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Since the compressed sensing (CS) theory broke through the limitation of the traditional Nyquist sampling theory, it has attracted extensive attention in the field of microwave imaging. However, in 3-D microwave sparse reconstruction application, conventional CS-based algorithms always suffer from huge computational cost. In this article, a novel 3-D microwave sparse reconstruction method based on a complex-valued sparse reconstruction network (CSR-Net) is proposed, which converts complex number operations into matrix operations for real and imaginary parts. Using the unfolding + network approximate scheme, each iteration process of CS-based iterative threshold optimization is designed as a block of CSR-Net, and a modified shrinkage term is introduced to improve the convergence performance of the approach. In addition, CSR-Net adopts a convolutional neural network module to replace a nonlinear sparse representation process, which dramatically reduces computational complexity and improves reconstruction performance over conventional CS-based iterative threshold optimization algorithms. Then, we divide the 3-D scene into a series of 2-D slices, and a phase correction scheme is adopted to ensure that the whole 3-D scene can be reconstructed with measurement matrix of a slice. Moreover, an efficient position-amplitude-random training method without additional real-measured data is employed for the proposed network, which effectively train the CSR-Net without enough real-measured data. Extensive experiment results demonstrate that CSR-Net outperforms both conventional iterative threshold optimization methods and deep network-based ISTA-NET-plus large margins. Its speed and reconstruction accuracy in 3-D imaging can achieve a state-of-the-art level.

The environmental interference and the noise in 3D synthetic aperture radar (SAR) image, considered as the background, are inescapable and ought to be eliminated. For 3D SAR image, there is a spatial separation of the target and the background. Therefore, it is possible to achieve the separation of the target and the background by image segmentation. Due to the complexity of the target shape and the large dynamic range of the SAR image, the background cannot be accurately separated through the amplitude information alone. In this paper, a method based on region growing is proposed to achieve 3D SAR image background separation utilizing the plural and the spatial information. The image enhancement matrix, constructed by the plural information of the SAR image, is implemented to improve the contrast of the image. The seeds are extracted by the weighted Otsu, and the weight is determined by the structure and amplitude information from the target. For the region growing, the growing process is achieved by the accumulation of the growing rate, which can suppress the growing of the noise. During the region growing, the stopping growing condition of each seed is independent and controlled by the seed threshold. The global threshold constrains the almost unrestricted growing of the seed whose amplitude is close to the noise amplitude. The results of the simulation and the experiments verify the performance of the proposed method is higher than that of the compared methods with three image evaluation criteria. Besides, we discuss the cost of computation and the influences of three important parameters to achieve a complete analysis.

Compressed sensing (CS) algorithms are used for linear array synthetic aperture radar (LASAR) three-dimensional (3D) imaging. However, it is difficult to obtain imaging results with both high computational efficiency and promising imaging quality. Because of the high-dimensional matrix-operations, the computational complexity of several CS algorithms is huge such as the iterative adaptive approach (IAA), bayesian compressed sensing (BCS), and sparsity bayesian recovery via iterative minimum (SBRIM) algorithm. Besides, the greedy pursuit algorithms such as the orthogonal matching pursuit (OMP) algorithm cannot acquire ideal imaging results on account of the preset sparsity of the imaging scene. To solve the problem, we present a fast sparse recovery algorithm via resolution approximation (FSRARA) in this paper. Firstly, the whole imaging scene is divided into 3D scattering units with large spacing, and SBRIM algorithm is used to obtain its low-resolution imaging results quickly. Secondly, the low-resolution imaging results are conducted image segmentation by the fuzzy c-means (FCM) clustering algorithm to extract the possible targets' areas coarsely. Then we re-divide the imaging scene by higher imaging resolution and extract the possible targets' areas according to the coarsely possible targets' areas. FSRARA achieves improved computational efficiency with low-dimensional matrix-operations on the possible targets' areas instead of the high-dimensional one on the whole imaging scene. Meanwhile, FSRARA performs better in suppressing the false targets and sidelobe interference and improves the imaging quality than the SBRIM algorithm. Simulation and experimental results prove that FSRARA improves the computational efficiency by hundreds of times at most than SBRIM algorithm and its computational efficiency is higher than smoothed $L_{0} $ norm (SL0), IAA, and BCS algorithm. Besides, FSRARA improves the imaging quality compared with OMP, IAA, SL0, BCS, and SBRIM algorithms.

Most of the existing image segmentation methods have a strong anti-noise ability but are susceptible to the interference in the background, so they are not suitable for 3-D synthetic aperture radar (SAR) image target extraction. Region of interest (ROI) extraction can improve the anti-interference ability of the image segmentation methods. However, the existing ROI extraction method uses the same threshold to process all the images in the data set. This threshold is not optimal for each image. Designed for 3-D SAR image target extraction, we propose an ROI extraction algorithm with adaptive threshold (REAT) to enhance the anti-interference ability of the existing image segmentation methods. The required thresholds in the proposed algorithm are adaptively obtained by the mapping of the image features. Moreover, the proposed algorithm can easily be applied to existing image segmentation methods. The experiments demonstrate that the proposed algorithm significantly enhances the anti-interference ability and computational efficiency of the image segmentation methods. Compared with the existing ROI extraction algorithm, the proposed algorithm improves the dice similarity coefficient by 6.4%.

