Carotid ultrasound requires skilled operators due to small vessel dimensions and high anatomical variability, exacerbating sonographer shortages and diagnostic inconsistencies. Prior automation attempts, including rule-based approaches with manual heuristics and reinforcement learning trained in simulated environments, demonstrate limited generalizability and fail to complete real-world clinical workflows. Here, we present UltraBot, a fully learning-based autonomous carotid ultrasound robot, achieving human-expert-level performance through four innovations: (1) A unified imitation learning framework for acquiring anatomical knowledge and scanning operational skills; (2) A large-scale expert demonstration dataset (247,000 samples, 100 x scale-up), enabling embodied foundation models with strong generalization; (3) A comprehensive scanning protocol ensuring full anatomical coverage for biometric measurement and plaque screening; (4) The clinical-oriented validation showing over 90% success rates, expert-level accuracy, up to 5.5 x higher reproducibility across diverse unseen populations. Overall, we show that large-scale deep learning offers a promising pathway toward autonomous, high-precision ultrasonography in clinical practice.

Although platelet-rich plasma-derived exosomes (PRP-Exos) hold significant repair potential, their efficacy in treating rotator cuff tear (RCT) remains unknown. In light of the potential for clinical translation of fibrin gel and PRP-Exos, we evaluated their combined impact on RCT healing and explored suitable gel implantation techniques. In vitro experiments demonstrated that PRP-Exos effectively enhanced key phenotypes changes in tendon stem/progenitor cells. Multi-modality imaging, including conventional ultrasound, shear wave elastography ultrasound, and micro-computed tomography, and histopathological assessments were performed to collectively evaluate the regenerative effects on RCT. The regenerated tendons exhibited a well-ordered structure, while bone and cartilage regeneration were significantly improved. PRP-Exos participated in the healing process of RCT. In-situ gelation of fibrin gel-encapsulated PRP-Exos at the bone-tendon interface during surgery proved to be a feasible gel implantation method that benefits the healing outcome. Comprehensive multi-modality postoperative evaluations were necessary, providing a reliable foundation for post-injury repair.

Abstract Background and purpose Effective evaluation of rotator cuff tear residual tendon quality is the key to surgical repair. However, until now, the evaluation of rotator cuff tissue by ultrasonic shear wave elasticity (SWE) has been controversial. This prospective study analyzed the association between preoperative SWE and arthroscopic residual tendon quality scores. Methods The shear wave velocity (SWV) of the deltoid muscle, the supraspinatus tendon, and the supraspinatus muscle were measured in full-thickness rotator cuff tear patients. Tendon quality was scored according to tear size, tendon margin, tendon thickness, and footprint coverage during arthroscopy. The arthroscopic scores were used as the gold standard, and the SWV ratio of tendon and muscle (supraspinatus tendon/deltoid and supraspinatus muscle/deltoid) were calculated and correlated with the arthroscopic scores. Result Eighty-nine patients (129 shoulders) were enrolled, including 89 operation shoulders and 40 control shoulders. In the group of operation shoulders, both the SWV ratios of tendon (SWV-RT) and the SWV ratio of muscle (SWV-RM) were negatively correlated with arthroscopic scores (The correlation coefficient (R) ranged from -0.722 to -0.884 and -0.569 to -0.689). The SWV-RT and SWV-RM of the operation shoulders were significantly lower than that of the control shoulders (p < 0.05). Conclusion SWE could be used to predict the quality of the residual tendon before the rotator cuff repair. SWV of the supraspinatus tendon and muscle was a useful parameter to predict the quality of the residual tendon. Critical relevance statement Measuring the shear wave velocity of the supraspinatus tendon and muscle with SWE is useful for predicting the quality of the residual tendon which is one of the key factors for a successful rotator cuff repair. Key points • Evaluating the quality of the residual tendon is important before surgery. • Elasticity measurements were negatively correlated with the arthroscopic score. • SWE is useful for predicting the quality of the residual tendon. Graphical Abstract

