Super-Resolution Ultrasound for Microvascular-Based Differentiation of Benign and Malignant Choroidal Tumors: A Preliminary Study.

OBJECTIVE

To assess the diagnostic utility of super-resolution ultrasound (SRUS) in differentiating benign from malignant choroidal tumors based on microvascular characteristics.

METHODS

This prospective study enrolled 79 patients with choroidal tumors, including 41 malignant and 38 benign lesions. All participants underwent conventional ultrasound (US), contrast-enhanced ultrasound, and SRUS examinations. SRUS images were qualitatively evaluated for microvascular disorganization and complexity and quantitatively analyzed using multiple vascular parameters. The diagnostic performance of different ultrasound models was assessed using the area under the receiver operating characteristic curve (AUC), sensitivity, and specificity.

RESULTS

Malignant tumors exhibited significantly higher fractal dimension (FD), velocity variance (Vel Var), velocity entropy (Vel Ent), and directional variance (Dir Var), along with lower minimum velocity (Vmin), compared with benign lesions (all p < 0.05). Among these parameters, FD showed the most prominent difference (p = 0.002). In model analysis, the B-mode-only model showed limited diagnostic performance (AUC = 0.645, 95% CI: 0.520-0.758). After incorporating CEUS parameters, the AUC increased to 0.795 (95% CI: 0.695-0.885). The B-mode + SRUS model further improved the diagnostic performance (AUC = 0.865, 95% CI: 0.775-0.938). The combined B-mode + CEUS + SRUS model achieved the highest diagnostic accuracy with an AUC of 0.913 (95% CI: 0.846-0.966).

CONCLUSION

This preliminary study suggests that SRUS enables detailed visualization and quantitative assessment of choroidal tumor microvasculature and may provide additional value as a noninvasive imaging technique for differentiating benign from malignant lesions.