Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 129
Filter
1.
Front Oncol ; 14: 1390342, 2024.
Article in English | MEDLINE | ID: mdl-39045562

ABSTRACT

Objectives: To explore the utility of gray-scale ultrasound (GSUS) and mammography (MG) for radiomic analysis in distinguishing between breast adenosis and invasive ductal carcinoma (IDC). Methods: Data from 147 female patients with pathologically confirmed breast lesions (breast adenosis: 61 patients; IDC: 86 patients) between January 2018 and December 2022 were retrospectively collected. A training cohort of 113 patients (breast adenosis: 50 patients; IDC: 63 patients) diagnosed from January 2018 to December 2021 and a time-independent test cohort of 34 patients (breast adenosis: 11 patients; IDC: 23 patients) diagnosed from January 2022 to December 2022 were included. Radiomic features of lesions were extracted from MG and GSUS images. The least absolute shrinkage and selection operator (LASSO) regression was applied to select the most discriminant features, followed by logistic regression (LR) to construct clinical and radiomic models, as well as a combined model merging radiomic and clinical features. Model performance was assessed using receiver operating characteristic (ROC) analysis. Results: In the training cohort, the area under the curve (AUC) for radiomic models based on MG features, GSUS features, and their combination were 0.974, 0.936, and 0.991, respectively. In the test cohort, the AUCs were 0.885, 0.876, and 0.949, respectively. The combined model, incorporating clinical and all radiomic features, and the MG plus GSUS radiomics model were found to exhibit significantly higher AUCs than the clinical model in both the training cohort and test cohort (p<0.05). No significant differences were observed between the combined model and the MG plus GSUS radiomics model in the training cohort and test cohort (p>0.05). Conclusion: The effectiveness of radiomic features derived from GSUS and MG in distinguishing between breast adenosis and IDC is demonstrated. Superior discriminatory efficacy is shown by the combined model, integrating both modalities.

2.
Biomedicines ; 12(4)2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38672093

ABSTRACT

Echolucency, a measure of plaque instability associated with increased cardiovascular risk, can be assessed in both the carotid plaque and the plaque-free common carotid intima-media (IM) complex as a gray-scale median (plaque-GSM and IM-GSM, respectively). The impact of specific vascular risk factors on these two phenotypes remains uncertain, including the nature and extent of their influence. This study aims to seek the determinants of plaque-GSM and IM-GSM. Plaque-GSM and IM-GSM were measured in subjects from the IMPROVE study cohort (aged 54-79, 46% men) recruited in five European countries. Plaque-GSM was measured in subjects who had at least one IMTmax ≥ 1.5 mm (n = 2138), whereas IM-GSM was measured in all subjects included in the study (n = 3188). Multiple regression with internal cross-validation was used to find independent predictors of plaque-GSM and IM-GSM. Plaque-GSM determinants were plaque-size (IMTmax), and diastolic blood pressure. IM-GSM determinants were the thickness of plaque-free common carotid intima-media complex (PF CC-IMTmean), height, systolic blood pressure, waist/hip ratio, treatment with fibrates, mean corpuscular volume, treatment with alpha-2 inhibitors (sartans), educational level, and creatinine. Latitude, and pack-yearscode were determinants of both plaque-GSM and IM-GSM. The overall models explain 12.0% of plaque-GSM variability and 19.7% of IM-GSM variability. A significant correlation (r = 0.51) was found between plaque-GSM and IM-GSM. Our results indicate that IM-GSM is a weighty risk marker alternative to plaque-GSM, offering the advantage of being readily measurable in all subjects, including those in the early phases of atherosclerosis where plaque occurrence is relatively infrequent.

3.
Quant Imaging Med Surg ; 14(2): 1541-1552, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38415130

ABSTRACT

Background: The European League Against Rheumatism-Outcomes Measures in Rheumatology (EULAR-OMERACT) recommend only scanning dorsal spaces for scoring ultrasound-detected hand synovitis. This study evaluated the efficiency of the combined scoring system only depending on dorsal joint spaces synovitis in diagnosing and evaluating ultrasound-detected hand synovitis. Methods: The data of 56 patients who underwent hand joint ultrasonography exams in the Ultrasound Department of West China Hospital, Sichuan University were prospectively collected. The participants formed a random series. The images of each patient included gray-scale (GS) and power Doppler (PD) images of bilateral first to fifth metacarpophalangeal joints (MCP) and the thumb and second to fifth proximal interphalangeal joints (IP). The synovial thickness was measured quantitatively in GS images, and the synovial GS scores in the dorsal joint spaces and PD scores in the dorsal and volar joint spaces were calculated according to the combined EULAR-OMERACT scoring system. Results: The detection rate of synovitis in the first to fifth MCP, thumb and second to fifth proximal IP synovitis were 41.4% (232/560) and 33.9% (190/560), respectively. The sensitivity of only inspecting the dorsal joint spaces with GS ultrasound was 79.3% for MCP and 52.6% for the thumb and second to fifth proximal IPs. The PD scores were higher in the dorsal joint spaces than in the volar joint spaces (P value <0.001). The combined scores were higher than either the GS or PD scores alone in the dorsal joint spaces (P value of the combined scores vs. GS scores =0.001; P value of the combined scores vs. PD scores <0.001). Conclusions: Adopting the EULAR-OMERACT combined scoring standard is recommended to evaluate ultrasound-detected hand synovitis, as determined by the highest value of the GS scores or the PD scores. More specifically, PD scores can mainly be used to appraise the dorsal joint spaces. However, GS scores should be used to evaluate both the dorsal joint spaces and the volar joint spaces.

