OBJECTIVES: Chemical Shift Encoded Magnetic Resonance Imaging (CSE-MRI)-based quantification of low-level (< 5% of proton density fat fraction-PDFF) fat infiltration requires highly accurate data reconstruction for the assessment of hepatic or pancreatic fat accumulation in diagnostics and biomedical research. MATERIALS AND METHODS: We compare three software tools available for water/fat image reconstruction and PDFF quantification with MRS as the reference method. Based on the algorithm exploited in the tested software, the accuracy of fat fraction quantification varies. We evaluate them in phantom and in vivo MRS and MRI measurements. RESULTS: The signal model of Intralipid 20% emulsion used for phantoms was established for 3 T and 9.4 T fields. In all cases, we noticed a high coefficient of determination (R-squared) between MRS and MRI-PDFF measurements: in phantoms <0.9924-0.9990>; and in vivo <0.8069-0.9552>. Bland-Altman analysis was applied to phantom and in vivo measurements. DISCUSSION: Multi-echo MRI in combination with an advanced algorithm including multi-peak spectrum modeling appears as a valuable and accurate method for low-level PDFF quantification over large FOV in high resolution, and is much faster than MRS methods. The graph-cut algorithm (GC) showed the fewest water/fat swaps in the PDFF maps, and hence stands out as the most robust method of those tested.

• MeSH
• algoritmy MeSH
• dospělí MeSH
• emulze MeSH
• fantomy radiodiagnostické MeSH
• játra diagnostické zobrazování   MeSH
• lidé MeSH
• magnetická rezonanční spektroskopie metody   MeSH
• počítačové zpracování obrazu metody   MeSH
• software MeSH
• tuková tkáň diagnostické zobrazování   MeSH
• voda MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH

Composite materials based on a polyamide fabric (aramid) and a polydymethylsiloxane (PDMS) matrix were designed for application in bone surgery. In order to increase the bioactivity, 2, 5, 10, 15, 20, and 25 vol.% of nano/micro hydroxyapatite (HA) and tricalcium phosphate (TCP) were added. We studied the effect of the additives on the biocompatibility of the composite. It appears that nano additives have a more favorable effect on mechanical properties than microparticles. 15 vol.% of nano hydroxyapatite additive is an optimum amount for final application of the composites as substitutes for bone tissue: in this case both the mechanical properties and the biological properties are optimized without distinct changes in the inner structure of the composite.

• MeSH
• apatity MeSH
• dimethylpolysiloxany MeSH
• fosforečnany vápenaté MeSH
• hydroxyapatit MeSH
• kosti a kostní tkáň chirurgie   MeSH
• kostní náhrady chemie   normy   MeSH
• králíci MeSH
• krevní plazma MeSH
• lidé MeSH
• mikroskopie elektronová rastrovací MeSH
• mikrotechnologie MeSH
• nanostruktury MeSH
• nylony MeSH
• osteointegrace fyziologie   MeSH
• polymery MeSH
• povrchové vlastnosti MeSH
• pružnost MeSH
• software MeSH
• testování materiálů metody   MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND AND OBJECTIVE: We present a fully automatic system based on learning approaches, which aims to localization and identification (labeling) of vertebrae in 3D computed tomography (CT) scans of possibly incomplete spines in patients with bone metastases and vertebral compressions. METHODS: The framework combines a set of 3D algorithms for i) spine detection using a convolution neural network (CNN) ii) spinal cord tracking based on combination of a CNN and a novel growing sphere method with a population optimization, iii) intervertebral discs localization using a novel approach of spatially variant filtering of intensity profiles and iv) vertebra labeling using a CNN-based classification combined with global dynamic optimization. RESULTS: The proposed algorithm has been validated in testing databases, including also a publicly available dataset. The mean error of intervertebral discs localization is 4.4 mm, and for vertebra labeling, the average rate of correctly identified vertebrae is 87.1%, which can be considered a good result with respect to the large share of highly distorted spines and incomplete spine scans. CONCLUSIONS: The proposed framework, which combines several advanced methods including also three CNNs, works fully automatically even with incomplete spine scans and with distorted pathological cases. The achieved results allow including the presented algorithms as the first phase to the fully automated computer-aided diagnosis (CAD) system for automatic spine-bone lesion analysis in oncological patients.

