Study on the Consistency of Angiogenesis in Carotid Plaque Evaluated by Contrast-Enhanced Ultrasound and Superb Microvascular Imaging and Its Correlation With Stroke Occurrence

OBJECTIVES

This study aimed to investigate the value of contrast-enhanced ultrasound (CEUS) and superb microvascular imaging (SMI) in evaluating angiogenesis in carotid artery plaques and prognosis in stroke patients.

METHODS

Sixty-one patients with carotid atherosclerotic plaques were selected. All patients received conventional ultrasound, CEUS, and SMI examination, including 32 patients with cerebral infarction and 29 patients without cerebral infarction. The results of CEUS and SMI neovascularization of patients were graded 0, 1, and 2 points according to the image characteristics. The consistency between SMI results and CEUS results was evaluated, and the differences in neovascularization in carotid plaques between patients with cerebral infarction and those without cerebral infarction were compared.

RESULTS

SMI showed that the neovascularization score in plaque was 0 point in 13 cases, 1 point in 24 cases, and 2 points in 24 cases. There were no significant differences in age, sex, plaque size, or echo between the two groups. There was no significant difference between the SMI and CEUS results, P > .05. The CEUS neovascularization grade of patients with cerebral infarction had a higher score, which was significantly different from that of patients without cerebral infarction, P < .05. The SMI neovascularization grade of patients with cerebral infarction had a higher score, which was significantly different from that of patients without cerebral infarction, P < .05.

CONCLUSION

SMI can show neovascularization in plaques, with a significantly higher grade of neovascularization in those of patients with cerebral infarction than in those without cerebral infarction.

Noninvasive Visualization of Tumor Blood Vessels within Hepatocellular Carcinoma by Application of Superb Microvascular Imaging to Contrast-Enhanced Ultrasonography

The combination or sequential use of systemic therapies, such as lenvatinib and locoregional therapies, can improve the curability rate of hepatocellular carcinoma. This is based on the notion that lenvatinib remodels abnormal tumor vessels into normal vessels, potentially enhancing the efficacy of locoregional therapies. In this case report, we achieved noninvasive visualization of tumor blood vessels by applying superb microvascular imaging (SMI) to contrast-enhanced ultrasonography (CEUS). A man in his 80s with a borderline resectable hepatocellular carcinoma received preoperative therapy using lenvatinib. The patient achieved a complete response after lenvatinib therapy, underwent hepatectomy, and maintained a cancer-free status. CEUS and SMI revealed a decrease in tumor blood vessels at 1 week after lenvatinib administration and a decrease in tumor perfusion at 2 weeks. Although CEUS alone is adequate for noninvasive real-time evaluation of tumor perfusion, it is not sufficient to achieve accurate assessments of tumor blood vessels. We performed a noninvasive time-course evaluation of vascular normalization after lenvatinib administration by applying SMI. The evaluation of vascular normalization with lenvatinib therapy using CEUS and SMI can support the decision to proceed to conversion therapies.

The place of B-mode ultrasonography, shear-wave elastography, and superb microvascular imaging in the diagnosis of De Quervain tenosynovitis

PURPOSE

Superb microvascular imaging (SMI) and Shear wave elastography (SWE) are newly developed ultrasonographic diagnostic tools used to support the diagnosis of De Quervain tenosynovitis (DQT). The aim of this study was to examine the capacity to differentiate between the wrist with DQT and the healthy wrist, as well as the potential for predicting the disease's severity using B-mode ultrasonography, SWE, and SMI.

METHODS

A total of 19 cases with unilateral clinical DQT were included in the prospective study. The wrists of these cases without DQT clinic constituted the control group.

RESULTS

The SWE parameters of m/s and kPa cutoff values were ≤5.225 and ≤ 77.65, respectively, in the wrists with DQT compared to the wrists not diagnosed with DQT (p < 0.001). Regarding SMI findings no microvascularity was determined in the abductor pollicis longus (APL) and extensor pollicis brevis (EPB) tendon sheaths of the wrists without DQT, and a significant increase was observed in the degree of microvascularity as the clinical severity of DQT increased.

CONCLUSION

SWE results can differentiate between the presence and absence of DQT. SMI grading of the APL and EPB tendon sheaths may be helpful to the clinician in deciding the clinical severity of DQT.

Evaluation of placenta in patients with gestational diabetes using shear wave elastography and superb microvascular imaging

BACKGROUND

Gestational diabetes mellitus (GDM) is a common disease, and the placenta shows various functional and morphological changes in these patients. Superb microvascular imaging (SMI) and shear wave elastography (SWE) are innovative ultrasound (US) methods that provide detailed information about tissue vascularization and elasticity.

PURPOSE

To evaluate placental changes in patients with GDM with SMI and SWE methods.

MATERIAL AND METHODS

For this case-control study, 20 healthy and 20 women with GDM were included. Women at >21 weeks of pregnancy were evaluated with SMI and SWE by two independent radiologists. Mean SMI values and mean SWE values from three different region of interest-based measurements were compared between the two groups.

RESULTS

We identified that the mean SMI and SWE value ​​of the GDM group was found to be significantly higher than that of the control group (P = 0.002, P = 0.001 respectively). Using a receiver operating characteristic curve, the cutoff value of the SMI ratio, which maximizes the prediction of the presence of GDM, was 0.1234279750 (95% confidence interval [CI] = 0.625-0.920), the SWE cut-off value was 15.5 kPa (95% CI = 0.794-0.989).

CONCLUSION

We have demonstrated that evaluation with SMI and SWE might allow quantitative assessment of the morphological changes of placentas in women with GDM. We believe that the use of innovative methods such as SMI and SWE in addition to conventional US examinations in daily practice and studies will provide significant clinical benefits to patient management.

Diagnostic performance of ACR-TIRADS combined with superb microvascular imaging for differential diagnosis of mummified thyroid nodules and papillary thyroid carcinomas

Objective

The aim was to investigate the ability of superb microvascular imaging (SMI) to improve the differential diagnosis of mummified thyroid nodules (MTNs) and papillary thyroid carcinomas (PTCs) using the 2017 American College of Radiology Thyroid Imaging Reporting and Data System (ACR-TIRADS).

Materials and methods

We enrolled 110 cases of MTNs and 110 cases of PTCs confirmed by fine needle aspiration (FNA) or surgery. Conventional ultrasound (US) and the quantity of microvessels detected by SMI were analyzed for all nodules. Thyroid nodules were initially categorized by ACR-TIRADS based on US imaging features and then reclassified based on ACR-TIRADS combined with SMI blood-flow grade (SMI-TIRADS). We compared the diagnostic performances of ACR-TIRADS and SMI-TIRADS by receiver operating characteristic curve, sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV).

Results

US-detected margin, shape, and echogenic foci differed between MTNs and PTCs (P < 0.05). The SMI blood-flow grade was significantly greater in PTCs compared with MTNs (Χ2 = 158.78, P < 0.05). There was no significant difference in ACR-TIRADS indicators between MTNs and PTCs (Χ2 = 1.585, P = 0.453); however, reclassification by SMI-TIRADS showed significant differences between the groups (Χ2 = 129.521, P < 0.001). The area under the curve was significantly lower for ACR-TIRADS compared with SMI-TIRADS (0.517 vs 0.887, P < 0.05). SMI-TIRADS had significantly higher diagnostic value for distinguishing MTNs and PTCs than ACR-TIRADS (sensitivity: 91.82% vs 74.55%, P < 0.05; specificity: 84.55% vs 21.82%, P < 0.05; accuracy: 88.18% vs 48.18%, P < 0.05; PPV: 85.59% vs 48.81%, P < 0.05; and NPV: 91.18% vs 46.15%, P < 0.05).

Conclusion

The detection of microvascular flow and large vessels in thyroid nodules by SMI resulted in high diagnostic specificity and sensitivity. ACR-TIRADS combined with SMI could effectively distinguish between MTNs and PTCs, to avoid unnecessary FNA or surgical excision.

The value of multimodal ultrasonography in the evaluation of late presenting testicular torsion in a rat experimental model

OBJECTIVE

To evaluate the value of multimodal ultrasonography (US) in a rat experimental torsion model after 6 h of torsion with different degrees.

METHODS

Twenty-one male rats were divided into three groups. Left testes of the rats were twisted around their vascular pedicle 360 degrees in group 1, 720 degrees in group 2, and 1080 degrees in group 3 and intact right testes of the rats were accepted as control group. Grey-scale US, superb microvascular imaging (SMI), colour Doppler ultrasonography (CDUS), strain elastography (SE), and two-dimensional (2-D) shear wave elastography (SWE) examinations were applied 6 h after torsion procedure and testes were removed for pathological evaluation.

RESULTS

Short-axis dimensions and volumes of the torsion side were higher than control testes. Lengths of the testes in the 3rd torsion group were smaller than the testes in groups 1 and 2 (P < 0.002). SMI was better than CDUS in recognizing blood flow in testicular tissue. Strain ratios were higher in group 1 and decreased with the increasing torsion degree. Emean and standard deviation (SD) measurements increased in the torsion side. Pathologically the mean testicular damage scores were statistically significant between torsion and control testes in all groups.

CONCLUSION

Our results showed that short-axis and volume measurements, SMI, 2D-SWE, and SE are effective in the evaluation and diagnosis of testicular torsion (TT).

ADVANCES IN KNOWLEDGE

Evaluation of affected testis and intact testis with multiparametric US in late presenting TT cases is more reliable than being dependent on a single sonographic modality.

Usefulness of Ultrasonographic Detective Flow Imaging for Detecting Parathyroid Tumors: A Report of Two Cases

Parathyroid tumors (PTs) are sometimes difficult to diagnose because they are small and have low-velocity blood flow, which can be missed by current imaging modalities. PTs consist of parathyroid adenoma (PA), parathyroid cyst, and parathyroid carcinoma (PC). Detective flow imaging (DFI) is a new imaging technology that displays low-velocity blood flow. Herein, we report two cases in which DFI was useful for diagnosis of PTs. One patient had a PA and a parathyroid cyst in close proximity, and the other had a PC. To our knowledge, this is the first report to demonstrate the usefulness of DFI in the diagnosis of PTs.

