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1.
J Clin Med ; 13(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38999388

RESUMO

Objective: This study aimed to assess the relative and absolute intra- and inter-rater reliability of supraspinatus tendon (SST) thickness. Materials: Thirty adolescent swimmers with supraspinatus (SS) tendinopathy (n = 15) and a control-matched group (n = 15) were evaluated. Tendon thickness was measured according to four different measure procedures, i.e., (1) at 15 mm, (2) at 10, 20, and 30 mm, (3) at 10, 15, and 20 mm, and (4) 5 and 10 mm lateral to the most hyperechogenic reference point of the biceps tendon. Each examiner took two US images for the test measurements with a 10 min rest period. After 30 min, the subjects underwent retest measurements that were also repeated 1 week later. Results: SST thickness was greater in swimmers with SS tendinopathy compared with the matched control group for each procedure and rater (p < 0.001). Intra- and inter-rater reliability was good to excellent (ICC2.3: 0.78-0.98 and 0.83-0.97, respectively) in both groups. The lowest intra- and inter-rater reliability was found in procedures no. 2 and 4 (ICC2.3: 0.78 and 0.83). However, procedure no. 3 was the most reliable with the lowest error rate (ICC2.3: 0.92-0.97; SEM: 0.05-0.10 mm; MDC: 0.14-0.28 mm). Conclusions: The study confirmed the diagnostic value of ultrasound in SS tendinopathy. A multiple-reference-point procedure including a simple methodology (10, 15, and 20 mm from biceps tendon), was defined as the most reliable, expressed by the highest intra- and inter-rater ICCs.

2.
Vet Res Commun ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967743

RESUMO

The donkey has always been a notable working animal and its importance as a companion animal has been growing over the last few years. However, there are only a few studies about cardiology in this species. Therefore, this study aimed to evaluate the influence of age, sex, training, and bodyweight on cardiac dimension in mixed-breed donkeys. Forty-five clinically and para-clinically healthy mixed-breed donkeys were included, and B-mode and M-mode echocardiographic measurements were recorded. Multivariate linear regression analysis was performed to identify the effect of age, sex, bodyweight, and training on cardiac measurements. Most of the echocardiographic measurements showed a strong statistically significant correlation with bodyweight. Linear regression analysis between echocardiographic measurements and bodyweight was performed to obtain the values of the intercept and slope of the linear equation to calculate the echocardiographic measurements as a function of bodyweight. This is the first study reporting a strong linear correlation between echocardiographic measurements and bodyweight and reporting a correlation between training and echocardiographic parameters in donkeys, suggesting that this variable should be considered when assessing cardiac dimensions in these animals.

3.
Sci Rep ; 14(1): 13253, 2024 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858500

RESUMO

We aimed to implement four data partitioning strategies evaluated with four federated learning (FL) algorithms and investigate the impact of data distribution on FL model performance in detecting steatosis using B-mode US images. A private dataset (153 patients; 1530 images) and a public dataset (55 patient; 550 images) were included in this retrospective study. The datasets contained patients with metabolic dysfunction-associated fatty liver disease (MAFLD) with biopsy-proven steatosis grades and control individuals without steatosis. We employed four data partitioning strategies to simulate FL scenarios and we assessed four FL algorithms. We investigated the impact of class imbalance and the mismatch between the global and local data distributions on the learning outcome. Classification performance was assessed with area under the receiver operating characteristic curve (AUC) on a separate test set. AUCs were 0.93 (95% CI 0.92, 0.94) for source-based partitioning scenario with FedAvg, 0.90 (95% CI 0.89, 0.91) for a centralized model, and 0.83 (95% CI 0.81, 0.85) for a model trained in a single-center scenario. When data was perfectly balanced on the global level and each site had an identical data distribution, the model yielded an AUC of 0.90 (95% CI 0.88, 0.92). When each site contained data exclusively from one single class, irrespective of the global data distribution, the AUC fell in the range of 0.34-0.70. FL applied to B-mode US images provide performance comparable to a centralized model and higher than single-center scenario. Global data imbalance and local data heterogeneity influenced the learning outcome.