A novel method for synthetic aperture radar (SAR) three-dimensional (3D) sparse imaging based on a coprime linear array (CLA) is proposed. To reduce the geometric resolution loss caused by under-sampled sparse SAR, a jointed sparse imaging approach is used. In this scheme, the coprime sampled data of CLA is separately processed via the iterative reweight least-squares approach, and their recovered results are combined to cancel the false targets and grating-lobes to improve the imaging quality. Both simulated and experimented results demonstrate the effectiveness of the method. It shows that the exploiting of CLA and sparse recovery can significantly reduce the linear array antenna amount and the geometric resolution loss compared with the conventional uniform linear array SAR.

Because of the three-dimensional (3D) imaging scene’s sparsity, compressed sensing (CS) algorithms can be used for linear array synthetic aperture radar (LASAR) 3D sparse imaging. CS algorithms usually achieve high-quality sparse imaging at the expense of computational efficiency. To solve this problem, a fast Bayesian compressed sensing algorithm via relevance vector machine (FBCS–RVM) is proposed in this paper. The proposed method calculates the maximum marginal likelihood function under the framework of the RVM to obtain the optimal hyper-parameters; the scattering units corresponding to the non-zero optimal hyper-parameters are extracted as the target-areas in the imaging scene. Then, based on the target-areas, we simplify the measurement matrix and conduct sparse imaging. In addition, under low signal to noise ratio (SNR), low sampling rate, or high sparsity, the target-areas cannot always be extracted accurately, which probably contain several elements whose scattering coefficients are too small and closer to 0 compared to other elements. Those elements probably make the diagonal matrix singular and irreversible; the scattering coefficients cannot be estimated correctly. To solve this problem, the inverse matrix of the singular matrix is replaced with the generalized inverse matrix obtained by the truncated singular value decomposition (TSVD) algorithm to estimate the scattering coefficients correctly. Based on the rank of the singular matrix, those elements with small scattering coefficients are extracted and eliminated to obtain more accurate target-areas. Both simulation and experimental results show that the proposed method can improve the computational efficiency and imaging quality of LASAR 3D imaging compared with the state-of-the-art CS-based methods.

It is difficult for multichannel maneuvering synthetic aperture radar (SAR) to achieve ground moving target 2D velocity estimation and refocusing. In this paper, a novel method based on back projection (BP) and velocity SAR (VSAR) is proposed to cope with the issues. First, the static scene is reconstructed by BP to solve the imaging problem of multichannel maneuvering SAR. Then, the static clutter is suppressed, and the range velocity is estimated via VSAR processing. As for azimuth velocity estimation and refocusing, a velocity search method based on velocity-aided BP (VA-BP) and VSAR is proposed to accomplish them. First, each azimuth velocity in the search and the estimated range velocity are used to image the moving target in a small-sized subimage space by VA-BP, i.e., matching the range history and the Doppler phase of the moving target in the image processing. Then, multiple sets of multichannel SAR subimages corresponding to different azimuth velocities are generated, and the clutter of each set of multichannel SAR subimages is also suppressed by VSAR processing. After that, the azimuth velocity is estimated by searching the clutter-suppressed subimage of the first spatial receiving channel in each set of multichannel SAR subimages with the best refocusing quality measured by the minimum entropy. Simulation results show the proposed method can reach high accuracy in moving target 2D velocity estimation and refocusing with the absolute error of 2D velocity estimation smaller than 0.1 m/s.