Cell therapy based on mesenchymal stem cells (MSCs) alleviate muscle atrophy caused by diabetes and aging; however, the impact of human umbilical cord mesenchymal stem cells on muscle atrophy following nerve injury and the underlying mechanisms remain unclear. In this study, we evaluated the therapeutic efficacy of human umbilical cord MSCs (hucMSCs) and hucMSC-derived exosomes (hucMSC-EXOs) for muscle atrophy following nerve injury and identified the underlying molecular mechanisms. Sciatic nerve crush injury in rats and the induction of myotubes in L6 cells were used to determine the ameliorating effect of hucMSCs and hucMSC-EXOs on muscle atrophy. Q-PCR and Western blot analyses were used to measure the expression of muscle-specific ubiquitin ligases Fbxo32 (Atrogin1, MAFbx) and Trim63 (MuRF-1). Dual-luciferase reporter gene experiments were conducted to validate the direct binding of miRNAs to their target genes. Local injection of hucMSCs and hucMSC-EXOs mitigated atrophy in the rat gastrocnemius muscle following sciatic nerve crush injury. In vitro, hucMSC-EXOs alleviated atrophy in L6 myotubes. Mechanistic analysis indicated the upregulation of miR-23b-3p levels in L6 myotubes following hucMSC-EXOs treatment. MiR-23b-3p significantly inhibited the expression of its target genes, Fbxo32 and Trim63, and suppressed myotube atrophy. Notably, an miR-23b-3p inhibitor reversed the inhibitory effect of miR-23b-3p on myotube atrophy in vitro. These results suggest that hucMSCs and their exosomes alleviate muscle atrophy following nerve injury. MiR-23b-3p in exosomes secreted by hucMSCs contributes to this mechanism by inhibiting the muscle-specific ubiquitination ligases Fbxo32 and Trim63.

Objective To investigate the effects of platelet-rich plasma-derived exosomes (PRP-Exos) on the proliferation and migration of tendon stem/progenitor cell (TSPC).Methods PRP-Exos were extracted through the combination of polymer-based precipitation and ultracentrifugation.The morphology,concentration,and particle size of PRP-Exos were identified by transmission electron microscopy and nanoparticle tracking analysis.The expression levels of surface marker proteins on PRP-Exos and platelet membrane glycoproteins were determined by Western blot analysis.Rat TSPC was extracted and cultured,and the expression of surface marker molecules on TSPC was detected using flow cytometry and immunofluorescence staining.The proliferation of TSPC influenced by PRP-Exos was evaluated using CCK-8 assay and EdU assay.The effect of PRP-Exos on the migration of TSPC was evaluated by cell scratch assay and Transwell assay.Results The extracted PRP-Exos exhibit typical saucer-like structures,with a concentration of 4.9×1011 particles/mL,an average particle size of (132.2±56.8) nm,and surface expression of CD9,CD63 and CD41.The extracted TSPC expressed the CD44 protein.PRP-Exos can be taken up by TSPC,and after co-cultured for 48 h,concentrations of 50 and 100 μg/mL of PRP-Exos significantly promoted the proliferation of TSPC (both P<0.001),with no statistical difference between the two concentrations (P=0.283).Additionally,after co-cultured for 24 h,50 μg/mL of PRP-Exos significantly promoted the migration of TSPC (P<0.001).Conclusion Under in vitro culture conditions,PRP-Exos significantly promote the proliferation and migration of rat TSPC.

Peripheral nerve injury (PNI) is prevalent and has a high disability rate in clinical settings. Current therapeutic methods have not achieved satisfactory efficacy, underscoring the need for novel approaches to nerve restoration that remain an active area of research in neuroscience and regenerative medicine. In this study, we isolated platelet-rich plasma-derived exosomes (PRP-exos) and found that they can significantly enhance the proliferation, migration, and secretion of trophic factors by Schwann cells (SCs). Additionally, there were marked changes in transcriptional and expression profiles of SCs, particularly via the up-regulation of genes related to biological functions involved in nerve regeneration and repair. In the rat model of sciatic nerve crush injury, ultrasound-targeted microbubble destruction (UTMD) enhanced the efficiency of PRP-exos delivery to the injury site. This approach ensured a high concentration of PRP-exos in the injured nerve and improved the therapeutic outcomes. In conclusion, PRP-exos may promote nerve regeneration and repair, and UTMD may increase the effectiveness of targeted PRP-exos delivery to the injured nerve and enhance the therapeutic effect.

