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

Treatment response assessment to chemotherapy with bevacizumab for colorectal liver metastasis by contrast-enhanced ultrasound

Background

Though contrast-enhanced ultrasound (CEUS) perfusion parameters have been approved to be potential indicators for response to chemotherapy in solid tumors, their ability in assessment of colorectal liver metastasis (CRLM) to chemotherapy with bevacizumab (Bev) has rarely been investigated.

Methods

From March 2021 to May 2022, 115 consecutive CRLM patients with CEUS pre- and post-2 months' chemotherapy with Bev were prospectively enrolled. One target lesion per patient underwent CEUS quantitative analysis with SonoLiver software. Rise time, time-to-peak, mean transit time, maximal intensity (IMAX), and area under the time-intensity curve (AUC) were assessed with region of interest (ROI) selected on whole lesion, lesion periphery, and internal lesion, respectively. The reduction and ratio of post- to pre-treatment in parameters were investigated in development cohort (n=89) and validated in internal validation cohort (n=26) according to the chronological order.

Results

With modified Response Evaluation Criteria in Solid Tumor as reference, 48, 14 responders and 41, 12 non-responders were included in development and validation cohort, respectively. Significantly smaller values of IMAX and AUC on ROIwhole, ROIperipheral, and ROIinternal, were observed post-treatment in development cohort (all P<0.05). In predicting treatment response, the influence of ROI selection was observed when using ∆IMAX and ∆AUC, while no influence was observed using ratios. Areas under the receiver operating characteristic curve (AUROCs) for ∆IMAX and ∆AUC on ROIperipheral were 0.939 (0.867-0.979), 0.951 (0.883-0.985), and 0.917 (0.740-0.988), 0.923 (0.748-0.990) in development and validation cohort, respectively. For ratios of IMAX and AUC, AUROCs were 0.976 (0.919-0.997), 0.938 (0.865-0.978), and 0.899 (0.717-0.982), 0.982 (0.836-1.000) in development and validation cohort, respectively.

Conclusions

IMAX and AUC showed significant reductions in responders, and different analyses ROIs influence the performance of ∆IMAX and ∆AUC in response assessment. Parameters derived from ROI peripheral exhibited the most promising results in predicting treatment response.

Superb microvascular imaging for evaluation of microvascularity in breast nodules compared with conventional Doppler imaging

Background

Neovascularity visualization in breast nodules is challenging due to the limitations of conventional Doppler imaging methods. This study aims to assess the performance of superb microvascular imaging (SMI) in evaluating the microvascularity of breast nodules (diameter ≤2 cm). The comparison of performances of SMI with color Doppler flow imaging (CDFI) and power Doppler imaging (PDI) was made by using a three-factor scoring system of vascularity. This study also investigated the common features of microvascularity in small malignant nodules on SMI for early differentiating from benign nodules.

Methods

Ninety-one female patients (with 125 breast nodules) were enrolled in this retrospective study. All the breast nodules were examined by grayscale ultrasonography (US), CDFI, PDI, and SMI. The number, morphologic features, and distribution of blood vessels were scored to evaluate the nodular vascularity in light of the three-factor scoring system. The diagnostic value of SMI for microvascularity in breast nodules was analyzed and compared with CDFI and PDI.

Results

Histological analysis showed 53 malignant and 72 benign nodules. The vascularity grades detected by SMI were significantly different from those of CDFI and PDI (P<0.05). SMI detected 47 grade-IV nodules of the total 125 nodules (37.6%), which was more than those detected by CDFI (10.4%, 13/125) and PDI (12.8%, 16/125), while more grade-I nodules were detected by CDFI (42.4%, 53/125) and PDI (36.8%, 46/125) compared with SMI (21.6%, 27/125). Differences in the vessel number, morphologic features, and distribution between benign and malignant breast nodules were significant on SMI (P<0.05). The vessel number ≥6, penetrating vessels, and a mixed distribution of vessels in peripheral and central nodular tissues were the common features of microvascularity in the grade-IV malignant nodules on SMI, whereas the blood vessels in the benign nodules were straight and branching and peripherally distributed.

Conclusions

In comparison with CDFI and PDI, SMI enhances microvascularity detection, depicts the microvascular architecture in breast nodules and has potential in the differential diagnosis of malignant nodules from benign nodules.

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.