Assuntos
Algoritmos , Fígado Gorduroso , Ultrassonografia , Humanos , Ultrassonografia/métodos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Fígado Gorduroso/diagnóstico por imagem , Fígado Gorduroso/patologia , Adulto , Curva ROC , Aprendizado de Máquina , Área Sob a Curva , Idoso
4.
Curr Med Imaging ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38918981

RESUMO

BACKGROUND: Patient safety is paramount in ultrasound procedures, particularly in obstetric ultrasounds involving both the mother and fetus. The thermal and mechanical indices (TI and MI) serve as crucial indicators of the acoustic output during ultrasound. Clinicians and specialists must know these indices and ensure they are within safe ranges. This study aimed to assess the parameters of acoustic output power employed in obstetric ultrasound (thermal and mechanical index). METHODOLOGY: A cross-sectional observational study conducted at Maternity and Children's Hospital in Al-Madina Al-Munawwarah, the data was collected from obstetric scanning of 411 pregnant females using a data collection sheet including gravida and women's age, gestational age, scan mode, scan time, and thermal and mechanical index (TI and MI) values. RESULTS: The study found that there were significant differences in safety indices measurement between different modes; in Pulsed Doppler, mean Thermal Index Bone (TIb) had the highest value (1.60±0.40), and the Mechanical Index (MI) was the lowest (0.68±0.33). There were insignificant differences in safety indices values in different modes in different trimesters. The thermal indices of soft tissue and bony structure (TIs and TIb) of brightness mode (B-mode) were constant in all trimesters, but the MI in the first trimester was lower than in the other trimesters. CONCLUSION: This study found significant differences in TIs, TIb, and MI in different modes of obstetric ultrasound. Pulsed Doppler ultrasonography had the highest TIb value and a lower MI value. The ultrasound acoustic exposure output parameters were within the standard's recommended limit.

5.
Cureus ; 16(5): e60308, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38883001

RESUMO

Background Compelling observational data suggest that heightened levels of fasting blood phosphate are linked to a higher likelihood of cardiovascular disease, spanning across both the general populace and individuals grappling with chronic kidney disease (CKD). This study aimed to explore the possible correlation between carotid intima-media thickness (CIMT) and blood phosphate levels among those afflicted with chronic renal dysfunction. Objective The primary goal of this study is to determine the potential association between blood phosphate levels and CIMT in patients with CKD. Methodology In the department of nephrology, prospective research was conducted among patients who had a history of CKD. A total of 30 patients were included, with 20 males and 10 females. Every case had a thorough physical examination and history. Every patient underwent a laboratory evaluation, which included measurements of the CIMT and renal function testing. At a distance of 1 cm from the carotid bulb, the CIMT was measured using B-mode ultrasonography. After compilation, the data were examined. Results The majority of the patients, according to this study, were male and over 50 years old. The Stage II patients in the study had a higher mean systolic blood pressure; however, the difference was not statistically significant. Patients with Stage V (D) disease exhibited higher diastolic blood pressure, but not statistically significant. An increase in the mean serum creatinine level that was statistically significant was linked to Stage V (D) renal disease. A higher mean blood urea was linked to Stage V (D) sickness; however, this relationship was not statistically significant. There was no statistical difference in the mean serum calcium levels between the different stages of renal disease. Higher mean blood phosphate levels were linked to Stage III renal disease, but not in a statistically meaningful way. Although it was higher in Stage IV kidney disease, the mean CIMT was not statistically significant between the stages of renal illness. Conclusions Although a positive correlation was shown, a direct relationship between serum phosphate levels was not established by this investigation. The severity of renal disease has been demonstrated to correlate with elevated serum phosphate levels.

