Ultrasound in Medicine and Biology最新文献

{"title":"Prostate Cancer Detection on Micro-Ultrasound Raw Data Using a Deep Learning Neural Network.","authors":"Ahmed El Kaffas, Thodsawit Tiyarattanachai, Mirabela Rusu, Brian Wodlinger, Richard E Fan, Michael Liss, Rebecca Rakow-Penner, Geoffrey A Sonn","doi":"10.1016/j.ultrasmedbio.2026.04.002","DOIUrl":"https://doi.org/10.1016/j.ultrasmedbio.2026.04.002","url":null,"abstract":"<p><strong>Background: </strong>Micro-ultrasound (micro-US) is a clinically available novel high-resolution imaging technology for guiding prostate biopsies. However, clinical image interpretation during live biopsies remains a challenge.</p><p><strong>Purpose: </strong>To develop a convolutional neural network (CNN) to classify prostate tissues as benign versus clinically significant prostate cancer (csPCa) from the power spectrums (PS) derived from raw micro-US, with the eventual goal of developing a tool for automating interpretation during image-guided biopsies.</p><p><strong>Methods: </strong>Retrospective Micro-US data were obtained from 491 men (mean age 62 y, SD 8) undergoing prostate biopsy across 5 sites between 2013 and 2016; associated raw data and prostate-specific antigen (PSA) were obtained for each targeted biopsy location and used to obtain spatially mapped PSs. The dataset was split at a patient-level into a train/validation (80%) and a set-aside test set (20%). This includes up to 12 image-frames at distinct prostate locations (total of 6530 single image-frames), each with a corresponding biopsy. No specific prostate tissue segmentation was carried out. A custom CNN named PSNet was developed to classify benign from csPCa in non-segmented regions of micro-US data, and its performance was compared to traditional CNNs trained on associated conventional B-Mode images. Biopsy histopathology served as the clinical standard labels. The area under the receiver operator curve (ROC-AUC) was used to evaluate all models; sensitivity, specificity, precision and the F1 score were also computed; 95% confidence interval is shown in parenthesis.</p><p><strong>Results: </strong>For frame-level performance, PSNet without PSA achieved an ROC-AUC of 82% (0.77, 0.85), a sensitivity of 0.73 (0.66, 0.80) and a specificity of 0.74 (0.71, 0.77) for classifying benign versus csPCa. After inclusion of PSA, the ROC-AUC increased to 85% (0.83, 0.88), with a sensitivity of 0.72 (0.65, 0.79) and a specificity of 0.82 (0.80, 0.84). For patient-level performance, which was obtained by aggregating image-level predictions, the models without and with PSA achieved patient-level ROC-AUCs of 85% (0.77, 0.92) and 91% (0.85, 0.97), sensitivities of 0.74 (0.70, 0.79) and 0.70 (0.65, 0.75) and specificities of 0.88 (0.76, 0.84) and 0.99 (0.98, 1.00), respectively.</p><p><strong>Conclusion: </strong>In this pilot development study, we suggest that deep learning can capture unique tissue acoustic properties in raw micro-US data to help identify prostate cancer, without the need for segmentation of the prostate gland, and that the diagnostic value of these tissue properties can be augmented by PSA measurements to increase specificity. Our approach may be further leveraged to guide targeted prostate biopsy.</p>","PeriodicalId":49399,"journal":{"name":"Ultrasound in Medicine and Biology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2026-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147857527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-Frequency Ultrasonography for Ex Vivo Periodontal Tissue Measurement: Accuracy and Reproducibility Compared to Cone Beam Computed Tomography.","authors":"Laurent Estrade, Baptiste Ait Slimane, Alexis Delpierre, Victor Rimbaud, Frédéric Denis, Gaël Y Rochefort, Matthieu Renaud","doi":"10.1016/j.ultrasmedbio.2026.02.013","DOIUrl":"https://doi.org/10.1016/j.ultrasmedbio.2026.02.013","url":null,"abstract":"<p><strong>Objective: </strong>The aim of this study was to assess the accuracy and reproducibility of periodontal tissue measurements obtained through ultrasonographic imaging, by comparing them ex vivo to reference measurements acquired via cone beam computed tomography (CBCT).