Comparison of superb micro-vascular imaging (SMI) and conventional Doppler imaging techniques for evaluating testicular blood flow

Assessment of quantitative microflow Vascular Index in testicular cancer

PURPOSE

Ultrasound (US) is the primary imaging modality when a testicular tumor is suspected. Superb microvascular imaging (SMI) is a novel, highly sensitive Doppler technique that allows quantification of flow signals by determination of the Vascular Index (VI). The aim of the present study is to investigate the diagnostic significance of the SMI-derived VI in normal testicular tissue and testicular cancer.

METHODS

This retrospective analysis included patients who underwent testicular US in our department from 2018 to 2022. Inclusion criteria were: i) sufficient image quality of the stored images, ii) US with standardized SMI-default setting (colour gain of 44 ± 5), iii) patient age ≥ 18 years, and iv) normal testicular findings or testicular tumor with histopathological workup. US examinations were performed as part of clinical routine using a high-end ultrasound system (Aplio i800/i900, Canon Medical Systems Corporation, Tochigi, Japan). Statistical analysis included Chi-square test and Mann-Whitney U tests and receiver operating characteristic (ROC) curve analysis.

RESULTS

A total of 62 patients (31 each with normal findings and testicular tumors) were included. The VI differed statistically significantly (p < 0.001) between normal testis (median 2.5 %) and testicular tumors (median 17.4 %). Like vascular patterns (p < 0.001), the VI (p = 0.030) was shown to distinguish seminomas (median 14.8 %), non-seminomas (median 17.6 %) and lymphomas (median 34.5 %).

CONCLUSIONS

In conclusion, our study has shown the VI to be a quantitative tool that can add information for differentiating testicular tumor entities. While further confirmation in larger study populations is desirable, our results suggest that the VI may be a useful quantitative parameter.

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 Value of Superb Microvascular Imaging and Contrast-enhanced Ultrasound for the Evaluation of Neovascularization in Carotid Artery Plaques

OBJECTIVE

To compare the consistency between superb microvascular imaging (SMI) and contrast-enhanced ultrasound (CEUS) for the detection of neovascularization in carotid plaques of different thicknesses and to evaluate the applied value of these two methods for detecting neovascularization in carotid plaques in the clinic.

METHODS

A total of 45 patients with carotid artery plaques who were diagnosed in our hospital involving 76 hypoechoic plaques with a thickness ≥2.0 mm were selected. According to thickness, the plaques were divided into three groups: 2.0-2.5 mm, 2.5-3.0 mm and ≥3.0 mm. Each group underwent both SMI and CEUS, and two experienced sonographers (A and B) analyzed the ultrasound images to evaluate the neovascularization of carotid plaques. The amount of the neovascular signal was assessed using a semi-quantitative grading scale (vascularity grade: grade 0-3). SMI and CEUS were graded respectively according to the visual methods as follows: grade 0: no blood flow signal/enhancement within plaques; grade 1: a few blood flow signals/enhancement within plaques; grade 2: medium blood flow signals/enhancement within plaques; and grade 3: extensive blood flow signals/enhancement within plaques. Kappa consistency test was used to analyze the consistency of the grade of neovascularization in plaques between SMI with CEUS. Gamma rank correlation analysis was used to examine the correlation between neovascularization grade by SMI and CEUS in plaque and plaque thickness.

RESULTS

Of these patients, 14 had unilateral plaques and 31 had bilateral plaques. The two sonographers were highly consistent in terms of applying SMI and CEUS methods for diagnosing neovascularization in carotid plaques (Kappa values were 0.736 and 0.680>0). Consistency was found between SMI and CEUS by sonographers (sonographer A: Kappa=0.823; sonographer B: Kappa=0.842) in evaluating the neovascular grade in the carotid plaques. SMI and CEUS grades were positively correlated with plaque thickness (sonographer A: γ = 0.735 and 0.772; sonographer B: γ = 0.805 and 0.798).

CONCLUSION

Neovascularization in carotid plaques was successfully detected by SMI in a manner that concurred well with CEUS results. Our data indicate that both CEUS and SMI have high diagnostic value for assessing the neovascularization of plaques.

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.

Microvascular Flow Imaging: A State-of-the-Art Review of Clinical Use and Promise

Vascular imaging with color and power Doppler is a useful tool in the assessment of various disease processes. Assessment of blood flow, from infarction and ischemia to hyperemia, in organs, neoplasms, and vessels, is used in nearly every US investigation. Recent developments in this area are sensitive to small-vessel low velocity flow without use of intravenous contrast agents, known as microvascular flow imaging (MVFI). MVFI is more sensitive in detection of small vessels than color, power, and spectral Doppler, reducing the need for follow-up contrast-enhanced US (CEUS), CT, and MRI, except when arterial and venous wash-in and washout characteristics would be helpful in diagnosis. Varying clinical applications of MVFI are reviewed in adult and pediatric populations, including its technical underpinnings. MVFI shows promise in assessment of several conditions including benign and malignant lesions in the liver and kidney, acute pathologic abnormalities in the gallbladder and testes, and superficial lymph nodes. Future potential of MVFI in different conditions (eg, endovascular repair) is discussed. Finally, clinical cases in which MVFI correlated and potentially obviated additional CEUS, CT, or MRI are shown.