4.
Quant Imaging Med Surg ; 14(2): 1994-2007, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38415155

ABSTRACT

Background: Research has shown that carotid intima-media thickness (CIMT) could help to predict carotid plaque (CP) progression in patients with mild carotid stenosis. However, the debate continues as to the value of carotid intima thickness (CIT) in monitoring the development of CP in patients with severe carotid stenosis. This study sought to evaluate the relationships between CIT and the ultrasonic characteristics of CP and to analyze the value of CIT and the ultrasonic parameters of CP in assessing plaque vulnerability in advanced human carotid atherosclerosis. Methods: A total of 55 individuals who underwent carotid endarterectomy (CEA) were included in the study (mean age: 65±7 years; female: 9.1%). CIMT and CIT were examined at the common carotid artery (CCA). Plaque textural features, such as the gray-scale median (GSM), superb microvascular imaging (SMI) level, and total plaque area (TPA), were also identified. A Spearman correlation coefficient analysis was performed to examine the relationship between CIT and the ultrasonic parameters of CP. The CIT of various plaque types was compared. Receiver operating characteristic (ROC) curves were used to analyze the diagnostic values of the ultrasound characteristics to evaluate CP vulnerability. Results: The mean CIT of all the participants was 0.382±0.095 mm, the mean CIT of the participants with stable plaques was 0.328±0.031 mm, and the mean CIT of participants with vulnerable plaques was 0.424±0.106 mm (P<0.001). CIT was associated with the SMI level (Spearman's correlation coefficient: r=0.392, P=0.005), TPA (Spearman's correlation coefficient: r=0.337, P=0.012). Patients with thicker CIT had larger lipid cores, higher levels of plaque vulnerability, and more intraplaque hemorrhages (IPHs). The areas under the ROCs (AUCs) with 95% confidence interval (CI) for CIMT, CIT, the SMI level, the GSM, the TPA, and the combined model for identifying vulnerable plaques were 0.673 (0.533-0.793), 0.849 (0.727-0.932), 0.771 (0.629-0.879), 0.669 (0.529-0.790), 0.858 (0.738-0.938), and 0.949 (0.854-0.990), respectively. Conclusions: CIT was associated with both the histology and ultrasonic features of CP. CIT may be helpful in the detection of severe CP development.

5.
J Ultrason ; 24(94): 1-7, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38343787

ABSTRACT

Aim: Ultrasound elastography is a simple non-invasive method for measuring tissue elasticity in relation to tissue fibrosis. The aim of this study was to compare echogenicity, volume and shear wave velocities of undescended vs normally descended testes. Material and methods: Sixty-six boys with undescended testes were included in this study. The median age range was 35.5 (10-118) months old. The cases included in this prospective study consisted of 66 patients with non-operated undescended testes, with 51 of them being affected unilaterally and 15 affected bilaterally, as diagnosed by physical examination. The control group consisted of 31 healthy boys without any particular health problems. This prospective study was performed by gray-scale ultrasonography and shear wave elastography in boys with undescended testes and healthy testes. The testicular volumes were established by ultrasound measurement, the echogenicity and shear wave elastography values were measured in boys with unilateral and bilateral undescended testes, and the results were compared with healthy boys' testes and their contralateral testes. The stiffness values were recorded for speed (m/s) and elasticity (kPa), and the stiffness values of undescended testes were compared with the healthy control group. Results: Echogenicity values were lower in the bilateral undescended testes group than in the healthy group, and the healthy group's echogenicity was normal (p <0.001). The ROC curve was used to identify a cut-off shear wave elastography value for predicting decreased testicular echogenicity by using average shear wave elastography values. The area under the curve for the undescended testes was 0.78 (95% CI: 0.70-0.85, sensitivity 83.7%, specificity 68.7%, p <0.001), with an average shear wave elastography value of 2.32 (m/s) for above the cut-off point indicates. This was found to be significantly associated with reduced echogenicity on gray-scale ultrasonography, suggesting that it may be correlated with fibrosis developing in patients with undescended testes. Conclusion: The study provides interesting findings in that it proposes an alternative non-invasive method for the assessment of testicular tissue in undescended testes. We used shear wave elastography to compare the stiffness of normal testes in both heathy patients and in the contralateral healthy testes of boys with undescended testes, with the values obtained for the undescended testes reflecting the level of fibrosis of the parenchyma. Another outcome of this study was observed in patients with unilateral undescended testes, where the normally descended testes showed increased shear wave elastography values, which could be an early indication of parenchymal change.