Assessment of the carpal tunnel and associated neural structures with superb microvascular imaging: a scoping review

INTRODUCTION

Superb microvascular imaging (SMI) is an advanced ultrasound technique that portrays microcirculation. Its clinical applications have been studied in various diseases, including carpal tunnel syndrome (CTS) i.e. the most common entrapment neuropathy. This scoping review explores the role of SMI in diagnosing CTS or the assessment of relevant neural structures.

METHODS

We conducted a comprehensive search of electronic databases (PubMed, Embase and Web of Science) up to 26 September 2023. Two independent authors conducted the literature search, quality assessment, and data extraction.

RESULTS

This review includes seven studies comprising 385 wrists. SMI consistently revealed increased intraneural vascularity in the median nerves of patients with CTS compared to healthy individuals. While SMI demonstrated higher sensitivity than traditional Doppler methods for detecting CTS, its specificity was somewhat lower. Combining SMI with B-mode ultrasound appears to enhance the diagnostic accuracy for CTS. However, the relationship between SMI findings and CTS severity remains unclear.

CONCLUSIONS

This review highlighted the ability of SMI to provide detailed vascular structures in both healthy wrists and those with CTS. Additional research is crucial to determine the typical SMI findings of the carpal tunnel and within that context, tailor more precise diagnostic/therapeutic applications for the CTS population.

Longitudinal assessment of spiral and uterine arteries in normal pregnancy using novel ultrasound tool

OBJECTIVES

To use superb microvascular imaging (SMI) to evaluate longitudinally spiral artery (SA) and uterine artery (UtA) vascular adaptation in normal human pregnancy, and to develop reference ranges for use at various gestational ages throughout pregnancy.

METHODS

The data for this study were obtained from the National Institutes of Health (NIH)-funded Human Placenta Project. Women aged 18-35 years, with a body mass index < 30 kg/m2 , without comorbidities, with a singleton gestation conceived spontaneously, and gestational age at or less than 13 + 6 weeks were eligible for inclusion. The current analysis was restricted to uncomplicated pregnancies carried to term. Exclusion criteria included maternal or neonatal complications, fetal or umbilical cord anomalies, abnormal placental implantation or delivery < 37 weeks. Women who fulfilled the inclusion criteria formed the reference population of the Human Placenta Project study. Each participant underwent eight ultrasound examinations during pregnancy. The pulsatility index (PI) of both the left and right UtA were obtained twice for each artery and the presence or absence of a notch was noted. Using SMI technology, the total number of SA imaged was recorded in a sagittal placental section at the level of cord insertion. The PI and peak systolic velocity (PSV) were also measured in a total of six SA, including two in the central portion of the placenta, two peripherally towards the uterine fundal portion, and two peripherally towards the lower uterine segment.

RESULTS

A total of 90 women fulfilled the study criteria. Maternal UtA-PI decreased throughout the first half of pregnancy from a mean ± SD of 1.39 ± 0.50 at 12-13 weeks' gestation to 0.88 ± 0.24 at 20-21 weeks' gestation. The mean number of SA visualized in a sagittal plane of the placenta increased from 8.83 ± 2.37 in the first trimester to 16.99 ± 3.31 in the late-third trimester. The mean SA-PI was 0.57 ± 0.12 in the first trimester and decreased progressively during the second trimester, reaching a nadir of 0.40 ± 0.10 at 24-25 weeks, and remaining constant until the end of pregnancy. SA-PSV was highest in early pregnancy with a mean of 57.16 ± 14.84 cm/s at 12-13 weeks' gestation, declined to a mean of 49.38 ± 17.88 cm/s at 20-21 weeks' gestation and continued to trend downward for the remainder of pregnancy, reaching a nadir of 34.50 ± 15.08 cm/s at 36-37 weeks' gestation. A statistically significant correlation was noted between SA-PI and UtA-PI (r = 0.5633; P < 0.001). Multilevel regression models with natural cubic splines were used to create reference ranges of SA-PSV and SA-PI for given gestational ages.

CONCLUSION

From early gestation, we have demonstrated the ability to image and quantify SA blood flow in normal pregnancy, and have developed reference ranges for use at various gestational ages throughout pregnancy. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Evaluation of nipple vascularity using superb microvascular imaging in patients with reduction mammoplasty

We aimed to investigate the effect of the chosen pedicle on nipple vascularity by evaluating changes in the microvascular circulation of the nipples in patients undergoing reduction mammoplasty through superb microvascular imaging study (SMI). 70 nipples were included in this retrospective study. There were 15 patients (30 nipples) in Group A using the inferior pedicle and 20 patients (40 nipples) in Group B using the superomedial pedicle. The vascular index (VI) of each nipple were evaluated preoperatively and at the third postoperative month using SMI. The mean VI in Group A was 1.25 (0.5-3.6) preoperatively and 1.3 (0.4-3.2) at the third postoperative month (P > .05). The mean VI in Group B was 1.65 (0.7/2.9) preoperatively and 1.15 (0.2/1.9) at the third postoperative month (P < .05). While the VI increased by 11.3% in Group A, it decreased by 30.6% in Group B (P < .001). The changing of the VI was analyzed between comparable groups, and decreasing microvascular circulation of the nipple with use of the superomedial pedicle was detected by quantitative values, which can be useful in at-risk patient groups, the planning of surgical procedures, and early revisions at postoperative month 3.

Development of a novel combined nomogram model integrating deep learning radiomics to diagnose IgA nephropathy clinically

This study aimed to develop and validate a combined nomogram model based on superb microvascular imaging (SMI)-based deep learning (DL), radiomics characteristics, and clinical factors for noninvasive differentiation between immunoglobulin A nephropathy (IgAN) and non-IgAN.We prospectively enrolled patients with chronic kidney disease who underwent renal biopsy from May 2022 to December 2022 and performed an ultrasound and SMI the day before renal biopsy. The selected patients were randomly divided into training and testing cohorts in a 7:3 ratio. We extracted DL and radiometric features from the two-dimensional ultrasound and SMI images. A combined nomograph model was developed by combining the predictive probability of DL with clinical factors using multivariate logistic regression analysis. The proposed model's utility was evaluated using receiver operating characteristics, calibration, and decision curve analysis. In this study, 120 patients with primary glomerular disease were included, including 84 in the training and 36 in the test cohorts. In the testing cohort, the ROC of the radiomics model was 0.816 (95% CI:0.663-0.968), and the ROC of the DL model was 0.844 (95% CI:0.717-0.971). The nomogram model combined with independent clinical risk factors (IgA and hematuria) showed strong discrimination, with an ROC of 0.884 (95% CI:0.773-0.996) in the testing cohort. Decision curve analysis verified the clinical practicability of the combined nomogram. The combined nomogram model based on SMI can accurately and noninvasively distinguish IgAN from non-IgAN and help physicians make clearer patient treatment plans.

The Diagnostic Role of Shear Wave Elastography and Superb Microvascular Imaging in the Evaluation of Suspicious Microcalcifications

OBJECTIVES

The aim of this study was to investigate the role of superb microvascular imaging (SMI) and shear wave elastography (SWE) in the prediction of malignancy and invasiveness of isolated microcalcifications (MC) that can be visualized by ultrasonography (US).

MATERIAL AND METHODS

Sixty-seven women with MC, who were considered suspicious on mammography were evaluated. Only those lesions that could be visualized by US and presented as non-mass lesion were included. They were evaluated by B-mode US, SMI, and SWE before US-guided core-needle biopsy. B-mode US, SMI (vascular index (SMIvi)), and SWE (E-mean, E-ratio) findings were compared with histopathologic features.

RESULTS

Pathology confirmed 45 malignant (21 invasive and 24 in situ carcinomas) and 22 benign lesions. There was a statistically significant difference between malignant and benign groups in terms of size (P = .015), distortion (P = .028), cystic component (P < .001), E-mean (P < .001), E-ratio (P < .001), and SMIvi (P = .006). For differentiation of invasiveness E-mean (P = .002), E-ratio (P = .002), and SMIvi (P = .030) were statistically significant. According to ROC analysis E-mean (cut-off point at 38 kPa) was the most sensitive (78%) and the most specific (95%) value among four numeric parameters (size, SMI, E-mean, and E-ratio) with AUC = 0.895, PPV = 97%, and NPV = 68% in detecting malignancy. In the evaluation of invasiveness, the most sensitive (71.4%) method was SMI (cut-off point at 3.4) and the most specific (72%) method was E-mean (cut-off point at 91.5 kPa).

CONCLUSION

Our study shows that adding SWE and SMI to the sonographic evaluation of MC would be an advantage for US-guided biopsy. Including suspicious areas according to SMI and SWE in the sampling area can help target the invasive part of the lesion and avoid underestimation of core biopsy.

Superb Microvascular Imaging at Evaluation of Nonvisible Buried De-epitelized Flap Vascularization in Breast Reconstruction

OBJECTIVE

Superb microvascular imaging is a Doppler technique that increases the visibility of small vessels and gives quantitative information about tissue blood supply by measuring the vascular index. In this study, it is aimed to evaluate the long-term and postradiotherapy changes in blood flow of buried de-epitelized flaps in breast reconstruction by using the quantitative values obtained through superb microvascular imaging.

MATERIALS AND METHODS

Retrospective review of the 14 patients who underwent nipple-sparing breastconserving surgery and immediately breast reconstruction with a de-epitelized extended latissimus dorsi flap was done. In order to demonstrate the effect of radiotherapy on flaps microvascular circulation, patients were evaluated using superb microvascular imaging postoperative first week, first month, and postradiotherapy first week and sixth month. The normal distribution of the data was evaluated with the Shapiro-Wilk test. Paired samples t-test was used for comparisons.

