Clinical Applications of Superb Microvascular Imaging in the Liver, Breast, Thyroid, Skeletal Muscle, and Carotid Plaques

Preoperative Role of Superb Microvascular Imaging and Shear-Wave Elastography for Prediction of Axillary Lymph Node Metastasis in Patients With Breast Cancer

ABSTRACT

This study aims to evaluate the role of shearwave elastography (SWE) and superb microvascular imaging (SMI) for preoperative prediction of axillary lymph node metastasis (ALNM) in patients with breast cancer. In a cohort of 214 women with breast cancer, B-Mode ultrasonography (US), SMIvascular-index (SMIvi), and SWE (E-mean, E-ratio) values were recorded before tru-cut biopsy. Axillary fine-needle aspiration biopsy (FNAB) and sentinel lymph node sampling results were collected. Imaging findings and histopathological data were statistically compared. Receiver operating characteristic curve analysis was used to evaluate diagnostic performance. Reverse stepwise logistical regression analysis was conducted. Although ALNM was negative in 111 cases, it was positive in 103 patients. Axillary lymph node metastasis (+) group had larger size ( P < 0.001), higher vascularization (SMIvi: 8.0 ± 6.0 versus 5.0 ± 4.3, P < 0.001), and higher elasticity value (E-mean: 129 ± 31 kPa versus 117.3 ± 40 kPa, P = 0.014). Axillary lymph node metastasis was observed statistically more frequently in Her-2 positive cases ( P = 0.005). There was no significant difference between other B-mode US findings ( P > 0.05), SMI Adler ( P = 0.878), and E-ratio ( P = 0.212). The most appropriate cutoff value for the prediction of ALNM was 23.5 mm for size, 3.8 for SMIvi, and 138.5 kPa for E-mean. The most sensitive (77%) method was the SMIvi measurement, while the most specific (86%) finding was Her-2 positivity. The combined model (being Her-2 positive, >23.5 cm, and >3.8 SMIvi) increased the specificity (78%), PPV (71%), and accuracy (68%). Although the increased size is a previously studied parameter in predicting the risk of ALNM, Her-2 and data obtained by SWE, and SMI can be used to assist conventional US.

Evaluation of the thyroid gland vascularity during pregnancy using 2-dimensional color Superb Microvascular İmaging vascularization index technique

PURPOSE

We aimed to investigate maternal thyroid parenchymal vascularity with 2-dimensional color superb microvascular imaging vascularization index (2D-cSMIVI) levels and thyroid gland volume in the first, second and third trimesters.

METHODS

This longitudinal prospective study was carried out with participants selected from 30 healthy asymptomatic pregnant women. Ultrasonography (US) for the thyroid gland was performed in each trimester. The vascularization index (VI) values obtained by manually drawing the contours of the thyroid parenchyma in the longutidinal plane, using the free region of interest (ROI) with 2DcSMIVI mode. VI values obtained in each trimester, thyroid hormone levels (TSH, T3, T4) and thyroid volumes were compared.

RESULTS

We have detected that thyroid gland vascularity increased significantly as pregnancy progresses. The mean VI values of thyroid gland in third trimester were significantly higher than first and second trimester (p < 0.001), and the mean VI values of the thyroid gland in the second trimester were significantly higher than first trimester (p < 0.001). During pregnancy, we detected the increase in VI values, TSH levels and thyroid gland volumes.

CONCLUSION

Maternal thyroid gland gray scale findings, parenchymal vascularization, thyroid volumes should be evaluated routinely for the healthy fetal development. 2D-cSMIVI method allows us to evaluate vascularization with quantitative numerical values objectively. We have detected that the VI values and volume of the thyroid gland increases as pregnancy progresses. In the complex situation of pregnancy process, the thyroid gland can be evaluated quantitatively with SMI method effectively.

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.

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.

Prediction of papillary thyroid metastases to the central compartment: proposal of a model taking into consideration other thyroid conditions

Objective

To construct risk prediction models for cervical lymph node metastasis (CLNM) of papillary thyroid carcinoma (PTC) under different thyroid disease backgrounds and to analyze and compare risk factors among different groups.

Methods

This retrospective study included 518 patients with PTC that was pathologically confirmed post-operatively from January 2021 to November 2021. Demographic, ultrasound and pathological data were recorded. Univariate and multivariate logistic regression analyses were performed to identify factors associated with CLNM in the whole patient cohort and in patients grouped according to diagnoses of Hashimoto's thyroiditis (HT), nodular goiter (NG), and no background disease. Prediction models were constructed for each group, and their performances were compared.

Results

Analysis of the whole PTC patient cohort identified NG as independently associated with CLNM. The independent risk factors for patients with no background disease were the maximum thyroid nodule diameter and American College of Radiology Thyroid Imaging Reporting & Data System score; those for patients with HT were the maximum thyroid nodule diameter, ACR TI-RADS score, and multifocality; and those for patients with NG were the maximum thyroid nodule diameter, ACR TI-RADS score, multifocality and gender.

Conclusion

Background thyroid disease impacts CLNM in PTC patients, and risk factors for CLNM vary among PTC patients with different background diseases. Ultrasound is useful for diagnosing background thyroid disease, which can inform treatment planning. Different prediction models are recommended for PTC cases with different thyroid diseases.

Current and future utility of ultrasound imaging in upper extremity musculoskeletal rehabilitation: A scoping review

STUDY DESIGN

This study was a scoping review.

BACKGROUND

Continued advances in musculoskeletal sonography technology and access have increased the feasibility of point-of-care use to support day-to-day clinical care and decision-making. Sonography can help improve therapeutic outcomes in upper extremity (UE) rehabilitation by enabling clinicians to visualize underlying structures during treatment.