6.
J Clin Ultrasound ; 52(1): 51-58, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37915163

ABSTRACT

OBJECTIVE: To investigate the efficacy of the ultrasonic nodule to muscle gray scale ratio as a predictive tool for distinguishing between benign and malignant thyroid nodules. METHODS: A retrospective study was undertaken at the First People's Hospital of Hangzhou, affiliated with the Zhejiang University School of Medicine, analyzing ultrasound and pathological data of patients with thyroid nodules between May 2020 and December 2022. The study extracted ultrasound features of nodules and employed univariate and multivariate logistic regression analyses to identify independent risk factors for malignant tumors in the nodules. Subsequently, a predictive model for distinguishing benign and malignant thyroid nodules was developed. RESULTS: A total of 466 patients were included in this retrospective study, of which 275 cases were malignant tumors. Univariate and multivariate logistic regression analyses showed that the nodular-muscle gray-scale ratio, nodule diameter, margin status, aspect ratio, and calcification were closely related to thyroid malignant tumors. The area under the curve (AUC) of training group was 0.832, with a sensitivity, specificity, and accuracy of 85.5%, 67.4%, and 76.6%, respectively. The AUC of the external validation group was 0.819, with a sensitivity, specificity, and accuracy of 76.4%, 74.5%, and 75.7%, respectively. The calibration and decision curves showed that the model had good diagnostic value. CONCLUSION: The research findings indicate that ratio is significantly associated with the malignant nature of thyroid nodules. The application of a line chart model based on these parameters exhibits a high level of predictive performance.


Subject(s)
Thyroid Neoplasms , Thyroid Nodule , Humans , Thyroid Nodule/diagnostic imaging , Thyroid Nodule/pathology , Retrospective Studies , Thyroid Neoplasms/diagnostic imaging , Thyroid Neoplasms/pathology , Ultrasonography/methods , Diagnosis, Differential , Muscles/pathology , Sensitivity and Specificity
7.
Clin Hemorheol Microcirc ; 87(1): 55-65, 2024.
Article in English | MEDLINE | ID: mdl-38160348

ABSTRACT

BACKGROUND: Hepatic sarcomatoid carcinoma (HSC) is a rare malignancy of the liver. The ultrasound and clinical features of HSC have not been determined. OBJECTIVE: To investigate and compare the ultrasound and clinical features of HSC and hepatocellular carcinoma (HCC), and to reveal the valuable features of HSC. METHODS: The ultrasound features and clinical data of pathologically proven HSC (n = 37) were compared with HCC (n = 92) in a matching ratio of 1:4 using the propensity score (age, gender and tumor size). RESULTS: The HSC patients were more likely to accompany with clinical symptoms and vascular invasion than HCC patients (40.5% vs 17.4%, 24.3% vs 6.5%, P < 0.05). The size of HSCs was significantly larger than that of HCCs (P < 0.05). The proportion of patients with elevated alpha-fetoprotein was significantly lower in HSC (35.1% vs 54.3%, P < 0.05). On gray-scale ultrasound images, the HSCs were more likely to demonstrate as indistinct margin and irregular shape lesions compared to HCCs (78.4% vs 48.8%; 70.3% vs 23.9%, P < 0.05). Under color Doppler flow imaging (CDFI), the blood flow signals were more frequently detected in HSC lesions (75.7% vs 56.5%, P < 0.05). Resistance index (RI) was higher in HSCs than in HCCs [0.78 (0.70,0.82) vs 0.70 (0.62,0.76), P < 0.05]. On contrast-enhanced ultrasound (CEUS), HSCs mainly showed entirety heterogeneous hyper-enhancement (48.6%), entirety homogeneous enhancement (18.9%), peripheral and internal septal enhancement (18.9%). The incidence of non-enhanced areas inside HSC lesions was higher than that inside HCC lesions (56.8% vs 31.5%, P < 0.05). During the portal venous and late phases, most of the lesions revealed hypo-enhancement in both groups, whereas earlier washout was observed in HSCs [43.0 s (30.5,58.0) vs 60.0 s (46.3,100.0), P < 0.05]. CONCLUSIONS: CEUS features are useful in preoperative and non-invasive differentiation of hepatic sarcomatoid carcinoma and hepatocellular carcinoma.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Ultrasonography , Humans , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/pathology , Carcinoma, Hepatocellular/diagnostic imaging , Carcinoma, Hepatocellular/pathology , Male , Female , Middle Aged , Ultrasonography/methods , Contrast Media , Aged , Adult
8.
Small ; : e2306802, 2023 Dec 08.
Article in English | MEDLINE | ID: mdl-38063817