RESULTS

According to the paired samples t-tests, postoperative first week mean vascular index was higher than postoperative first month and postradiotherapy first week (P < .05). Besides, postradiotherapy first week mean vascular index was higher than postoperative first month and also than postradiotherapy sixth month (P < .05).

CONCLUSION

Radiotherapy can affect the results of breast reconstruction by endothelial and fibrotic injury. In this study, the changes in the microvascular circulation of the latissimus dorsi flap were discussed and found to increase at postoperative and postradiotherapy early period related to inflammation and not decreased significantly at long-term follow-up after radiotherapy.

The Use of Superb Microvascular Imaging in Evaluating Rheumatic Diseases: A Systematic Review

Background and Objectives: Superb microvascular imaging is an advanced Doppler algorithm that seems to be useful in detecting low-velocity blood flow without using a contrast agent. Increasing evidence suggests that SMI is a more sensitive tool than conventional Doppler techniques for evaluating rheumatic diseases, especially inflammatory arthritis. We aimed to assess the use of SMI in evaluating joints and extraarticular structures. Materials and Methods: Two reviewers independently reviewed the literature to provide a global overview of the possibilities of SMI in rheumatology. Original English-language articles published between February 2014 and November 2022 were identified through database (PubMed, Medline, Ebsco, the Cochrane Library, and ScienceDirect) searching, and analysed to summarise existing evidence according to PRISMA methodology. Inclusion criteria covered original research articles reporting applications of SMI on rheumatic diseases and musculoskeletal disorders secondary to rheumatic conditions. Qualitative data synthesis was performed. Results: A total of 18 articles were included. No systematic reviews fulfilled our inclusion criteria. Most studies focused on characterising the synovial vascularity of rheumatoid arthritis. There have been several attempts to demonstrate SMI's value for evaluating extra-articular soft tissues (fat pads or salivary glands) and large-diameter vessels. The quantitative importance of SMI vascular indices could become a useful non-invasive diagnostic marker. Studies on therapeutic applications are still scarce, and the majority of studies have gaps in reporting the methodology (ultrasound performance technique and settings) of the research. Conclusions: SMI has proved to be useful in characterising low-flow vascularity, and growing evidence indicates that SMI is a non-invasive and lower-cost tool for prognostic assessment, especially in inflammatory arthritis. Preliminary findings also suggest potential interest in evaluating the effect of treatment.

Differentiation of Active Ulcerative Colitis vs Noninflammatory Bowel Disease Proctitis by Transperineal Superb Microvascular Imaging

BACKGROUND

Transabdominal ultrasonography and transperineal ultrasonography (TPUS) appear correspond to colonoscopy (CS) for evaluating ulcerative colitis (UC) activity, but their utility in UC diagnosis remains unclear. This research compared the accuracy of TPUS and CS for assessing rectal activity and differentiating noninflammatory bowel disease proctitis from UC in pediatric cases.

METHODS

The study is a blinded, prospective, and controlled trial. Prospectively, values of fecal calprotectin (FCP) and findings of the TPUS and CS were compared between child cases of UC and non-IBD proctitis. Findings of rectal wall thickening (RWT), rectal wall flow (RWF) on power Doppler, and microvascular signal at wall circumference (MSWC) on monochrome superb microvascular imaging assessed using TPUS were compared with the CS.

RESULTS

Thirty patients with Mayo endoscopic subscore (MES) 0 to 1 UC, 57 with MES 2 to 3 UC, and 44 with proctitis were registered. Fecal calprotectin, RWF, and MSWC indicated significant differences among the groups (P < .05). Rectal wall thickening showed no significant difference between MES 0-1 and proctitis (P = .76). Rectal wall thickening and MSWC were independent predictors of endoscopic activity of UC, resulting in a sensitivity and specificity of 100% for RWT ≥4.5 mm and positive MSWC. Fecal calprotectin and RWF were independent predictors for differentiating MES 0 to 1 and proctitis, and FCP and RWT were independent predictors for differentiating MES 2 to 3 and proctitis. Sensitivity and specificity were 77.2% and 80.9%, respectively, for FCP >242.5 μg/g and RWF negative; and they were both 100% for RWT >4.1 mm and MSWC positive.

CONCLUSIONS

Transperineal ultrasonography with mSMI may enable the evaluation of rectal activity and differentiation of UC from non-IBD proctitis with accuracy comparable to endoscopy.

Potential diagnostic value of quantitative superb microvascular imaging in premalignant and malignant cervical lesions

Objective

The purpose of this study was to assess the diagnostic efficacy of the vascular index (VI) on superb microvascular imaging (SMI) in distinguishing normal uterine cervical epithelium, high-grade cervical intraepithelial neoplasia (CIN), and cervical cancer.

Methods

The retrospective study included women with pathology-confirmed CIN or cervical cancer, who underwent transvaginal ultrasound and SMI between April 2021 and October 2022. The SIM manifestations of normal cervix and cervical lesions were reviewed. SIM were measured and converted into vascular index (VI) which compared between cervical lesions and control groups. We have retrospectively compared ultrasound features of cervical lesions and characteristics of patients. Measurement reliability was evaluated by intra class correlation coefficient (ICC).

Results

A total of 235 consecutive females were enrolled, comprising 38 with high-grade CIN, 96 with cervical cancer, and 101 with a normal uterine cervix. The microvascular architecture exhibited significant variations between premalignant and malignant cervical lesions. Branch-like patterns were predominantly observed in high-grade CIN, while crab claw-like and fireball-like patterns were more commonly associated with cervical cancer. The median VI of cervical cancer (34.7 ± 10.3) was significantly higher than that of high-grade CIN (17.6 ± 4.2) (P < 0.001). Moreover, the VI values of cervical cancer differed significantly among different FIGO stages and pathological types (P < 0.001 and P = 0.003, respectively). The VI demonstrated superior diagnostic performance for cervical lesions compared to vascular patterns (AUC = 0.974 and 0.969, respectively). Using a cut-off value of 25.5, the VI yielded a sensitivity of 82.3% and a specificity of 99.3% for cervical lesion detection.

Conclusions

The SMI parameter (VI) exhibited a significantly higher value in cervical cancer compared to high-grade CIN, with a high level of agreement among observers. These findings suggest that quantitative SMI holds promise as an imaging technique for the detection and characterization of cervical lesions.

Intraneural vascularity of the median, ulnar and common peroneal nerve: Microvascular ultrasound and pathophysiological implications

Objectives

Changes in the microvascular environment are considered crucial in the pathogenesis of compression neuropathies. Several studies have demonstrated elevated intraneural vascularity in severe neuropathy compared with healthy subjects, where intraneural vascularity is considered predominantly undetectable. The aim of this study was to assess and quantify intraneural vasculature by superb microvascular imaging (SMI) in healthy volunteers in the median, ulnar and common peroneal nerve.

Methods

Intraneural vascularity was quantified in 26 healthy volunteers (312 segments overall) by SMI sonography using a 22-MHz linear transducer. Individual nerve segment vascularity was compared with the mean vascularity using one-way ANOVA and Kruskal-Wallis tests, respectively. Vendor-provided quantification and manual vessel count were compared by linear regression analysis.

Results

Intraneural vascularity was detectable in all nerve segments (100.0%). Vessel density was highest in the median nerve at the wrist (1.54 ± 0.44/mm2, P < 0.0001) and lowest in the sulcal ulnar nerve (0.90 ± 0.34/mm2, P < 0.0001). Vendor-provided automated quantification severely overestimated vascular content compared with manual quantification.

Conclusion

Superb microvascular imaging can facilitate the visualisation of nerve vascularity and even detect local variations in vessel density. The pathophysiological implications for peripheral neuropathies, especially compression neuropathies, warrant further investigation, but the absence of visible intraneural vasculature as a negative finding in the diagnostic of compression neuropathies should be interpreted with caution, as the intraneural vascularity may lie beyond the 18 MHz resolution power of a transducer.

Superb Microvascular Imaging for the Differentiation of Benign and Malignant Breast Lesions: A System Review and Meta-Analysis

OBJECTIVE

To evaluate the diagnostic performance of SMI in the diagnosis of benign and malignant breast lesions.

METHODS

A systematic search of PubMed, EMBASE, Cochrane, OVID, SCI, and SCOPUS was performed to find relevant studies which applied SMI to differentiate benign and malignant breast lesions. All the studies were published before October 10, 2022. Only studies published in English were collected. Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool was applied to assess the quality of the included studies. Summary receiver operating characteristic (SROC) modeling was also performed to the diagnostic performance of SMI in the diagnosis of benign and malignant breast lesions. Subgroup analyses and meta-regression were performed to find out the heterogeneity.

RESULTS

Twenty studies which include a total of 2873 lesions (1748 benign and 1125 malignant) in 2740 patients were evaluated in this meta-analysis. The summary sensitivity and specificity were 0.82 (95% confidence interval [CI]: 0.76-0.86), 0.70 (95% CI: 0.64-0.76) for SMI vascular degree, 0.77 (95% CI: 0.67-0.84), 0.79 (95% CI: 0.75-0.83) for SMI vascular distribution, 0.78 (95% CI: 0.70-0.84), 0.75 (95% CI: 0.69-0.80) for SMI vascular morphology, 0.81 (95% CI: 0.72-0.87), 0.80 (95% CI: 0.75-0.85) SMI penetration vessel. For SMI overall vascular features, the summary sensitivity and summary specificity were 0.74 (95% CI: 0.61-0.84) and 0.80 (95% CI: 0.76-0.84). The result of subgroup analysis and meta-analysis showed malignant rate and country might be the cause of heterogeneity of diagnostic accuracy of vascular grade and morphology.

CONCLUSION

SMI vascular features have high sensitivity and specificity in the differentiation of benign and malignant lesions. Future international multicenter studies in various regions with large sample size are required to confirm these findings.

The feasibility of early response evaluation using superb microvascular imaging one day after transcatheter arterial chemoembolization for hepatocellular carcinoma

PURPOSE

The purpose of this study was to determine the feasibility of early Superb microvascular imaging (SMI) for prediction of the effect of HCC treatment after transcatheter arterial chemoembolization (TACE).