6.
Reprod Domest Anim ; 59(6): e14621, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38828534

RESUMO

Estimating the parturition date in dogs is challenging due to their reproductive peculiarities that. Ultrasonographic examination serves as a tool for studying embryo/foetal biometry and estimating the time of parturition by measuring foetal and extra-foetal structures. However, due to reproductive differences among various dog breeds, such estimates may have a non-significant pattern, representing inaccuracies in the estimated date of birth. This study aimed to monitor pregnant Toy Poodle bitches and establish relationships between ultrasonographically measured foetal and extra-foetal dimensions and the remaining time until parturition. Eighteen pregnant Toy Poodle bitches were subjected to weekly ultrasonographic evaluations and measurements of the inner chorionic cavity diameter, craniocaudal length (CCL), biparietal diameter (BPD), diameter of the deep portion of diencephalo-telencephalic vesicle (DPTV), abdominal diameter, thorax diameter (TXD), placental thickness and the renal diameter (REND). These parameters were retrospectively correlated with the date of parturition and linear regressions were established between gestational measurements and days before parturition (DBP). All analyses were conducted using the Statistical Package for Social Sciences (IBM® SPSS®) program at a 5% significance level. The foetal measurements that showed a high correlation (r) and reliability (R2) with DBP were BPD [(DBP = [15.538 × BPD] - 39.756), r = .97 and R2 = .93], TXD [(DBP = [8.933 × TXD] - 32.487), r = .94 and R2 = .89], DPTV [(DBP = [34.580 × DPTV] - 39.403), r = .93 and R2 = .86] and REND [(DBP = [13.735 × REND] - 28.937), r = .91 and R2 = .82]. This statistically validates the application of these specific formulas to estimate the parturition date in Toy Poodle bitches.


Assuntos
Parto , Ultrassonografia Pré-Natal , Animais , Feminino , Gravidez , Cães/embriologia , Ultrassonografia Pré-Natal/veterinária , Biometria , Feto/anatomia & histologia , Feto/diagnóstico por imagem , Estudos Retrospectivos , Placenta/diagnóstico por imagem , Placenta/anatomia & histologia , Embrião de Mamíferos/fisiologia , Idade Gestacional
7.
Front Neurosci ; 18: 1339075, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38808029

RESUMO

Aim: Conventional approaches to diagnosing common eye diseases using B-mode ultrasonography are labor-intensive and time-consuming, must requiring expert intervention for accuracy. This study aims to address these challenges by proposing an intelligence-assisted analysis five-classification model for diagnosing common eye diseases using B-mode ultrasound images. Methods: This research utilizes 2064 B-mode ultrasound images of the eye to train a novel model integrating artificial intelligence technology. Results: The ConvNeXt-L model achieved outstanding performance with an accuracy rate of 84.3% and a Kappa value of 80.3%. Across five classifications (no obvious abnormality, vitreous opacity, posterior vitreous detachment, retinal detachment, and choroidal detachment), the model demonstrated sensitivity values of 93.2%, 67.6%, 86.1%, 89.4%, and 81.4%, respectively, and specificity values ranging from 94.6% to 98.1%. F1 scores ranged from 71% to 92%, while AUC values ranged from 89.7% to 97.8%. Conclusion: Among various models compared, the ConvNeXt-L model exhibited superior performance. It effectively categorizes and visualizes pathological changes, providing essential assisted information for ophthalmologists and enhancing diagnostic accuracy and efficiency.

8.
Radiol Case Rep ; 19(8): 3316-3320, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38817638

RESUMO

The occurrence of triple kidneys, involving a normal kidney and a malrotation horseshoe kidney, is an extremely infrequent condition. This case report demonstrates a triple, mal-rotated horseshoe kidneys coexist with an upper junction stone, alongside a normal left kidney showing normal Doppler vascularity, as observed in an ultrasound examination for 18-year-old male complaints of diffuse periumbilical pain and burning micturition. Laboratory investigation revealed normal creatinine level, and presence of urinary tract infection. Management option for this case are antibiotic therapy and surgical intervention for horseshoe kidney stone. Regular monitoring of kidney function, other radiographic imaging studies, and follow-up to assess the efficacy of the treatment, and detect any further complications are essential.