Background: Conventional magnifying endoscopy with narrow-band imaging (NBI) observation of the gastric body mucosa shows dominant patterns in relation to the regular arrangement of collecting venules, subepithelial capillary network, and gastric pits., Aim: To evaluate the effectiveness of a new one-dual (near) focus, NBI mode in the assessment of the microscopic features of gastric body mucosa compared to conventional magnification., Methods: During 2021 and 2022, 68 patients underwent proximal gastrointestinal endoscopy using magnification endoscopic modalities subsequently applying acetic acid (AA). The GIF-190HQ series NBI system with dual focus capability was used for the investigation of gastric mucosa. At the time of the endoscopy, the gastric body mucosa of all enrolled patients was photographed using the white light endoscopy (WLE), near focus (NF), NF-NBI, AA-NF, and AA-NF-NBI modes., Results: The WLE, NF and NF-NBI endoscopic modes for all patients (204 images) were classified in the same order into three groups. Two images from each patient for the AA-NF and AA-NF-NBI endoscopic modes were classified in the same order. According to all three observers who completed the work independently, NF magnification was significantly superior to WLE ( P < 0.01), and the NF-NBI mode was significantly superior to NF magnification ( P < 0.01). After applying AA, the three observers confirmed that AA-NF-NBI was significantly superior to AA-NF ( P < 0.01). Interobserver kappa values for WLE were 0.609, 0.704, and 0.598, respectively and were 0.600, 0.721, and 0.637, respectively, for NF magnification. For the NF-NBI mode, the values were 0.378, 0.471, and 0.553, respectively. For AA-NF, they were 0.453, 0.603, and 0.480, respectively, and for AA-NF-NBI, they were 0.643, 0.506, and 0.354, respectively., Conclusion: When investigating gastric mucosa in microscopic detail, NF-NBI was the most powerful endoscopic mode for assessing regular arrangement of collecting venules, subepithelial capillary network, and gastric pits among the five endoscopic modalities investigated in this study. AA-NF-NBI was the most powerful endoscopic mode for analyzing crypt opening and intervening part., Competing Interests: Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background: Patients with chronic liver disease (CLD) might have an aggravated course after acquisition of coronavirus disease 2019 (COVID-19)., Aims: To analyse the outcomes of patients with CLD who were hospitalised due to COVID-19., Methods: The medical records of 4014 patients hospitalised because of COVID-19 in a regional referral hospital over a 12-month period were analysed. Patients with CLD were identified based on discharge diagnoses according to the International Classification of Diseases-10th Revision. Patients were followed for 30 days from admission and their outcomes (intensive care unit (ICU) admission, mechanical ventilation (MV) or death) were analysed., Results: Of the 4014 patients, 110 (2.7%) had CLD and 49 (1.2%) had cirrhosis. The median age of CLD patients was 67.5 years, 79 (71.8%) were males, 224 (23.5%) were obese, 56 (50.9%) reported alcohol abuse, 24 (21.8%) had non-alcoholic fatty liver disease, 11 (10%) had viral hepatitis and 98 (89.1%) had pneumonia. The median length of hospitalisation was 12 days; 32 (29.1%) patients required ICU admission and 23 (20.9%) patients required MV, while 43 (39.1%) died. In univariate analysis, patients with cirrhosis (45% vs 73%, hazard ratio (HR) = 2.95; P < 0.001), but not those with non-cirrhotic CLD (74% vs 73%; P > 0.05), experienced worse 30-day survival when compared with age, sex and COVID-19 duration-matched cohorts. In a logistic regression analysis conducted on the overall and matched cohorts, liver cirrhosis, but not CLD, predicted inferior survival independently of age, comorbidities and severity of COVID-19, with a fourfold higher adjusted risk of 30-day mortality., Conclusion: Cirrhosis is independently associated with higher 30-day mortality of hospitalised patients with COVID-19., (© 2022 Royal Australasian College of Physicians.)

Background and Aims: We aimed to validate newly proposed noninvasive criteria for diagnosing clinically significant portal hypertension (CSPH) using liver stiffness measurements (LSM) by transient elastography (TE) and platelet count., Methods: Diagnostic performance of these new criteria for CSPH (LSM ≥ 25 kPa to rule in and Plt ≥ 150 × 10 9 /L + LSM ≤ 15 kPa to rule out CSPH) were retrospectively tested in an independent cohort of consecutive patients who underwent hepatic venous pressure gradient (HVPG) measurements and liver biopsy due to suspicion of compensated advanced chronic liver disease. Suspicion of cACLD was based on LSM ≥ 10 kPa by TE or results of liver imaging, without overt signs of CSPH. Patients with conditions known to affect results of LSM (ALT > 5 × ULN, liver congestion, extrahepatic biliary obstruction, infiltrative liver neoplasms) were excluded., Results: Seventy six (76) patients were included: 78.9% males, mean age 62 years, 36.8% suffered from alcoholic, 30.3% nonalcoholic fatty liver disease, 14.5% chronic viral hepatitis, 30.3% were obese, 52.6% had HVPG ≥ 10 mmHg, 56.6% had platelet count ≥ 150 × 10 9 /L. LSM ≥ 25 kPa had 88.9% specificity (95% CI 73.9-96.9) to rule in, whereas Plt ≥ 150 + LSM ≤ 15 kPa had 100% sensitivity (95% CI 91.1-100) to rule out CSPH., Conclusion: By using these simple noninvasive criteria 49/76 (64.5%) patients could be classified correctly for the presence/absence of CSPH, thus obviating the need for HVPG measurements., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Introduction: Oesophageal varices are routinely diagnosed by esophagogastroduodenoscopy (EGD), and their bleeding has high mortality. We aimed to evaluate diagnostic performance of biochemical tests in comparison to elastography-based approaches, as non-invasive alternatives to EGD, for ruling-out high risk oesophageal varices (HRV)., Material and Methods: Retrospective analysis of patients (N = 861) who underwent liver stiffness measurement (LSM) by transient elastography (TE) in a single centre over 5-year period, with available results of EGD (within 3 months from LSM). Only patients with suspicion of compensated advanced chronic liver disease (cACLD) defined by LSM ≥ 10 kPa were included comprising the final cohort of 73 subjects. Original and expanded Baveno VI criteria (B6C), controlled attenuation parameter (CAP), platelet count (PLT), aspartate aminotransferase to PLT ratio index (APRI), Fibrosis-4 index (FIB4), model for end stage liver disease (MELD) score were evaluated against the results of EGD that served as the reference method., Results: Analysed patients had median age 62 years, 59/73 (0.81) were males, 54/73 (0.74) had alcoholic/non-alcoholic fatty liver disease, and 21/73 (0.29) had HRV. In multivariate logistic regression analysis only LSM and PLT were independently associated with HRV. The best performing tests for ruling-out HRV (% of spared EGD; % of missed HRV) were respectively: LSM < 20 kPa (53.4%; 0%), B6C (38%; 0%), Expanded B6C (47.9%; 4.8%); PLT > 214x10 9 /L (21.9%; 0%); FIB4 ≤ 1.8 (21.4%; 0%), APRI ≤ 0.34 (12.3%; 0%). CAP, MELD = 6 alone or combined with PLT > 150(x10 9 /L) did not show acceptable performance., Conclusion: The best performing biochemical tests for ruling-out HRV in our cohort of patients were PLT and FIB-4, but they were still outperformed by elastography-based approaches., Competing Interests: Potential conflict of interest None declared., (Croatian Society of Medical Biochemistry and Laboratory Medicine.)