PURPOSE OF THE STUDY

This study aimed to (1) evaluate the growth, range, extent, and composition of sonography literature supporting UE rehabilitation; (2) identify trends, gaps, and opportunities with regard to anatomic areas and diagnoses examined and ultrasound techniques used; and (3) evaluate potential research and practice utility.

METHODS

Searches were completed in PubMed, CINAHL, SPORTDiscus, PsycINFO, and BIOSIS. We included data-driven articles using ultrasound imaging for upper extremity structures in rehabilitation-related conditions. Articles directly applicable to UE rehabilitation were labeled direct articles, while those requiring translation were labeled indirect articles. Articles were further categorized by ultrasound imaging purpose. Article content between the two groups was descriptively compared, and direct articles underwent an evaluation of evidence levels and narrative synthesis to explore potential clinical utility.

RESULTS

Average publication rates for the final included articles (n = 337) steadily increased. Indirect articles (n = 288) used sonography to explore condition etiology, assess measurement properties, inform medical procedure choice, and grade condition severity. Direct articles (n = 49) used sonography to assess outcomes, inform clinical reasoning, and aid intervention delivery. Acute UE conditions and emerging sonography technology were rarely examined, while tendon, muscle, and soft tissue conditions and grayscale imaging were common. Rheumatic and peripheral nerve conditions and Doppler imaging were more prevalent in indirect than direct articles. Among reported sonography service providers, there was a high proportion of nonradiologist clinicians.

CONCLUSION

Sonography literature for UE rehabilitation demonstrates potential utility in evaluating outcomes, informing clinical reasoning, and assisting intervention delivery. A large peripheral knowledge base provides opportunities for clinical applications; however, further research is needed to determine clinical efficacy and impact for specific applications.

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.

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.

New microvascular ultrasound techniques: abdominal applications

Microvascular ultrasound (MVUS) is a new ultrasound technique that allows the detection of slow-velocity flow, providing the visualization of the blood flow in small vessels without the need of intravenous contrast agent administration. This technology has been integrated in the most recent ultrasound equipment and applied for the assessment of vascularization. Compared to conventional color Doppler and power Doppler imaging, MVUS provides higher capability to detect intralesional flow. A growing number of studies explored the potential applications in hepatobiliary, genitourinary, and vascular pathologies. Different flow patterns can be observed in hepatic and renal focal lesions providing information on tumor vascularity and improving the differential diagnosis. This article aims to provide a detailed review on the current evidences and applications of MVUS in abdominal imaging.

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.

Diagnostic Performance of Superb Microvascular Imaging in Differentiating Benign and Malignant Axillary Lymph Nodes

ABSTRACT

The aim was to evaluate the effectiveness of superb microvascular imaging (SMI) in axillary lymph nodes (LNs).Benign and malignant LNs diagnosed via histopathological examination constituted the study subgroups. In addition to grayscale findings for morphological evaluation, vascular patterns and appearance of internal vessels were analyzed by both power Doppler ultrasound (PDUS) and SMI. The number of vascular branches was counted, and a vascularity index (VI) was calculated by SMI.Fifty-two LNs with suspicious findings in terms of metastasis (33 malignant and 19 benign) were evaluated. Diagnostic accuracy according to vascular patterns was 82% for PDUS and 92% for SMI. In the presence of asymmetric cortical thickening, there was a significant difference between benign and malignant LNs in the number of vascular branches of both thin and thick cortical sides ( P < 0.01). Mean VI was significantly higher in the malignant group ( P < 0.05). In differentiating malignancy, when a cutoff VI value was set to 9%, sensitivity was 69.7%, and specificity was 63.2%.Evaluating the vascularity of axillary LNs by SMI is a useful tool in determining the potential of axillary metastasis, especially in the absence of typical sonographic findings. Superb microvascular imaging can beneficially be used to select the most suspicious LN and suspicious area of the LN to sample.

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.

Intraoperative shear-wave elastography and superb microvascular imaging contribute to the glioma grading

BACKGROUND

To explore the diagnostic value and feasibility of shear wave elastography and superb microvascular imaging in the grading diagnosis of glioma intraoperatively.

MATERIALS AND METHODS

Forty-nine patients with glioma were included in this study. B-mode ultrasonography, Young's modulus in shear-wave elastography (SWE) and vascular architecture in superb microvascular imaging(SMI) of tumor tissue and peritumoral tissue were analyzed. Receiver operating characteristic(ROC) curve analysis was used to evaluate the diagnostic effect of SWE. Logistic regression model was used to calculate the prediction probability of HGG diagnosis.

RESULTS

Compared with LGG, HGG was often characterized by peritumoral edema in B mode (P < 0.05). There was a significant difference in Young's modulus between HGG and LGG; the diagnostic threshold of HGG and LGG was 13.05 kPa, the sensitivity was 78.3%, and the specificity was 76.9%. The vascular architectures of the tumor tissue and peritumoral tissues of HGG and LGG were significantly different (P < 0.05). The vascular architectures of peritumoral tissue in HGG often characterized by distorted blood flow signals surrounding the tumor (14/26,53.8%); in the tumor tissue, HGG often presents as dilated and bent vessels(19/26,73.1%). The elasticity value of SWE and the tumor vascular architectures of SMI were correlated with the diagnosis of HGG.

CONCLUSION

Intraoperative ultrasound (ioUS), especially SWE, and SMI are beneficial for the differentiation of HGG and LGG and may help optimize clinical surgical procedures.