In this study, ultrasound (US) contrast arthrography and subacromial-subdeltoid bursography with the contrast agent of SonoVue were performed to evaluate their value for detecting and differentiating the rotator cuff tear (RCT) subtypes in patients with the uncertain RCT. A total of 102 patients with the clinically suspected RCTs in the orthopedic clinic were prospectively recruited and underwent conventional high-frequency US for the category of undoubted full-thickness RCT, uncertain RCT, and intact rotator cuff. Among these patients, the patients with uncertain RCT underwent the subsequent US contrast arthrography and subacromial-subdeltoid bursography. The arthroscopic findings were used as the gold standard in this study. After the conventional US screening, 62 patients with uncertain RCT underwent the subsequent US contrast arthrography and subacromial-subdeltoid bursography. All the US contrast arthrography and subacromial-subdeltoid bursography were successfully performed and no severe side effects were observed in all the patients. For full-thickness tears, the sensitivity and specificity of the combined US contrast arthrography and subacromial-subdeltoid bursography were 94.7 • This is the first study by injection of the US contrast agent SonoVue into the shoulder joint cavity and subacromial-subdeltoid bursa for the detection and differentiation of the RCT subtypes among the people with the uncertain RCT by conventional US screening. • The SonoVue was injected into the glenohumeral joint cavity under US guidance to differentiate the full-thickness RCTs from partial-thickness RCTs. • Combined US contrast arthrography and subacromial-subdeltoid bursography are useful for detecting the RCT subtypes in patients with the uncertain RCTs.

Peripheral nerve injury is prevalent and has a high disability rate in clinical settings. Current therapeutic methods have not achieved satisfactory efficacy, underscoring the need for novel approaches to nerve restoration that remains an active area of research in neuroscience and regenerative medicine. In this study, we isolated platelet-rich plasma-derived exosomes (PRP-exos) and found that they can significantly enhance the proliferation, migration, and secretion of trophic factors by Schwann cells (SCs). In addition, there were marked changes in transcriptional and expression profiles of SCs, particularly via the upregulation of genes related to biological functions involved in nerve regeneration and repair. In the rat model of sciatic nerve crush injury, ultrasound-targeted microbubble destruction (UTMD) enhanced the efficiency of PRP-exos delivery to the injury site. This approach ensured a high concentration of PRP-exos in the injured nerve and improved the therapeutic outcomes. In conclusion, PRP-exos may promote nerve regeneration and repair, and UTMD may increase the effectiveness of targeted PRP-exos delivery to the injured nerve and enhance the therapeutic effect.

Objective:To explore the feasibility and clinical effect of ultrasound-guided injection via the rotator interval into the glenohumeral joint and subdeltoid bursa for the treatment of frozen shoulder.Methods:From March 2020 to March 2021 at our hospital, 65 patients diagnosed with frozen shoulder were treated by ultrasound-guided injection via the rotator interval into the glenohumeral joint and subdeltoid bursa. Ultrasound examination was performed before the treatment and the shortest distance from the biceps longhead tendon to the skin and the thickness of the coracohumeral ligament were measured. The visual analogue scale (VAS) scores, Constant scores, and University of California, Los Angeles (UCLA) scores before the treatment and at 1 week, 1 month, and 3 months after the treatment were recorded to evaluate the clinical effect.Results:The average shortest distance from the biceps longhead tendon to the skin was (11.81±2.52) mm, and the average thickness of the coracohumeral ligament was (2.69±0.42) mm. Compared to pretreatment value, VAS scores decreased significantly at 1 week, 1 month, and 3 months after treatment (P＜0.008). The Constant and UCLA scores at 1 month and 3 months after treatment were significantly increased compared with those before the treatment (P＜0.016); compared with the values at 1 month after treatment, the Constant and UCLA scores were not significantly improved at 3 months after treatment (P＞0.016). The degree of pain, activities of daily living, range of motion of the shoulder joint, and muscle strength in the Constant scale were significantly improved at 1 month and 3 months after treatment compared with those before treatment (P＜0.016); compared with those at 1 month after treatment, there was no further improvement in the degree of pain, activities of daily living, range of motion of the shoulder joint, and muscle strength at 3 months after treatment (P＞0.016).Conclusion:Ultrasound-guided injection via the rotator interval into the glenohumeral joint and subdeltoid bursa could be a feasible method for frozen shoulder.