MATERIALS AND METHODS

A total of 96 HCCs (70 patients) treated with TACE between September 2021 and May 2022 were included in this study. SMI, Color Doppler imaging (CDI), and Power Doppler imaging (PDI) were performed the day after TACE for evaluation of intratumoral vascularity of the lesion using an Aplio500 ultrasound scanner (Toshiba Medical Systems, Corporation, Tochigi, Japan). Grading of the vascular presence was performed using a five-point scale. A dynamic CT image taken after 29-42 days was used for comparison of sensitivity, specificity, and accuracy for detection of tumor vascularity between SMI, CDI, and PDI. Univariate and multivariate analysis were performed for assessment of factors affecting intratumoral vascularity.

RESULTS

Fifty-eight lesions (60%) showed complete remission (CR) and 38 lesions (40%) showed partial response (PR) or no response at 29-42 days on Multi-detector Computed Tomography (MDCT) after TACE. SMI showed sensitivity of 86.84% for detection of intratumoral flow, which was significantly higher compared with that of CDI (10.53%, p < 0.001) and PDI (36.84%, p < 0.001). The results of multivariate analysis indicated that tumor size was a significant factor in detection of blood flow using the SMI technique.

CONCLUSION

Early SMI may be utilized as an adjunctive diagnostic test for evaluation of treated lesions after TACE, particularly when the location of the tumor is in an area of the liver where a suitable sonic window can be identified.

Comparison of conventional Doppler imaging techniques and superb microvascular imaging in determination of vascularization in undescended testes

Aim

Our aim was to gain an idea about testicular injury by comparing the reduced volume, which is one of the indirect indicators of testicular damage in undescended testes, and by evaluating the reduced microvascular blood flow by superb microvascular imaging, and also to determine whether superb microvascular imaging modes could detect microvascular blood flow in more detail in the decreased volume of undescended testes.

Material and methods

We compared testicular blood flow in undescended testes via conventional Doppler imaging, color superb microvascular imaging, and monochrome superb microvascular imaging techniques with contralateral normally located testis and normal control group. Each sample of testicular tissue was evaluated using a qualitative method. Spot color encoding and linear flow color encoding counts determined in testicular parenchyma were counted separately and expressed as numerical data. The localization of the examined testes in the grayscale was noted (proximal inguinal canal, medial inguinal canal, distal inguinal canal, and scrotal). The volume of undescended testes was calculated automatically via a formula for volume.

Results

Monochrome superb microvascular imaging is significantly superior in visualizing the vascularity of undescended testes compared with color Doppler, power Doppler and color superb microvascular imaging (p = 0.001). Also, undescended testes have a significantly lower blood flow compared with contralateral normal testes (p = 0.001). The volume of undescended testes was significantly lower than the contralateral normal testes.

Conclusions

The volume, structure and blood flow are indirect signs of testicular damage in undescended testes. Monochrome superb microvascular imaging can detect vascularity in undescended testes better than the conventional Doppler imaging technique and color superb microvascular imaging. Based on our findings, we can report that monochrome superb microvascular imaging can be used to evaluate testicular injury and vascularity of undescended testes.

The role of superb micr ole of superb microvascular imaging in detecting low-gr ascular imaging in detecting low-grade inflammation among adults and those with chronic kidney disease: A preliminary study

BACKGROUND

Pathophysiologic changes associated with chronic inflammation occur with aging and more prominently in patients with chronic kidney disease (CKD), and an association between chronic inflammation and muscle wasting has been identified. The microcirculation is extremely sensitive to the inflammatory process and actively participates in it. In a healthy adult, angiogenesis is a strictly controlled and rare occurrence. However, aberrant angiogenesis and the development of new tiny blood vessels are known in chronic inflammatory diseases. Superb microvascular imaging (SMI) is a noninvasive technique that can evaluate tiny vessels with low blood flow and provide quantitative data. Our goal was to detect increased blood flow secondary to low-grade chronic inflammation in micro-circulation in the rectus femoris (RF) muscle using SMI.

METHODS

This cross-sectional study involved 30 patients with CKD, 30 adults without CKD or other chronic illnesses, and 32 young healthy volunteers. This study was conducted in our university hospital between March and December 2021. The RF cross-sectional area (CSA) was measured, and vascular index (VI) values were obtained using SMI. All three groups' RF-CSA and VI values were compared.

RESULTS

Although there was no statistically significant difference in RF-CSAs between the groups, the VI values of all three groups were statistically different (p < 0.001). The median (min-max) VI values were 0.90 (0.60-1.30), 0.50 (0.20-1.0), and 0.30 (0.10-0.50) for the CKD, adult control, and young healthy groups, respectively. The VI significantly differentiated patients with CKD from all other patients and the adult control group. When a cutoff value of 6.5 was used for the VI in detecting increased blood supply in RF muscle in patients with CKD, the accuracy, positive predictive value, and negative predictive value were 93.5%, 85.3%, and 98.3%, respectively.

DISCUSSION

SMI can detect increased blood supply caused by low-grade inflammation in the RF muscle.

Multiparametric ultrasound images of three different cases of schwannoma of the peripheral nervous system

This case image illustrates the importance of new sonographic applications such as superb microvascular imaging and shear wave elastography; as showed, they improve the diagnostic recognition of peripheral nerve lesion thanks to a better definition of vascularity and measure of stiffness.

A comparison between the superb microvascular imaging technique and conventional Doppler ultrasound in evaluating chronic allograft damage in renal transplant recipients

PURPOSE

The present study comparatively evaluates the performance of conventional Doppler ultrasound and superb microvascular imaging (SMI) in delineating the cortical microvessels of the transplanted kidney and compares the chronic allograft damage index (CADI) based on the examination of biopsy specimens with Doppler ultrasound and SMI findings.

METHODS

Sixty-eight renal transplant recipients underwent kidney biopsy with the pre-diagnosis of rejection before undergoing renal Doppler ultrasound examination between January 2020 and October 2020. The distance between the kidney capsule and the vascular structure closest to the kidney capsule was measured at the level of the lower pole in the transplanted kidney using color Doppler ultrasound (CDUS), power Doppler ultrasound (PDUS), and the SMI technique. The kidney size, resistive index at the level of the arcuate artery in the lower pole of the kidney, and renal artery flow rates were also measured.

RESULTS

The mean distance between the kidney capsule and the vessel was 2.44 ± 2.0 mm on CDUS, 1.34 ± 1.2 mm on PDUS, 0.99 ± 1.8 mm using the color SMI (cSMI) technique, and 0.86 ± 1.8 mm using the monochrome SMI (mSMI) technique. The study found that the SMI technique was superior to CDUS and PDUS in delineating the cortical microvasculature of the kidney. Both Doppler ultrasound examinations and the SMI technique proved effective in predicting the CADI (P = 0.006 for CDUS, P = 0.002 for PDUS, P = 0.018 for cSMI, and P = 0.027 for mSMI). Among conventional Doppler ultrasound examinations and the SMI technique, PDUS had the highest sensitivity, and cSMI had the highest specificity in differentiating high and low CADI values. Both the cSMI and mSMI techniques had similar sensitivity values, whereas only cSMI exhibited high specificity. CDUS had the lowest specificity value (P = 0.003 for CDUS, P = 0.002 for PDUS, P = 0.005 for cSMI, and P = 0.004 for mSMI).

CONCLUSION

The present study is the first in the literature to demonstrate the utility of the distance between the kidney capsule and the vessels in predicting the CADI score and to compare the Doppler ultrasound examinations and SMI technique in doing so.

Contribution of the Ultrasound Techniques in the Evaluation of Knee Joint Damage in the Case of Pigmented Villonodular Synovitis and Rheumatoid Arthritis

OBJECTIVES

This is a prospective study to evaluate the clinical value of high-frequency ultrasound (HFUS), superb microvascular imaging (SMI), and contrast-enhanced ultrasound (CEUS) in differentiation of pigmented villonodular synovitis (PVNS) and highly active rheumatoid arthritis (RA).

METHODS

Twenty PVNS patients and 24 active RA patients were selected to undergo HFUS, SMI, and CEUS examinations. The characteristics of HFUS, SMI, and CEUS in PVNS and RA were compared, and the differential diagnosis performances of HFUS, SMI, and CEUS in PVNS and RA were evaluated by receiver operating characteristic (ROC) analysis.

RESULTS

There were statistically significant in joint effusion, synovial thickness, synovial morphology, synovial echo, synovial vessel shape, synovial enhanced direction, and enhanced pattern between PVNS and RA (P < .05). However, no statistically significant were found in bone erosion, synovial boundary, blood signal grading of synovium, synovial enhanced strength, and CEUS quantitative parameters (including PI, TTP, S, MTT, and AUC) (P > .05). The AUC of HFUS, SMI, and CEUS for differential diagnosis PVNS and RA were 0.832, 0.675, and 0.817, respectively. The AUC of HFUS + SMI, HFUS + CEUS, SMI + CEUS, HFUS + SMI + CEUS were 0.923, 0.940, 0.817, and 0.940, respectively. The AUC of HFUS + SMI and HFUS + CEUS was higher than that of each alone (P < .05).

CONCLUSIONS

HFUS, SMI, and CEUS can be used as supplementary methods for diagnosis and differential diagnosis in PVNS and active RA. What is more, the combination of HFUS + SMI and HFUS + CEUS was suggested.

Ligamentum Flavum Rupture by Epidural Injection Using Ultrasound with SMI Method

The loss of resistance (LOR) method has been used exclusively to identify epidural space. It is difficult to find the epidural space without the risk of dural puncture. Various devices have been developed to improve the accuracy of the LOR method; however, no method has overcome the problems completely. Therefore, we devised a ligamentum flavum rupture method (LFRM) in which the needle tip is placed only on the ligamentum flavum during the epidural injection, and the injection pressure is used to rupture the ligamentum flavum and spread the drug into the epidural space. We confirmed the accuracy of this method using ultrasound with superb microvascular imaging (SMI) to visualize the epidural space. Here, we report two cases of 63-year-old and 90-year-old males. The 63-year-old patient presented with severe pain in his right buttock that extended to the posterior lower leg. The 90-year-old patient presented with intermittent claudication every 10 min. LFRM was performed, and SMI was used to confirm that the parenteral solution had spread into the epidural space. Our results indicate that LFRM can be used for interlaminar lumbar epidural steroid injections.