Construction and Validation of a Predictive Nomogram Based on Ultrasound for Lymph Node Metastasis of Papillary Thyroid Carcinoma in the Cervical Central Region

ABSTRACT

To establish and validate a nomogram for predicting lymph node metastasis (LNM) of papillary thyroid carcinoma (PTC) in the cervical central region. This retrospective study included 287 PTC patients with 309 nodules treated from December 2018 to May 2020 at our hospital. The cohort was divided randomly into a training set and a testing set according to a 7:3 ratio. The training set contained 216 nodules, and the testing set contained 93 nodules. The nomogram was developed using the training set, and the data of the testing set were used to validate the performance of nomogram. The predictive accuracy and discriminative ability of the nomogram were determined by concordance index (C-index) and calibration curve. The study showed multifocality, thyroid lesion size, and American College of Radiology Thyroid Imaging, Reporting and Data System (TI-RADS) score were significantly independently associated with LNM in the cervical central region. In the testing set, the calibration curve showed that the nomogram had good discrimination with a C-index of 0.775 (95% confidence interval, 0.680-0.869) and adequate calibration ( P = 0.808). By decision curve analysis and clinical impact curve analysis, the nomogram was shown to have a satisfactory net benefit between thresholds of 0.40 and 0.75. The nomogram can be used for predicting LNM of PTC in the cervical central region and may provide valuable guidance for planning the surgical treatment of PTC patients.

Use of new microcirculation software allows the demonstration of dermis vascularization

AIMS

Current ultrasound (US) Doppler techniques cannot demonstrate the vascularization of the dermis. The purpose of this study was to investigate whether the new Superb Vascular Imaging (SMI) and Microvascular Flow (MV-Flow) techniques improve the detection of normal dermis vessels. SMI and MV-Flow were compared side-by-side to conventional power-Doppler (PD) imaging.

METHODS

By using US, 50 healthy volunteers were evaluated at level of five body areas: forehead, forearm, palm, buttock, and thigh. Two off-site operators evaluated the images to assess the difference between SMI and PD imaging and between MV-Flow and PD imaging in terms of dermis flow amount. A 0-3 scoring system was adopted.

RESULTS

SMI scored grade 0 in 0% of body areas, grade 1 in 58%, grade 2 in 33%, and grade 3 in 9%. In comparison with SMI, PD scored grade 0 in 38% of body areas, grade 1 in 56%, grade 2 in 6%, and grade 3 in 0%. MV-Flow scored grade 0 in 0% of body areas, grade 1 in 52%, grade 2 in 43%, and grade 3 in 6%. Comparted to MV-Flow, PD scored grade 0 in 53% of body areas, grade 1 in 34%, grade 2 in 13%, and grade 3 in 0%. The difference in terms of sensitivity was statistically significant for all the body areas investigated.

CONCLUSIONS

We found both SMI and MV-Flow to be superior to PD imaging and capable to demonstrate normal vascularization of the dermis.

The Preliminary Application of Simultaneous Display of Contrast-Enhanced Ultrasound and Micro-Flow Imaging Technology in the Diagnosis of Hepatic Tumors

OBJECTIVES

To evaluate the value of simultaneous display of contrast-enhanced ultrasound and micro-flow imaging technology (CEUS-MFI) in intra-tumoral vessel detection and hepatic tumor diagnosis.

METHODS

A total of 82 patients with 82 focal liver lesions were enrolled in this study. Each patient received ultrasound exams including color Doppler flow imaging (CDFI), micro-flow imaging (MFI), contrast-enhanced ultrasound (CEUS), and CEUS-MFI with a Philips EPIQ7 ultrasound imaging system. The intra-tumoral vessels detected by CDFI, MFI, and CEUS-MFI were compared, respectively. The accuracy and confidence of using CEUS and CEUS-MFI in diagnosing hepatic tumors were also compared.

RESULTS

CEUS-MFI was capable of detecting more hepatic intra-tumoral vessels than MFI (P = .000) and CDFI (P = .000). Compared with CEUS, CEUS-MFI improved the diagnostic accuracy of hepatic lesions (P = .009). Particularly, among the correctly diagnosed hepatic lesions, the number of cases where radiologists diagnosed with great confidence was increased from 88.4% (61/69) with CEUS only to 92.4% (73/79) with CEUS-MFI (P = .041).

CONCLUSIONS

CEUS-MFI is sensitive in detecting hepatic intra-tumoral vessels and can improve the accuracy and confidence of radiologists in diagnosing hepatic lesions.

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.

High-resolution Doppler ultrasound in systemic sclerosis: Analysis of digital arteries and nailfold microvasculature using 18-5 MHz and 33-9 MHz probes

INTRODUCTION

Newly developed Doppler techniques enable the sampling of slow vascular flows and the extrapolation of spectral parameters in distal arterioles. The aim of this study was to investigate the role of spectral analysis performed by means of ultra-high frequency ultrasound (US) in the evaluation of the peripheral vascular bed of systemic sclerosis (SSc) patients.

METHODS

Both hands of 33 patients affected by diffuse cutaneous SSc and 34 volunteers were evaluated with a US machine equipped with 33-9 MHz and 18-5 MHz transducers. Proximal resistive index and the peak systolic velocity (pRI and pPSV, respectively), were calculated at the level of the second interdigital artery. The distal resistive index (dRI) was calculated at the level of a nailfold arteriole of the third finger. All SSc patients had been previously divided into 4 subgroups according to their nailfold videocapillaroscopic (NVC) patterns following accepted criteria.

RESULTS

SSc patients showed a significantly slower systolic velocity at the level of the second interdigital artery (pPSV [SD] = 8.38 [3] cm/s vs pPSV [SD] = 11.14 [4.5] cm/s; P = .005) and a higher dRI (dRI [SD] = 0.65 (0.14) vs dRI [SD] = 0.57 [0.11); P = .0115). No differences were found between the pRI values measured in the SSc patients and those of the controls (pRI [SD] = 0.76 [0.11] vs pRI [SD] = 0.73 [0.12]; P = .359]. The subgroup analysis did not show any significant difference when pPSV, pRI and dRI were compared among NVC morphological patterns.