</p><p><strong>Methods: </strong>A total of 12 hemi-jaws were included in the study. CBCT acquisition was realised, and then ultrasound measurements of periodontal structures were performed. Ultrasound imaging was performed with a linear array 20 MHz probe (field of view 14.1 × 6.4 mm; penetration depth ≈ 4.9 mm; axial/lateral resolution 80/120 µm). The ultrasound images were analysed using ImageJ software. Reference points were made allowing the measurement of the different tissues. A Kolmogorov-Smirnov test and Lin's concordance test were performed for each of the samples due to the size of their population (>50).</p><p><strong>Results: </strong>A total of 348 manual probing measurements were performed. Lin's concordance correlation coefficients were: gingival thickness: 0.479 (95% CI [0.393-0.558]); distance from the alveolar crest to the CEJ: 0.872 (95% CI [0.842-0.897]); distance from the alveolar crest to the gingival margin: 0.794 (95% CI [0.749-0.832]); alveolar bone thickness: -0.0165 (95% CI [-0.0512 to 0.0183]).</p><p><strong>Conclusion: </strong>High-frequency ultrasonography demonstrates high accuracy and reproducibility for measuring periodontal structures ex vivo, particularly for the distance from the alveolar crest to the CEJ, but further clinical studies are needed to validate its use in vivo.</p><p><strong>Clinical relevance: </strong>This non-ionising technique offers a safe alternative to CBCT for periodontal assessment, with potential to enhance early diagnosis and monitoring in clinical practice while minimising radiation exposure.</p>","PeriodicalId":49399,"journal":{"name":"Ultrasound in Medicine and Biology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2026-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147857573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Super-Resolution Ultrasound Radiomics Nomogram for Preoperative Prediction of Lateral Lymph Node Metastasis in Papillary Thyroid Carcinoma: A Development and Validation Study.","authors":"Lele Song, Wenwen Fan, Ruining Wang, Qian Zhang, Yufang Zhao, Yanjing Zhang, Yun Liu, Guolin Yin, Xiaohui Yan, Jiayi Jin, Ping Liang, Liping Liu","doi":"10.1016/j.ultrasmedbio.2026.01.015","DOIUrl":"https://doi.org/10.1016/j.ultrasmedbio.2026.01.015","url":null,"abstract":"<p><strong>Objective: </strong>Super-resolution ultrasound (SRUS) enables the visualization and quantification of nodal microvasculature; however, the existing quantitative parameters are relatively simplistic. This study aimed to assess SRUS-based ultrasomics for diagnosing metastatic lateral cervical lymph nodes (LNs) in papillary thyroid carcinoma (PTC).</p><p><strong>Methods: </strong>A total of 171 suspicious lateral cervical LNs from 148 patients with PTC were retrospective included. All LNs underwent B-mode, contrast-enhanced ultrasound (CEUS), and SRUS. Using surgical pathology as the gold standard, radiomics models were constructed by extracting high-throughput features from SRUS images, resulting in three models: the B-mode + CEUS, B-mode + SRUS, and B-mode + CEUS + SRUS models. The optimal radiomics model from the training set was combined with clinical risk factors to construct a nomogram. Discriminatory ability was assessed using the area under the receiver operating characteristic curve (AUC). Calibration curves and decision curve analysis (DCA) were used to evaluate the nomogram's calibration and clinical utility. Finally, the diagnostic performance of the nomogram was compared with that of fine-needle aspiration cytology (FNAC) and thyroglobulin (FNA-Tg) measurements.</p><p><strong>Results: </strong>Among the 171 LNs, 104 were malignant and 67 were benign. The B-mode + CEUS + SRUS model performed best among three radiomics models (validation set AUC = 0.892). The nomogram demonstrated further improved diagnostic performance (validation set AUC = 0.960), with accuracy significantly superior to that of FNAC (p = 0.027) and an AUC comparable to that of FNA-Tg (p = 0.754). Calibration curves and DCA indicated good calibration and clinical benefit.