Quantitative analysis of superb microvascular imaging for monitoring tumor response to chemoradiotherapy in locally advanced cervical cancer

Objectives

As an ultrasound (US) image processing method, superb microvascular imaging (SMI) extracts and visualizes flow signals from vessels through advanced clutter suppression technology. We investigated the feasibility of SMI in monitoring treatment response in patients with locally advanced cervical cancer (LACC) undergoing chemoradiotherapy (CRT).

Methods

Forty-nine patients underwent CRT and received SMI examination at 3 time points: before therapy (baseline), 3 weeks during, and 1 month after CRT. The maximum tumor diameter (Dmax), vascularity index (VI), and their percentage changes (ΔDmax and ΔVI) were calculated. ΔDmax was compared with MRI results as the reference standard.

Results

Based on the MRI findings, 44 were classified as complete response (CR) group and 5 as partial response (PR) group. The Dmax and ΔDmax showed decrease in CR and PR groups at 3 weeks during CRT (P< 0.05), but no significant difference between the two groups (P > 0.05). Compared to the baseline, significant decrease in VI and ΔVI were observed at during and after treatment in the two groups (P< 0.05). Moreover, there were significant differences in VI and ΔVI at 3 weeks during CRT between the CR and PR groups (P< 0.05). ΔVI at 3 weeks during CRT showed a better predictive performance for responder prognosis than VI (AUC = 0.964, AUC = 0.950, respectively, P = 0.001), with a cut-off value of 41.6% yielding 100% sensitivity and 86.4% specificity.

Conclusions

The SMI parameters (VI and ΔVI) have potential for monitoring treatment response in LACC.

Ultrasonographic Evaluation of Intravenous Lobular Capillary Hemangioma in the Cephalic Vein

A 60-year-old man presented with focal swelling on the dorsal surface of the left wrist. The sonographic exam revealed the presence of a smoothly rounded hypoechoic mass, with internal blood flow in the lumen of the vein. The histopathological findings led to the diagnosis of intravenous lobular capillary hemangioma (LCH). Here, we reported an intravenous LCH arising from the cephalic vein on the dorsal surface of the left wrist hand and discussed the related ultrasonographic findings.

Clinical study of carotid superb microvascular imaging in evaluating the activity of Takayasu's arteritis

Objective

The goal of this study is to use superb microvascular imaging (SMI) to observe neovascularization in the carotid vessel wall to identify potential Takayasu's arteritis (TAK) inflammation markers.

Methods

Bilateral carotid arteries from 96 patients with TAK were imaged by a Doppler ultrasound and SMI. The one-way analysis of variance (ANOVA) was used to document significant differences between the activity and inactivity stages of TAK and the factors closely related to its activity in the binary logistics regression equation. Clinical and laboratory data included age, gender, duration of disease, treatment history, NIH score, erythrocyte sedimentation rate (ESR), and high-sensitivity C-reactive protein. Imaging data included the arterial wall thickness, degree of lesion, SMI grade, and arterial aneurysm formation.

Results

There were 45 patients in the active TAK stage and 51 in the inactive stage. The one-way ANOVA showed significant differences in SMI (p = 0.001) and ESR (p = 0.022) between the active and inactive groups. The binary logistics regression analysis showed that SMI was an independent risk factor for TAK activity (B = -1.505, S.E = 0.340, Wald = 19.528, OR = 0.222 95%, CI = 0.114-0.433, p < 0.01). Using SMI G1 or G2 as the cutoff values for the diagnosis of active TAK, the positive predictive value, sensitivity, and specificity were 60 and 86%, 84% and 56%, and 54% and 92%, respectively.

Conclusion

The SMI grade is a potential marker of disease activity in patients with TAK.

Prediction of Molecular Subtypes Using Superb Microvascular Imaging and Shear Wave Elastography in Invasive Breast Carcinomas

RATIONALE AND OBJECTIVES

To investigate the efficacy of the advanced imaging methods, superb microvascular imaging (SMI) and shear wave elastography (SWE) in predicting molecular subtypes in invasive breast carcinomas.

MATERIALS AND METHODS

A total of 210 biopsy-proven breast carcinomas in 200 patients who underwent ultrasound (US) imaging with SMI and SWE were included in this study. Quantitative analyses were performed using mean elasticity (E_mean) score by SWE and vascular index (VI) by SMI. For qualitative assessment of microvascularity, first, lesions were graded according to Adler's classification in four types. Then, a new morphological model was used to classify the microvascular architecture into six patterns: type one, no signal; type two, penetrant; type three, rim-like; type four, dot-like/linear/regional; type five, wheel-like and type six, irregular signals. The correlation between these variables and molecular subtypes, nuclear grade, the Ki-67 levels and axillary status was investigated.

RESULTS

The average VI and E_mean values were relatively higher in non-luminal subtypes (VI, p = 0.002; E_mean, p > 0.05). The two microvascularisation models were significantly able to differentiate the molecular subtypes according to the Kruskal Wallis test (p < 0.05). Rim-like, penetrant and regional patterns were primarily observed in luminal subtypes. The dominant pattern in non-luminal subtypes was wheel-like pattern. VI, E_mean, Adler's classification and morphological vascularisation model were not significantly correlated with the nuclear grade, Ki-67 index or axillary status.

CONCLUSION

The proposed microvascular categorization model may be more valuable in predicting molecular subtypes of breast carcinomas compared to VI and E_mean and may contribute to the management of breast carcinomas as a non-invasive variable.

Is there a potential biomarker in distinguishing invasive breast carcinomas with elevated Ki-67 levels among 2D-SWE, SMI, and 18F-FDG PET-CT/MRI-derived parameters?: A single-center data

PURPOSE

To investigate the strength of quantitative imaging and metabolic parameters in differentiating invasive breast carcinomas with elevated Ki-67 levels.

MATERIALS AND METHODS

A total of 123 patients with 129 breast lesions confirmed as invasive breast carcinoma underwent shear wave elastography (SWE), superb microvascular imaging (SMI) and positron emission tomography (PET)/CT or MRI. Adler's grade (classifying the microvascularity into four types) and Vascular Index (VI) was obtained by SMI as microvascular parameters. In addition, the stiffness value (E_mean ) was evaluated in kilopascal by SWE. The average of consecutive measurements was recorded as mean VI and mean E_mean . PET scan parameters were obtained as SUV_max and SUL_peak . Lesions were divided into two groups according to the Ki-67 expression, low as ≤ 14 and high as >14.

RESULTS

Adler's grading was the most correlated imaging parameter with high Ki-67 expression (p < 0.05), while VI and E_mean had poor correlation (p > 0.05). SUV_max and SUL_peak indicated a significant linear correlation with Ki-67 but a moderate correlation with the high levels of Ki-67 (p < 0,001). The sensitivity of VI, E_mean , SUV_max and SUL_peak was 64.6%, 66.7%, 65.7%, and 66.7% when the cut-off point was set to 5.25, 102.5, 6.59, and 2.63, respectively. SUV_max had the highest AUC value of 0.740, according to the ROC curve analysis.

CONCLUSIONS

Our results suggest that the quantitative parameters obtained by advanced imaging methods may be useful in predicting the high proliferation in invasive breast carcinomas. But none of them is eligible to be used as an independent biomarker in distinguishing aggressive behavior. Nevertheless, as a noninvasive method, visual assessment of microvascular morphology using SMI increases the prognostic efficiency in invasive breast carcinomas.

Entrapment of the index finger radial collateral ligament in the metacarpophalangeal joint: A case report

Introduction

Digital collateral ligament injuries are common hand injuries that can cause significant pain and functional impairment. Ultrasonography can be useful in the evaluation of these ligamentous injuries, as it is both cost-effective and allows for easy, dynamic evaluation during imaging.

Case report

We report a rare sonographic finding of an index finger radial collateral ligament injury that was found to have a flap of the ligament entrapped within the metacarpophalangeal joint, which to our knowledge has not been described previously. We correlate this finding with an intraoperative image of the entrapment of the collateral ligament. We also report on the novel application of superb microvascular imaging to aid in the diagnosis of digital collateral ligament injury.

Discussion

This particular injury pattern has not been reported in the literature previously and likely explains the patient's lack of improvement with nonoperative management. Our finding is similar to a Stener lesion seen in a thumb ulnar collateral ligament injury in which the ligament is unable to heal due to entrapment. In addition, using superb microvascular imaging (SMI), we were able to visualize hyperemia to surrounding structures and the ligament itself which suggested an acute injury.

Conclusion

We anticipate that this case report will provide sonographers with knowledge and images of this specific injury pattern to the digital collateral ligaments.

Superb microvascular imaging for distinguishing thyroid nodules: A meta-analysis (PRISMA)

BACKGROUND

Earlier studies have shown that the superb microvascular imaging (SMI) can detect tumor angiogenesis to distinguish thyroid nodules, but there is no systematic review. This meta-analysis aimed to identify the accuracy of ultrasound SMI for the diagnosis of thyroid nodules.

METHODS

We searched PubMed, Cochrane Library, and CBM databases. A meta-analysis was conducted using STATA version 14.0 and Meta-Disc version 1.4 software. We calculated the summary statistics for sensitivity, specificity, positive and negative likelihood ratio (LR+/LR-), diagnostic odds ratio, and the synthetic receiver operating characteristic curve. Data will be pooled by either a fixed-effects model or a random-effects model according to the results of heterogeneity identification.