CONCLUSION

High-resolution Doppler analysis of digital distal arterioles may disclose subtle abnormalities in the downstream microvasculature of SSc patients that could be missed when the examination is performed at a more proximal level and/or using lower Doppler frequencies.

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.

Intraoperative Evaluation of Brain-Tumor Microvascularization through MicroV IOUS: A Protocol for Image Acquisition and Analysis of Radiomic Features

Microvascular Doppler (MicroV) is a new-generation Doppler technique developed by Esaote (Esaote s.p.a., Genova, Italy), which is able to visualize small and low-flow vessels through a suppression of interfering signals. MicroV uses advanced filters that are able to differentiate tissue artifacts from low-speed blood flows; by exploiting the space-time coherence information, these filters can selectively suppress tissue components, preserving the signal coming from the microvascular flow. This technique is clinically applied to the study of the vascularization of parenchymatous lesions, often with better diagnostic accuracy than color/power Doppler techniques. The aim of this paper is to develop a reproducible protocol for the recording and collection of MicroV intraoperative ultrasound images by the use of a capable intraoperative ultrasound machine and post-processing aimed at evaluation of brain-tumor microvascularization through the analysis of radiomic features. The proposed protocol has been internally validated on eight patients and will be firstly applied to patients affected by WHO grade IV astrocytoma (glioblastoma-GBM) candidates for craniotomy and lesion removal. In a further stage, it will be generally applied to patients with primary or metastatic brain tumors. IOUS is performed before durotomy. Tumor microvascularization is evaluated using the MicroV Doppler technique and IOUS images are recorded, stored, and post-processed. IOUS images are remotely stored on the BraTIoUS database, which will promote international cooperation and multicentric analysis. Processed images and texture radiomic features are analyzed post-operatively using ImageJ, a free scientific image-analysis software based on the Sun-Java platform. Post-processing protocol is further described in-depth. The study of tumor microvascularization through advanced IOUS techniques such as MicroV could represent, in the future, a non-invasive and real-time method for intraoperative predictive evaluation of the tumor features. This evaluation could finally result in a deeper knowledge of brain-tumor behavior and in the on-going adaptation of the surgery with the improvement of surgical outcomes.

Case series of mobile structures detected vividly by using superb microvascular imaging

Background

Superb microvascular imaging (SMI) is a new imaging technique that can reveal low-velocity blood flow without use of a contrast agent. SMI is based on an original algorithm and effectively removes tissue motion artifacts (clutter motion) from the background, thereby preserving visibility of low-velocity blood flow. SMI is expected to be useful for the evaluation of heart diseases, as well as blood vessels.

Case summary

Here, we report three cases in which a mobile structure in the heart or a blood vessel was detected easily by strong enhancement on SMI. In the heart, the entire mass was strongly enhanced by colour-SMI and had the appearance of 'a fire ball'. In the abdominal aorta and carotid artery, SMI captured a strongly enhanced echo image of a mass and revealed hyperechoic mobile plaque. It was hard to detect with the conventional echocardiography.

Discussion

It is important to detect mobile intravascular and intracardiac structures as they are risk factors of thrombosis. Echo images are often strongly affected by the skill of the examiner, the patient's body habitus, and the presence of intestinal gas; thus, it is often difficult to detect a small mass with conventional echocardiography. With the use of SMI, even small mobile structures can be displayed at high intensity in comparison with the surrounding blood flow. Therefore, the non-invasive SMI was useful for the detection of mobile intravascular and intracardiac structures. Our findings of the current report may lead to new developments in SMI for imaging in the cardiac region.

Adaptive and Robust Vessel Quantification in Contrast-Free Ultrafast Ultrasound Microvessel Imaging

The morphological features of vasculature in diseased tissue differ significantly from those in normal tissue. Therefore, vasculature quantification is crucial for disease diagnosis and staging. Ultrasound microvessel imaging (UMI) with ultrafast ultrasound acquisitions has been determined to have potential in clinical applications given its superior sensitivity in blood flow detection. However, the presence of spatial-dependent noise caused by a low imaging signal-to-noise ratio and incoherent clutter artifacts caused by moving hyperechoic scatterers degrades the performance of UMI and the reliability of vascular quantification. To tackle these issues, we proposed an improved UMI technique along with an adaptive vessel segmentation workflow for robust vessel identification and vascular feature quantification. A previously proposed sub-aperture cross-correlation technique and a normalized cross-correlation technique were applied to equalize the spatially dependent noise level and suppress the incoherent clutter artifact. A square operator and non-local means filter were then used to better separate the blood flow signal from residual background noise. On the de-noised ultrasound microvessel image, an automatic and adaptive vessel segmentation method was developed based on the different spatial patterns of blood flow signal and background noise. The proposed workflow was applied to a CIRS phantom, to a Doppler flow phantom and to an inflammatory bowel, kidney and liver, to validate its feasibility. Results revealed that automatic adaptive, and robust vessel identification performance can be achieved using the proposed method without the subjectivity caused by radiologists/operators.

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.