Multimodal ultrasound imaging: A method to improve the accuracy of diagnosing thyroid TI-RADS 4 nodules

Thyroid nodule is a common and frequently occurring disease in the neck in recent years, and ultrasound has become the preferred imaging diagnosis method for thyroid nodule due to its advantages of noninvasive, nonradiation, real-time, and repeatable. The thyroid imaging, reporting and data system (TI-RADS) classification standard scores suspicious nodules that are difficult to determine benign and malignant as grade 4, and further pathological puncture is recommended clinically, which may lead to a large number of unnecessary biopsies and operations. Including conventional ultrasound, ACR TI-RADS, shear wave elastography, super microvascular imaging, contrast enhanced ultrasound, "firefly," artificial intelligence, and multimodal ultrasound imaging used in combination. In order to identify the most clinically significant malignant tumors when reducing invasive operations. This article reviews the application and research progress of multimodal ultrasound imaging in the diagnosis of TI-RADS 4 thyroid nodules.

Response of human periodontal ligament to orthodontic force using superb microvascular imaging

INTRODUCTION

Remodeling of the periodontal ligament (PDL) during orthodontic tooth movement is closely related to the vascularity of the PDL, which has not been thoroughly investigated in humans. This study aimed to measure the width and vascular parameters of human PDL using superb microvascular imaging for the first time.

METHODS

Patients aged 18-25 years were selected for participation. The intervention was randomly allocated from the maxillary canines to the first molars on both sides using 50 g or 150 g of force. The width and vascular parameters of the PDL were measured using superb microvascular imaging at different time intervals (baseline, 30 minutes, and 1, 3, 7, and 14 days).

RESULTS

Before the intervention, the width of the PDL ranged from 0.14 to 0.25 mm, and the vascular index ranged from 9.40% to 13.54%. After applying orthodontic forces, the cervical and middle PDL widths increased. The vascular index decreased slightly in 30 minutes, decreased to a minimum value after 1 day, increased to the maximum in 3-7 days, and returned to baseline values in 14 days. The values of other vascular parameters showed similar trends.

CONCLUSIONS

The width and vascular parameters of the PDL changed slightly after force application, underwent changes in the period of reconstruction for 3-7 days, and eventually returned to baseline in 14 days.

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.

Usefulness of Real-Time Quantitative Microvascular Ultrasonography for Differentiation of Graves' Disease from Destructive Thyroiditis in Thyrotoxic Patients

BACKGROUND

Microvascular ultrasonography (MVUS) is a third-generation Doppler technique that was developed to increase sensitivity compared to conventional Doppler. The purpose of this study was to compare MVUS with conventional color Doppler (CD) and power Doppler (PD) imaging to distinguish Graves' disease (GD) from destructive thyroiditis (DT).

METHODS

This prospective study included 101 subjects (46 GDs, 47 DTs, and eight normal controls) from October 2020 to November 2021. All ultrasonography examinations were performed using microvascular flow technology (MV-Flow). The CD, PD, and MVUS images were semi-quantitatively graded according to blood flow patterns. On the MVUS images, vascularity indices (VIs), which were the ratio (%) of color pixels in the total grayscale pixels in a defined region of interest, were obtained automatically. Receiver operating characteristic curve analysis was performed to verify the diagnostic performance of MVUS. The interclass correlation coefficient and Cohen's kappa analysis were used to analyze the reliability of MVUS (ClinicalTrials.gov:NCT04879173).

RESULTS

The area under the curve (AUC) for CD, PD, MVUS, and MVUS-VI was 0.822, 0.844, 0.808, and 0.852 respectively. The optimal cutoff value of the MVUS-VI was 24.95% for distinguishing GD and DT with 87% sensitivity and 80.9% specificity. We found a significant positive correlation of MVUS-VI with thyrotropin receptor antibody (r=0.554) and with thyroid stimulating immunoglobulin bioassay (r=0.841). MVUS showed high intra- and inter-observer reliability from various statistical method.

CONCLUSION

In a real time and quantitative manner, MVUS-VI could be helpful to differentiate GD from thyroiditis in thyrotoxic patients, with less inter-observer variability.