Background: Liver involvement in Coronavirus disease 2019 (COVID-19) has been recognised. We aimed to investigate the correlation of non-invasive surrogates of liver steatosis, fibrosis and inflammation using transient elastography (TE) and FibroScan-AST (FAST) score with (a) clinical severity and (b) 30-day composite outcome of mechanical ventilation (MV) or death among patients hospitalized due to COVID-19., Method: Patients with non-critical COVID-19 at admission were included. Liver stiffness measurement (LSM) and controlled attenuation parameter (CAP) were assessed by TE. Clinical severity of COVID-19 was assessed by 4C Mortality Score (4CMS) and need for high-flow nasal cannula (HFNC) oxygen supplementation., Results: 217 patients were included (66.5% males, median age 65 years, 4.6% with history of chronic liver disease). Twenty-four (11.1%) patients met the 30-day composite outcome. Median LSM, CAP and FAST score were 5.2 kPa, 274 dB/m and 0.31, respectively, and neither was associated with clinical severity of COVID-19 at admission. In multivariate analysis FAST > 0.36 (OR 3.19, p = 0.036), 4CMS (OR 1.68, p = 0.002) and HFNC (OR 7.03, p = 0.001) were independent predictors of adverse composite outcome., Conclusion: Whereas LSM and CAP failed to show correlation with COVID-19 severity and outcomes, FAST score was an independent risk factor for 30-day mortality or need for MV.

We aimed to investigate the diagnostic performance of new 2-D shear-wave elastography (SWE) with propagation maps and attenuation imaging (ATI) for quantification of fibrosis and steatosis in non-alcoholic fatty liver disease (NAFLD). Consecutive patients with NAFLD and healthy volunteers underwent liver stiffness measurement and steatosis quantification by means of vibration-controlled transient elastography coupled with the controlled attenuation parameter as the reference and by 2-D shear-wave elastography (2-D-SWE) with propagation maps and ATI as the investigational methods. We included 232 participants (164 in the NAFLD group and 68 in the healthy control group): 51.7%/49.3% women/men; mean age, 54.2 ± 15.2 y; mean body mass index, 29.4 ± 6.5 kg/m 2 . Significant correlations were found between 2-D-SWE and vibration-controlled transient elastography (r = 0.71, p < 0.0001) and between ATI and the controlled attenuation parameter (r = 0.72, p < 0.0001). NAFLD-specific 2-D-SWE liver stiffness measurement cutoffs were as follows-F ≥ 2: 7.9 kPa (area under the curve [AUC] = 0.91); F ≥ 3: 10 kPa (AUC = 0.92); and F = 4: 11.4 kPa (AUC = 0.95). For steatosis, the best cutoffs by ATI were as follows-S1 = 0.73 dB/cm/MHz (AUC = 0.86); S2 = 0.76 dB/cm/MHz (AUC = 0.86); and S3 = 0.80 dB/cm/MHz (AUC = 0.83). According to Baveno VI criteria, the optimal 2-D-SWE liver stiffness measurement for diagnosing liver cirrhosis is 15.5 kPa (AUC = 0.94), and for ruling out compensated advanced chronic liver disease it is 9.2 kPa (AUC = 0.92). To conclude, 2-D-SWE with propagation maps and ATI is reliable for quantification of liver fibrosis and steatosis in patients with NAFLD., (Copyright © 2021 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)

Aims: To investigate morbidity and mortality in a real-life cohort of patients with type 2 diabetes (T2D) in relation to prevalence and severity of nonalcoholic fatty liver disease (NAFLD)., Methods: Patients with T2D were referred for assessment of liver fibrosis by the FIB-4 test and liver stiffness measurement (LSM) by vibration-controlled transient elastography (VCTE). Liver steatosis was quantified by the controlled attenuation parameter (CAP). These patients were followed until death or censored date., Results: Among 454 patients (52% males, mean age 62.5 years, BMI 30.9 kg/m 2 ), 82.6% was overweight, 77.8% had fatty liver, and 9.9% and 3.1% had LSM and FIB-4 values suggestive of advanced fibrosis, respectively. During the follow-up period of median 2 years, 106 (23%) patients experienced adverse event (11% cardiovascular) and 17 (3.7%) died, whereas no liver-related morbidity or mortality was observed. Independent predictors of adverse outcomes were age and higher platelet count, while FIB-4, LSM, and CAP were not., Conclusion: In a cohort of T2D patients, no liver-related morbidity or mortality occurred during 2 years. Our patients probably have low real prevalence of advanced fibrosis which is likely overestimated by LSM ≥ 9.6 kPa. Liver fibrosis may be safely reassessed in the 2 years interval in noncirrhotic patients with T2D., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2021 Ivica Grgurevic et al.)

Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Competing Interests: The authors declare that they have no conflict of interest.

Background and study aims  A universal European training program in gastroenterology and hepatology is currently not available. The European Board of Gastroenterology and Hepatology (EBGH) has produced guidance regarding expected competencies for European gastroenterology trainees but it is unclear whether these have been incorporated in national curricula. The aim of this study was to provide an in-depth assessment of training and research opportunities, professional activities and of socioeconomic aspects of gastroenterology training across Europe through a web-based 90-point questionnaire. Materials and methods  Physicians in their last year or who had recently finished their training, from 16 European countries, were invited to answer the questionnaire. Results  A total of 144 physicians answered the survey. A minimum number of procedures is required before completing training in nine of 16 countries (56 %). Overall, European trainees dedicate a median of 12 months (IQR 6-25) of their training period to endoscopy and a median of 3 months (IQR 0-6) to ultrasound. Training in interventional endoscopy was not always exhaustive, as about 50 % of participants performed fewer of several interventional procedures than was recommended by EBGH, most participants did not perform endoscopic hemostasis or endoscopic mucosal resection, and nearly a half of participants had no access to pancreatobiliary endoscopy training. Finally, up to 13 % of residents complete their training without the supervision of a mentor. Conclusion  In this large European survey, deep gaps and considerable differences in several gastroenterology training activities were found both among and within 16 European countries. Homogenization of educational programs and training opportunities across Europe is therefore necessary., Competing Interests: Competing interests The authors declare that they have no conflict of interest.

Objectives: To investigate diagnostic performance of point shear wave elastography by elastography point quantification (ElastPQ) for non-invasive assessment of liver fibrosis in patients with chronic liver diseases (CLD)., Methods: Liver stiffness measurement (LSM) by transient elastography (TE) and ElastPQ was performed in patients with CLD and healthy volunteers. The stage of liver fibrosis was defined by TE which served as the reference. We compared two methods by using correlation, area under the receiver operating characteristics curve (AUC) analysis, Bland and Altman plot and Passing-Bablok regression., Results: A total of 185 subjects (20 healthy volunteers and 165 patients with CLD (128 non-alcoholic fatty liver disease), 83 (44.9%) females, median age 53 years, BMI 27.3 kg/m 2 ) were evaluated. There were 24.3%, 13.5% and 11.4% patients in ≥ F2, ≥ F3 and F4 stage, respectively. The best performing cutoff LSM values by ElastPQ were 5.5 kPa for F ≥ 2 (AUC = 0.96), 8.1 kPa for F ≥ 3 (AUC = 0.98) and 9.9 kPa for F4 (AUC = 0.98). Mean (SD) difference between TE and ElastPQ measurements was 0.98 (3.27) kPa (95% CI 0.51-1.45, range 4.99-21.60 kPa). Two methods correlated significantly (r = 0.86; p < 0.001), yet Bland and Altman plot demonstrated difference between measurements, especially with TE values > 10 kPa. Passing and Bablok regression analysis yielded significant constant and proportional difference between ElastPQ and TE., Conclusion: ElastPQ is reliable method for assessment of liver fibrosis but LSM values are not interchangeable with TE, especially above 10 kPa. Diagnostic performance of ElastPQ for sub-classification of patients with compensated advanced chronic liver disease should therefore be furtherly investigated., Key Points: • ElastPQ appears to be reliable method for assessment of liver fibrosis, with data presented here mostly applicable to NAFLD. • LSM values produced by TE and ElastPQ are NOT interchangeable-in values < 10 kPa, they are similar, but in values > 10 kPa, they appear to be increasingly and significantly different. • Diagnostic performance of ElastPQ for sub-classification of patients with compensated advanced chronic liver disease should be furtherly investigated.

The aim of the study was to explore (a) prevalence and grade of nonalcoholic fatty liver (NAFL) among outpatients referred for abdominal ultrasound (US) examination and (b) relationship between the presence and severity of liver steatosis and metabolic syndrome (MS). This was a retrospective analysis of patients without history of liver disease examined by abdominal US in the University hospital setting. US was used to detect and semiquantitatively grade (0-3) liver steatosis. Data on patients' age, gender, body mass index (BMI), impaired glucose metabolism (IGM), atherogenic dyslipidaemia (AD), raised blood pressure (RBP), transaminases, and platelet counts were obtained from medical records. MS was defined as having at least 3 of the following components: obesity, IGM, AD, and RBP. Of the 631 patients (median age 60 years, median BMI 27.4 kg/m2, and 57.4% females) 71.5% were overweight and 48.5% had NAFL. In the subgroup of 159 patients with available data on the components of MS, patients with higher US grade of steatosis had significantly higher BMI and increased prevalence of obesity, IGM, AD, RBP, and accordingly more frequently had MS, whereas they did not differ in terms of age and gender. NAFL was independently associated with the risk of having MS in a multivariate model adjusted for age, gender, BMI, and IGM. The grade of liver steatosis did not correlate with the presence of liver fibrosis. We demonstrated worrisome prevalence of obesity and NAFL in the outpatient population from our geographic region. NAFL is independently associated with the risk of having MS implying worse prognosis.