</p><p><strong>Conclusion: </strong>The SRUS-based radiomics nomogram enables noninvasive, accurate prediction of lateral cervical LN metastasis in PTC, potentially reducing unnecessary biopsies and showing significant clinical value.</p>","PeriodicalId":49399,"journal":{"name":"Ultrasound in Medicine and Biology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2026-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147844907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-invasive Ultrasound Liver Ablation Using Histotripsy: A Feasibility Study in Ex Vivo Porcine Liver and a Chronic Study in Rodent Models In Vivo.","authors":"Yufan Wei, Shuaiqi Li, Qilong Wang, Zhicheng Bai, Boya Zhang, Hongye Zheng, Yu Li, Na Li, Ziheng Xu, Jiaxiong Li, Daoxiang Peng, Li Zhu, Xiru Li","doi":"10.1016/j.ultrasmedbio.2026.03.001","DOIUrl":"https://doi.org/10.1016/j.ultrasmedbio.2026.03.001","url":null,"abstract":"<p><strong>Objective: </strong>This study aimed to investigate the feasibility of histotripsy ablating the liver ex vivo, as well as characterize the acute and chronic impact of histotripsy in vivo.</p><p><strong>Methods: </strong>A home-made histotripsy system was used to treat liver tissues. A 42-element near-half spherical focusing transducer array was designed with a 13.5 cm focal length, 24 cm aperture and 710 kHz frequency, with an f-number of 0.2083. Initial parameter exploration was measured. The type of histotripsy used lies between the intrinsic threshold cavitation and shock-scattering histotripsy with a pulse duration of 1-3 μs, pulse repetition frequency range of 166-250 Hz and pressure of >50 MPa. Acute and chronic observational experiments were utilized in rodent models in vivo to assess the efficacy and safety of histotripsy, with endpoints at 0, 3, 7, 14 and 28 d post-ablation. Ablation was characterized using hematoxylin-eosin staining, with Masson's trichrome staining conducted to visualize the deposition and distribution of collagen fibers, and TdT-mediated dUTP nick-end labeling (TUNEL) assay used to reveal the spatiotemporal evolution of apoptosis. α-SMA and TGF-β expression was detected to track the process of fibrosis activation and regression in vivo. Serum alanine aminotransferase and aspartate aminotransferase were detected to examine liver function.</p><p><strong>Results: </strong>The XC-100 histotripsy system developed by the study was able to achieve complete mechanical ablation of both ex vivo and in vivo liver tissues without inducing thermal damage. Unlike high-intensity focused ultrasound, the liver tissue in the targeted area post-histotripsy demonstrated the ability to repair and regenerate, thereby ensuring safety and reliability.</p><p><strong>Conclusion: </strong>This study provides further evidence for the effectiveness and safety of histotripsy.</p>","PeriodicalId":49399,"journal":{"name":"Ultrasound in Medicine and Biology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2026-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147844869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D Freehand Ultrasound Reconstruction of the Carotid Artery.","authors":"Yimeng Dou, Maxwell J Kiernan, Zhiwei Zhang, Carol Mitchell, Amber Possell, Matthew Lee, Tomy Varghese","doi":"10.1016/j.ultrasmedbio.2026.03.005","DOIUrl":"https://doi.org/10.1016/j.ultrasmedbio.2026.03.005","url":null,"abstract":"<p><strong>Objective: </strong>Sensorless alignment of two-dimensional (2D) freehand ultrasound scans for three-dimensional US (3DUS) reconstruction offers significant advantages due to its ease of use. Prior approaches have used transducers with motion sensors, which are cumbersome and inconvenient in a clinical setting, linear wobblers, or motorized 2D scanning which suffer from a small field of view (FOV) and low volume acquisition rates.</p><p><strong>Method: </strong>Freehand transverse B-mode data loops from 20 human volunteers (10 males, 10 females) were used for 3DUS reconstruction Our two-stream Physics inspired Learning-based Prediction of Pose Information (PLPPI) model explicitly integrates and utilizes speckle decorrelation as an inductive bias (temporal information) along with spatial information for alignment using 2D convolutions. A correlation layer then synergizes spatiotemporal cues for freehand frame alignment. A residual neural network (ResNet) predicted the spatial location of the input frames.