Quantitative assessment of bladder wall vascularity index in children with acute cystitis using superb microvascular imaging

PURPOSE

The purpose of this study was to investigate the effectiveness of the vascularization index (VI) obtained using color superb microvascular imaging (cSMI) technique in assessment of the anterior urinary bladder wall in pediatric patients with acute cystitis (AC).

METHODS

The anterior bladder wall of 157 patients (age range 13-84 months, mean 43.62 ± 17.79 months) whose clinical and laboratory findings were proven of AC and 150 healthy asymptomatic participants (age range 13-84 months, mean 43.88 ± 18.11 months) with normal laboratory values were examined using cSMI. VI measurements were performed by manually drawing the contours of the anterior bladder wall using the free region of interest with 2-dimensional cSMI VI (2DcSMIVI) mode. The quantitative 2DcSMIVI values of the symptomatic group and the asymptomatic group were compared. The correlation between the 2DcSMIVI values and the anterior bladder wall thickness (BWT) were analyzed.

RESULTS

The mean 2DcSMIVI values of the BWT were significantly higher in symptomatic group when compared to the asymptomatic group (p<0.001). AC can be diagnosed with a 93% sensitivity, 92% specificity when 3.25% 2DcSMIVI designated as the cutoff value. There was a significant positive correlation between 2DcSMIVI values and BWT (p<0.001).

CONCLUSION

Two-dimensional cSMI VI can be used effectively in children as an imaging method in the diagnosis of AC.

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 Use of Transabdominal Ultrasound in Inflammatory Bowel Disease

Transabdominal ultrasound (TAUS) is useful in all aspects of lesion screening, monitoring activity, or treating/diagnosing any related complications of inflammatory bowel disease. Its ability to screen or diagnose complications is almost the same as that of other methods, such as CT or MRI. Moreover, its noninvasiveness makes it a first-line examination method. A TAUS image depicting ulcerative colitis will show large intestinal wall thickening that is continuous from the rectum, which is mainly due to mucosal layer thickening, while for Crohn’s disease, a TAUS image is characterized by a diversity in the areas affected, distribution, and layer structure. Indicators of activity monitoring include wall thickness, wall structure, and vascular tests that use Doppler ultrasound or contrast agents. While all of these have been reported to be useful, at this time, no single parameter has been established as superior to others; therefore, a comprehensive evaluation of these parameters is justified. In addition, evaluating the elasticity of lesions using elastography is particularly useful for distinguishing between fibrous and inflammatory stenoses. However, the lack of objectivity is the biggest drawback of using ultrasound. Standardizing and popularizing the ultrasound process will be necessary, including scanning methods, equipment settings, and image analysis.

EVAR Follow-Up with Ultrasound Superb Microvascular Imaging (SMI) Compared to CEUS and CT Angiography for Detection of Type II Endoleak

The aim of this study was to evaluate the usefulness of superb microvascular imaging (SMI) versus contrast-enhanced ultrasound (CEUS) and compared to computed tomography angiography (CTA) as a reference standard, for detection of type II endoleak during follow-up of endovascular abdominal aortic aneurysm repair (EVAR). Between April 2017 and September 2020, 122 patients underwent post-EVAR follow-up with CTA at 3 months and with ultrasound SMI and CEUS at 4 months from the EVAR procedure. Aneurysmal sac diameter and graft patency were evaluated; endoleaks were assessed and classified. Sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy were calculated both for SMI and CEUS and compared to CTA. Furthermore, the percentage of agreement and Cohen’s Kappa coefficient were calculated. CTA revealed 54 type II endoleaks. Ultrasound SMI and CEUS presented the same sensitivity (91.5%), specificity (100%), positive (100%), and negative (92.8%) predictive and accuracy (95.9%) value for detecting type II endoleak. The same percentage of agreement of 94.9% was found between SMI/CEUS, and CTA with a Cohen’s Kappa coefficient of 0.89. The diagnostic accuracy of SMI is comparable with CEUS in the identification of type II endoleaks after EVAR. Since SMI is less invasive, less expensive, and less time-consuming, this method may be considered to be a potential tool for monitoring patients after EVAR implantation.

Improved Detection of Gallbladder Perforation Using Ultrasound Small Vessel Slow Flow "Perfusion" Imaging

Gallbladder (GB) perforation is a potentially fatal cause of acute abdomen. Higher morbidity and mortality are associated with this entity due to delayed diagnosis and treatment. Ultrasound with color/power Doppler and contrast sonography can detect wall discontinuity; however, sometimes it can be subtle or unavailable. Small vessel slow flow "perfusion" imaging allows improved microvascular perfusion detection using different filters, which result in increased spatial resolution and vessel visualization. Noncontrast perfusion imaging was of immense clinical value in the diagnosis of GB perforation in the six cases presented here. To the best of our knowledge, this is the first case report describing efficacy of noncontrast "perfusion" imaging in detection of GB perforation.