RESULTS

11 studies that met the inclusion criteria were included in this meta-analysis. The quality assessment of the study of diagnostic accuracy studies scores of all included studies were ≥22. A total of 1003 thyroid malignant nodules and 957 thyroid benign nodules were assessed. The main outcome included: the pooled sensitivity was 0.81 (95% confidence intervals (CI) = 0.79-0.84), and the pooled specificity was 0.86 (95% CI = 0.84-0.88); the pooled LR+ was 5.79 (95% CI = 4.44-7.54), and the pooled negative LR- was 0.23 (95% CI = 0.20-0.26); the pooled diagnostic odds ratio of SMI in the diagnosis of thyroid nodules was 26.84 (95% CI = 19.13-37.60). The area under the synthetic receiver operating characteristic curve was 0.89 (95% CI = 0.86-0.91). We found no evidence for publication bias (t = 0.72, P = .49).

CONCLUSION

Our meta-analysis indicates that SMI may have high diagnostic accuracy in distinguishing benign and malignant thyroid nodules.

SYSTEMATIC REVIEW REGISTRATION

INPLASY202080084.

The clinical application of ultrasonography with superb microvascular imaging-a review

Superb microvascular imaging (SMI) is among the latest doppler ultrasound methods. It uses an advanced clutter filter to eliminate artifacts caused by breathing, movement and retains the low-speed blood signals in microvessels. The great advantage of SMI is that it can intuitively detect very slow blood signals in microvessels, providing clinicians with more significant information about flow distribution in the target area. Therefore, it is speculated that SMI has important application value. The purpose of this article is to outline the application of SMI in different parts of the body.

Association Between Vascular Index Measured via Superb Microvascular Imaging and Molecular Subtype of Breast Cancer

Background

To determine whether vascular index (VI; defined as the ratio of Doppler signal pixels to pixels in the total lesion) measured via superb microvascular imaging in breast cancer correlates with immunohistochemically defined subtype and is able to predict molecular subtypes.

Methods

This prospective study involved 225 patients with 225 mass-type invasive breast cancers (mean size 2.6 ± 1.4 cm, range 0.4~5.9 cm) who underwent ultrasound and superb microvascular imaging (SMI) at Peking Union Medical College Hospital before breast surgery from December 2016 to June 2018. The correlations between primary tumor VI measured via SMI, clinicopathological findings, and molecular subtype were analyzed. The performance of VI for prediction of molecular subtypes in invasive breast cancer was investigated.

Results

The median VI of the 225 tumors was 7.3% (4.2%~11.8%) (range 0%~54.4%). Among the subtypes of the 225 tumors, 41 (18.2%) were luminal A, 91 (40.4%) were luminal B human epidermal growth factor receptor-2 (HER-2)-negative, 26 (11.6%) were luminal B HER-2-positive, 17 (7.6%) were HER-2-positive, and 50 (22.2%) were triple-negative, and the corresponding median VI values were 5.9% (2.6%~11.6%) (range 0%~47.1%), 7.3 (4.4%~10.5%) (range 0%~29.5%), 6.3% (3.9%~11.3%) (range 0.6%~22.2%), 8.2% (4.9%~15.6%) (range 0.9%~54.4%), and 9.2% (5.1%~15.3%) (range 0.7%~32.9%), respectively. Estrogen receptor (ER) negativity, higher tumor grade, and higher Ki-67 index (≥20%) were significantly associated with a higher VI value. Tumor size, ER status, and Ki-67 index were shown to independently influence VI. A cutoff value of 4.1% yielded 79.9% sensitivity and 41.5% specificity with an area under the receiver operating characteristic curve (AUC) of 0.58 for predicting that a tumor was of the luminal A subtype. A cutoff value of 16.4% yielded 30.0% sensitivity and 90.3% specificity with an AUC of 0.60 for predicting a triple-negative subtype.

Conclusions

VI, as a quantitative index obtained by SMI examination, could reflect histologic vascular changes in invasive breast cancer and was found to be higher in more biologically aggressive breast tumors. VI shows a certain degree of correlation with the molecular subtype of invasive breast cancer and plays a limited role in predicting the luminal A with high sensitivity and triple-negative subtype with high specificity.

The Role of Superb Microvascular Imaging and Shearwave Elastography in the Evaluation of Intraductal Papilloma-Like Lesions

OBJECTIVES

The aim of this study was to investigate the role of quantitative values obtained by superb microvascular imaging (SMI) and shearwave elastography (SWE) in the prediction of malignancy in intraductal papilloma-like lesions (IDPL).

METHODS

In the study, 61 patients between the ages of 14 to 73 years (mean age 44) diagnosed with IDPL on ultrasound (US) examination between the years 2020 and 2021 were included. The B-Mode US findings (shape, margins, size, echo pattern, and accompanying ductal dilatation), SMI vascular index (SMIvi), E-mean, and SWE-ratio values were recorded.

RESULTS

There was a statistically significant difference between malignant (n = 14) and benign (n = 47) groups in terms of symptoms (P = .005), size (P = .042), shape (P = .002), margins (P =  .001), echogenicity (P = .023), microcalcifications (P = .009), SMIvi (P = .031), E-mean (P < .005), and SWE-ratio (P = .007). According to receiver operating characteristic (ROC) curve analysis, sensitivity, specificity, accuracy, area under the curve (AUC), positive predictive values (PPV), and negative predictive values (NPV) were 57.1%, 87.2%, 80%, 0.722, 57.1%, 87.2% for US; 71.4%, 49%, 55.7%, 0.692, 30.3%, 85.7% for SMIvi; 85.7%, 71%, 74%, 0.864, 46%, 94.3% for E-mean, and 50%, 75.4%, 83%, 0.707, 91.5%, and 50% for SWE-ratio, respectively. Best results were obtained when SMI and SWE values were used together, achieving a sensitivity, specificity, accuracy, AUC, PPD, NPD of 78.6%, 93.6%, 93.4%, 0.872, 91.7%, and 93.9%, respectively.

CONCLUSIONS

The SMI and SWE examinations are successful in the differentiation of benign and malignant intraductal lesions. They complement each other and contribute to B-mode US in managing IDPLs especially when used together. Our study is the first to compare the quantitative data of SWE and SMI in the differentiation of IDPLs.

The diagnostic value of contrast-enhanced ultrasound and superb microvascular imaging in differentiating benign from malignant solid breast lesions: A systematic review and meta-analysis

OBJECTIVE

To investigate the added value of contrast-enhanced ultrasound (CEUS) and superb microvascular imaging (SMI) to the conventional ultrasound (US) in the diagnosis of breast lesions.

METHODS

PubMed, EMBASE, Web of Science, Chinese national knowledge infrastructure databases, Chinese biomedical literature databases, and Wanfang were searched for relevant studies from November 2015 to November 2021. The quality of the included studies was evaluated using the Quality Assessment of Diagnostic Studies (QUADAS) tool. Meta-Disc version 1.4 was used to calculate sensitivity (SEN), specificity (SPE), positive likelihood ratio (LR +), negative likelihood ratio (LR-), area under curve (AUC), and diagnostic odds ratio (DOR). Meta-regression analysis was performed using STATA 16.0 software to compare the diagnostic accuracy of the two techniques.

RESULTS

In the five studies included, 530 patients were eligible for this meta-analysis. For SMI, the pooled SEN and SPE were 0.75 (95% confidence interval [CI]: 0.69-0.91) and 0.88 (95% CI: 0.83-0.91), respectively, LR + was 5.75 (95% CI: 4.26-7.78), LR- was 0.29 (95% CI: 0.23-0.36), DOR was 21.42 (95% CI, 13.61-33.73), and AUC was 0.8871. For CEUS, the pooled SEN and SPE were 0.87 (95% CI: 0.82-0.91) and 0.86 (95% CI: 0.82-0.89), respectively, LR + was 5.92 (95% CI: 4.21-8.33), LR- was 0.16 (95% CI: 0.11-0.25), DOR was 38.27 (95% CI: 18.73-78.17), and AUC was 0.9210.

CONCLUSIONS

Adding CEUS and (or) SMI to conventional US could improve its diagnostic performance in differentiating benign from malignant solid breast lesions.

An Innovative Ultrasound Technique for Early Detection of Kidney Dysfunction: Superb Microvascular Imaging as a Reference Standard

Background: Superb microvascular imaging (SMI) is an innovative ultrasound image processing technique that provides greater detail and better visualization of small branching vessels. We assume that SMI will provide sufficient information regarding the severity of chronic kidney disease (CKD) and reflecting histological changes. Aims: The aims was to assess the capabilities of SMI imaging regarding the early detection of kidney dysfunction and renal fibrosis in comparison to the reference standard renal biopsy for the early diagnosis of kidney fibrosis. Methods: SMI was performed in patients (n = 52) with CKD stage 2–5, where some of them underwent biopsy proven CKD and fibrosis as part of the diagnosis. In addition, biochemical tests were performed, including kidney function tests, urine collection for proteinuria, and the estimation of GFR by MDRD or CKD-EPI eGFR in CKD patients and healthy controls (n = 17). All subjects underwent SMI, where vascularity is expressed as the SMI index (a low index reflects low vascularity/fibrosis and vice versa). Results: The SMI vascular index was significantly lower in CKD patients as compared with healthy controls (72.2 ± 12.9 vs. 49.9 ± 16.7%, p < 0.01). Notably, a moderate correlation between the SMI index and eGFR was found among the CKD patients (r = 0.56, p < 0.001). Similarly, a strong correlation was found between SCr and the SMI index of the diseased subjects (r = −0.54, p < 0.001). In patients who underwent renal biopsy, the SMI index corresponded with the histological alterations and CKD staging. Conclusions: This study demonstrated that SMI imaging may be utilized in CKD patients of various stages for the evaluation of chronic renal morphological changes and for differentiation between CKD grades.

Quantitative analysis of vascularity for thyroid nodules on ultrasound using superb microvascular imaging: Can nodular vascularity differentiate between malignant and benign thyroid nodules?