9.
Vis Comput Ind Biomed Art ; 7(1): 8, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38625580

RESUMO

This study addresses a limitation of prior research on pectoralis major (PMaj) thickness changes during the pectoralis fly exercise using a wearable ultrasound imaging setup. Although previous studies used manual measurement and subjective evaluation, it is important to acknowledge the subsequent limitations of automating widespread applications. We then employed a deep learning model for image segmentation and automated measurement to solve the problem and study the additional quantitative supplementary information that could be provided. Our results revealed increased PMaj thickness changes in the coronal plane within the probe detection region when real-time ultrasound imaging (RUSI) visual biofeedback was incorporated, regardless of load intensity (50% or 80% of one-repetition maximum). Additionally, participants showed uniform thickness changes in the PMaj in response to enhanced RUSI biofeedback. Notably, the differences in PMaj thickness changes between load intensities were reduced by RUSI biofeedback, suggesting altered muscle activation strategies. We identified the optimal measurement location for the maximal PMaj thickness close to the rib end and emphasized the lightweight applicability of our model for fitness training and muscle assessment. Further studies can refine load intensities, investigate diverse parameters, and employ different network models to enhance accuracy. This study contributes to our understanding of the effects of muscle physiology and exercise training.

10.
Am J Ophthalmol Case Rep ; 34: 102041, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38544916

RESUMO

Purpose: The purpose of this case report is to outline the management of a 41-year-old female with pathological myopia and type II choroidal neovascularization (CNV) diagnosed by optical coherence tomography angiography (OCT-A) angio-B mode. Observations: The early detection of CNV with OCT-A angio-B mode and treatment with intra-vitreous injections of Bevacizumab contributed to the amelioration of her vision to 20/20, a better visual acuity than she had prior to treatment. Conclusions and importance: This case report suggests that an OCT-A scan may reveal the initial formation of abnormal vasculature before pathological changes are evident in structural OCT, allowing for prompt treatment and resolution in patients with myopic CNV.

11.
J Gastroenterol ; 59(6): 504-514, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38553657

RESUMO

BACKGROUND: Several preliminary reports have suggested the utility of ultrasound attenuation coefficient measurements based on B-mode ultrasound, such as iATT, for diagnosing steatotic liver disease. Nonetheless, evidence supporting such utility is lacking. This prospective study aimed to investigate whether iATT is highly concordant with magnetic resonance imaging (MRI)-based proton density fat fraction (MRI-PDFF) and could well distinguish between steatosis grades. METHODS: A cohort of 846 individuals underwent both iATT and MRI-PDFF assessments. Steatosis grade was defined as grade 0 with MRI-PDFF < 5.2%, grade 1 with 5.2% MRI-PDFF < 11.3%, grade 2 with 11.3% MRI-PDFF < 17.1%, and grade 3 with MRI-PDFF of 17.1%. The reproducibility of iATT and MRI-PDFF was evaluated using the Bland-Altman analysis and intraclass correlation coefficients, whereas the diagnostic performance of each steatosis grade was examined using receiver operating characteristic analysis. RESULTS: The Bland-Altman analysis indicated excellent reproducibility with minimal fixed bias between iATT and MRI-PDFF. The area under the curve for distinguishing steatosis grades 1, 2, and 3 were 0.887, 0.882, and 0.867, respectively. A skin-to-capsula distance of ≥ 25 mm was identified as the only significant factor causing the discrepancy. No interaction between MRI-logPDFF and MRE-LSM on iATT values was observed. CONCLUSIONS: Compared to MRI-PDFF, iATT showed excellent diagnostic accuracy in grading steatosis. iATT could be used as a diagnostic tool instead of MRI in clinical practice and trials. Trial registration This study was registered in the UMIN Clinical Trials Registry (UMIN000047411).