Background Developing biocompatible nerve conduits that accelerate peripheral nerve regeneration, lengthening and functional recovery remains a challenge. The combined application of nerve microtissues and platelet-rich plasma (PRP) provides abundant Schwann cells (SCs) and various natural growth factors and can compensate for the deficiency of SCs in the nerve bridge, as well as the limitations of applying a single type of growth factor. Multimodal ultrasound evaluation can provide additional information on the stiffness and microvascular flow perfusion of the tissue. This study was designed to investigate the effectiveness of a novel tissue-engineered nerve graft composed of an autogenous vein, nerve microtissues and PRP in reconstructing a 12-mm tibial nerve defect and to explore the value of multimodal ultrasound techniques in evaluating the prognosis of nerve repair. Methods In vitro, nerve microtissue activity was first investigated, and the effects on SC proliferation, migration, factor secretion, and axonal regeneration of dorsal root ganglia (DRG) were evaluated by coculture with nerve microtissues and PRP. In vivo, seventy-five rabbits were equally and randomly divided into Hollow, PRP, Micro-T (Microtissues), Micro-T + PRP and Autograft groups. By analysing the neurological function, electrophysiological recovery, and the comparative results of multimodal ultrasound and histological evaluation, we investigated the effect of these new nerve grafts in repairing tibial nerve defects. Results Our results showed that the combined application of nerve microtissues and PRP could significantly promote the proliferation, secretion and migration of SCs and the regeneration of axons in the early stage. The Micro-T + PRP group and Autograft groups exhibited the best nerve repair 12 weeks postoperatively. In addition, the changes in target tissue stiffness and microvascular perfusion on multimodal ultrasound (shear wave elastography; contrast-enhanced ultrasonography; Angio PlaneWave UltrasenSitive, AngioPLUS) were significantly correlated with the histological results, such as collagen area percentage and VEGF expression, respectively. Conclusion Our novel tissue-engineered nerve graft shows excellent efficacy in repairing 12-mm defects of the tibial nerve in rabbits. Moreover, multimodal ultrasound may provide a clinical reference for prognosis by quantitatively evaluating the stiffness and microvescular flow of nerve grafts and targeted muscles.

Background: Developing biocompatible nerve conduits that accelerate peripheral nerve regeneration, lengthening and functional recovery remains a challenge. The combined application of nerve microtissues and platelet-rich plasma (PRP) provides abundant Schwann cells (SCs) and various natural growth factors and can compensate for the deficiency of SCs in the nerve bridge, as well as the limitations of applying a single type of growth factor. Multimodal ultrasound evaluation can provide additional information on the stiffness and microvascular flow perfusion of the tissue. This study was designed to investigate the effectiveness of a novel tissue-engineered nerve graft composed of an autogenous vein, nerve microtissues and PRP in reconstructing a 12-mm tibial nerve defect and to explore the value of multimodal ultrasound techniques in evaluating the prognosis of nerve repair. Methods: In vitro, nerve microtissue activity was first investigated, and the effects on SC proliferation, migration, factor secretion, and axonal regeneration of dorsal root ganglia (DRG) were evaluated by coculture with nerve microtissues and PRP. In vivo, seventy-five rabbits were equally and randomly divided into Hollow, PRP, Micro-T (Microtissues), Micro-T+PRP and Autograft groups. By analysing the neurological function, electrophysiological recovery, and the comparative results of multimodal ultrasound and histological evaluation, we investigated the effect of these new nerve grafts in repairing tibial nerve defects. Results: Our results showed that the combined application of nerve microtissues and PRP could significantly promote the proliferation, secretion and migration of SCs and the regeneration of axons in the early stage. The Micro-T+PRP group and Autograft groups exhibited the best nerve repair 12 weeks postoperatively. In addition, the changes in target tissue stiffness and microvascular perfusion on multimodal ultrasound (shear wave elastography; contrast-enhanced ultrasonography; Angio PlaneWave UltrasenSitive, AngioPLUS) were significantly correlated with the histological results, such as collagen area percentage and VEGF expression, respectively. Conclusion: Our novel tissue-engineered nerve graft shows excellent efficacy in repairing 12-mm defects of the tibial nerve in rabbits. Moreover, multimodal ultrasound may provide a clinical reference for prognosis by quantitatively evaluating the stiffness and microvescular flow of nerve grafts and targeted muscles.