This study aimed to investigate the utility of adding superb microvascular imaging (SMI) to B-mode ultrasound (US) for distinguishing between benign and malignant thyroid nodules and evaluate the usefulness of SMI quantification of nodular vascularity for diagnosing thyroid cancer.The malignancy likelihood was scored for 3 datasets before versus after additional color Doppler imaging or SMI using 4-scale visual analysis (i.e., B-mode US alone, B-mode US + color Doppler image, and B-mode US + SMI). Further, the SMI pixel count was measured in the region of interest, including the whole nodule, on the longitudinal view. It was compared between benign and malignant nodules and analyzed according to the US patterns of thyroid nodules based on the Korean thyroid imaging reporting and data system. We calculated the area under the receiver operating characteristic curve values, sensitivities, and specificities.There was no significant difference in the area under the receiver operating characteristic curve values among B-mode, B-mode + color Doppler, and B-mode + SMI. However, the SMI pixel count was significantly higher in malignant thyroid nodules than in benign ones. The optimal cut-off value for the SMI pixel count for predicting malignant thyroid nodules obtained using a receiver operating characteristic curve was 17 (40.54% in sensitivity, 91.3% in specificity). Analysis based on the US pattern of thyroid nodules revealed significant differences in the nodules with low-to-intermediate suspicious US features between malignant and benign nodules.Quantification analysis of vascularity using SMI can differentiate malignant thyroid nodules from benign ones.

Multimodal ultrasound parameters aided carotid plaque risk stratification in patients with asymptomatic carotid stenosis

BACKGROUND

Risk stratification of asymptomatic carotid plaque remains an issue in stroke prevention in clinical practice.

PURPOSE

To investigate whether a multimodal ultrasound (MMU) model would help plaque risk stratification in patients with asymptomatic carotid stenosis.

MATERIAL AND METHODS

A prospective study was conducted of symptomatic and asymptomatic patients with > 50% proximal internal carotid artery (ICA) stenosis. All patients underwent MMU examination. Multivariable regression analyses were performed to identify parameters associated with ischemic vascular events (IVE). These parameters were used to develop a scoring nomogram to assess the probability of IVE. We elaborated the diagnostic performance of the MMU nomogram using receiver operating characteristic (ROC) curves.

RESULTS

From December 2018 to December 2019, 98 patients (75 men, mean age 67 ± 8 years) were included; 50 were symptomatic and 48 were asymptomatic. Multivariable regression analyses revealed that plaque surface morphology (PSM) (odds ratio [OR] 2.99, 95% confidence interval [CI] 1.26-7.12, P = 0.013), intraplaque neovascularization (IPN) grades (OR 3.23, 95% CI 1.77-5.89, P<0.001), and carotid stenosis degree (CSD) (OR 4.12, 95% CI 1.47-11.55, P = 0.007) were independently associated with IVE. For the nomogram, the area under the ROC curve was 0.85 (95% CI 0.77-0.92) and the Hosmer-Lemeshow test P value was 0.822.

CONCLUSIONS

In patients with proximal ICA > 50%, PSM, IPN grades, and CSD were independent variables associated with IVE. The MMU nomogram provided favorable value to risk stratification of IVE. Future large-scale studies with long-term follow-up are needed to validate these findings.

Comparison of Preoperative and Postoperative Testicular Elasticity and Vascularity in Pediatric Patients With Inguinal Hernia

OBJECTIVES

Testicular complications after inguinal hernia (IH) operations can be overlooked because they are difficult to diagnose, but usually have a long-term effect. This study evaluates the effects of IH on preoperative and postoperative testicular elasticity and vascularity in children with unilateral hernias, examined using the superb microvascular imaging (SMI) and shear wave elastography (SWE) modalities.

METHODS

Forty-four male children with unilateral indirect IHs were included. Quantitative SMI and SWE examinations of the testicles were performed on the herniated and intact sides, both preoperatively and at 1, 3, and 6 months postoperatively. The SMI and SWE values of the testicles were compared between the herniated and intact sides, as well as with the opposite testicle.

RESULTS

Preoperative vascular index (VI) values were lower on the herniated side than on the intact side. Furthermore, preoperative kPa and m/s values were higher on the herniated side than on the intact side. In follow-up examinations performed at 6 months postoperatively, there was no equalization of kPa or m/s values, although VI values were equalized on both sides.

CONCLUSIONS

Testicular vascularization secondary to mechanical compression in testicles on the herniated side increased significantly in the postoperative period, and reached a level similar to that of the contralateral side. Mean SWE values decreased in testicles on the herniated side, but were not equal with those of contralateral testicles. Preoperative and postoperative evaluation of testicles using SMI and SWE is important for detecting possible advanced testicular complications in children with IH.

Assessment of optic nerve vascularity in healthy eyes using superb microvascular imaging: a preliminary study

BACKGROUND

Changes in optic nerve vascularity are observed in many diseases. Superb microvascular imaging (SMI) has the potential to become the method of choice for detecting microvasculature in the optic nerves.

PURPOSE

To evaluate optic nerve vascularity in healthy individuals through power Doppler sonography (PDUS) and SMI.

MATERIAL AND METHODS

Twenty-seven healthy patients with 54 eyes were prospectively evaluated. The duration of the examination for optic nerve vascularity lasted until the posterior ciliary artery blood supply was observed in PDUS and SMI. The visibility of vascularity, as well as the ratio of the vascular structures to the optic nerves (vascular index [VI]), was evaluated.

RESULTS

Fifty-four eyes were evaluated from a total of 27 patients (mean age = 49.0 ± 19.42 years). The VI value for the right optic nerve was 29.58 ± 4.00 while for the left optic nerve, it was 31.21 ± 3.52. Vascularity was clearly observed in both eyes (n = 54) in all 27 cases in the evaluation performed with the SMI technique. However, with the power Doppler examination, vascular flow was not observed in 14 right eyes and in 10 left eyes within the specified timeframe.

CONCLUSION

The results indicate that imaging of vascular structures can be done faster and better with SMI than PDUS examination. The normal VI values may provide important information about the blood supply of the optic nerve, which is of relevance in orbital pathologies and many systemic conditions.

Detection of Carotid Atherosclerotic Intraplaque Neovascularization Using Superb Microvascular Imaging: A Meta-Analysis

OBJECTIVES

Although superb microvascular imaging (SMI) (Toshiba/Canon, Tokyo, Japan) has enabled routine characterization of intraplaque neovascularization (IPN) features in patients with carotid stenosis, no reports have been published on the multicenter and large sample size research in this aspect. The efficacy of SMI in detecting carotid IPN has not been concluded. This study aimed to assess the efficacy of SMI comparing with contrast-enhanced carotid ultrasonography (CEUS) in the detection of carotid IPN or pathologic evaluations of IPN correlated with a history of stroke or transient ischemic attack (TIA).

METHODS

Web of Science, Cochrane Library, PubMed, Embase, and Scopus were searched up to August 2020 to identify peer-reviewed human studies on the diagnostic accuracy of SMI in detecting IPN. For the selected study, the correlation coefficient R and Kappa index between SMI and CEUS in detecting IPN were calculated. The correlation coefficient R between SMI in identifying IPN and pathologic evaluations of IPN and the odds ratio of IPN detected by SMI and history of stroke or TIA were also extracted. The subgroup analysis was performed to indicate the source of heterogeneity.

RESULTS

Our search identified 11 reports enrolling a total of 605 carotid stenosis patients. Carotid IPN detected by SMI was significantly correlated with which detected by CEUS (R, 0.89; 95% CI, 0.80-0.94; P = .00, and Kappa index, 0.73; 95% CI, 0.67-0.80; P = .00). Notably, a significant correlation was observed in SMI in detecting IPN and pathologic evaluations of IPN (R, 0.52; 95% CI, 0.40-0.62; P = .00). The odds ratio of IPN detected by SMI and history of stroke or TIA was pooled summary with statistical significance (OR, 3.33; 95% CI, 1.78-6.23; P = .00). In subgroup analysis, lower heterogeneity was associated with the degree of carotid stenosis, patients from which country, and types of equipment.

CONCLUSIONS

SMI and CEUS display an excellent agreement in detecting carotid IPN. IPN detected by SMI shows high consistency with pathologic evaluations of IPN. Individuals with carotid IPN are more likely to develop stroke or TIA than those without carotid IPN.

The Diagnostic Value of Superb Microvascular Imaging in Prediction of Uterine Artery Embolization Treatment Response in Uterine Leiomyomas

OBJECTIVES

We aimed to determine if superb microvascular imaging (SMI) can predict response to uterine artery embolization (UAE) as compared with power Doppler ultrasound.

METHODS

The blood flow and the volume of the dominant leiomyoma was evaluated by power Doppler ultrasonography (PDUS) and SMI 1 day before and 3 months after the UAE procedure. SMI and PDUS blood flow were classified to 4 grades of vascularity. The change in fibroid volume in Grades 0-2 (hypovascular group) was compared to the hypervascular Grade 3 group.

RESULTS

Twenty-eight women (mean age, 40.9 years; range, 33-53 years) were examined with PDUS and SMI before and 3 months after UAE. The volume reduction was statistically significantly higher hypervascular group (P < .05). When we accept 30% or more volume reduction as a good response to UAE, the positive predictive value, negative predictive value, sensitivity, specificity, and accuracy of SMI were 100, 64, 73.6, 100, and 82.1%, respectively. There was excellent agreement between the two blinded observers in SMI measurements.

CONCLUSIONS

SMI, with its high reproducibility, provides further microvessel information than PDUS in uterine fibroids. It may be a useful tool in prediction of response to UAE treatment and improve counseling and patient selection for UAE versus medical or surgical treatment options.

Relationship Between Serum Lipid Profiles and Carotid Intraplaque Neovascularization in a High-Stroke-Risk Population: A Cross-Sectional Study in China

Background

Evidence of the association between serum lipid profiles and intraplaque neovascularization (IPN) is still limited. We aimed to study the value of a novel Doppler method, superb microvascular imaging, in correlating serum lipid profiles and evidence of IPN in a population with a high risk of stroke.