Assuntos
Fígado Gorduroso , Fígado , Imageamento por Ressonância Magnética , Ultrassonografia , Humanos , Feminino , Masculino , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Estudos Prospectivos , Ultrassonografia/métodos , Reprodutibilidade dos Testes , Adulto , Fígado Gorduroso/diagnóstico por imagem , Fígado Gorduroso/patologia , Fígado/diagnóstico por imagem , Fígado/patologia , Idoso , Curva ROC , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/patologia , Índice de Gravidade de Doença , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/patologia
12.
Ultrasonics ; 138: 107268, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38402836

RESUMO

Elastography is a promising diagnostic tool that measures the hardness of tissues, and it has been used in clinics for detecting lesion progress, such as benign and malignant tumors. However, due to the high cost of examination and limited availability of elastic ultrasound devices, elastography is not widely used in primary medical facilities in rural areas. To address this issue, a deep learning approach called the multiscale elastic image synthesis network (MEIS-Net) was proposed, which utilized the multiscale learning to synthesize elastic images from ultrasound data instead of traditional ultrasound elastography in virtue of elastic deformation. The method integrates multi-scale features of the prostate in an innovative way and enhances the elastic synthesis effect through a fusion module. The module obtains B-mode ultrasound and elastography feature maps, which are used to generate local and global elastic ultrasound images through their correspondence. Finally, the two-channel images are synthesized into output elastic images. To evaluate the approach, quantitative assessments and diagnostic tests were conducted, comparing the results of MEIS-Net with several deep learning-based methods. The experiments showed that MEIS-Net was effective in synthesizing elastic images from B-mode ultrasound data acquired from two different devices, with a structural similarity index of 0.74 ± 0.04. This outperformed other methods such as Pix2Pix (0.69 ± 0.09), CycleGAN (0.11 ± 0.27), and StarGANv2 (0.02 ± 0.01). Furthermore, the diagnostic tests demonstrated that the classification performance of the synthetic elastic image was comparable to that of real elastic images, with only a 3 % decrease in the area under the curve (AUC), indicating the clinical effectiveness of the proposed method.


Assuntos
Técnicas de Imagem por Elasticidade , Masculino , Humanos , Técnicas de Imagem por Elasticidade/métodos , Ultrassonografia/métodos , Área Sob a Curva
13.
Sci Rep ; 14(1): 3808, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360989

RESUMO

This study aimed to validate the concept of spatial gain sonography for quantifying texture-related echo intensity in B-mode ultrasound of skeletal muscle. Fifty-one bovine muscles were scanned postmortem using B-mode ultrasonography at varying fascicle probe angles (FPA). The relationship between mean gray values (MGV) and FPA was fitted with a sinusoidal and a linear function, the slope of which was defined as tilt echo gain (TEG). Macroscopic muscle cross sections were optically analyzed for intramuscular connective tissue (IMCT) content which was plotted against MGV at 0° FPA (MGV_00). MGV peaked at FPA 0°. Sine fits were superior to linear fits (adjusted r2-values 0.647 vs. 0.613), especially for larger FPAs. In mixed models, the pennation angle was related to TEG (P < 0.001) and MGV_00 (P = 0.035). Age was relevant for MGV_00 (P < 0.001), but not TEG (P > 0.10). The correlation between the IMCT percentage and MGV_00 was significant but weak (P = 0.026; adjusted r2 = 0.103). The relationship between fascicle probe angle and echo intensity in B-mode ultrasound can be modeled more accurately with a sinusoidal but more practically for clinical use with a linear fit. The peak mean gray value MGV_00 can be used to compare echo intensity across muscles without the bias of pennation angle.


Assuntos
Músculo Esquelético , Bovinos , Animais , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Ultrassonografia
14.
Clin Hemorheol Microcirc ; 87(1): 13-26, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38393892