Objective To explore the value of conventional ultrasound combined with shear-wave elastography in the quantitative evaluation of sciatic nerve crush injury in rabbit models. Methods Forty healthy male New Zealand white rabbits were randomly divided into four groups (n=10 in each group):three crush injury (CI) groups (2,4,and 8 weeks after crush) and control group (without injury). The thickness and stiffness of the crushed sciatic nerves and denervated triceps surae muscles were measured at different time points and compared with histopathologic parameters. Inter-reader variability was assessed with intraclass correlation coefficients. Results Compared with the control group,the inner diameters of the sciatic nerves significantly increased in the 2-week CI group [(1.65±0.34) mm vs. (0.97±0.15) mm,P=0.00] but recovered to the nearly normal level in the 8-week CI group [(1.12±0.18) mm vs. (0.97±0.15) mm,P=0.06];however,compared with control group [(8.75±1.02)kPa],the elastic modulus of the nerves increased significantly in all the CI groups [2-week:(14.77±2.53) kPa;4-week:(19.12±3.46) kPa;and 8-week:(28.39±5.26) kPa;all P=0.00];pathologically,massive hyperplasia of collagen fibers were found in the nerve tissues. The thickness of denervated triceps surae muscle decreased gradually,and the elastic modulus decreased 2 weeks after injury but increased gradually in the following 6 weeks;pathologically,massive hyperplasia of collagen fibers and adipocytes infiltration were visible,along with decreased muscle wet-weight ratio and muscle fiber cross-sectional area. The inter-reader agreements were good. Conclusion Conventional ultrasound combined with shear-wave elastography is feasible for the quantitative evaluation of the morphological and mechanical properties of crushed nerves and denervated muscles.

Objective To explore the value of contrast-enhanced ultrasound(CEUS)in the detection of peripheral nerve crush injury.Methods Thirty New Zealand white rabbits were randomly divided into normal control group and sciatic nerve crush injury group(which included 3-day,2-week,4-week,and 8-week groups after operation).The morphological structure and blood perfusion of the injured sciatic nerves were detected by high-frequency ultrasound,power Doppler ultrasound(PDUS),CEUS,and histopathology.Results Conventional ultrasound revealed that the internal diameter of nerves showed no significant difference between the 8-week group and the control group [(1.14±0.15)mm vs.(0.92±0.11)mm;t=4.72,P=0.86].Analysis of nerve blood perfusion showed that PDUS had a high sensitivity in displaying fine blood flow signal inside the injured nerve in the acute stage of inflammation(3-day group)but not good enough in the 4-and 8-week groups.CEUS could clearly show the microcirculation perfusion in the 3-day,2-week,4-week,and 8-week groups,and analyses of the area under the curve,the peak time,and the peak intensity showed that the nerve blood perfusion increased significantly 3 days after operation and then decreased gradually.Histopathological examination showed that the median cumulative OD value was 12 035.6(10 566.3,14 805.8)8 weeks after operation,which was still significantly lower than that 18 784.8(15 904.5,21 103.5)in the normal control group(H=6.10, P=0.0003).Conclusions Conventional high-frequency ultrasound and PDUS can not adequately evaluate the microcirculation perfusion in different periods after nerve injury.CEUS can quantitatively evaluate the microvascular perfusion of injured nerve at any period and provide more information for indirect evaluation of nerve regeneration.

