Role of Contrast-Enhanced Ultrasound in Pulmonary Lesions: 5-Year Experience at a Single Center

Comparative Study of Sonazoid and SonoVue Contrast-Enhanced Ultrasound Quantitative Analysis Parameters in Peripheral Lung Cancer Lesions

PURPOSE

Lung cancer is a leading cause of death; however, its diagnosis needs to be improved. This study aimed to compare the performances of the contrast agents Sonazoid and SonoVue in quantitative analysis in the contrast-enhanced ultrasound (CEUS) of peripheral lung cancer lesions (PLCLs).

METHODS

This retrospective study included patients with PLCLs between January 2021 and January 2024. They were divided into the Sonazoid-CEUS (50 patients) and SonoVue-CEUS (53 patients) groups. In the CEUS video, lesions and adjacent normal lung tissues were selected as regions of interest to obtain time-intensity curves. Seven CEUS indicators were used to compare the performances of the two contrast agents.

RESULTS

The arrival times (ATs) were 13.1 ± 5.2 s and 11.5 ± 3.7 s for PLCLs (p = 0.087), respectively, and 8.0 ± 4.1 s and 7.0 ± 4.2 s for adjacent lung tissues (p = 0.197), respectively, in the Sonazoid and SonoVue groups. The peak intensity (PI) and area under the curve (AUC) of the lesions in the Sonazoid group were significantly lower than those in the SonoVue group (PI: 25.0 ± 11.5 vs. 35.8 ± 7.9, p < 0.001; AUC: 2365.2 ± 1708.2 vs. 4309.5 ± 1252.1, p < 0.001). The time to peak (TTP), mean transition time (MTT), and lesion-lung PI difference (ΔPI) in the Sonazoid group were significantly higher than those in the SonoVue group (TTP: 36.3 ± 13.8 s vs. 24.4 ± 8.7 s, p < 0.001; MTT: 119.6 ± 45.3 s vs. 80.6 ± 21.4 s, p < 0.001; ΔPI: 14.3 ± 10.9 vs. 8.4 ± 6.1, p < 0.01).

CONCLUSION

Sonazoid and SonoVue exhibited comparable quantitative performances in CEUS of PLCLs; the higher ΔPI of Sonazoid suggests it may enhance the contrast between lesions and adjacent tissues. The study's findings could help improve lung cancer diagnosis.

Accuracy of Contrast-enhanced Ultrasonography with Perfluorobutane for Diagnosing Subpleural Lung Lesions

RATIONALE AND OBJECTIVES

To investigate the diagnostic value of perfluorobutane-enhanced ultrasound (US) examinations for differentiating benign from malignant subpleural lung lesions.

METHODS

This single-center, retrospective study enrolled consecutive patients with subpleural lung lesions between January 2022 and March 2023. The cause of the lung lesions was confirmed by biopsy and follow-up examinations. The lesions were continuously evaluated using perfluorobutane-enhanced US for 0-180 s, and washout (WT) was observed after 3, 5, and 10 min. Univariate and multivariate analyses were used to identify significant US features, which were evaluated for their diagnostic performance. The diagnostic performance of combining several features for predicting malignant lung lesions was also assessed by multivariate logistic regression analysis.

RESULTS

Seventy cases were included (17 benign lesions [13 men, 4 women; mean age: 57.5 ± 12.2 years] and 53 malignant lesions [41 men, 12 women; mean age: 63.3 ± 11.6 years]). Peak intensity (PI), arrival time (AT), and WT after 10 min significantly differed between malignant and benign lesions. The sensitivity and accuracy were significantly higher for 10-minute WT than for AT (both p < 0.05). The area under the curve of the combined diagnostic evaluation with AT, PI, and 10-minute WT was 0.897 (95% [CI]: 0.806-0.988), which was significantly higher than that of AT or PI alone.

CONCLUSION

Perfluorobutane-enhanced US can differentiate benign from malignant lung lesions, and combining AT, PI, and 10-minute WT for diagnostic purposes performed better than a single feature.

Diagnosis of pulmonary adenoid cystic carcinoma using multimodal ultrasound imaging technology: A case report

RATIONALE

Pulmonary adenoid cystic carcinoma (PACC) is an exceedingly uncommon malignant tumor originating from salivary glands.

PATIENT CONCERNS

We present a case of primary PACC with multiple lung metastases in a 48-year-old male patient.

DIAGNOSIS

Diagnosis involved grayscale ultrasound, shear wave elastography, contrast-enhanced ultrasound, and ultrasound-guided percutaneous lung biopsy, all conducted in a one-stop manner, and confirmed by pathological examination.