• MeSH
• algoritmy MeSH
• databáze faktografické MeSH
• diagnóza počítačová MeSH
• lidé MeSH
• metastázy nádorů MeSH
• meziobratlová ploténka diagnostické zobrazování   patologie   MeSH
• nádory kostí diagnostické zobrazování   patologie   MeSH
• nemoci páteře diagnostické zobrazování   MeSH
• neuronové sítě MeSH
• páteř diagnostické zobrazování   patologie   MeSH
• počítačová rentgenová tomografie * MeSH
• počítačové zpracování obrazu MeSH
• reprodukovatelnost výsledků MeSH
• rozpoznávání automatizované MeSH
• software MeSH
• zobrazování trojrozměrné metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

PURPOSE: Recent studies describe significant rates of heterotopic ossification (HO) after cervical total disc replacement (CTDR). Little is known about the reasons, and one aspect that requires further in vivo investigation is the biomechanical alteration after CTDR and the role of the implant-related centre of rotation (CORi) in particular. The role of the sagittal position of the CORi on functional outcome in two versions of a semi-constrained disc prosthesis with sagittally different CORi is the topic of this study. METHODS: Patients were candidates for single-level CTDR between C3 and C7 who suffered from CDDD and received a standard or flat version of activ C™ (Aesculap AG, Tuttlingen). Clinical and radiographic assessments were determined preoperatively, intraoperatively, at discharge and again at 6 weeks, 6 months, 1 and 2 years. Radiographic examinations were performed independently using specialized quantitative motion analysis software. RESULTS: Clinical outcome improved significantly regarding NDI as well as VAS on neck and arm pain with no differences in mean improvement by study group. Segmental angle measures show a significantly better lordotic alignment for both groups after surgery, but the degree of correction achieved is higher in the flat group. Correlation analysis proves that the more anterior the CORi is positioned, the higher the lordotic correction is achieved (Pearson rho -0.385). Segmental ROM decreased in the standard group but was maintained for flat implants. At present, our data do not demonstrate a correlation between CORi and ROM at 2 years. Two years after surgery, severe HO grade III-IV was present in 31.6 % standard and 13.1 % flat cases with significant differences. Grouping according to HO severity showed comparable sagittal positions of CORi for flat implants but a more posterior position in the severe HO group for standard implants. CONCLUSIONS: Our results confirm the influence of CORi location on segmental alignment, kinematics and HO for a semi-constrained CTDR, but it also indicates a multifactorial process.

• MeSH
• artroplastika meziobratlové ploténky MeSH
• dospělí MeSH
• heterotopická osifikace etiologie   MeSH
• krční obratle radiografie   chirurgie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• lordóza radiografie   MeSH
• meziobratlová ploténka radiografie   chirurgie   MeSH
• následné studie MeSH
• prospektivní studie MeSH
• stupeň závažnosti nemoci MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

There are only few studies concerning about long-term effect of growth hormone (GH) replacement therapy on bone mineral density and bone microstructure. To assess effect of GH replacement therapy on bone mineral density (BMD) and trabecular bone score (TBS) in adult GH deficient (AGHD) subjects over period of 10 years. From 2005 to 2018, a prospective study of AGHD patients was conducted in national referral center for treatment of GHD. All patients received subcutaneous recombinant human GH in an IGF 1-normalizing regimen once a day. Lumbar spine (L-spine) and total hip (TH) BMD using Hologic densitometers were measured at baseline and every two years during treatment with rhGH. TBS was derived from L1-L4 DXA using iNsight® software (Medimaps, France) at each time point. Periods of measurement were baseline, year 2; 4; 6; 8 and 10. In total, 63 patients (38 males, 25 females, mean age 25.1±16 years) were included in the study. After 10 years of GH treatment, IGF-1 significantly increased (~35 %), with greatest increase at year 2. During 10-year follow-up, L-spine BMD increased approximately of 7 % (NS). TH BMD increase of 11 % during follow-up (p=0.0003). The greatest increment of BMD was achieved at year 6 on both sites, L-spine (+6 %) and TH BMD (+13 %) (p<0.05). There was no significant change of TBS during whole follow-up. In this study, sustaining positive effect of GH replacement therapy on bone density in subjects with adult GH deficiency over 10 years of follow-up was observed. The study did not show effect on TBS, as indirect measure of trabecular bone microarchitecture.