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.

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.

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.

Comparison of the Balthazar score of acute pancreatitis between computed tomography and ultrasound in children: pitfalls of ultrasound in diagnosing and evaluating pancreatitis

PURPOSE

To demonstrate the utility of ultrasound for predicting the outcome of pancreatitis in pediatric patients using the Balthazar score.

METHODS

Twenty-four children diagnosed with pancreatitis, who underwent computed tomography (CT) followed by ultrasound within 24 h, were included. The Balthazar score was calculated using both modalities based on the appearance of the pancreas (score 0-4). The association between the Balthazar scores with CT and ultrasound was evaluated using single linear regression analysis. To evaluate the sonographic accuracy, the ultrasound severity index and findings were compared with those of CT. Presence or absence of abnormal pancreatic parenchymal change on ultrasound was compared to the presence or absence of pancreatic necrosis on CT. The CT and sonographic findings were evaluated in eight intra-abdominal segments.

RESULTS

The Balthazar scores yielded by CT (2.2 ± 1.1, range 0-4) and ultrasound (2.0 ± 1.1, range 0-4) showed a significantly strong correlation (r = 0.918, p < 0.001). The accuracy of ultrasound in determining the CT Balthazar scores was 91.7% (95% confidence interval 73.0-99.0%, 22/24 patients). In the two cases with pancreatic necrosis on CT, only one case was detected as abnormal pancreatic parenchymal change. Sonographic diagnostic accuracy in the pancreatic head was lower than that in the body and tail (accuracy of the pancreatic head, body, and tail enlargement/edema = 83.3%/75%, 100%/100%, and 100%/100%, respectively).

CONCLUSIONS

The total CT and ultrasound severity indices were significantly correlated. Ultrasound is a useful modality for evaluating not only the initial pancreatic condition but also the severity of pediatric pancreatitis.

Utility of 2-Dimensional Shear Wave Elastography for Assessment of the Bladder Wall in Children With Acute Cystitis

OBJECTIVES

The aim of this study was to investigate the efficacy of 2-dimensional (2D) shear wave elastography (SWE) in the diagnosis of acute cystitis (AC) in children.

METHODS

Between June 2019 and March 2020, 126 children with AC and 126 healthy participants were prospectively investigated by 2D SWE and B-mode ultrasound. Elastographic measurements were performed by drawing the contours of the posterior wall of the bladder between the ureter orifices using a free region of interest. The quantitative 2D SWE values of the patients and the healthy group were compared.

RESULTS

The mean 2D SWE values of the bladder wall were significantly higher in patients with AC compared to the healthy group (P = .001). On B-mode ultrasound imaging, the bladder wall thickness of patients with AC was higher than that in the healthy group (P = .001). On 2D SWE, when the cutoff value used was 9.25 kPa, the sensitivity, specificity, positive predictive value, and negative predictive value were 92.1%, 88.1%, 89.3%, and 92.6%, respectively, whereas when the cutoff value used was 1.72 m/s, the sensitivity, specificity, positive predictive value, and negative predictive value were 90.5%, 88.9%, 89.1%, and 90.7%. There was a statistically significant positive correlation between the 2D SWE values and wall thickness measurements (P < .001).

CONCLUSIONS

Two-dimensional SWE is a noninvasive, fast, and effective imaging method to evaluate the bladder wall in children with AC.

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.

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.

Comparison of testicular vascularity via superb microvascular imaging in varicocele patients with contralateral normal testis and healthy volunteers

PURPOSE

In this study, we aimed to determine vascular changes in the testes in patients with varicocele using the two-dimensional color superb microvascular imaging vascular index (2DcSMIVI) and compared them with those of the normal contralateral testes of the same patients as well as the normal testes of control subjects without varicocele.

METHODS

A total of 114 participants and 228 testes were included in the study. 63 patients with varicocele and 51 asymptomatic volunteers were included. In total, 70 testes with varicocele (group A), 56 normal contralateral testes (Group B), and 102 bilateral normal testes were classified (Group C). Participants' testicular volume and 2DcSMIVI values were obtained via superb microvascular imaging. Testes with varicocele were graded according to Sarteschi classification.

RESULTS

Statistically significant differences in mean testicular volume were observed among the three groups. The volume and 2DcSMIVI values of the varicocele side testes were significantly lower than those of groups B and C. Significant differences were also observed between Sarteschi grade and 2DcSMIVI values in group A.

CONCLUSION

We can determine impaired microcirculation of varicocele side testes quantitatively with the 2DcSMIVI technique, and obtained VI values can be used effectively in diagnosis and follow-up of the damage in testes. Our results show that 2DcSMIVI values can play a significant role in the evaluation of testicular blood flow as a predictive sign of testicular damage.