RESUMO

BACKGROUND: Type 2 diabetes accelerates the loss of muscle mass and strength. Sarcopenia is also one of the chronic complications of diabetes. OBJECTIVE: To investigate the clinical value of B mode ultrasound (BMUS) and shear wave elastography (SWE) for predicting type 2 diabetic sarcopenia. METHODS: We recorded Skeletal Muscle Mass Index (ASMI), grip strength, muscle thickness (MT), pinna angle (PA), fascicle length (FL), and the difference of Young's modulus in the relaxed states and tense states (ΔSWE). The correlations between clinical indicators and ultrasound characteristics were compared. A diagnostic model of sarcopenia was developed to assess the independent correlates and evaluate the diagnostic efficacy of sarcopenia. RESULTS: ASMI was significantly and positively correlated with MT and ΔSWE (r = 0.826, 0.765, P < 0.01), and grip strength was significantly and positively correlated with MT and ΔSWE (r = 0.797, 0.818, P < 0.01). MT was the most significant predictor of sarcopenia (OR = 4.576, P < 0.001), and the cut-off value of MT was 11.4 mm (AUC: 0.952). CONCLUSION: BMUS and SWE can quantitatively assess muscle mass and strength, and are effective methods to predict the occurrence of sarcopenia in elderly patients with type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Técnicas de Imagem por Elasticidade , Sarcopenia , Humanos , Sarcopenia/diagnóstico por imagem , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Diabetes Mellitus Tipo 2/fisiopatologia , Técnicas de Imagem por Elasticidade/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Ultrassonografia/métodos , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiopatologia , Força da Mão
15.
Ultrasound Med Biol ; 50(5): 690-702, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38331698

RESUMO

OBJECTIVE: Point-scatterer detection plays a key role in medical ultrasound B-mode imaging. Speckle noise and insufficient spatial resolution are important factors affecting point-scatterer detection. To address this issue, normalized spatial autocorrelation in ultrasound B-mode imaging (NSACB) is proposed. METHODS: First, the acquired data are pre-processed by adding Gaussian white noise (GWN) with a certain signal-to-Gaussian white noise ratio (SGWNR). Next, normalized spatial autocorrelation is applied to the pre-processed data, and the data are divided into several new signals with different spatial lags. Then, the new signals are performed unsigned delay multiply and sum. Finally, the NSACB beamformed data are bandpass filtered by extracting the frequency component around twice the center frequency. Simulated and in vitro experiments were designed for validation. RESULTS: Simulations revealed that the lateral resolution of NSACB measured by the -6-dB mainlobe width can reach as high as 11.11% of delay and sum (DAS), 25.01% of filtered delay multiply and sum (F-DMAS) and 50% of LAG-FDMAS-SCF. The sidelobe level of the NSACB can be reduced at most by 28 dB. Experimental results of simple and complex scatterer phantoms indicate the image resolution of the proposed NSACB can even reach up to 18.76% of DAS, 27.28% of F-DMAS and 14.29% of LAG-FDMAS-SCF. Compared with these methods, the proposed NSACB can reduce the sidelobe level at least by 18 dB. CONCLUSION: Although the proposed method causes loss of the ability to observe hypo-echoic structures, these results suggest future work to determine the ability to detect breast microcalcifications, kidney stones, biopsy needle tracking and other scenarios requiring scatterer detection.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador/métodos , Ultrassonografia/métodos , Imagens de Fantasmas , Razão Sinal-Ruído
16.
Beilstein J Nanotechnol ; 15: 26-36, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38213571

RESUMO

We consider properties of dichroic antenna arrays on a silicon substrate with integrated cold-electron bolometers to detect radiation at frequencies of 210 and 240 GHz. This frequency range is widely used in cosmic microwave background experiments in space, balloon, and ground-based missions such as BICEP Array, LSPE, LiteBIRD, QUBIC, Simons Observatory, and AliCPT. As a direct radiation detector, we use cold-electron bolometers, which have high sensitivity and a wide operating frequency range, as well as immunity to spurious cosmic rays. Their other advantages are the compact size of the order of a few micrometers and the effect of direct electron cooling, which can improve sensitivity in typical closed-loop cycle 3He cryostats for space applications. We study a novel concept of cold-electron bolometers with two SIN tunnel junctions and one SN contact. The amplitude-frequency characteristics measured with YBCO Josephson Junction oscillators show narrow peaks at 205 GHz for the 210 GHz array and at 225 GHz for the 240 GHz array; the separation of these two frequency bands is clearly visible. The noise equivalent power level at an operating point in the current bias mode is 5 × 10-16 W/√Hz.