The aim of the study was to explore predictive value of the ALBI, PALBI and MELD scores on survival in patients resected for hepatocellular carcinoma with compensated liver cirrhosis and no macrovascular infiltration. In this retrospective study, longitudinal survival analysis was performed. We analyzed patient/tumor characteristics and MELD, ALBI and PALBI scores as liver function tests for predicting survival outcome. Survival was analyzed from the date of liver resection until death, liver transplantation, or end of follow-up. Patients were stratified for age, cirrhosis etiology, presence of esophageal varices, hepatocellular carcinoma stage, microvascular invasion, histologic differentiation, and resection margins. We identified 38 patients (alcoholic cirrhosis in 84.2% of patients) resected over an 8-year period. Median preoperative MELD score was 8, ALBI score -2.63, and PALBI score -2.38. During the follow-up period, 24 patients died. Estimated median survival time was 36 months. Microvascular invasion was observed in 33 patients. Higher ALBI score was associated with 23.1% higher relative risk of death. PALBI score was associated with 12.1% higher relative risk of death, whereas MELD score was not associated with the risk of death. In conclusion, ALBI score demonstrated significant predictive capabilities for survival in patients with compensated cirrhosis resected for hepatocellular carcinoma.

Background & Aims: To analyse elastographic characteristics of focal liver lesions (FLL)s and diagnostic performance of real-time two-dimensional shear-wave elastography (RT-2D-SWE) in order to differentiate benign and malignant FLLs., Methods: Consecutive patients diagnosed with FLL by abdominal ultrasound (US) underwent RT-2D-SWE of FLL and non-infiltrated liver by intercostal approach over the right liver lobe. The nature of FLL was determined by diagnostic work-up, including at least one contrast-enhanced imaging modality (MDCT/MRI), check-up of target organs when metastatic disease was suspected and FLL biopsy in inconclusive cases., Results: We analysed 196 patients (median age 60 [range 50-68], 50.5% males) with 259 FLLs (57 hepatocellular carcinomas, 17 cholangiocarcinomas, 94 metastases, 71 haemangiomas, 20 focal nodular hyperplasia) of which 70 (27%) were in cirrhotic liver. Malignant lesions were stiffer (P < .001) with higher variability in intralesional stiffness (P = .001). The best performing cut-off of lesion stiffness was 22.3 kPa (sensitivity 83%; specificity 86%; positive predictive value [PPV] 91.5%; negative predictive value [NPV] 73%) for malignancy. Lesion stiffness <14 kPa had NPV of 96%, while values >32.5 kPa had PPV of 96% for malignancy. Lesion stiffness, lesion/liver stiffness ratio and lesion stiffness variability significantly predicted malignancy in stepwise logistic regression (P < .05), and were used to construct a new Liver Elastography Malignancy Prediction (LEMP) score with accuracy of 96.1% in validation cohort (online calculator available at http://bit.do/lemps)., Conclusion: The comprehensive approach demonstrated in this study enables correct differentiation of benign and malignant FLL in 96% of patients by using RT-2D-SWE., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Liver stiffness measurement (LSM) by ultrasound-based elastography may be used to non-invasively discriminate between the stages of liver fibrosis, rule out cirrhosis and follow its evolution, including the prediction of the presence of oesophageal varices. The same is possible in order to diagnose clinically significant portal hypertension, referring primarilyto transient elastography and LSM values ≥20-25 kPa. The same approach may be used to reliably rule out the presence ofoesophageal varices (LSM <20 kPa + platelets >150x109/L). These recommendations refer primarily to patients with viral aetiology of chronic liver disease (hepatitis C), while additional studies are required for other aetiologies. While spleen stiffness measurement (SSM) also poses a logical choice in this indication, controversial results have nevertheless been published on this issue. It should be emphasized, however, that more recent data indicate that this parameter should be included in the diagnostic algorithm for portal hypertension, if not as the sole then as a part of a sequential algorithm, combined with LSM. Until now, transient elastography has been most extensively studied and founded on scientific evidence, although the results of other ultrasound-based elastography techniques demonstrate the same trend for the non-invasive assessment of portal hypertension.