Superb Microvascular Imaging (SMI) Compared with Color Doppler Ultrasound for the Assessment of Hepatic Artery in Pediatric Liver Transplants: A Feasibility Study

(1) Background: Despite progression in surgical techniques and immunological treatments, hepatic artery (HA) thrombosis and stenosis still develop as an early or late liver transplant (LT) complication. We aimed to compare superb microvascular imaging (SMI) with conventional Doppler imaging (CDI) in the assessment of HA in a cohort of pediatric patients undergoing follow-up ultrasound (US) for LT. (2) Methods: This prospective, observational study included 73 pediatric LT recipients (median age, 7 years; IQR, 5.8 years; 35 females) who underwent US during LT follow-up from March to December 2019. For each examination, CDI and SMI were separately assessed in terms of HA visibility and spectral waveform morphology (SWM). The former was scored based on HA discrimination from the blooming signal of the surrounding vessels, as follows: 0, not visible; 1, majority course hardly distinguishable; and 2, majority course clearly distinguishable. The latter was scored on a two-point scale: 0, combined venous and arterial SWM, and 1, pure arterial SWM. The patient’s overall score was finally calculated by adding the two individual scores. (3) Results: Both the absolute scores and frequency of overall scores equal to 3 (maximum global score) were higher using SMI compared with CDI. The median overall score was 3 for SMI and 2 for CDI (p = 0.011; IQR = 1). An overall score equal to 3 was obtained in 74% and 49.3% of the study population using SMI and CDI, respectively (p = 0.002). This was attributable to a better score in HA visibility (p = 0.007). (4) Conclusions: SMI has shown promise for assessing HA in pediatric LT recipients, possibly serving as a complementary non-invasive tool of CDI in everyday practice.

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.

Ultrasonography of Superficial Soft-Tissue Masses: Society of Radiologists in Ultrasound Consensus Conference Statement

The Society of Radiologists in Ultrasound convened a panel of specialists from radiology, orthopedic surgery, and pathology to arrive at a consensus regarding the management of superficial soft-tissue masses imaged with US. The recommendations in this statement are based on analysis of current literature and common practice strategies. This statement reviews and illustrates the US features of common superficial soft-tissue lesions that may manifest as a soft-tissue mass and suggests guidelines for subsequent management.

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.

Comparison of superb microvascular imaging (SMI) quantified with ImageJ to quantified contrast-enhanced ultrasound (qCEUS) in liver metastases-a pilot study

BACKGROUND

The aim of the study was to compare methods for the assessment of vascularisation of liver metastases (LM) between superb microvascular imaging (SMI), contrast-enhanced ultrasound, and microvascular density (MVD).

METHODS

SMI results were quantified as the vascularisation quotient (VQ), based on a grey-scale analysis with ImageJ image software. Those results were compared to contrast-enhanced ultrasonography (CEUS) values, calculated with VueBox^®. MVD was measured with an anti-CD34 antibody.

RESULTS

This study included 13 patients with LM. The VQ showed a strong correlation with the quantified parameters of contrast-enhanced ultrasound. The parameters of quantified contrast-enhanced ultrasound compared with quantified SMI showed the following statistical correlations: peak enhancement (PE), in arbitrary unit (a.u.) (r=0.72104, P=0.0054), PE in Decibel (dB) (r=0.65918, P=0.00141), Wash-in- Area Under the Curve (WiAUC) in a.u. (r=0.63604, P=0.00194), Wash-in Perfusion-Index (WiPI) in a.u. (r=0.73337, P=0.0043), Wash-in Perfusion-Index (WiPI) in dB (r=0.65642, P=0.0194), Wash-in-Rate (WiR) in a.u. (r=0.7304, P=0.0036) and Wash-in-Rate (WiR) in dB (r=0.82897, P=0.0005).

CONCLUSIONS

Comparison of the two methods, SMI and contrast-enhanced ultrasound (CEUS), for quantitative assessment of vascularisation of LM showed good correlation. The contrast-independent Doppler technique SMI can qualitatively assess the vascularisation of LM.

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.

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.

Seeing the unseen with superb microvascular imaging: Ultrasound depiction of normal dermis vessels

PURPOSE

Current color- and power-Doppler techniques cannot demonstrate vascularization of the dermis. Aim of this prospective study was to investigate whether the new superb vascular imaging (SMI) technique improves the ultrasound (US) depiction of dermis vessels in healthy volunteers. SMI was compared side-by-side to conventional power-Doppler (PD) imaging.

METHODS

Thirty adult subjects (18 men and 12 women, mean age 45 years old) were evaluated with US at level of five body areas: forehead, forearm, palm, buttock, and thigh. The vascular index (VI) was employed to objectively quantify the difference between SMI and PD imaging in terms of dermis flow amount.

RESULTS

Forehead VI was higher for SMI than for PD in 93% of cases, forearm VI was higher for SMI than for PD in 97% of cases, palm VI was higher for SMI than for PD in 87% of cases, buttock VI was higher for SMI than for PD in 100% of cases, thigh VI was higher for SMI than for PD in 100% of cases. SMI-detected vascular signals in 100% of the body areas. PD failed to show any flow signals from the forehead in 23% of cases, forearm in 37% of cases, palm in 33% of cases, buttock in 47% of cases, and thigh in 50% of cases.

CONCLUSION

SMI can demonstrate normal dermis vascularization whereas conventional PD cannot. SMI is a sensitive and promising technique in the study of dermis abnormalities, particularly when quantifying the disease activity is important.

Ultrasound Image Optimization for the Interventional Radiologist

Understanding the basics and nuances of the functionality of ultrasound (US) equipment and of its various knobs and modes will enable the interventional radiologist to acquire higher quality US images. This, in turn will potentially allow US-guided procedures to be performed safely, and with greater operator confidence, and may also allow certain procedures to be performed with US instead of CT or fluoroscopic guidance. In this article, we review the practical aspects of US image optimization for the interventional radiologist, including equipment and transducer selection, depth, focal zone and gain setting adjustment, as well as special considerations for imaging the obese patient. Color Doppler image optimization and recent developments in ultrasound imaging are briefly discussed.