ABSTRACT

Two-photon direct laser writing enables the fabrication of shape-changing microstructures that can be exploited in stimuli responsive micro-robotics and photonics. The use of Liquid Crystalline Networks (LCN) allows to realize 3D micrometric objects that can contract along a specific direction in response to stimuli, such as temperature or light. In this paper, the fabrication of free-standing LCN microstructures is demonstrated as graphical units of a smart tag for simple physical and optical encryption. Using an array of identical pixels, information can be hidden to the observer and revealed only upon application of a specific stimulus. The reading mechanism is based on the shape-change of each pixel under stimuli and their color that combine together in a two-level encryption label. Once the stimulus is removed, the pixels recover their original shape and the message remains completely hidden. Therefore, an opto-mechanical equivalent of an "invisible ink" is realized. This new concept paves the way for introducing enhanced functionalities in smart micro-systems within a single lithography step, spanning from storage devices with physical encryption to complex motion actuators.

9.
Cancers (Basel) ; 15(22)2023 Nov 08.
Article in English | MEDLINE | ID: mdl-38001591

ABSTRACT

BACKGROUND: Ultrasonography (US) represents the gold standard imaging method for the assessment of testicular lesions (TL). The gray-scale (GSUS) and color-Doppler (CDUS) ultrasound examination allow sonographers to investigate the size, margins, echotexture, and vascular features of TLs with the aim to differentiate benign from malignant lesions. Recently, the use of contrast-enhanced US (CEUS) and sonoelastography (SE) has led to further improvements in the differential diagnosis of TL. Although GSUS and CDUS are often sufficient to suggest the benign or malignant nature of the TL, CEUS can be decisive in the differential diagnosis of unclear findings, while SE can help to strengthen the diagnosis. The contemporary combination of GSUS, CDUS, CEUS, and SE has led to a new diagnostic paradigm named multiparametric US (mp-US), which is able to provide a more detailed characterization of TLs than single techniques alone. This narrative and pictorial review aimed to describe the mp-US appearance of several TLs. METHODS: An extensive Medline search was performed to identify studies in the English language focusing on the mp-US evaluation of TLs. RESULTS: A practical mp-US "identity card" and iconographic characterization of several benign and malignant TLs is provided herein. CONCLUSIONS: The mp-US characterization of TL reported herein can be useful in daily clinical practice.

10.
Front Physiol ; 14: 1197503, 2023.
Article in English | MEDLINE | ID: mdl-37781221

ABSTRACT

Introduction: While shear modulus has been used as an index of muscle elongation, high costs prevent its general adoption. A more general indicator that can quantify muscle elongation non-invasively is needed to develop effective methods for stretching each muscle. The purpose of this study was to determine whether the echo intensity of the muscle changes with muscle elongation compared with the shear modulus. Methods: Sixteen healthy males (24.1 ± 2.8 years) participated in the study. Shear modulus and echo intensity of the medial gastrocnemius were assessed at 20° and 10° of ankle plantar-flexion, and 0°, 10°, and 20° of ankle dorsiflexion (presented as -20°, -10°, and 0°, +10°, +20°, respectively). Shear modulus was measured using ultrasound shear wave elastography. The echo intensity was quantified using the average grayscale value of a given region of interest (RoI) in longitudinal and transverse B-mode images. Grayscale analysis was performed using two RoIs: one which included as much of the muscle as possible (maximum RoI), and a rectangular one whose size and depth was identical for all images (rectangular RoI). Pearson's correlation coefficients between either the shear modulus or echo intensity and the ankle angle and between the echo intensity and shear modulus were calculated separately for each participant. Results: Average Pearson's correlation coefficient between shear modulus and ankle angle of the participants was 0.904. The average Pearson's correlation coefficients between the echo intensity and ankle angle were estimated to be 0.797 and 0.222 for the maximum RoI and 0.698 and 0.323 for the rectangular RoI in the longitudinal and transverse images, respectively. The average Pearson's correlation coefficients between the echo intensity and shear modulus were 0.684 and 0.514 for the maximum RoI, and 0.611 and 0.409 for rectangular RoI in the longitudinal and transverse images, respectively. Discussion: The results indicate that the echo intensity in the longitudinal image of the gastrocnemius, especially when assessed using the maximum RoI, increased with muscle elongation by passive ankle dorsiflexion. Therefore, assessment of the echo intensity using the maximum RoI in the longitudinal image might be useful for quantifying the muscle elongation.