Evaluation of benign parotid gland tumors with superb microvascular imaging and shear wave elastography

Aim of the study: This study aimed to examine the role of superb microvascular imaging and shear wave elastography for the pre-surgical evaluation of common parotid tumors. Material and methods: This single-center prospective study included 37 patients with parotid gland lesions. After institutional review board approval, grayscale, shear wave elastography and superb microvascular imaging ultrasound examinations were performed prior to biopsy or operation. The diagnosis of the lesions was based on cytological/pathological evaluation after the ultrasound examinations. Pleomorphic adenomas and Warthin tumors were compared using the Mann–Whitney U test. A receiver operating characteristic curve analysis was performed to obtain a cut-off value. A multivariate regression analysis was carried out. Results: The mean age of the patients (11 female, 26 male) was 48.2 ± 18. The shear wave elastography parameters of the lesions were not significantly different between pleomorphic adenomas and Warthin tumors, while the vascular index obtained by using superb microvascular imaging was significantly different (p = 0.012). The mean vascular index was 2.9 ± 3.1 in pleomorphic adenomas, and 9.5 ± 9.5 in Warthin tumors. A cut-off value of 4.05 for the vascular index discriminated pleomorphic adenoma and Warthin tumors with 68% sensitivity and 72% specificity (the area under the curve was 0.768). Conclusion: Superb microvascular imaging is a novel ultrasound imaging technique which is useful for the discrimination of pleomorphic adenomas and Warthin tumors.

Testicular Torsion in the Emergency Room: A Review of Detection and Management Strategies

Testicular torsion is a challenging and time-sensitive diagnosis that is encountered frequently in daily practice, especially in the emergency room. A thorough history, the presence of a painful and swollen testis and testicular ultrasonography plays a vital role in the prompt diagnosis of testicular torsion. Prompt diagnosis is essential to prevent complications of testicular torsion which include testicular infarction, necrosis, and sub/infertility. This can be challenging as there are various other conditions that may mimic the presentation of testicular torsion. Since testicular torsion is an extremely time-sensitive diagnosis, it may also be a subject of many medicolegal challenges. This review article serves as a guide for clinicians involved with the diagnosis and management of testicular torsion. We review and discuss detection and management strategies based on their validity, statistical significance, and effectiveness in enabling prompt diagnosis and management of testicular torsion. Medicolegal implications of testicular torsion are also highlighted.

Assessment of thyroid gland vascularity with superb microvascular imaging in healthy children and its relationship with potential factors

Objectives To define thyroid gland vascularity index (VI) values in healthy children with the superb microvascular imaging (SMI) method and to assess whether or not there is a correlation with potential factors that may affect these values. Methods This prospective study included a total of 138 children, their ages varying from 3-17 years. Cases were divided into three subgroups according to age: 3-6, 7-12 and 13-17 years. Gender, age, height, weight, body mass index (BMI), thyroid-stimulating hormone (TSH) and free thyroxine (fT4) values were recorded. Volume and SMI measurements were performed with a 14 L5 mHz linear transducer. VI measurements were performed in the transverse and longitudinal planes and correlation with basic descriptive data was researched. Results Mean age was 11.14 ± 3.34 years and BMI was 19.95 ± 4.92. VI values were 4.59 ± 2.34 in the right lobe and 4.23 ± 2.73 for the left lobe, with no significant difference identified. There were no significant differences in mean VI for all parenchyma regarding gender and age groups. While there was no correlation identified with mean VI for all parenchyma with TSH and fT4, there was, however, a negative correlation with BMI. Conclusions Reference VI values for normal thyroid glands in healthy children and adolescents were defined with the SMI method. There was no correlation between the VI values and age, gender, volume, TSH and fT4 values, while there was a negative significant correlation with BMI.

Comparison of Superb Microvascular Imaging With Other Doppler Methods in Assessment of Testicular Vascularity in Cryptorchidism

Superb microvascular imaging (SMI) is a new Doppler technique. Superb microvascular imaging can observe microvascular and low-velocity blood flow. Superb microvascular imaging is available in 2 modes: color SMI (cSMI) and monochrome SMI (mSMI). To evaluate testicular flow, we have compared color Doppler ultrasound (CDUS), power Doppler ultrasound (PDUS), Advanced Dynamic Flow (ADF), cSMI, and mSMI techniques.Fifty-six participants less than 36 months of age were included in the study (mean age, 18.21 ± 1.5 months). One of the testes examined was in the scrotal sac, and the other was undescended testis (UT), and its location was at the level of the lower/middle inguinal canal. Testicular vascularization was evaluated with the CDUS, PDUS, ADF, and SMI techniques. Spot and linear signal encoding detected in the parenchyma were recorded between 0 and III for each technique. At the level of the testicle hilus, the outer boundary of the testicle was drawn manually along the long axis of each testis, and the vascularity index (VI) was automatically calculated from this area on the cSMI method.There was no significant relationship between normal and undescended testicles in terms of age, weight, height, testicle volume, and VI. Superb microvascular imaging was found to be superior in showing testicular vascularity, especially UT. The power of detecting Doppler signal in mSMI is significantly higher than in other methods (P < 0.001). The most valuable method according to the power of detecting testicular vascularity was mSMI. Next were cSMI, ADF, PDUS, and CDUS.In conclusion, the SMI technique should be included in vascular examination in pediatric patients with UT. The SMI technique can play an important role in assessing vascularization of UT.