</p><p><strong>Results: </strong>PLPPI outperformed baseline deep learning networks (DLN), i.e. 2D CNN, ConvLSTM, and DC²-Net, with a 13% improvement in global pixel reconstruction error, 59.36% improvement in final drift, and 35.74% in final drift rate over the next best DLN, while requiring significantly less Graphics Processing Unit (GPU) memory.</p><p><strong>Conclusion: </strong>Our model has fewer parameters, requiring less GPU memory to train for freehand 3DUS reconstruction along with a major reduction in computation time (106% speedup and 131% reduction in GPU memory usage) compared to baseline DLN.</p>","PeriodicalId":49399,"journal":{"name":"Ultrasound in Medicine and Biology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147844874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Applying SENIAM Guidelines to Shear Wave Elastography: A Novel Approach to Standardizing Transducer Placement for Muscle Imaging.","authors":"Meaghan Hannigan, Ryan Matthews, Sophie Rayner, Rebecca Moyer","doi":"10.1016/j.ultrasmedbio.2026.04.001","DOIUrl":"https://doi.org/10.1016/j.ultrasmedbio.2026.04.001","url":null,"abstract":"<p><strong>Introduction: </strong>Ultrasound shear wave elastography (SWE) is used to assess musculoskeletal tissue properties, but methodological inconsistencies, particularly in probe placement, have limited the generalizability of findings. Therefore, this technical note investigated the use of standardized surface muscle electromyography sensor placement guidelines for ultrasound transducer placement during SWE on lower-limb muscle tissue.</p><p><strong>Methods: </strong>A total of 31 individuals with unilateral symptoms of knee osteoarthritis were recruited from the community. Quadriceps muscle SWE measures were acquired and analyzed across sites with coefficients of variance and image quality maps.</p><p><strong>Results: </strong>All measured muscles demonstrated consistently low intra-trial variability (mean coefficient of variance = 6.6%) and high image quality.</p><p><strong>Conclusion: </strong>The findings suggest that standardization of transducer placement is feasible for SWE, but further investigations across varying muscle groups, clinical populations and research applications are required.</p>","PeriodicalId":49399,"journal":{"name":"Ultrasound in Medicine and Biology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2026-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147822808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Visualizing Periampullary Tumors with Intraductal Ultrasound utilizing an Intracardiac Echocardiography Catheter: A Feasibility Study.","authors":"Mark Ramaekers, Catarina Dinis Fernandes, Xueting Li, Robert-Jan Schipper, Simona Turco, Ignace H J T de Hingh, Joost Nederend, Massimo Mischi, Misha D P Luyer","doi":"10.1016/j.ultrasmedbio.2026.02.022","DOIUrl":"https://doi.org/10.1016/j.ultrasmedbio.2026.02.022","url":null,"abstract":"<p><strong>Objective: </strong>Early detection of pancreatic cancer is crucial for survival, but detecting smalllesions remains challenging. Intraductal Ultrasound (IDUS) using intracardiac echocardiography (ICE) catheters for B-mode and Shear-Wave Elastography (SWE) potentially offers improved visualization and characterization of small tumors. This study assesses the feasibility of IDUS using ICE catheters to detect and visualize periampullary tumors in surgically resected specimens.</p><p><strong>Methods: </strong>In this two-phase ex-vivo feasibility study, 25 pancreatic specimens were included, of which the first 10 were used to establish and standardize the imaging protocol, followed by technical feasibility evaluation in the remaining 15 specimens. Catheters were introduced into the pancreatic duct, common bile duct, or positioned extraductally to enable tumor visualization with B-mode imaging and shear-wave elastography (SWE). Tumor visualization rates, catheter insertion success, SWE measurements in normal and tumor tissue, and image quality were assessed.