17.
Clin Hemorheol Microcirc ; 86(1-2): 51-61, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37638422

RESUMO

OBJECTIVES: To explore the technical and clinical evaluation of ultrasound-derived fat fraction (UDFF) measurement in adult patients in whom fatty liver was suspected. MATERIALS AND METHODS: In this prospective study, 41 participants were initially enrolled in our hospital between October 2022 and December 2022 and received UDFF assessment using Siemens ACUSON Sequoia system equipped with DAX transducer. UDFF measurement was performed three times to obtain UDFF values from each imaging location (V hepatic segment and VIII hepatic segment) per participant, and the depth (skin-to-capsule distance) was automatically measured. The echogenicity of liver tissue in B mode ultrasound (BMUS) was compared to the normal kidney tissue, and fatty liver was graded as mild (Grade 1), moderate (Grade 2), and severe (Grade 3). The median of the acquired overall median UDFF values was used for statistical analysis. All ultrasound examinations were performed by one of two radiologists (with 20 and 10 years of liver ultrasound imaging experience). RESULTS: Finally, UDFF measurement was successfully performed on 38 participants to obtain valid values, including 21 men with a median age of 40.0 years (interquartile range [IQR]: 23.0 - 58.5) and 17 women with a median age of 60.0 years (IQR: 29.5 - 67.0). Fatty liver was diagnosed by BMUS features in 47.4% (18/38) participants. Among all participants, the median UDFF value was 7.0% (IQR: 4.0 - 15.6). A significant difference in UDFF values was found between participants with fatty liver and without fatty liver (U = 7.0, P < 0.001), and UDFF values elevated as the grade of the fatty liver increased (P < 0.001). The median UDFF values from the three UDFF measurements obtained during each ultrasound examination showed excellent agreement (ICC = 0.882 [95% confidence interval: 0.833 - 0.919]). The Spearman correlation of UDFF values in different depths was moderate, with a rs value of 0.546 (P < 0.001). No significant differences in UDFF values were found between V hepatic segment and VIII hepatic segment (U = 684.5, P = 0.697). CONCLUSIONS: UDFF provides a novel non-invasive imaging tool for hepatic steatosis assessment with excellent feasibility.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Masculino , Adulto , Humanos , Feminino , Adulto Jovem , Pessoa de Meia-Idade , Estudos Prospectivos , Fígado/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Ultrassonografia/métodos , Imageamento por Ressonância Magnética/métodos
18.
J Med Ultrason (2001) ; 51(1): 29-37, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37971564

RESUMO

PURPOSE: Microglia, the brain's immune cells, play important roles in neuronal differentiation, survival, and death. The function of microglia is deeply related to the morphologies; however, it is too complex to observe conventionally and identify the condition of living microglia using optical microscopes. Herein, we proposed a new method to observe living cultured microglia and their reactivity to inflammation via the acoustic impedance mode of a scanning acoustic microscope. METHODS: Primary cultured microglia collected from rat pups exposed to acetamiprid, an insecticide, in utero were observed with both acoustic interface impedance mode (C-mode) and transparent three-dimensional impedance mode (B-mode). RESULTS: We characterized microglia into four types based on the results obtained from acoustic impedance, cytoskeletal information, and laser confocal imaging. Biphasic acoustic observation using B-mode and C-mode gave us information regarding the dynamic morphologies of living microglia treated with adenosine triphosphate (ATP) (600 µmol/L), which reflects distress signals from inflamed neurons. Acetamiprid exposure induced microglia response even in the neonatal period. ATP stimulus altered the shape and thickness of microglia with a change in the bulk modulus of the cell. Three-dimensional alteration with ATP stimulus could be observed only after biphasic acoustic observation using B-mode and C-mode. This acoustic observation was consistent with confocal observation using anti-Iba-1 and P2Y12 immunocytochemistry. CONCLUSION: This study demonstrated the adequacy of using a scanning acoustic microscope in analyzing microglia's shape, motility, and response to inflammation.