Ultrasound 2020 - Diagnostics & Therapy: On the Way to Multimodal Ultrasound: Contrast-Enhanced Ultrasound (CEUS), Microvascular Doppler Techniques, Fusion Imaging, Sonoelastography, Interventional Sonography

BACKGROUND

 Ultrasound as a non-ionizing imaging procedure is one of the most important diagnostic procedures in everyday clinical practice. The technology is widely used. Due to constant technical innovations, sonographic procedures, such as contrast-enhanced ultrasound (CEUS), sonoelastography, new microvascular Doppler modalities and, as an example of interventional procedures, sonographically controlled microwave ablation (MWA), are becoming increasingly important in diagnostic imaging and interventional medicine alongside CT and MRI. However, this also requires greater expertise, specialization and qualification on the part of users.

METHOD

 This review article provides information about the range of technical innovations in ultrasound in recent years and describes the underlying technology, the clinical applications, and their diagnostic value. These are presented in the context of the current literature, explaining their advantages and disadvantages and their clinical value.

RESULTS AND CONCLUSION

 Contrast-enhanced ultrasound (CEUS), microvascular Doppler modalities, fusion imaging and elastography complement B-scan ultrasound and conventional Doppler procedures for various problems. Microwave ablation (MWA) has a firm place as an ablative procedure for local tumor therapy in different organ systems and can be performed under ultrasound guidance. Thanks to new developments, the possibilities of ultrasound are now greater than ever. Knowledge of the technology, indications, and possible applications of newer procedures is essential for adequate patient care.

KEY POINTS

  · Contrast-enhanced ultrasound (CEUS) allows an increase in sensitivity and specificity in the assessment of parenchymal lesions.. · CEUS allows the microperfusion to be visualized and quantified. For larger vessels, CEUS is an important instrument in diagnosing endoleak after stenting.. · Microvascular Doppler techniques with clutter suppression algorithms allow a more accurate representation of the smallest vessels than regular color or power Doppler.. · Elastography of the liver in diffuse hepatopathies is a noninvasive diagnostic tool to exclude higher grade fibrosis/cirrhosis.. · Microwave ablation (MWA) also offers sonographically controlled ablation of tumors..

CITATION FORMAT

· Kloth C, Kratzer W, Schmidberger J et al. Ultrasound 2020 - Diagnostics & Therapy: On the Way to Multimodal Ultrasound: Contrast-Enhanced Ultrasound (CEUS), Microvascular Doppler Techniques, Fusion Imaging, Sonoelastography, Interventional Sonography . Fortschr Röntgenstr 2021; 193: 23 - 32.

Acute scrotal pain in pediatric patients: diagnosis with an innovative Doppler technique (MicroV)

Acute scrotal pain is one of the most frequent symptoms in pediatric patients visited in the Emergency Department. Ultrasonography with color and power Doppler represents the first-line method that clinicians use to carry out the differential diagnosis between spermatic cord torsion and inflammation, but sensitivity and specificity are 63-100% and 97-100%, respectively; this variability may be related to operator's experience and testis vascular hemodynamics and also to machine performance and patient age. Recent technological innovations have made possible to create a new Doppler mode called ultrasound microvascular imaging. This technique exploits algorithms capable of separating low frequencies of static tissue artifacts from ones of very weak flows. It is known as MicroV (from Esaote) and Superb microvascular imaging (from Toshiba). It provides both macrocirculation vascular maps, as a typical Doppler feature, and microcirculation vascular maps. Furthermore, the use of background subtraction could improve the visibility of small vascular structures. We report a case of a pediatric patient suffering from acute scrotal pain assessed ultrasonographically with this innovative Doppler technique (MicroV) that may give more confidence in detecting testicular vascular signals if compared with traditional Doppler techniques.