Vascular Imaging Techniques to Diagnose and Monitor Patients with Takayasu Arteritis: A Review of the Literature

Takayasu arteritis (TA) is a large vessel vasculitis that causes stenosis, occlusion, and sometimes the aneurysm of the aorta and its major branches. TA often occurs in young women, and because the symptoms are not obvious in the early stages of the disease, diagnosis is difficult and often delayed. In approximately 10% to 20% of patients, TA is reportedly complicated by ischemic stroke or transient ischemic attack. It is important to diagnose TA early and provide appropriate treatment to prevent complications from stroke. Diagnostic imaging techniques to visualize arterial stenosis are widely used in clinical practice. Even if no signs of cerebrovascular events are present at the time of the most recent evaluation of patients with TA, follow-up vascular imaging is important to monitor disease progression and changes in the cerebrovascular risk. However, the optimal imaging technique for monitoring of TA has not been established. Therefore, the purpose of this review is to describe newly available evidence on the usefulness of conventional imaging modalities (digital subtraction angiography, computed tomography angiography, magnetic resonance imaging/angiography, duplex ultrasound, and positron emission tomography) and novel imaging modalities (optical coherence tomography, infrared thermography, contrast-enhanced ultrasonography, and superb microvascular imaging) in the diagnosis and monitoring of TA.

Potential for novel imaging techniques to monitor early disease progression in connective tissue disease vasculopathy

Vasculopathy associated with connective tissue diseases (CTD) has diverse clinical presentations and complex underlying pathology. Existing imaging techniques remain inadequate for assessing vasculopathy in CTD, particularly in earlier stages of pathogenesis. Novel imaging techniques, such as optical coherence tomography, near-infrared spectroscopy and superb microvascular imaging, demonstrate potential in monitoring disease progression at earlier stages prior to systemic complications.

Application of Superb Microvascular Imaging in the Diagnosis of Vascular Erectile Dysfunction

To compare the difference between superb microvascular imaging (SMI) and color doppler flow imaging (CDFI) on vascular grading and blood flow display rate of the penile cavernous artery of vascular erectile dysfunction (ED), and to evaluate the length of time to obtain blood flow spectrum. 68 patients with ED were preformed for the examination of SMI and CDFI. The difference between the two techniques on vascular grading and blood flow display rate were compared. Hemodynamic parameters, namely peak systolic velocity (PSV), end diastolic velocity (EDV), and resistant index (RI) and the length of time obtained blood flow spectrum were compared. SMI was more sensitive to assess vascular grading and blood flow display rate than CDFI (P < 0.05). Hemodynamic parameters (PSV, EDV, and RI) measured by SMI and CDFI were well correlated (r = 0.981, P < 0.001; r = 0.879, P < 0.001; r = 0.937, P < 0.001). The duration of time necessary obtained the spectrums of grade 3 and grade 4 blood flow was shorter than that of grade 1 and grade 2, and SMI was comparatively shorter than CDFI (P < 0.05). In conclusion, SMI detected the blood flow of the penile cavernous artery better and maked the examination time shorter than CDFI, which can be considered as a more effective technique to diagnose vascular ED.

Multidisciplinary diagnostic dilemma in differentiating Madelung’s disease — the value of superb microvascular imaging technique: A case report

BACKGROUND

Madelung’s disease, also known as multiple symmetrical lipomatosis, is a rare, underrecognized disorder of fat metabolism that results in unusual accumulation of subcutaneous fat deposits around the neck, shoulders, upper arms, trunk, hips, and upper thighs. Our case demonstrates the importance of differential diagnosis and the value of a superb microvascular imaging technique for suspecting and confirming Madelung’s disease. Timely diagnosis and alcohol abstinence could prevent the progression of growing fatty masses and prevent surgery.

CASE SUMMARY

A 62-year-old male was admitted to the Rheumatology center complaining of symmetric subcutaneous tumors in the area of the parotid and submandibular salivary glands, small soft masses in the occiput and upper third of the forearm, rashes on calves. A high titer of rheumatoid factor and low concentrations of serum complements were detected. The high-end ultrasound and magnetic resonance imaging examinations of all affected areas of the soft tissues showed predominantly adipose tissue (lipomas) without suspicion of liposarcoma. The biopsy from the small salivary gland revealed no pathology. After evaluating the patient’s clinical presentation (symmetrical lipomatosis, cirrhosis, gynecomastia, anemia, hyperuricemia), Madelung’s disease, type I, along with the psoriatic rash and psoriatic arthritis and secondary liver cirrhosis were established.

CONCLUSION

Madelung’s disease consists of many co-occurring disorders imitating and overlapping with other conditions. Ultrasonography is the first choice for suspecting and confirming symmetrical lipomatosis.

Lymphadenopathy after the Anti-COVID-19 Vaccine: Multiparametric Ultrasound Findings

Background: Post-anti-COVID-19 vaccine lymphadenopathy has recently been described in the literature. In this study, we investigated the multiparametric US findings of patients with post-vaccine lymphadenopathy and compared these findings among different anti-COVID-19 vaccines. Methods: We retrospectively evaluated 24 patients who underwent US between January and May 2021 due to post-anti-COVID-19 lymphadenopathy. The presence, size, location, number, morphology, cortex-hilum, superb microvascular imaging (SMI) and elastosonography of lymph nodes were assessed. Descriptive statistics were calculated and differences among anti-COVID-19 vaccines were analyzed using the Kruskal-Wallis test. A p-value ≤ 0.05 was considered statistically significant. Results: Sixty-six nodes were assessed. They were axillary (mean 1.6 cm ± 0.16) in 11 patients (45.8%) and supraclavicular (mean 0.9 cm ± 0.19) in 13 patients (54.2%). In 20 patients (83.3%), the number of nodes was ≤3. Prevalent US features included oval morphology (18, 75%), asymmetric cortex with hilum evidence (9, 37.5%), central and peripheral vascular signals (12, 50%) at SMI and elastosonography patterns similar to the surrounding tissue (15, 71.4%). No significant differences among the three anti-COVID-19 vaccines were observed (p > 0.05). Conclusions: Anti-COVID-19 vaccines may present lymphadenopathy with "worrisome" US features regarding size, shape, morphology, cortex-hilum, SMI and elastosonography. An awareness of the patient's history and US findings may help in the early recognition of this clinical scenario and in the appropriate selection of patients for a short-term US follow-up.