• MeSH
• dítě MeSH
• dospělí MeSH
• hormonální substituční terapie MeSH
• kostní denzita účinky léků   MeSH
• lidé MeSH
• lidský růstový hormon farmakologie   terapeutické užití   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• následné studie MeSH
• prospektivní studie MeSH
• růstový hormon nedostatek   MeSH
• trabekulární kostní tkáň účinky léků   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Osteoporosis is an increasingly widespread disease, as well as diabetes mellitus. It is now accepted that osteoporotic fractures are a serious co-morbidity and complication of diabetes. Despite of good bone mineral density in Type 2 Diabetes (T2DM) patients is the fracture risk elevated. It is due to reduced bone quality. To determine the effect of glycemic compensation on bone density and trabecular bone score (TBS) in T2DM. We analyzed a cohort of 105 postmenopausal women with T2DM. For all patients, central bone density (spinal and lumbar spine) was tested by DXA methodology, glycemic control parameters were assessed, and anthropometric parameters were measured. Bone quality was analyzed using TBS software. The results were statistically processed. Good glycemic compensation with glycated hemoglobin (A1c) value <7.0 % DCCT did not lead to BMD changes in patients with T2DM. However, patients with HbA1c <7 % DCCT had significantly better TBS (1.254±0.148 vs. 1.166±0.094, p=0.01). There was a negative correlation between TBS and glycated hemoglobin (r= -0,112, p<0.05) with glycemic fasting (r= -0.117, p<0.05). The optimal effect on TBS is achieved when all three markers of glycemic compensation (glycated hemoglobin, fasting plasma glucose and postprandial glycemia) are in optimal range. By using ROC curves glycated hemoglobin has the most significant effect on TBS. Optimal glycemic compensation, evaluated by glycated hemoglobin, does not lead to changes in BMD but has a beneficial effect on TBS in T2DM. Good glycemic control is required also for reduction of the risk of osteoporosis and osteoporotic fractures.

• MeSH
• diabetes mellitus 2. typu krev   farmakoterapie   patologie   MeSH
• glykovaný hemoglobin metabolismus   MeSH
• hypoglykemika farmakologie   terapeutické užití   MeSH
• kombinovaná farmakoterapie MeSH
• kostní denzita * MeSH
• lidé středního věku MeSH
• lidé MeSH
• metformin farmakologie   terapeutické užití   MeSH
• postmenopauza MeSH
• průřezové studie MeSH
• sitagliptin fosfát farmakologie   terapeutické užití   MeSH
• trabekulární kostní tkáň účinky léků   patologie   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Laser therapy has emerged as a promising treatment modality for improving the appearance and symptoms associated with hypertrophic and keloid scars. In this network meta-analysis, we aimed to evaluate the efficacy of different laser types in treating hypertrophic and keloid scars. METHODS: A comprehensive search of four databases was conducted to identify relevant studies published up until July 2023. Data were extracted from eligible studies and pooled as mean difference (MD) for continuous outcomes and risk ratio (RR) for dichotomous data in a network meta-analysis (NMA) model, using R software. RESULTS: A total of 18 studies, comprising 550 patients, were included in the analysis. Pooling our data showed that fractional carbon dioxide (FCO2) plus 5-fluorouracil (5-FU) was superior to control in terms of Vancouver Scar Scale (VSS), pliability score, and thickness; [MD = - 5.97; 95% CI (- 7.30; - 4.65)], [MD = - 2.68; 95% CI (- 4.03; - 1.33)], [MD = - 2.22; 95% CI (- 3.13; - 1.31)], respectively. However, insignificant difference was observed among FCO2 plus 5-FU compared to control group in terms of erythema, vascularity, redness and perfusion, and pigmentation [MD = - 0.71; 95% CI (- 2.72; 1.30)], [MD = - 0.44; 95% CI (- 1.26; 0.38)], respectively. CONCLUSION: Our NMA found that the FCO2 plus 5-FU was the most effective intervention in decreasing the VSS and thickness, while FCO2 plus CO2 was the most effective intervention in decreasing the pliability score. Further research is needed to determine the optimal laser parameters and long-term efficacy of laser therapy in hypertrophic and keloid scars. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

• MeSH
• jizva hypertrofická * diagnóza   terapie   MeSH
• keloid * diagnóza   terapie   MeSH
• laserová terapie škodlivé účinky   přístrojové vybavení   metody   MeSH
• lidé MeSH
• síťová metaanalýza MeSH
• výsledek terapie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• metaanalýza MeSH
• systematický přehled MeSH