Scrotal Ultrasound Is Not Routinely Indicated in the Management of Cryptorchidism, Retractile Testes, and Hydrocele in Children

Cryptorchidism, or undescended testes, is the most common congenital genitourinary anomaly. A failure or delay of treatment may result in reduced fertility or an increased risk of testicular cancer. The American Urological Association (AUA) recommends that a scrotal ultrasound (SUS) not be performed in the preoperative management of cryptorchidism. This study investigated how likely pediatricians were to perform SUS despite the AUA guidelines. We retrospectively studied 243 patients referred to a single pediatric urology practice for clinically diagnosed testis pathology including undescended testis, hydrocele, and retractile testis over a 4-year period (January 1, 2015, to December 30, 2018). A total of 72 patients (29.6%) underwent a SUS ordered by their pediatrician prior to the pediatric urology visit. Pediatricians should be aware that SUS performed prior to pediatric urological evaluation does not alter management and is associated with a significant financial cost in patients with cryptorchidism or hydrocele.

A comparative study on superb microvascular imaging and conventional ultrasonography in differentiating BI-RADS 4 breast lesions

This prospective study aimed to explore the diagnostic value of superb microvascular imaging (SMI) in differentiating Breast Imaging Reporting and Data System (BI-RADS) 4 breast lesions compared with conventional ultrasonography (US). A total of 111 patients with 116 breast lesions underwent grayscale ultrasound (US), colour Doppler flow imaging (CDFI) and SMI breast imaging between February 2016 and May 2018. CDFI and SMI were performed to evaluate vascular quantity, morphology, and distribution characteristics. The detection of malignancy was compared between grayscale US alone, US + CDFI and US + SMI in terms of the BI-RADS stratification system. SMI was observed to be significantly more accurate in distinguishing malignant breast lesions (86.67%) compared with CDFI (80.00%) (P<0.001). Among malignant lesions, SMI detected 80.00% of those that contained ≥4 vessels, while CDFI only detected 56.67%. Penetrating and branching vessels were identified by SMI in 53.33% of malignant breast lesions and by CDFI in 10.00%. There was no significant difference in vascular distribution by SMI (P=0.094) and by CDFI (P=0.087). US + SMI was associated with higher sensitivity, specificity, and accuracy rates (86.67, 83.72 and 84.48%, respectively) compared with US + CDFI (80.00, 72.09 and 74.14%, respectively). The area under the curve values from receiver operating characteristic analysis of US + SMI, US + CDFI and US alone were 0.852 [95% confidence interval (CI): 0.768–0.936)] 0.760 (95% CI: 0.660–0.860), 0.698 (95% CI: 0.589–0.807), respectively (P<0.001). SMI yielded more detailed vascular information associated with malignant breast masses when compared with conventional US. Therefore, as an adjunct to grayscale, SMI exhibited a markedly improved diagnostic capability in distinguishing malignant and benign breast lesions, particularly those of BI-RADS category 4.

Seeing the Unseen: Evaluating Testicular Vascularity in Neonates by Using the Superb Microvascular Imaging Ultrasound Technique

OBJECTIVES

To evaluate testicular vascularity in neonates by using the novel Superb Microvascular Imaging (SMI; Toshiba Medical Systems Corporation, Tokyo, Japan) ultrasound (US) technique and to compare this technique to conventional Doppler US techniques.

METHODS

A total of 140 healthy neonates between 2 and 60 days old who were admitted for routine screening were included in the study. However, in 9 cases, the Doppler study could not be completed. In the remaining 131 cases, color Doppler imaging (CDI), power Doppler imaging (PDI), Advanced Dynamic Flow (ADF; Toshiba Medical Systems), and monochrome SMI (mSMI) techniques were performed on a single representative testicle. Real-time cine images were captured for 5 to 10 seconds for each technique by using a high-frequency (7.2-14-MHz) linear transducer. The images were evaluated by 3 observers using a grading system to quantify the degree of vascularity and artifact interference.

RESULTS

A total of 131 testicles (74 right and 57 left) were evaluated, and vascularity was shown in 110 (84%) testicles with CDI, 109 (83%) with PDI, 94 (72%) with ADF, and 128 (98%) with mSMI by the consensus of all observers. The Doppler techniques were ranked from highest to lowest in the following order based on the degree of vascularity detected: mSMI > PDI > CDI > ADF (P < .001). Based on the presence of artifacts, the Doppler techniques were ranked as follows from high to low: ADF > CDI > PDI > mSMI (P < .001).

CONCLUSIONS

Superb Microvascular Imaging is a promising US technique that appears to detect testis vascularity better than conventional Doppler US techniques; however, further research is needed to support the results of this study.