超声引导下颈神经根阻滞可准确、安全、有效、实时地引导穿刺针注射药物到颈神经根周围,有效避免血管和神经损伤,减少并发症的发生,越来越受到临床的关注.本文对超声引导下颈神经根阻滞的研究进展进行综述,阐述超声在该领域的应用价值.

目的 探讨超声引导下注药治疗腹股沟疝术后疼痛并发症应用价值的初步评估.方法 回顾性分析2018年6月至2019年8月,解放军总医院第一医学中心超声诊断科治疗15例因腹股沟疝术后不明原因且无法缓解疼痛的患者,行超声引导下对髂腹下神经、髂腹股沟神经及生殖股神经生殖支周围软组织区域进行注药治疗,应用疼痛视觉模拟评分(VAS)来分别评估术前、术后24 h、48 h、2周、4周的疼痛缓解情况.结果 在超声引导下进行髂腹下神经、髂腹股沟神经及生殖股神经生殖支周围软组织区域注药治疗后,患者短期疼痛明显缓解,24 h尤为显著,术前、术后24 h、48 h、2周、4周的VAS评分比较分别为(3.5±0.8)、(0.7±0.8)、(1.5±1.0)、(2.5±0.8)、(2.7±0.8)分,治疗前与治疗后各时间点比较,差异均有统计学意义(P<0.05),但治疗术后2周与4周的VAS评分比较,差异无统计学意义(P>0.05).结论 超声引导下注药治疗腹股沟疝术后疼痛,短期临床效果显著,且具有实时引导、安全、无辐射等优点,故可作为临床缓解腹股沟疝术后疼痛的一种有效的治疗方法.

Ultrasound-guided platelet-rich plasma (PRP) injection is able to make up for the limitations of applying a single growth factor. The goal of this study was to investigate the effects of serial ultrasound-guided PRP injections of the appropriate concentration on the treatment of sciatic nerve crush injury, and explore the value of multimodality ultrasound techniques in evaluating the prognosis of crushed peripheral nerve. In vitro, optimal concentration of PRP (from 150%, 250%, 450%, and 650%) was screened due for its maximal effect on proliferation and neurotrophic function of Schwann cells (SCs). In vivo, ninety rabbits were equally and randomly divided into normal control, model, PRP-2.5×, PRP-4.5×, and PRP-6.5× groups. The neurological function and electrophysiological recovery evaluation, and the comparison of the multimodality ultrasound evaluation with the histological results of sciatic nerve crush injury were performed to investigate the regenerative effects of PRP at different concentrations on the sciatic nerve crush injury. Our results showed that the PRP with a 4.5-fold concentration of whole blood platelets could significantly stimulate the proliferation and secretion of SCs and nerve repair. The changes in stiffness and blood perfusion were positively correlated with the collagen area percentage and VEGF expression in the injured nerve, respectively. Thus, serial ultrasound-guided PRP injections at an appropriate concentration accelerates the recovery of axonal function. Multimodality ultrasound techniques provide a clinical reference for prognosis by allowing the stiffness and microcirculation perfusion of crush-injured peripheral nerves to be quantitatively evaluated.

目的 探讨剪切波弹性成像(SWE)定量评估外周神经硬度的应用价值.资料与方法 应用SWE对健康青年男女各30例进行检测,分别于腕关节自然位、最大掌屈位、最大背伸位及膝关节自然位、被动屈曲90°下纵切和横切以检测正中神经和坐骨神经的剪切波弹性测值.结果 同一关节体位下,正中神经及坐骨神经纵切、横切的弹性测值差异均有统计学意义(P<0.05),且纵切测值较高.腕关节各体位下,正中神经纵切弹性测值差异有统计学意义(P<0.05),最大背伸位测值最高;横切自然位和最大掌屈位分别与最大背伸位的测值差异有统计学意义(P<0.05),自然位与最大掌屈位测值差异无统计学意义(P>0.05).膝关节各体位下,坐骨神经纵切弹性测值差异有统计学意义(P<0.05),横切弹性测值差异无统计学意义(P>0.05).结论 正中神经、坐骨神经剪切波弹性测值的大小与超声纵切或横切、关节体位变化有关.