Quantitative Analysis of Perfusion Characteristics Using Contrast-Enhanced Ultrasound in Patients with Choroidal Metastasis

Purpose: The aim of the study was to quantitatively analyze the perfusion characteristics of choroidal metastasis using contrast-enhanced ultrasound (CEUS) and compare its perfusion characteristics with these of choroidal hemangioma and choroidal melanoma. Methods: The patients who were clinically diagnosed with choroidal metastasis were classified as the study group, and the patients who were diagnosed with choroidal hemangioma and choroidal melanoma during the same period were classified as the comparison group. All patients underwent CEUS examination, and Sonoliver was used to obtain the data on quantitative parameters of the tumor and the adjacent normal orbital tissues, including maximum of intensity (IMAX), rise time (RT), time to peak (TTP), and mean transit time (mTT). Wilcoxon signed rank test was performed to compare the quantitative parameters of choroidal metastasis and normal orbital tissues. Kruskal-Wallis test was adopted to compare the quantitative parameters of the 3 types of tumors, and Bonferroni was used to correct the results of the multiple comparisons. Receiver operating characteristic (ROC) curve analysis was used to identify valuable parameters. Results: Twenty-six patients (26 eyes) with choroidal metastasis, 55 patients (55 eyes) with choroidal hemangioma, and 49 patients (49 eyes) with choroidal melanoma were enrolled in this study. The IMAX of choroidal metastasis was significantly higher than that of normal orbital tissues, while RT, TTP, and mTT were significantly shorter than these of normal orbital tissues (all p values were <0.001). The IMAX of choroidal metastasis was lower than that of choroidal hemangioma, and RT, TTP, and mTT were shorter than these of choroidal hemangioma and choroidal melanoma (p = 0.002, p = 0.004, p = 0.007). ROC curve analysis showed that areas under the ROC curves (AUCs) of RT and mTT (AUC = 0.851, 95% CI 0.783-0.918 and 0.849, 95% CI 0.783-0.915) were larger. Conclusion: Quantitative analysis with CEUS can reflect the perfusion characteristics of choroidal metastasis and can exhibit the difference between its perfusion characteristics and these of choroidal hemangioma and choroidal melanoma. RT and mTT may serve as useful parameters for differentiating choroidal metastasis from choroidal hemangioma and choroidal melanoma.