[Ultrasound diagnostics: Differentiated vision - upgrading - better reimbursement]

Ultrasonography is an imaging modality of great importance in everyday clinical practice. Technical innovations continuously expand the diagnostic and therapeutic possibilities of ultrasonography requiring continuous upskilling of sonographers. Only a small number of practitioners, in hospital and practice settings in Germany, currently have the required level of skills. Therefore, these techniques are not as readily available as would be desirable. A modern high-end ultrasound scanner in the hands of a qualified sonographer is a diagnostic high-tech precision instrument, which can compete with any other imaging modality.In conclusion, basic sonography, as it is currently practised should be separated from high-end sonography, requiring extensive training and better remuneration. In this context the introduction of a new medical board speciality for ultrasonography, "Advanced Ultrasonography", with corresponding upgrading should be recommended for high-end sonography.

The role of contrast-enhanced ultrasound in the evaluation of hepatobiliary lesions and its correlation with pathological findings

Purpose

To evaluate the efficacy of contrast-enhanced ultrasound (CEUS) in assessing hepatobiliary lesions, and to correlate the findings of CEUS for hepatobiliary lesions with those of pathological examination performed through fine needle aspiration.

Material and methods

This prospective observational study included 50 patients with hepatobiliary lesions, who were referred for CEUS. The findings of CEUS were correlated with pathological findings.

Results

CEUS was determined to be a highly sensitive and specific imaging modality for the detection and characterization of hepatobiliary lesions, with the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CEUS being 100.0%, 96.8%, 66.7%, 100.0%, and 96.7%, respectively, when correlated with pathological findings.

Conclusions

CEUS is a highly sensitive and specific imaging modality for the detection and characterization of hepatobiliary lesions, with wide availability in the present scenario.

Evaluation of the Metabolic Activity of the Infiltration and Proliferation Areas of Hepatic Alveolar Echinococcosis in Rats Using Contrast-Enhanced Ultrasound

This study evaluated the value of contrast-enhanced ultrasound (CEUS) in assessing the metabolic activity of infiltration and proliferation areas of hepatic alveolar echinococcosis (HAE) in rats. CEUS was performed on Wistar rats with HAE. The average grayscale value of the HAE lesion in peripheral infiltration and proliferation areas (PIPAs) and the adjacent normal liver tissue was analyzed quantitatively. Contrast imaging was classified as highly increased enhancement, moderately increased enhancement, and equal or decreased enhancement. Microvessel density (MVD) in the PIPAs was classified as strongly positive, moderately positive, and weakly positive. The metabolic activity of HAE in the PIPAs was classified as high activity, moderate activity, and low activity according to the MVD classification results. The kappa test was combined with the metabolic activity level of the PIPAs to analyze the consistency of CEUS intensity and MVD. CEUS can score the metabolic activity of the infiltration and proliferation areas around HAE lesions, and provides a basis for clinical treatment and follow-up visits. CEUS could be used as a more economical and effective imaging option for evaluating the metabolic activity of HAE lesions.

Contrast-enhanced ultrasound (CEUS) in patients with metastasis-like hepatic alveolar echinococcosis: a cohort study

PURPOSE

Hepatic alveolar echinococcosis (HAE) of the metastasis-like pattern, according to the Echinococcus Ulm classification, is usually discovered as an incidental finding, and the diagnostic differentiation from "true metastases" is difficult. The aim of this study was to investigate whether lesions of the "metastasis-like pattern" in HAE show a typical contrast behavior that can be used for differentiation from metastasis in malignancies.

METHODS

This prospective clinical study included 11 patients with histologically confirmed HAE of the metastasis-like pattern (7 female and 4 male; mean age, 57.1 years; mean disease duration, 59.5 months), who had been examined by B-scan sonography and CEUS, from the National Echinococcosis Registry Germany.

RESULTS

On contrast-enhanced sonography, 11/11 reference lesions showed annular rim enhancement in the arterial and portal venous phases. Throughout the entire 4-min study period, none of the reference lesions showed central contrast enhancement-i.e., all exhibited a complete "black hole sign". A small central scar was seen in 81.8% of cases.

CONCLUSION

In clinically unremarkable patients with incidentally detected metastasis-like lesions of the liver, contrast-enhanced sonographic detection of rim enhancement without central contrast uptake (black hole sign) should be considered evidence supporting a diagnosis of hepatic alveolar echinococcosis with a rare metastasis-like pattern. This can help to differentiate HAE from metastases, especially in high-endemic areas.