Application of constrast-enhanced ultrasound-micro flow imaging technique in differential diagnosis of benign and malignant renal tumors / 中华超声影像学杂志

ABSTRACT

Objective:To explore the value of constrast-enhanced ultrasound-micro flow imaging (CEUS-MFI) in the differential diagnosis of benign and malignant renal tumors.Methods:Totally 96 patients with renal space occupying found in two-dimensional gray-scale ultrasound examination in the First Affiliated Hospital, College of Medicine, Zhejiang University from November 2020 to August 2021 were collected, and 97 lesions were examined by CEUS-MFI and constrast-enhanced ultrasound(CEUS), respectively. The microvascular morphology and contrast-enhanced characteristics of renal tumors were recorded, ROC curves were constructed, and the diagnostic efficacies of the two methods were compared.Results:In the CEUS examination, the enhancement modes of malignant tumors were mainly fast wash-in(52/66, 78.8%) and fast wash-out (49/66, 74.2%) and high perfusion (56/66, 84.8%), and ring enhancement can be seen in 48.5%(32/66) of the lesions. The enhancement patterns of benign tumors were mainly slow wash-in (17/31, 54.8%) and slow wash-out (20/31, 64.5%) and low perfusion (18/31, 58.1%), and no circular blood flow was found in 31 lesions.In the CEUS-MFI examination, the vascular morphology of malignant tumors was mainly irregular (46/66, 69.7%), 93.9%(62/66) of malignant tumors had circular blood flow. Most of benign tumors were of linear vascular structure(12/31, 38.7%) and dendritic vascular structures (14/31, 45.2%), 93.5% (29/31) of benign tumors showed no circular blood flow. The detection rate of the annular blood flow in malignant tumors by CEUS-MFI was higher than that by CEUS, and the difference was statistically significant (93.9% vs 48.5%, P<0.001). The accuracy, sensitivity, and specificity of diagnosing renal tumors for using CEUS-MFI were 90.7%, 93.9% and 83.8%, respectively; and 84.5%, 92.4% and 67.7%, respectively, for using CEUS. The areas under the ROC curve were 0.898 and 0.814 for using CEUS-MFI and CEUS, respectively, the difference between the two techniques was not significant ( P=0.151). Conclusions:CEUS-MFI can sensitively and clearly display the microvascular morphology inside the tumor, and greatly improve the detection rate of annular blood flow in renal malignant tumors, which provides a new method for clinicians to identify benign and malignant renal tumors.