SWE and SMI ultrasound techniques for monitoring needling treatment of ankylosing spondylitis: study protocol for a single-blinded randomized controlled trial

Background

Ankylosing spondylitis (AS) is a high-incidence disease in young men that interferes with patients’ physical and mental wellbeing and overall quality of life (QoL). It is often accompanied by arthralgia, stiffness, and limited lumbar flexibility. Acupuncture is safe and effective for reducing the symptoms of AS, but the underlying mechanisms by which it does so are not fully understood. Therefore, to objectively assess acupuncture efficacy, which is critical for patients making informed decisions about appropriate treatments, we will use shear-wave elastography (SWE) and superb microvascular imaging (SMI) ultrasound techniques to evaluate elasticity of lumbar paraspinal muscles and blood flow to the sacroiliac joint (SIJ) in AS.

Methods

We will recruit a total of 60 participants diagnosed with AS and 30 healthy subjects. Participants will be randomly allocated 1:1 to either an acupuncture group or a sham control acupuncture group. Primary-outcome measures will be musculoskeletal ultrasound, Ankylosing Spondylitis Quality of Life Scale (ASQoL), Bath Ankylosing Spondylitis Metrology Index (BASMI), and the Visual Analogue Scale (VAS) for pain. Secondary outcome measures will be the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Function Index (BASFI), and Fatigue Scale-14 (FS-14). We will monitor the effect of acupuncture or sham acupuncture on blood flow and SIJ inflammation using SMI, lumbar-muscle stiffness using SWE and the lumbar paraspinal-muscle cross-sectional area (CSA) using a two-dimensional (2D) grayscale imaging. QoL, physical function, and fatigue will be assessed using an evaluation scale or questionnaire developed for this study, with outcomes measured by the ASQoL, BASMI, BASDAI, BASFI, and FS-14. Healthy subjects will not receive acupuncture but undergo only musculoskeletal ultrasound at baseline. Acupuncture and sham control acupuncture interventions will be conducted for 30 min, 2–3 times/week for 12 weeks. Musculoskeletal ultrasound will be conducted at baseline and post-intervention, while other outcomes will be measured at baseline, 6 weeks, and post-intervention. The statistician, outcome assessor, and participants will be blinded to treatment allocation.

Discussion

The results of this single-blinded, randomized trial with sham controls could help demonstrate the efficacy of acupuncture and clarify whether musculoskeletal ultrasound could be used to evaluate AS.

Trial registration

ClinicalTrials.gov ChiCTR2000031476. Registered 3 April 2020.

Clinical Applications of Superb Microvascular Imaging in the Superficial Tissues and Organs: A Systematic Review

Superb microvascular imaging (SMI) is an innovative Doppler technique for vascular examination. It uses an intelligent algorithm that efficiently separates low-speed flow signals from motion artifacts so that it can assess microvessels and the vessel distribution in detail. This article reviews the clinical applications of SMI in the disorders of superficial tissues and organs including thyroid nodules, breast tumors and lymph node diseases etc. More information of diseases that are closely associated with angiogenesis can be shown by SMI than other noninvasive examinations. Although some limitations exist, this safe and convenient technique is becoming acceptable and would play a more important role in disease diagnosis and therapeutic responses evaluation.

An advanced ultrasound application used to assess peripheral vascular diseases: superb microvascular imaging

Over the past several years, a novel ultrasound imaging modality termed superb microvascular imaging (SMI) has enabled visualization of microvessels. SMI ultrasound studies of peripheral artery diseases have significantly extended our knowledge of tissue microcirculation and the arterial microenvironments of atherosclerotic lesions. We here present an overview of current knowledge on the utility of SMI assessment of vascular diseases and highlight certain peripheral microcirculation disorders for which SMI is particularly valuable. The evidence indicates that SMI can detect intraplaque neovascularization and usefully assess carotid plaque vulnerability; vascularization of the carotid arterial wall detected by SMI is a potential marker of disease activity in patients with Takayasu arteritis; SMI reveals the foot microcirculation and yields a quantitative vascular index (in line with the angiosome concept); and, SMI may serve as an auxiliary diagnostic modality for hereditary hemorrhagic telangiectasia and Raynaud syndrome. In general, microcirculatory evaluation by SMI is an attractive field for future research on therapeutic strategies for peripheral vascular diseases.

Evaluation of parenchymal vascularity of the thyroid gland with vascularization index by color superb microvascular imaging in patients with Graves' disease

Aim of the study

To determine the parenchymal vascularity of the thyroid gland with color superb microvascular imaging in patients with Graves’ disease, and compare the vascularization index values with healthy subjects.

Materials and methods

The thyroid glands of 37 patients whose laboratory and clinical findings were consistent with Graves’ disease, and 40 asymptomatic subjects with normal laboratory values, were examined using color superb microvascular imaging. Measurements of the vascularization index were performed with a free region of interest which was drawn along the outer margin of the gland on the color superb microvascular imaging mode. The vascularization index values obtained in the Graves’ disease and control groups were compared. A correlation analysis was performed between the vascularization index values and laboratory and grayscale US parameters.