INTERVENTIONS

Treatment was recommended after the diagnosis was confirmed, but was not accepted.

OUTCOMES

With telephone follow-up, the patient survived.

LESSONS

PACC is an exceedingly uncommon malignant tumor originating from salivary glands. Compared to other cases, this case highlights the potential of multimodal ultrasound imaging for diagnosing lung tumors.

Clinical utility of bedside Contrast-Enhanced Ultrasound (CEUS) in the diagnosis of pneumonia in elderly patients: Comparison with clinical, -radiological and ultrasound diagnosis

AIMS

to measure the clinical impact of contrast-enhanced ultrasound (CEUS) in the diagnosis of -community-acquired pneumonia (CAP), compared to clinical, radiological and ultrasound diagnosis.

METHODS

84 patients (47/37 males/females, mean age:78,57±11,7 Y) with clinical suspicion of pneumonia and with ultrasound findings of peripheral lung lesions, were investigated with CEUS for a better characterization. Final diagnosis of 65 cap was obtained with complete disappearance of symptoms and pulmonary nodule(s); 19 neoplasms: 16 patients performed histologically with bronchoscopy; 3 refused (non-invasive diagnosis with basal CT-scan and positron emission tomography (PET) with fluorodeoxyglucose (FDG)). Sensitivity, specificity, overall diagnostic accuracy (ODA) (and corresponding AUROC) of clinical-data (CD), chest X-ray(CXR), Lung-ultrasound(LUS), CEUS were calculated with SPSS 26.0 software.

RESULTS

Final diagnosis: 65 CAP, and 19 chest cancers. 9/65 (13%) patients died, of these 7/9 with older age and heart disease as comorbidity. CD: True-Positive (TP):23, True-negative (TN): 17; False-Positive (FP):2; False-negative (FN):42 (sens:35,4% spec:89,5% ODA10%: PPV:92%, NPV:28,8%) (AUROC±SEauc:0,46±0,076); CXR: TP: 36, TN:14; FP:5, FN:29; (sens: 55,4%; spec: 73,7%; ODA: 32%; PPV:87,5%, NPV:32,66%) (AUROC±SEauc:0,645±0,068). US: TP:59; TN: 14; FP:5, FN:6 (sens: 90,8%, spec: 73,7%, ODA: 84,9%, PPV:92,2%, NPV:70%) (AUROC±SEauc:0,9417±0,024); CEUS: TP: 63; TN: 19; FP:0; FN:2 (sens: 96,9%; spec: 100% ODA: 97,5%; PPV: 100%, NPV:90,5%) (AUROC±SEauc:0,98±0,01).

CONCLUSIONS

Clinical-data and chest X-RAYS are insufficient to obtain a correct diagnosis of CAP in elderly population; US demonstrated a good accuracy to establish CAP, but with a relatively low specificity; in these cases, CEUS is able to give a correct characterization, allowing you to save the need for a chest contrast-enhanced-CT (CECT).

Perfusion Patterns of Peripheral Pulmonary Metastasis Using Contrast-Enhanced Ultrasound (CEUS) and Their Correlation with Immunohistochemically Detected Vascularization Pattern

PURPOSE

Description of the perfusion of pulmonary metastasis by contrast-enhanced ultrasound (CEUS) and their correlation with vascularization patterns represented by immunohistochemical CD34 endothelial staining.

PATIENTS AND METHODS

The data of 54 patients with histologic proven peripheral pulmonary metastasis, investigated between 2004 and 2023 by CEUS. These CEUS parameters were evaluated: time to enhancement (TE), categorized as early pulmonary-arterial (PA) or delayed bronchial-arterial (BA) patterns; extent of enhancement (EE), either marked or reduced; homogeneity of enhancement (HE), homogeneous or inhomogeneous; and decrease of enhancement (DE), rapid washout (<120 s) or late washout (≥120 s). Additionally, tissue samples in 45 cases (83.3%) were stained with CD34 antibody for immunohistochemical analysis.

RESULTS

In total, 4 lesions (7.4 %) exhibited PA enhancement, and 50 lesions (92.6%) demonstrated BA enhancement. Furthermore, 37 lesions (68.5%) showed marked enhancement, while 17 lesions (31.5%) exhibited reduced enhancement. The enhancement was homogeneous in 28 lesions (51.86%) and inhomogeneous in 26 lesions (48.14%). Additionally, 53 lesions (98.1%) displayed a rapid washout. A chaotic vascular pattern indicative of a bronchial arterial blood supply was identified in all cases (45/45, 100%), including all 4 lesions with PA enhancement.