Methods and Results

A community‐based cross‐sectional study was conducted in Beijing, China. Residents (aged ≥40 years) underwent questionnaire interviews, physical examinations, and laboratory testing in 2018 and 2019. Subjects with a high risk of stroke were then selected. Standard carotid ultrasound and carotid plaque superb microvascular imaging examinations were then performed on the high–stroke‐risk participants. Logistic regression was used to evaluate the relationship between serum lipid profiles and carotid plaque IPN. Overall, a total of 250 individuals (mean age, 67.20±8.12 years; 66.4% men) met the study inclusion criteria. Superb microvascular imaging revealed carotid plaque IPN in 96 subjects (38.4%). Subjects with IPN were more likely to be current smokers (34.0% versus 46.9%, P=0.046), and their identified carotid plaques were much thicker (2.35±0.63 mm versus 2.75±0.80 mm, P=0.001). Serum lipids, including total cholesterol, non–high‐density lipoprotein cholesterol, and low‐density lipoprotein cholesterol were positively associated with the presence of IPN (4.33±1.00 mmol/L versus 4.79±1.12 mmol/L, P=0.001; 2.96±0.92 mmol/L versus 3.40±1.01 mmol/L, P=0.001; 2.18±0.76 mmol/L versus 2.46±0.80 mmol/L, P=0.005, respectively), and after adjustment for other confounders, the positive relationship remained significant. Furthermore, non–high‐density lipoprotein cholesterol (odds ratio, 2.62 [95% CI, 1.35–5.06]) was significantly associated with the presence of carotid plaque IPN even after adjusting for low‐density lipoprotein cholesterol.

Conclusions

Total cholesterol, non–high‐density lipoprotein cholesterol, and low‐density lipoprotein cholesterol were positively associated with the presence of carotid IPN in a Chinese high–stroke‐risk population. Further prospective studies should be conducted to better understand how much finding IPN adds to current stroke prediction tools.

Infrared Thermography and Ultrasonography of the Hands in Rheumatoid Arthritis Patients

Ultrasonography (US) and power Doppler US (PDUS) are used worldwide for diagnosing rheumatoid arthritis (RA). Superb microvascular imaging (SMI) is a good tool for evaluating inflammatory activity. Thermal imaging is a noncontact, noninvasive procedure using skin temperature measurement. We report a case wherein the thermal and ultrasound images of the hand are compared and evaluated for inflammatory activity in patients with RA. Case: US imaging of the left hand of a 75-year-old woman with RA revealed a hypoechoic lesion of the left wrist joint. PDUS and SMI evaluated blood flow according to the blood flow at Grade 2. The temperature of the hypoechoic lesion with high blood flow was higher than that of the same location on the opposite side. This study shows that combining thermal and blood flow images may be useful for detecting inflammatory activity levels in RA patients.

The place of B-mode ultrasonography, shear-wave elastography, and superb microvascular imaging in the pre-diagnosis of androgenetic alopecia

PURPOSE

Androgenetic alopecia (AGA) is the most common cause of hair loss in males. Physical examination and history are the most important examinations in diagnosis of the disease. As yet, there is no diagnostic method to be able to determine which individuals will develop AGA. Shear-wave elastography (SWE) is a novel diagnostic tool, which can evaluate tissue stiffness. Superb microvascular imaging (SMI) can determine low flow in microvessels. The aim of the current study was to determine whether or not AGA would develop in individuals with normal hair and a family history of AGA using B-mode US, SMI, and SWE.

METHODS

The study included 26 patients clinically diagnosed with AGA and a control group of 26 volunteers.

RESULTS

Thickness with the distance from the epidermis to the calvarium (ECD) on the hairline and cranial subcutaneous tissue thickness (CSTD) were determined to be statistically significantly thinner in the AGA group than in the control group (p < 0.0001). For the differentiation of the AGA patients, the cutoff value was determined to be 5.5 mm for ECD and 4.05 mm for CSTD. The cranial epidermis-dermis (CED) stiffness values both as meter/second (m/s) and kilopascals (kPa) were statistically significantly lower in the AGA patients than in the control group (p < 0.0001). The cutoff values were 6.075 as m/s and 104.4 as kPa.

CONCLUSIONS

The results of this study demonstrated that differentiation could be made of individuals before the development of AGA from normal healthy individuals with CSTD measurement on B-mode US and CED stiffness measurement on SWE.

The Promising Role of a Superb Microvascular Imaging Technique in the Evaluation of Raynaud's Syndrome in Systemic Sclerosis: Theory and Practical Challenges

In recent years, a novel Doppler ultrasonography (US) modality—superb microvascular imaging (SMI)—has been presented as a reliable method to evaluate small vessel blood flow with minimised motion artefacts. In this review, we present the challenges of incorporating SMI in daily practice with detailed and comparable US images of a fingertip. The main focus of this paper is the discussion of all tested US techniques, artefacts, and practical challenges for evaluating Raynaud’s syndrome in systemic sclerosis. Despite a few reports on SMI use in assessing nailfold capillaries, there is still a need for more evidence of its value and possibilities for its standardisation.

Quantitative analysis of distal femoral epiphysis blood supply in healthy newborns and infants with superb microvascular imaging

BACKGROUND/AIM

To determine the blood supply of the distal femoral epiphysis (DFE) using superb microvascular imaging in newborns and infants, and to investigate the correlation with ossification center (OC) length, gender and age.

MATERIALS AND METHODS

A total of 140 cases were evaluated in this study. The cases were divided into 2 groups of less than 90 days and over than 90 days. Cartilage blood supply was measured with vascularity index (%) (VI).

RESULTS

The mean OC length and median VI values were measured as 10.20±3.72 mm and 0.80% (0.58-1.50) for boys and 10.03±3.36 mm and 0.70 % (0.30-1.40) for girls, respectively. There was no significant difference in OC length and VI between genders. The mean OC length in Group II was significantly higher than in Group I (12.14±3.14 vs 8.09± 2.64) (p < 0.001). The median VI in Group I was higher than the cases in Group II (1.40% vs 0.40%) (p<0.001). There were positive correlations between age and OC length (r=0.716), negative correlations between age and VI (r=-0.822), and between VI and OC length (r=-0.657).

CONCLUSION

Quantitative reference values for DFE blood supply and OC length can guide the diagnosis and follow-up of many skeletal diseases.

The Role of Superb Microvascular Imaging and Shear Wave Elastography in Differentiation of Thyroid Nodules from Intrathyroidal Ectopic Thymus in Children

BACKGROUND

Ectopic thymus could be located intrathyroidal, therefore fine ultrasound details are useful for this differentiation.

AIM

To investigate differences in stiffness and vascularity properties among thyroid nodules and intrathyroidal ectopic thymus (IET) by obtaining quantitative data in children.

PATIENTS AND METHODS

Twenty-seven thyroid nodules and 20 IET in children were evaluated in terms of vascularity index (VI) via superb microvascular imaging (SMI) and stiffness by shear wave elastography (SWE). Differences in the volume, VI, and SWE parameters of the lesions were assessed by using the Mann-Whitney U test. Association of the age, lesion volume, SWE, and VI parameters was investigated by using Spearman's correlation analysis. The optimal cut-off values for stiffness and vascularity in the differentiation of nodules from IET were calculated with ROC analysis.

RESULTS

The median (range) age of the participants with thyroid nodules and IET were 15.6 (10-18) years and 8.8 (3-14) years, respectively. The medians (range) VI of the IET and thyroid nodules were 4.7 (0.2-16) % and 23.8 (7.5-40)%, respectively. The median SWE values were 7.6 (4.4-9.5) kPa and 15.58 (8.5-23.4) kPa for IET and nodules, respectively. There have been highly significant differences among medians of volume, SWE, and VI values of the lesions. Significant positive correlations were found between VI and SWE parameters (p=0.001, r=0.64), and volume with VI (p=0.018, r=0.34) and SWE (p:0.001, r= 0.5). The diagnostic accuracies were 93%, 91% with the cut-off values as 9.2 kPa, 13% for the SWE and SMI, respectively. IETs were found to be less vascular and less stiff than thyroid nodules.

CONCLUSIONS

IETs could be easily and confidently differentiated from nodules using SWE and SMI quantifications. This discrimination prompts the reduction of unnecessary interventional procedures.

Superb microvascular imaging for detecting carpal tunnel syndrome compared with power Doppler ultrasonography: A protocol for systematic review and meta-analysis

BACKGROUND

Sonography enhances diagnostic accuracy by the detection of the epineural or intraneuronal blood flow.[1-4] Power Doppler ultrasonography (PDUS) in carpal tunnel syndrome (CTS) has been previously studied and shown to be valid and reliable for grading the intraneural flow.[3,4] However, superb microvascular imaging (SMI) represents a new era in diagnostic sonography, and this new technology enables accurate visualization of vascular structures with intensive clutter suppression to provide flow signals for large to small vessels, and it presents these data at high frame rates.[5-7] Studies suggested that SMI is more sensitive in demonstrating blood flow in the diagnosis of CTS compared with PDUS.[7] In order to gain clarity, a meta-analysis to systematically review and synthesize relevant data on the evaluating intraneural blood flow of the median nerve (MN) using SMI and PDUS was undertaken.

METHODS

We will search PubMed, Web of Science, Cochrane Library, and Chinese biomedical databases from their inceptions to the December 31, 2020, without language restrictions. Two authors will independently carry out searching literature records, scanning titles and abstracts, full texts, collecting data, and assessing risk of bias. Review Manager 5.2 and Stata 14.0 software will be used for data analysis.

RESULTS

This systematic review will investigate whether superb microvascular imaging is more sensitive to display the blood flow in the MN with CTS than PDUS.

CONCLUSION

Its findings will provide strong evidence for the feasibility of superb microvascular imaging on the detection of the neovascularization of the MN with CTS.

SYSTEMATIC REVIEW REGISTRATION

INPLASY202110018.