11.
Comput Biol Med ; 165: 107409, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37672923

ABSTRACT

Medical imaging techniques have been widely used for diagnosis of various diseases. However, the imaging-based diagnosis generally depends on the clinical skill of radiologists. Computer-aided diagnosis (CAD) can help radiologists improve diagnostic accuracy as well as the consistency and reproducibility. Although convolutional neural network (CNN) has shown its feasibility and effectiveness in CAD, it generally suffers from the problem of small sample size when training CAD models. Nowadays, self-supervised learning (SSL) has shown its effectiveness in the field of medical image analysis, especially when there are only limited training samples. However, the backbone of downstream task sometimes cannot be well pre-trained in the conventional SSL framework due to the limitation of the pretext task and fine-tuning mechanism. In this work, an improved SSL framework, named Hybrid-supervised Bidirectional Transfer Networks (HBTN), is proposed to improve the performance of CAD models. Specifically, a novel Gray-Scale Image Mapping (GSIM) task is developed, which still takes the widely used image restoration task in SSL as the pretext task, but further embeds the class label information into it to improve discriminative feature learning of its corresponding network model. The proposed HBTN then integrates two different network architectures, i.e. the image restoration network for the pretext task and the classification network for the downstream task, into a unified hybrid-supervised learning (HSL) framework. It jointly trains both networks and collaboratively transfers the knowledge between each other. Consequently, the performance of downstream network is thus improved. The proposed HBTN is evaluated on two medical image datasets for CAD tasks. The experimental results indicate that HBTN outperforms the conventional SSL algorithms for CAD with limited training samples.

12.
Dent J (Basel) ; 11(8)2023 Aug 11.
Article in English | MEDLINE | ID: mdl-37623289

ABSTRACT

Aim of this study was to demonstrate the diagnostic ability to differentiate odontogenic keratocysts (OKCs) from ameloblastomas (AMs) based on computed tomography (CT) or cone beam computed tomography (CBCT) scans. Preoperative CT and CBCT scans from 2004 to 2019 of OKCs and AMs were analyzed in 51 participants. Lesions were three-dimensionally (3D) assessed and Hounsfield units (HU) as well as gray scale values (GSV) were quantified. Calculated HU spectra were compared within the same imaging modalities using unpaired t-tests and correlated with participants characteristics by calculating Pearsons correlation coefficients. Within the CT scans, AMs had highly significantly higher HU values compared to OKCs (43.52 HU and 19.79 HU, respectively; p < 0.0001). Analogous, within the CBCT scans, AMs had significantly higher GSV compared to OKCs (-413.76 HU and -564.76 HU, respectively; p = 0.0376). These findings were independent from participants' gender and age, anatomical site, and lesion size, indicating that the HU- and GSV-based difference reflects an individual configuration of the lesion. HU and GSV spectra calculated from CT and CBCT scans can be used to discriminate between OKCs and AMs. This diagnostic approach represents a faster and non-invasive option for preoperative diagnosis of such entities and has potential to facilitate therapeutic decision making.

13.
Dentomaxillofac Radiol ; 52(7): 20230033, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37427600

ABSTRACT

OBJECTIVE: To characterize different allogeneic and xenogeneic soft tissue graft substitutes and to assess their echo intensity and grayscale texture-related outcomes by using high-frequency ultrasonography (HFUS). METHODS: Ten samples from each of the following biomaterials were scanned using HFUS: bilayered collagen matrix (CM), cross-linked collagen matrix (CCM), multilayered cross-linked collagen matrix (MCCM), human-derived acellular dermal matrix (HADM), porcine-derived acellular dermal matrix (PADM), collagen tape dressing (C) and dental implants (IMPs). The obtained images were then imported in a commercially available software for grayscale analysis. First-order grayscale outcomes included mean echo intensity (EI), standard deviation, skewness, and kurtosis, while second-order grayscale outcomes comprised entropy, contrast, correlation, energy and homogeneity derive from the gray-level co-occurrence matrix analysis. Descriptive statistics were performed for visualization of results, and one-way analysis of variance with Bonferroni post-hoc tests were performed to relative assessments of the biomaterials. RESULTS: The statistical analysis revealed a statistically significant difference among the groups for EI (p < .001), with the group C showing the lowest EI, and the IMP group presenting with the greatest EI values. All groups showed significantly higher EI when compared with C (p < .001). No significant differences were observed for energy, and correlation, while a statistically significant difference among the groups was found in terms of entropy (p < 0.01), contrast (p < .001) and homogeneity (p < .001). IMP exhibited the highest contrast, that was significantly higher than C, HADM, PADM, CCM and CM. CONCLUSIONS: HFUS grayscale analysis can be applied to characterize the structure of different biomaterials and holds potential for translation to in-vivo assessment following soft tissue grafting-related procedures.