Purpose: To investigate (1) diagnostic performance of transabdominal color doppler ultrasound (US) and endoscopic ultrasound (EUS) for detection and sub-classification of common bile duct varices (CBDV) in patients with portal vein thrombosis (PVT), and (2) clinical significance and natural history of CBDV subtypes., Patients and Methods: During a 4-year period, 56 patients with PVT underwent US and EUS for the presence and subtypes of CBDV. Natural history was analyzed for patients who attended control visits., Results: CBDV were diagnosed in 57 and 59 % of patients with US and EUS, respectively. In 19 % of patients, EUS revealed different CBDV subtypes than previously seen by US. The most common were paracholedochal (PCV), while the least common were epicholedochal (ECV) and Submucosal varices (SMV). Nine patients had obstructive jaundice and underwent ERCP which was complicated by hemobilia in two patients with SMV. Among eight patients who underwent control EUS (median follow-up 60 months), the form of CBDV remained unchanged. Two patients bled from esophageal varices, both with ECV., Conclusion: While abdominal US and EUS are equally sensitive for detection of CBDV, EUS allows more precise determination of CBDV subtype. Patients with SMV might be at increased risk of bleeding upon ERCP.

Objectives: To investigate the performance of real-time 2D shear wave elastography (RT 2D-SWE) for non-invasive staging of liver disease in patients with chronic viral hepatitis (CVH)., Materials and Methods: Naive CVH patients underwent liver (LS) and spleen stiffness (SS) measurements by an intercostal approach. Patients with ALT >3× upper limit of normal, cholestasis as revealed by dilated intrahepatic biliary tree, and liver congestion were excluded. Results were expressed in kPa and compared to histological stage (Ishak) of liver fibrosis (LF). Patients with decompensated liver cirrhosis (LC) were diagnosed using standard clinical, ultrasound, and endoscopic criteria., Results: Of 123 patients, LS was successfully measured in 79.7% and SS in 53.7%. LS accurately differentiated between liver disease stages, with cut-off values of 8.1 (AUC 0.991) for F ≥ 3, 10.8 kPa (AUC 0.954) for F ≥ 5, and 27 kPa (AUC 0.961) for decompensated LC. SS was significantly different between non-cirrhotic stages (F0-4) and LC (cut-off 24 kPa; AUC 0.821). While both LS and SS increased with liver disease progression, the difference between them decreased, as reflected by the stiffness ratio index., Conclusions: RT 2D-SWE can accurately differentiate between the stages of LF, and can distinguish LF from LC and compensated from decompensated LC., Key Points: • RT 2D-SWE is an accurate method for assessment of liver fibrosis. • RT 2D-SWE is applicable in 80% of patients with chronic viral hepatitis. • RT 2D-SWE accurately differentiates compensated from decompensated liver cirrhosis. • Both liver and spleen stiffness increase with progression of liver fibrosis. • In cirrhosis, the difference between liver and spleen stiffness decreases.

Aim: Primary: to evaluate predictivity of liver stiffness (LS), spleen stiffness (SS), and their ratio assessed by real-time 2D shear wave elastography (RT-2D-SWE) for adverse outcomes (hepatic decompensation, hepatocellular carcinoma or death; "event") in compensated liver cirrhosis (LC) patients. Secondary: to evaluate ability of these measures to discriminate between cirrhotic patients with/without esophageal varices (EV)., Methods: Predictivity of LS, SS, and LS/SS was assessed in a retrospectively analyzed cohort of compensated LC patients (follow-up cohort) and through comparison with incident patients with decompensated cirrhosis (DC) (cross-sectional cohort). Both cohorts were used to evaluate diagnostic properties regarding EV., Results: In the follow-up cohort (n=44) 18 patients (40.9%) experienced an "event" over a median period of 28 months. LS≥21.5 kPa at baseline was independently associated with 3.4-fold (95% confidence interval [CI] 1.16-10.4, P=0.026) higher risk of event. Association between SS and outcomes was weaker (P=0.056), while there was no association between LS/SS ratio and outcomes. Patients with DC (n=43) had higher LS (35.3 vs 18.3 kPa, adjusted difference 65%, 95% CI 43%-90%; P<0.001) than compensated patients at baseline. Adjusted odds of EV increased by 13% (95% CI 7.0%-20.0%; Plt;0.001) with 1 kPa increase in LS. At cut-offs of 19.7 and 30.3 kPa, LS and SS had 90% and 86.6% negative predictive value, respectively, to exclude EV in compensated patients., Conclusion: This is the first evaluation of RT-2D-SWE as a prognostic tool in LC. Although preliminary and gathered in a limited sample, our data emphasize the potential of LS to be a reliable predictor of clinical outcomes and the presence of EV in LC patients.

Endoscopic ultrasound (EUS) is continuously stepping into the therapeutic arena, simultaneously evolving in different directions, such as the management of pancreatic and biliary diseases, celiac neurolysis, delivering local intratumoral therapy, and EUS-guided endosurgery. EUS-guided vascular procedures are also challenging, considering the variety of vascular pathology, proximity of the vascular structures to the GI tract wall, high resolution, and real-time guidance offering an attractive access route and precise delivery of the intervention. The literature on vascular therapeutic EUS demonstrates techniques for the management of upper GI variceal and nonvariceal bleeding, pseudoaneurysms, and coiling and embolization procedures, as well as the creation of intrahepatic portosystemic shunts. The paucity of studies, diversity of study designs, and the number of animal model studies hamper a systematic approach to the conclusion and decision making important to clinicians and healthcare policy makers. Nevertheless, theoretical benefits and findings up to date concerning technical feasibility, efficacy, and safety of the procedures drive further research and development in this rather young therapeutic arena.