Assuntos
Microglia , Microscopia Acústica , Ratos , Animais , Impedância Elétrica , Microscopia Acústica/métodos , Acústica , Trifosfato de Adenosina/farmacologia , Inflamação/diagnóstico por imagem
19.
J Ultrasound Med ; 43(2): 397-403, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37948532

RESUMO

OBJECTIVES: The present study aims to explore the role of shear wave elastography (SWE) in the diagnosis of Peyronie disease (PD). METHODS: A total of 59 PD patients and 59 age-matched healthy adult men were included in this study. The B-mode ultrasound (US) and SWE were performed for all subjects, and the Young modulus (YM) values of the corresponding regions of the penis in the PD and control groups were recorded and compared. RESULTS: The mean age of the included PD patients and age-matched controls was 53.81 years (SD 9.52, range 32-73). On B-mode US evaluation, 41 (69.5%) of 59 included PD patients were found to have penile plaques, and the remaining 18 (30.5%) patients had no evidence of penile plaque. After evaluation using SWE, the YM values in the penile plaque region of these 41 patients with penile dysplasia were found to be significantly higher (60.29 kPa ± 19.95) than those outside the plaque (in the same patient) (21.05 kPa ± 4.58) and in the same penile region of the control group (20.59 kPa ± 4.65) (P < .001). In the remaining 18 PD patients, the results showed that the YM value of the abnormal penile region in the PD patients (56.67 kPa ± 13.52) was significantly higher than the YM value outside the abnormal penile region in the same patients (22.79 kPa ± 4.31) and in the same penile region in the control group (19.87 kPa ± 3.48) (P < .001; P < .001). CONCLUSIONS: In conclusion, this study showed that SWE as a non-invasive technique is useful in identifying and differentiating penile plaques in PD patients and is a simple, rapid and complementary method to B-mode US.


Assuntos
Técnicas de Imagem por Elasticidade , Induração Peniana , Placa Aterosclerótica , Masculino , Adulto , Humanos , Pessoa de Meia-Idade , Técnicas de Imagem por Elasticidade/métodos , Induração Peniana/diagnóstico por imagem , Ultrassonografia , Módulo de Elasticidade , Interpretação de Imagem Assistida por Computador/métodos
20.
J Ultrasound Med ; 43(1): 109-114, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37772458

RESUMO

OBJECTIVES: Shear wave elastography (SWE) is increasingly used in breast cancer diagnostics. However, large, prospective, multicenter data evaluating the reliability of SWE is missing. We evaluated the intra- and interobserver reliability of SWE in patients with breast lesions categorized as BIRADS 3 or 4. METHODS: We used data of 1288 women at 12 institutions in 7 countries with breast lesions categorized as BIRADS 3 to 4 who underwent conventional B-mode ultrasound and SWE. 1243 (96.5%) women had three repetitive conventional B-mode ultrasounds as well as SWE measurements performed by a board-certified senior physician. 375 of 1288 (29.1%) women received an additional ultrasound examination with B-mode and SWE by a second physician. Intraclass correlation coefficients (ICC) were calculated to examine intra- and interobserver reliability. RESULTS: ICC for intraobserver reliability showed an excellent correlation with ICC >0.9, while interobserver reliability was moderate with ICC of 0.7. There were no clinically significant differences in intraobserver reliability when SWE was performed in lesions categorized as BI-RADS 3 or 4 as well as in histopathologically benign or malignant lesions. CONCLUSION: Reliability of additional SWE was evaluated on a study cohort consisting of 1288 breast lesions categorized as BI-RADS 3 and 4. SWE shows an excellent intraobserver reliability and a moderate interobserver reliability in the evaluation of solid breast masses.


Assuntos
Neoplasias da Mama , Técnicas de Imagem por Elasticidade , Humanos , Feminino , Masculino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Ultrassonografia Mamária , Estudos Prospectivos , Reprodutibilidade dos Testes , Mama/diagnóstico por imagem , Mama/patologia , Sensibilidade e Especificidade , Diagnóstico Diferencial
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