Guidelines for ultrasound examination in ophthalmology. Part III: Color Doppler ultrasonography

The aim of this article was to present the possibilities of use and application of color-coded Doppler ultrasonography in the diagnosis of various diseases of the eyeball and orbit which result from vascular disorders. Color-coded Doppler ultrasonography is recommended for the assessment of blood flow velocity in the retrobulbar arteries. That is why the article contains current recommendations for Doppler imaging in ophthalmology. The paper provides detailed recommendations for patient's preparation for the examination, presents the scanning technique and safety of the examination, and lists ophthalmological diseases of vascular origin for which color-coded Doppler ultrasonography can be applied. Furthermore, the article also presents other techniques applied in clinical practice for the assessment of blood flow or imaging of vasculature of a given eyeball structure, inter alia: power Doppler ultrasonography, 3D and 4D ultrasonography, magnetic resonance angiography, spiral computer tomography, transcranial ultrasonography and modern microvascular imaging. The authors emphasize the usefulness of color-coded Doppler ultrasonography in the diagnosis of diseases which result from blood flow disorders within the eyeball, such as amaurosis fugax, ocular ischemic syndrome, insufficiency in vessels supplying the carotid and vertebral arteries, posterior ischemic optic neuropathy, glaucoma, age-related macular degeneration, vascular vision disorders, vascular malformations, such as arteriovenous fistula, orbital varices, systemic connective tissue diseases in retinopathy of prematurity, diabetes, thyroid disorders or strabismus. The application of color-coded Doppler ultrasonography is especially important in the assessment of the vasculature of intrabulbar tumorous lesions and in the differential diagnosis of intrabulbar tumors.

The aim of this article was to present the possibilities of use and application of color-coded Doppler ultrasonography in the diagnosis of various diseases of the eyeball and orbit which result from vascular disorders. Color-coded Doppler ultrasonography is recommended for the assessment of blood flow velocity in the retrobulbar arteries. That is why the article contains current recommendations for Doppler imaging in ophthalmology. The paper provides detailed recommendations for patient’s preparation for the examination, presents the scanning technique and safety of the examination, and lists ophthalmological diseases of vascular origin for which color-coded Doppler ultrasonography can be applied. Furthermore, the article also presents other techniques applied in clinical practice for the assessment of blood flow or imaging of vasculature of a given eyeball structure, inter alia: power Doppler ultrasonography, 3D and 4D ultrasonography, magnetic resonance angiography, spiral computer tomography, transcranial ultrasonography and modern microvascular imaging. The authors emphasize the usefulness of color-coded Doppler ultrasonography in the diagnosis of diseases which result from blood flow disorders within the eyeball, such as amaurosis fugax, ocular ischemic syndrome, insufficiency in vessels supplying the carotid and vertebral arteries, posterior ischemic optic neuropathy, glaucoma, age-related macular degeneration, vascular vision disorders, vascular malformations, such as arteriovenous fistula, orbital varices, systemic connective tissue diseases in retinopathy of prematurity, diabetes, thyroid disorders or strabismus. The application of color-coded Doppler ultrasonography is especially important in the assessment of the vasculature of intrabulbar tumorous lesions and in the differential diagnosis of intrabulbar tumors.

A Prospective Study to Compare Superb Microvascular Imaging with Grayscale Ultrasound and Color Doppler Flow Imaging of Vascular Distribution and Morphology in Thyroid Nodules

Background

This study aimed to compare superb microvascular imaging (SMI) with grayscale ultrasound (US) and color Doppler flow imaging (CDFI) to evaluate vascular distribution and morphology to distinguish between benign and malignant thyroid nodules.

Material/Methods

Seventy-one patients with 76 thyroid nodules underwent grayscale US, CDFI, and SMI thyroid imaging. CDFI and SMI assessed vascular quantity, morphology, and distribution, and was graded according to Adler’s method, as absent (grade 0), minimal (grade 1), moderate (grade 2), or marked (grade 3). The detection of malignancy was compared between the following imaging groups, grayscale US alone, US combined with CDFI, and US combined with SMI.

Results

SMI was significantly more accurate in identifying malignant thyroid nodules (79.3%) compared with CDFI (55.2%) (P<0.001). In malignant thyroid nodules, penetrating blood vessels were identified by SMI in 62.1% and by CDFI in 41.4%; there was no significant difference in vascular distribution between SMI (P=0.835) and CDFI (P=0.806). Grayscale US with SMI resulted in the greatest diagnostic sensitivity, accuracy, and specificity (86.21%, 85.53%, and 85.11%) compared with grayscale US with CDFI (75.86%, 82.89%, and 87.23%). Receiver operating characteristic (ROC) area under the curve (AUC) values of US with SMI, US with CDFI, and US alone were 0.918 (95% CI, 0.856–0.979), 0.911 (95% CI, 0.849–0.973), and 0.847 (95% CI, 0.762–0.932), respectively (P<0.001).

Conclusions

SMI as an adjunct to grayscale US provided significantly more information on vascularity associated with malignancy in thyroid nodules, when compared with grayscale US or with US and CDFI.