ◽  
Bone Growth ◽  
Volume Fraction ◽  
Bone Structure ◽  
Bone Development ◽  
Mouse Strains ◽  
Structural Reorganization ◽  
Bone Volume Fraction ◽  
Trabecular Thickness

AbstractMuscle force is thought to be one of the main determinants of bone development. Hence, peak muscle growth is expected to precede peak bone growth. In this study, we investigated muscle and bone development in female C57BL/6 J, DBA/2JRj, and C3H/HeOuJ mice. Femoral cortical and trabecular bone structure and the weights of selected muscles were assessed at the ages of 8, 16, and 24 weeks. Muscle mass increased from 8 to 24 weeks in all 3 strains, suggesting peak muscle development at 24 weeks or later. Bone volume fraction, trabecular number, and connectivity density of the femur decreased or remained unchanged, whereas trabecular density and trabecular thickness largely increased. These results suggest a peak in trabecular bone accrual at 8 weeks or earlier followed by further increases in density and structural reorganization of trabeculae. Cortical density, cortical thickness, and cortical cross sectional area increased over time, suggesting a peak in cortical bone accrual at 24 weeks or later. In conclusion, our data provide evidence that growth of muscle lags behind trabecular bone accrual.

scholarly journals Assessment of Trabecular Bone During Dental Implant Planning using Cone-beam Computed Tomography with High-resolution Parameters

2021 ◽  
Vol 15 (1) ◽  
pp. 57-63
Author(s):  
Lauren Bohner ◽  
Pedro Tortamano ◽  
Felix Gremse ◽  
Israel Chilvarquer ◽  
Johannes Kleinheinz ◽  
...  
Keyword(s):  
Computed Tomography ◽  
High Resolution ◽  
Trabecular Bone ◽  
Cone Beam Computed Tomography ◽  
Volume Fraction ◽  
Statistical Significance ◽  
Cone Beam ◽  
Bone Volume Fraction ◽  
Voxel Size ◽  
Trabecular Thickness

Background: Cone-Beam Computed Tomography (CBCT) with high-resolution parameters may provide an acceptable resolution for bone assessment. Objectives: The purpose of this study is to assess trabecular bone using two cone-beam computed tomography (CBCT) devices with high-resolution parameters in comparison to micro-computed tomography (µCT). Methods: Bone samples (n=8) were acquired from dry mandibles and scanned by two CBCT devices: 1) VV (Veraview R100, Morita; FOV 4x4, 75kV, 9mA, voxel size 0.125µm); and PR (Prexion 3D, Prexion; FOV 5x5, 90kV, 4mA, 37s, voxel size 108µm). Gold-standard images were acquired using µCT (SkyScan 1272; Bruker; 80kV, 125mA, voxel size 16µm). Morphometric parameters (BvTv- Bone Volume Fraction, BsBv- Trabecular specific surface, TbTh- Trabecular thickness and TbSp- Trabecular separation) were measured. Statistical analysis was performed within ANOVA, Spearman Correlation test and Bland-Altmann plots with a statistical significance level at p=0.05. Results: CBCT devices showed similar BvTv values in comparison to µCT. No statistical difference was found for BvTv parameters assessed by CBCT devices and µCT. BsBv values were underestimated by CBCT devices (p<0.01), whereas TbTh and TbSp values were overestimated by them (p<0.01). Positive correlations were found between VV and µCT measurements for BvTv (r2= 0.65, p=0.00), such as between PR and µCT measurements for TbSp (r2= 0.50, p=0.04). For BsBv measurements, PR was negatively correlated with µCT (r2= -0.643, p=0.01). Conclusion: The evaluated CBCT device was able to assess trabecular bone. However, bone parameters were under or overestimated in comparison to µCT.

scholarly journals Radioprotective Effect of Sodium Selenite on Mandible of Irradiated Rats

2019 ◽  
Vol 30 (3) ◽  
pp. 232-237
Author(s):  
Mayra Cristina Yamasaki ◽  
Rocharles CavalcanteFontenele ◽  
Yuri Nejaim ◽  
Deborah Queiroz Freitas
Keyword(s):  
Sodium Selenite ◽  
Volume Fraction ◽  
Bone Microarchitecture ◽  
Bone Volume ◽  
Radioprotective Effect ◽  
Control Group ◽  
X Rays ◽  
Bone Volume Fraction ◽  
Trabecular Thickness ◽  
Significant Difference

Abstract The purpose of this study was to test the radioprotective effect of selenium in the bone microarchitecture of irradiated rats mandibles. Forty rats were separated into 4 groups with 10 animals: control group (CG), irradiated group (IG), sodium selenite group (SSG) and sodium selenite irradiated group (SSIG). A single dose of 0.8 mg/kg sodium selenite was administered intraperitoneally in the SSG and SSIG groups. One hour later, animals of IG and SSIG groups were irradiated with 15 Gy of x-rays. Forty days after radiation a bilateral extraction of the mandibular first molars was performed. After the extraction procedure, five rats were killed after fifteen days and others five after thirty days. Micro- computed tomography was used to evaluate cortical and trabecular bone of each rat. The mean and standard deviation of each bone microarchitecture parameter were analyzed using the statistical test of two-way Analysis of Variance (ANOVA). At 15 days, the bone volume presented higher values in the CG and SSG groups (p=0.001). The same groups presented statistically significant higher values when bone volume fraction (p<0.001) and trabecular thickness (p<0.001) were analyzed. At 30 days, it was observed that in relation to the bone volume fraction, SSG group presented the highest value while SSIG group had the lowest value, with statistically significant difference (p=0.016). Sodium selenite demonstrated a median radioprotective effect in the bone microarchitecture of irradiated mandibles, which indicates the substance may be a potential radioprotective agent against chronic effects of high doses of ionizing radiation.

Sign in / Sign up

Export Citation Format

Share Document