Subject(s)
Biocompatible Materials , Dental Implants , Humans , Swine , Animals , Pilot Projects , Collagen
14.
Micromachines (Basel) ; 14(3)2023 Mar 19.
Article in English | MEDLINE | ID: mdl-36985091

ABSTRACT

Gray scale consistency in pixels was extremely important for electrowetting displays (EWDs). However, traditional electrowetting display driving waveforms could not obtain a pixel aperture ratio consistency, which led to the occurrence of gray inconsistency even if it was the same driving waveform. In addition, the oil backflow caused by charge trapping could not be sustained. Therefore, a multi-direct current (DC) overdriving waveform for gray scale consistency was proposed in this paper, which could effectively improve the performance of EWDs. The driving waveform was divided into a start-up driving phase and a stable driving phase. The stable driving phase was composed of a square wave with a duty cycle of 79% and a frequency of 43 Hz. Subsequently, an overdriving pulse was also introduced in the stable driving phase. The multi-DC driving waveform for gray scale consistency was applied to a thin film transistor-electrowetting display (TFT-EWD). The average difference between increasing driving voltage and decreasing driving voltage was only 2.79%. The proposed driving waveform has an aperture ratio of 3.7 times at low voltages compared to DC driving.

15.
Mikrochim Acta ; 190(2): 48, 2023 01 09.
Article in English | MEDLINE | ID: mdl-36622479

ABSTRACT

Due to their low cost, simplicity, and pump-free liquid transport properties, colorimetric assays on paper spots and microfluidic paper-based analytical devices (µPADs) are regarded as useful tools for point-of-care testing (POCT). However, for certain types of colorimetric assays, the "non-transparent" and "white" characters of paper can be a disadvantage. In this work, the possibilities of using cellophane as an alternative platform for colorimetric assays have been investigated. Cellophane is a low cost and easy-to-handle transparent film made of regenerated cellulose. Owing to its hydrophilic character, cellophane-based microfluidic channels fabricated through a print-cut-laminate approach enabled pump-free liquid transport into multiple detection areas, similar to µPADs. In addition, the water absorption characteristics of cellophane allowed the stable immobilization of water-soluble colorimetric indicators without any surface modification or additional reagents. The transparency of cellophane provides possibilities for simple background coloring of the substrates, increasing the dynamic signal range for hue-based colorimetric assays, as demonstrated for two model assays targeting H2O2 (46-fold increase) and creatinine (3.6-fold increase). Finally, a turbidity detection-based protein assay was realized on black background cellophane spots. The lowest limits of detection achieved with the cellophane-based devices were calculated as 7 µM for H2O2, 2.7 mg dL-1 for creatinine, and 3.5 mg dL-1 for protein (human serum albumin).


Subject(s)
Microfluidic Analytical Techniques , Microfluidics , Humans , Cellophane , Colorimetry , Creatinine , Hydrogen Peroxide , Water
16.
Article in English | WPRIM (Western Pacific) | ID: wpr-988676

ABSTRACT

Background@#Gestational trophoblastic neoplasia (GTN) presents as vascular mass of varying morphology on ultrasound and confirmed through quantitative serum β subunit human chorionic gonadotrophin (β‑hCG). In regions with limited access to β‑hCG, ultrasound plays a crucial role in the initial diagnosis for timely management.@*Objectives@#This study aimed to investigate the associations between ultrasound vascular morphologic features, serum β‑hCG levels, and histopathology in GTN cases.@*Methodology@#A cross‑sectional review was conducted on 113 cases with ultrasound impression of GTN over an 8‑year period. The patient data were extracted from case records, and ultrasound images were categorized based on the distinct features. Associations with β‑hCG levels and histopathology were analyzed using the Chi‑square test and Mann–Whitney U‑test. Statistical significance was set at P < 0.05.@*Results@#A significant association was observed between ultrasound category and serum β‑hCG (P < 0.0001). The compact and diffuse types were more prevalent with β‑hCG levels between 104 to <105 mIU/mL, while the lacunar type was common among patients with ≥105 mIU/mL. However, there was no significant association between ultrasound categories and mean β‑hCG levels. Regarding histopathology, the lacunar type was more common in invasive moles, whereas the compact and diffuse types tended to be seen with choriocarcinoma, although these were not statistically significant (P = 0.182).@*Conclusions@#Morphologic types of GTN by gray scale and Doppler ultrasound vary across the different levels of serum β‑hCG and may suggest the histopathological diagnosis. This study provides valuable insights into the ultrasonographic characteristics of GTN, which can aid in its diagnosis and management.