</p><p><strong>Results: </strong>ICE catheter insertion was successful in 12 of 15 specimens; unsuccessful access was primarily related to large tumor size (>4 cm) or unidentifiable ductal anatomy following surgical resection. However, extraluminal imaging successfully visualized tumors in one of these cases. Median shear-wave speed and elastic modulus for normal pancreatic parenchyma were 1.58 m/s and 7.6 kPa, respectively. SWE measurements in tumor tissue were suboptimal, likely due to ex-vivo tissue variability and catheter strain during repeated use.</p><p><strong>Conclusion: </strong>IDUS with ICE is feasible for qualitative B-mode visualization of periampullary tumors and enables SWE assessment of pancreatic parenchyma in an ex-vivo setting. Reliable elastography of tumor tissue remained challenging, indicating the need for further technical refinement and in-vivo validation.</p>","PeriodicalId":49399,"journal":{"name":"Ultrasound in Medicine and Biology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147822765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Stepwise Diagnostic Strategy Combining a Simplified US-Based Node-RADS with Postvascular Phase Perfluorobutane-CEUS for Indeterminate Cervical Lymph Nodes: A Dual-Center Retrospective Study.","authors":"Naxiang Liu, Liqin Lan, Wenrong Lin, Zhaoming Zhong, Zhougui Wu, Zhongshi Du, Yijie Chen, Lina Tang, Songsong Wu","doi":"10.1016/j.ultrasmedbio.2026.03.015","DOIUrl":"https://doi.org/10.1016/j.ultrasmedbio.2026.03.015","url":null,"abstract":"<p><strong>Objective: </strong>To develop a conventional ultrasound (US)-based Node-reporting and data systems (US-Node-RADS) for cervical lymph nodes (CLNs) and to evaluate whether the subsequent application of postvascular phase perfluorobutane-contrast-enhanced ultrasound (CEUS) can reclassify its indeterminate (Node-RADS 3) category and reduce unnecessary biopsies.</p><p><strong>Methods: </strong>In this dual-center retrospective study, data were analyzed from patients whose imaging had been prospectively acquired under a standardized protocol. A 5-point US-Node-RADS was developed in a training set (n = 356) and validated internally (n = 152) and externally (n = 45). For nodes classified as indeterminate Node-RADS 3, PVP-CEUS was applied: iso-/hyperenhancement prompted downgrading to Node-RADS 2 (follow-up), while no-/hypoenhancement prompted upgrading to Node-RADS 4 (biopsy). Histopathology and follow-up served as the reference standard. Diagnostic performance metrics were statistically evaluated.</p><p><strong>Results: </strong>The US-based Node-RADS showed moderate diagnostic performance (AUC 0.78 in training) but left a substantial proportion (40.2%) of nodes in the indeterminate Node-RADS 3 category. Applying PVP-CEUS to these nodes successfully reclassified them, safely avoiding 14.7% to 40.0% of unnecessary biopsies across the cohorts. This was achieved while maintaining high malignancy identification rates, which increased to 79.3%-100% after reclassification, exceeding the baseline malignancy rates for Node-RADS 3 (training set: 67.8%; internal validation: 69.0%; external validation: 60.0%).</p><p><strong>Conclusion: </strong>Applying PVP-CEUS to Node-RADS 3 nodes effectively resolves diagnostic ambiguity for indeterminate CLNs. This two-step strategy significantly reduces unnecessary biopsy procedures while preserving high sensitivity for malignancy identification, can serve as a potential standardized and actionable pathway to aid preoperative decision-making in appropriately selected patients.