Background: There is considerable international interest in exploiting the potential of digital solutions to enhance the quality and safety of health care. Implementations of transformative eHealth technologies are underway globally, often at very considerable cost. In order to assess the impact of eHealth solutions on the quality and safety of health care, and to inform policy decisions on eHealth deployments, we undertook a systematic review of systematic reviews assessing the effectiveness and consequences of various eHealth technologies on the quality and safety of care., Methods and Findings: We developed novel search strategies, conceptual maps of health care quality, safety, and eHealth interventions, and then systematically identified, scrutinised, and synthesised the systematic review literature. Major biomedical databases were searched to identify systematic reviews published between 1997 and 2010. Related theoretical, methodological, and technical material was also reviewed. We identified 53 systematic reviews that focused on assessing the impact of eHealth interventions on the quality and/or safety of health care and 55 supplementary systematic reviews providing relevant supportive information. This systematic review literature was found to be generally of substandard quality with regards to methodology, reporting, and utility. We thematically categorised eHealth technologies into three main areas: (1) storing, managing, and transmission of data; (2) clinical decision support; and (3) facilitating care from a distance. We found that despite support from policymakers, there was relatively little empirical evidence to substantiate many of the claims made in relation to these technologies. Whether the success of those relatively few solutions identified to improve quality and safety would continue if these were deployed beyond the contexts in which they were originally developed, has yet to be established. Importantly, best practice guidelines in effective development and deployment strategies are lacking., Conclusions: There is a large gap between the postulated and empirically demonstrated benefits of eHealth technologies. In addition, there is a lack of robust research on the risks of implementing these technologies and their cost-effectiveness has yet to be demonstrated, despite being frequently promoted by policymakers and "techno-enthusiasts" as if this was a given. In the light of the paucity of evidence in relation to improvements in patient outcomes, as well as the lack of evidence on their cost-effectiveness, it is vital that future eHealth technologies are evaluated against a comprehensive set of measures, ideally throughout all stages of the technology's life cycle. Such evaluation should be characterised by careful attention to socio-technical factors to maximise the likelihood of successful implementation and adoption.

Introduction: The use of video capsule endoscopy (VCE) started in late 2001 when it was approved by the Food and Drug Administration (FDA). Since then, we are able to visualize small bowel mucosa with a minimally invasive technique, very comfortable for patients, with very few complications and without the need of hospitalization. At Dubrava University Hospital, we have been using VCE since October 2006, and by February 2008 we examined 30 patients., Aim: The aim of the study was to present our preliminary results in the use of VCE during a period of one year and five months. We also report indications and contraindications for VCE, and patient preparation., Methods: In this retrospective study we reviewed records on 30 patients that had undergone VCE at Dubrava University Hospital, Zagreb, Croatia, between October 2006 and February 2008. The indications for VCE were restricted to the investigation of obscure gastrointestinal bleeding (OGIB) (n = 10), iron deficiency anemia (n = 2), suspected Crohn's disease (n = 1), assessment of known small bowel Crohn's disease (n = 5), unexplained diarrhea (n = 6), chronic abdominal pain (n = 3), suspected ganglioneurinoma (n = 1) and suspected polyposis syndrome (n = 2). To be eligible for VCE, patients had to have previously undergone usual diagnostic methods of upper endoscopy, colonoscopy and small bowel follow-through, without discovering the cause of their symptoms. Before swallowing the capsule, patients were instructed not to eat anything the day before VCE and to drink 4 L of liquids, and additional 2 L magnesium sulfate. In all patients we used Olympus EndoCapsule Software (Tokyo, Japan). Results were interpreted by one specialist, gastroenterologist., Results: Definitive diagnosis was made in 15 patients. Suspect findings were noted in 2 patients, whereas no diagnosis could be established in 13 patients. According to our experience, VCE is a promising new method that has a high diagnostic yield in patients with OGIB and known Crohn's disease. Use of VCE enabled definitive diagnosis to be made in 6 of 10 patients with OGIB after all previously used diagnostic methods had failed to reveal any pathological finding. In the group of OGIB patients, angiodysplasia was the most common findings (4 of 10 patients). In the group of patients with Crohn's disease, progression of the disease to neotherminal ileum was recorded in 3 of 5 patients. Our experience also confirmed the VCE to be a very safe method; capsule retention was recorded in only one patient., Discussion: Although VCE enabled us to visualize the small bowel mucosa and therefore helped us establish the diagnosis in cases where other diagnostic methods had failed, it still has some important limitations, the major one being the impossibility to take biopsies and to perform any therapeutic procedures. However, it has a high diagnostic yield in cases of OGIB and Crohn's disease, is very comfortable for patients, and has a low incidence of complications (capsule retention). When making definitive diagnosis, one should always consider patient's history and physical examination findings as well as other possible causes of small bowel mucosal impairment., Conclusion: VCE is a promising new technique that has a high diagnostic yield in patients with OGIB and Crohn's disease. However, more studies need to be done to establish definitive indications, cost-effectiveness and the best way of patient preparation for VCE.