Subject(s)
Gestational Trophoblastic Disease , Ultrasonography, Doppler
17.
Front Vet Sci ; 9: 982560, 2022.
Article in English | MEDLINE | ID: mdl-36337187

ABSTRACT

Objective: To evaluate the accuracy of end-on fluoroscopy in predicting implant position in relation to the vertebral canal in the canine thoracolumbar vertebral column. Study design: In vitro imaging and anatomic study. Animals: Canine cadaveric thoracolumbar vertebral columns (n = 5). Methods: Smooth Steinmann pins were inserted bicortically into the thoracolumbar vertebral columns between T10 and L7 using recommended insertion angles. Penetration of the spinal canal was not strictly avoided. After pin placement, end-on fluoroscopy images were obtained of each pin. Pin position was subsequently assessed by four evaluators and determined to either being out of the vertebral canal or in, with the latter being additionally divided into partially or completely penetrating the canal. To assess potential differences in modalities, fluoroscopy images were gray-scale inverted and evaluated again later by the same four individuals. Correct identification of pin position in relationship to the vertebral canal was assessed for both fluoroscopy images. Anatomic preparation of the spines was used for verification of pin position in relation to the spinal canal. Some data from this study were compared with historical data on accuracy using orthogonal radiography and computed tomography (CT). Results: Overall sensitivity and specificity of F to detect vertebral canal penetration was 98.8 % (95% confidence interval (CI), 96.0-99.6) and 98.0% (95% CI, 77.0-99.9), respectively. For Fi, sensitivity and specificity were 97.0% (95% CI, 91.5-99.0) and 98.5% (95% CI, 81.5-99.9) respectively. F exceeded Fi for the sensitivity of detecting pin penetration into the vertebral canal (p = 0.039) but specificities were not different (p = 0.585). When comparing to historical data, the overall accuracy of end-on fluoroscopy (F) and inverted fluoroscopy (Fi) was statistical better than conventional radiographic assessment (p < 0.001). Conclusion: End-on fluoroscopy is a highly accurate method for the assessment of pin position in relationship to the thoracolumbar spinal canal in cadaveric dogs. Clinical significance: End-on fluoroscopy, with or without inversion, is accurate in identifying vertebral canal violation by bicortically placed Steinmann pins. When CT is not available, end-on fluoroscopy might be a valuable imaging modality to determine pin position in the canine vertebral column.

18.
Beijing Da Xue Xue Bao Yi Xue Ban ; 54(5): 991-999, 2022 Oct 18.
Article in Chinese | MEDLINE | ID: mdl-36241243

ABSTRACT

OBJECTIVE: To analyze the feasibility of using vascular plaque quantification (VPQ) to evaluate carotid atherosclerotic plaques and to observe the effect of statins on carotid atherosclerotic plaques. METHODS: Patients with carotid plaques from January 2016 to September 2018 in Peking University First Hospital Neurology Department were recruited and underwent three-dimonsional ultrasound (3DUS). Their gray scale median (GSM) and other parameters of carotid plaques were measured with VPQ. The patients were divided into low GSM group (GSM < 40) and high GSM group (GSM≥40). The clinical characteristics and plaque characteristics of the patients in the two groups were compared to analyze the stability of plaques. According to whether taking statins or not, the patients were further divided into statin group and non-statin group, plaque GSM and other parameters of their carotid plaques were measured and the changes of carotid plaques at the end of 3 months and 2 years were observed. RESULTS: A total of 120 patients were enrolled, including 79 males and 41 females, with an average age of (65.39±9.11) years. The patients were divided into low GSM group (31 cases) (GSM < 40) and high GSM group (89 cases) (GSM≥40). The stenosis of the lumen in the low GSM group was more severe (the area stenosis rate was 41.32%±21.37% vs. 29.79%±17.16%, P < 0.05). The nor-malized wall index (NWI) of plaque in low GSM group was significantly higher than that in high GSM group (0.61 ±0.14 vs. 0.52±0.12, P < 0.01). A total of 77 patients, including 51 males and 26 females, aged (64.96±9.58) years, were enrolled to observe the statin effects on carotid plaque. They were divided into statin group (n=56) and non-statin group (n=21) according to whether taking statins or not. At the baseline and 3-month follow-up, there were no significant differences in carotid plaque volume, area, degree of luminal stenosis and GSM between the two groups (P>0.05). At the end of the 2-year follow-up, GSM increased in the statin group [median 10.00 (2.00, 28.00)] but decreased in the non-statin group [median -7.00 (-11.00, 5.50)], with a statistically significant difference between the two groups (P < 0.01). There was no significant increase in carotid plaque volume in the statin group, while there was a slight increase in the non-statin group, but there was no significant difference between the two groups [median increase in plaque volume was 0.00 (-30.00, 40.00) mm3 in the statin group and 30.00 (10.00, 70.00) mm3 in the non-statin group, P>0.05]. CONCLUSION: The VPQ technology of 3DUS can be used to evaluate carotid atherosclerotic plaques. Patients with low GSM (GSM < 40) have more severe vascular stenosis and higher normalized wall index. VPQ technology can also be used to observe the effect of statins on carotid plaque, the GSM of plaques increase in patients who are taking moderate-intensity statin treatment for two years.