Results

The median vascularization index value of the thyroid parenchyma in patients with Graves’ disease was significantly higher than in the asymptomatic group [median (min–max); 12 (2.3–32.1) vs 5.04 (1.1–10.8), p <0.001]. When the cutoff value of the vascularization index is determined as 6.3, Graves’ disease can be diagnosed with 83.8% sensitivity and 70% specificity.

Conclusions

The vascularization index obtained with color superb microvascular imaging can be a quantitative indicator of parenchymal vascularity in the diagnosis of Graves’ disease, and serve as a supportive tool.

Added Value of the Vascular Index on Superb Microvascular Imaging for the Evaluation of Breast Masses: Comparison With Grayscale Ultrasound

OBJECTIVES

To evaluate the value of the vascular index (VI) on Superb Microvascular Imaging (SMI; Canon Medical Systems Corporation, Tokyo, Japan) in comparison with grayscale ultrasound (US) alone for assessing breast masses.

METHODS

We evaluated a total of 70 breast masses (36 malignant and 34 benign lesions) in 70 consecutive patients using grayscale US and SMI. Two breast radiologists analyzed grayscale US alone and the combination of grayscale US and SMI. They also measured the VI based on SMI. The diagnostic performance of grayscale US alone and the combination of grayscale US and SMI was compared. The VI was compared between benign and malignant masses, and the optimal cutoff value was determined. In addition, the interobserver agreement in imaging analyses and the VI was assessed.

RESULTS

The interobserver agreements in imaging analyses and the VI were almost perfect. The VI of malignant breast masses was significantly higher than that of benign lesions (P < .001). The optimal cutoff value of the VI for differentiating between malignant and benign breast masses was 2.95, with sensitivity of 86.1% and specificity of 91.2%. The diagnostic performance values of grayscale US alone and the combination of grayscale US and SMI were 0.824 and 0.912, respectively, for reader 1 (P = .028) and 0.795 and 0.853 for reader 2 (P = .101).

CONCLUSIONS

The VI on SMI was significantly higher for malignant breast masses than for benign lesions, with high interobserver agreement. Our study suggests that the combination of grayscale US and SMI with the VI could improve the characterization of breast masses.

Diagnostic accuracy of ultrasound superb microvascular imaging for parotid tumors: A protocol for systematic review and meta-analysis

BACKGROUND

As a novel ultrasound technique, superb microvascular imaging (SMI) can quickly, simply, and noninvasively study the microvascular distribution in the tumor and evaluate the microvascular perfusion. Studies suggested that SMI is helpful for the differentiation between benign and malignant parotid tumors. However, the results of these studies have been contradictory. Therefore, the present meta-analysis aimed at determining the accuracy of SMI in the differential diagnosis between benign and malignant parotid tumors.

METHODS

We will search PubMed, Web of Science, Cochrane Library, and Chinese biomedical databases from their inceptions to September 30, 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 Stata14.0 software will be used for data analysis.

RESULTS

This systematic review will determine the accuracy of SMI in the differential diagnosis between benign and malignant parotid tumors.

CONCLUSION

Its findings will provide helpful evidence for the accuracy of SMI in the differential diagnosis between benign and malignant parotid tumors.

SYSTEMATIC REVIEW REGISTRATION

INPLASY2020100093.

Imaging based flowchart for gallbladder polyp evaluation

BACKGROUND

Preoperative differentiation between neoplastic and nonneoplastic gallbladder polyps, and the subsequent indication for cholecystectomy remains a clinical dilemma. The current 1 cm size threshold for neoplasia is unspecific. The aim of this study was to improve diagnostic work-up for gallbladder polyps using sonographic and MRI characteristics of neoplastic and nonneoplastic polyps.

METHODS

A prospective, exploratory study including patients undergoing cholecystectomy for gallbladder polyp(s) was conducted. Patients underwent targeted transabdominal ultrasound (TAUS) and MRI. Outcomes were sensitivity and specificity for polyp diagnosis, and the radiological characteristics of neoplastic and nonneoplastic polyp types. Histopathology after cholecystectomy was used as reference standard.

RESULTS

Histopathology demonstrated gallbladder polyps in 20/27 patients (74%): 14 cholesterol polyps, three adenomyomatosis, two adenomas and one gastric heterotopia. Sensitivity of polyp identification were 72% (routine TAUS) and 86% (targeted TAUS and MRI). Both adenomas were identified as neoplastic on targeted TAUS and MRI. Sonographic presentation as multiple, pedunculated polyps, either heterogeneous or with hyperechoic foci, or as single polyps containing cysts were limited to nonneoplastic polyps. On MRI hyperintense polyps on T1-weighted image were cholesterol polyps. An adenoma with high-grade dysplasia showed foci of decreased ADC values. We propose a checklist for polyp evaluation by targeted TAUS and a flowchart for radiological work-up of gallbladder polyps.

CONCLUSIONS

The presented checklist and flowchart could aid diagnostic work-up for gallbladder polyps compared to current routine ultrasound, by elimination of nonneoplastic polyps and ultimately improve treatment decision for patients with gallbladder polyps.

Advanced Musculoskeletal Ultrasound Techniques: What Are the Applications?

OBJECTIVE. The purpose of this article is to cover technical advances in musculo-skeletal ultrasound from the viewpoint of the radiologist. CONCLUSION. Among the advances in musculoskeletal ultrasound that we highlight the use of ultrahigh-frequency transducers to visualize ever-finer anatomic detail, the expanding practical clinical applications for microvascular imaging, and the use of elastography to predict function and, possibly, healing potential.