</p>","PeriodicalId":49399,"journal":{"name":"Ultrasound in Medicine and Biology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147822778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Clinical Perspective and Review on the Use of the Subharmonic Signal of Ultrasound Contrast Agents for Noninvasive Pressure Estimation.","authors":"Gautam Babu, Lance De Koninck, Samuel G Rayner, Nico de Jong, Robb W Glenny, Michalakis A Averkiou","doi":"10.1016/j.ultrasmedbio.2026.03.027","DOIUrl":"https://doi.org/10.1016/j.ultrasmedbio.2026.03.027","url":null,"abstract":"<p><p>Changes in physiological pressures play a key role in the development and progression of human disease processes. Thus, the assessment of pressures within blood vessels and other bodily compartment is crucial in the diagnosis and management of multiple medical conditions. Presently, techniques for pressure measurement are invasive or have limited accuracy and scope of assessment. Utilizing the subharmonic signal of ultrasound contrast agents offers a promising solution that could address these limitations. After the initial development of this technology in the late nineties, further investigation has brought subharmonic pressure estimation from in vitro exploration to attempts at clinical implementation. However, lack of availability of subharmonic imaging on most clinical scanners, and variability of subharmonic response with different contrast agents have impeded clinical acceptance and widespread use of this modality. This review examines subharmonic imaging and the use of ultrasound contrast agents for estimating physiological pressures, particularly in the heart and portal venous system. A focus is placed on clinically relevant physiologic pressures and their existing measurement approaches, the physics of subharmonic signal generation, in vitro studies demonstrating key findings, and more recent clinical trials. The review also highlights present limitations and future research directions that may help advance clinical translation.</p>","PeriodicalId":49399,"journal":{"name":"Ultrasound in Medicine and Biology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147822409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The feasibility of combining focused ultrasound and copper-cystine biohybrid for diabetic wound healing.","authors":"Anik Karan, Abhirup Samaddar, Prakash Adhikari, Madhumitra Subramanian Karthikesh, Mark A DeCoster, Xinmai Yang","doi":"10.1016/j.ultrasmedbio.2026.03.018","DOIUrl":"https://doi.org/10.1016/j.ultrasmedbio.2026.03.018","url":null,"abstract":"<p><strong>Objective: </strong>Chronic wound healing, particularly in diabetic wounds, remains challenging due to the lack of effective therapeutic procedures. Pharmacological treatments are often limited by physical side effects, while surgical procedures carry a risk of site infections. This study aimed to provide an overall complete therapeutic regimen for faster diabetic wound healing through focused ultrasound (FUS) in conjunction with localized copper-cystine biohybrids.</p><p><strong>Methods: </strong>In the current study, we investigated the feasibility of combining FUS performed at 1 MPa, 2500 cycles, 10% duty cycle, 20 Hz pulse repetition frequency and 15-min treatment durations every alternate day over 14 d with localized copper-cystine biohybrid (copper high aspect ratio structures [CuHARS]) treatment, which is a metal-organic biohybrid capable of promoting angiogenesis and exerting a bactericidal effect on wound healing. Therapeutic efficacy was evaluated in diabetic mice with surgically induced dermal wounds using three treatment groups: combined CuHARS-FUS, CuHARS-only and FUS-only over 7- and 14-d periods.</p><p><strong>Results: </strong>The results showed that CuHARS-FUS treatment for 14 ds achieved complete wound closure, whereas the CuHARS-only, FUS-only and control groups exhibited partial or no healing.</p><p><strong>Conclusion: </strong>The synergistic treatment of CuHARS-FUS supports rapid macrovascular structure formation and proper cellular differentiation, leading to granulation tissue formation by providing a controlled mechanism for tissue remodeling during the entire healing phase of diabetic wound healing, starting from an enhanced angiogenic activity and bactericidal effect via the CuHARS through Cu²⁺ ions-based catalytic decomposition of S-nitrosothiols to nitric oxide and the continuation of endothelial activity through enhanced nitric oxide production due to FUS treatment.</p>","PeriodicalId":49399,"journal":{"name":"Ultrasound in Medicine and Biology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2026-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147787256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}