Subject(s)
Carotid Stenosis , Hydroxymethylglutaryl-CoA Reductase Inhibitors , Plaque, Atherosclerotic , Aged , Carotid Stenosis/diagnostic imaging , Constriction, Pathologic , Female , Humans , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Male , Middle Aged , Plaque, Atherosclerotic/diagnostic imaging , Plaque, Atherosclerotic/drug therapy , Technology , Ultrasonography
19.
Hand (N Y) ; : 15589447221127334, 2022 Oct 11.
Article in English | MEDLINE | ID: mdl-36218028

ABSTRACT

BACKGROUND: The use of ultrasound in the diagnosis of cubital tunnel syndrome (CuTS) is an attractive alternative to electrodiagnostic (EDX) studies, but its utility is binary with poor severity correlation. We hypothesize that increasing ulnar nerve cross-sectional area (CSA) and power Doppler measurement of intraneural vascularity may predict the extent of disease. METHODS: We identified 20 elbows from patients with a history of CuTS and 20 elbows in 10 asymptomatic controls. Electrodiagnosis was performed for symptomatic patients. Gray-scale ultrasound and power Doppler ultrasound were performed to measure CSA and intraneural vascularity in all participants. Functional measures, Boston Carpal Tunnel Questionnaire (BCTQ), and Patient-Reported Outcomes Measurement Information System surveys were also completed. RESULTS: A strong positive correlation was found between CSA and motor nerve conduction velocity (MNCV) decrease between elbow and forearm, which increased when BCTQ >2 was used as a screening criterion. Increased CSA also demonstrated a high positive predictive value (PPV) in predicting MNCV changes, but poor ability to predict axonal loss. In contrast, power Doppler ultrasound demonstrated 100% PPV and 94% negative predictive value (NPV) in predicting severe CuTS (defined as compound motor action potential [CMAP] amplitude <6 mV and electromyography [EMG] findings). CONCLUSIONS: Cross-sectional area is a sensitive method for identifying changes in MNCV and amplitude but does not stratify disease severity, as defined by diminished CMAP amplitude and/or evidence of denervation on EMG. The presence of increased intraneural vascularity is relatively sensitive but highly specific for axonal loss. The combination of nerve CSA, BCTQ screening, and power Doppler ultrasound may provide an alternative means for CuTS assessment.

20.
Clin Hemorheol Microcirc ; 82(4): 295-301, 2022.
Article in English | MEDLINE | ID: mdl-36093689

ABSTRACT

BACKGROUND: The early detection of infected hydronephrosis is critical before lithotripsy. A feasible and noninvasive diagnostic method is of considerable clinical attention. OBJECTIVES: This retrospective study was performed to find some quantitative evaluation parameters of B-mode Gray-scale ultrasound histogram analysis that might assist the early diagnosis of infected hydronephrosis and test their diagnostic efficacy. MATERIALS AND METHODS: The ultrasound images and clinical data of 245 patients with hydronephrosis were retrospectively analyzed. Image J software was applied to obtain the gray-scale maps and the analysis results of the signal strength. The difference in the data between the infected and non-infected groups and the diagnostic value of the parameters were calculated. RESULTS: In this retrospective study, 70 patients with infected hydronephrosis and 175 patients with non-infected hydronephrosis were enrolled. The echogenicity of internal effusion and the echogenicity ratio of infected cases were significantly higher than those of non-infected cases (p < 0.05). The cutoff values were 23.82 (AUC = 0.859) of echogenicity of internal effusion, while 0.27 (AUC = 0.832) of echogenicity ratio. CONCLUSION: The quantitative evaluation of gray-scale ultrasound histogram is an objective and reliable method in differentiating infected from non-infected hydronephrosis.


Subject(s)
Hydronephrosis , Software , Humans , Retrospective Studies , Diagnosis, Differential , Ultrasonography/methods , Hydronephrosis/diagnostic imaging
SELECTION OF CITATIONS
SEARCH DETAIL
...