CONCLUSION

Pulmonary metastases in CEUS predominantly reveal bronchial arterial enhancement and a rapid washout. Regarding EE and HE, pulmonary metastases show heterogeneous perfusion patterns. A PA enhancement in CEUS does not exclude BA neoangiogenesis.

Conventional and Contrast-enhanced US of the Lung: From Performance to Diagnosis

In recent years, lung US has evolved from a marginal tool to an integral component of diagnostic chest imaging. Contrast-enhanced US (CEUS) can improve routine gray-scale imaging of the lung and chest, particularly in diagnosis of peripheral lung diseases (PLDs). Although an underused tool in many centers, and despite inherent limitations in evaluation of central lung disease caused by high acoustic impedance between air and soft tissues, lung CEUS has emerged as a valuable tool in diagnosis of PLDs. Owing to the dual arterial supply to the lungs via pulmonary and bronchial (systemic) arteries, different enhancement patterns can be observed at lung CEUS, thereby enabling accurate differential diagnoses in various PLDs. Lung CEUS also assists in identifying patients who may benefit from complementary diagnostic tests, including image-guided percutaneous biopsy. Moreover, lung CEUS-guided percutaneous biopsy has shown feasibility in accessible subpleural lesions, enabling higher histopathologic performance without significantly increasing either imaging time or expenses compared with conventional US. The authors discuss the technique of and basic normal and pathologic findings at conventional lung US, followed by a more detailed discussion of lung CEUS applications, emphasizing specific aspects of pulmonary physiology, basic concepts in lung US enhancement, and the most commonly encountered enhancement patterns of different PLDs. Finally, they discuss the benefits of lung CEUS in planning and guidance of US-guided lung biopsy. ©RSNA, 2024 Supplemental material is available for this article.

Diagnosis of benign and malignant peripheral lung lesions based on a feature model constructed by the random forest algorithm for grayscale and contrast-enhanced ultrasound

Rationale and objectives

To construct a predictive model for benign and malignant peripheral pulmonary lesions (PPLs) using a random forest algorithm based on grayscale ultrasound and ultrasound contrast, and to evaluate its diagnostic value.

Materials and methods

We selected 254 patients with PPLs detected using chest lung computed tomography between October 2021 and July 2023, including 161 malignant and 93 benign lesions. Relevant variables for judging benign and malignant PPLs were screened using logistic regression analysis. A model was constructed using the random forest algorithm, and the test set was verified. Correlations between these relevant variables and the diagnosis of benign and malignant PPLs were evaluated.

Results

Age, lesion shape, size, angle between the lesion border and chest wall, boundary clarity, edge regularity, air bronchogram, vascular signs, enhancement patterns, enhancement intensity, homogeneity of enhancement, number of non-enhancing regions, non-enhancing region type, arrival time (AT) of the lesion, lesion-lung AT difference, AT difference ratio, and time to peak were the relevant variables for judging benign and malignant PPLs. Consequently, a model and receiver operating characteristic curve were constructed with an AUC of 0.92 and an accuracy of 88.2%. The test set results showed that the model had good predictive ability. The index with the highest correlation for judging benign and malignant PPLs was the AT difference ratio. Other important factors were lesion size, patient age, and lesion morphology.

Conclusion

The random forest algorithm model constructed based on clinical data and ultrasound imaging features has clinical application value for predicting benign and malignant PPLs.

Contrast-enhanced ultrasound (CEUS) - A new tool for evaluating blood supply in primary peripheral lung cancer

OBJECTIVES

To explore the feasibility of contrast-enhanced ultrasound (CEUS) as a new tool for characterizing vascularization of primary peripheral lung cancer.

METHODS

315 consecutive patients with definite primary peripheral lung cancers underwent CEUS examination from November 2016 to March 2022. CEUS parameters including time to enhancement (TE), time to peak (TP), time to wash-out (TW), distribution of vessels (DV), extent of enhancement (EE) and homogeneity of enhancement (HE) were obtained.

RESULTS

The lesions were grouped on the basis of TE which reflects tumor vascularization: early enhancement (pulmonary arterial vascularization) (n = 91) and delayed enhancement group (bronchial arterial vascularization) (n = 224). Overall, lung tumors commonly (71.1%) manifested a delayed enhancement which indicating blood supply originated from bronchial arteries, while an early enhancement was present in less than a third of the cases. Tumors with bronchial vascularization tended to show a delayed, reduced and heterogeneous enhancement. Correspondingly, it is characterized by a shorter TE, marked EE and a relatively infrequent occurrence of necrosis in tumors with pulmonary vascularization.

CONCLUSIONS

Providing micro-perfusion information, CEUS is a potentially imaging tool for evaluating blood supply in primary peripheral lung cancer.