The Value of High‐Frequency Ultrasound and Color Doppler Flow Imaging in Assessing the Efficacy of Moderate‐to‐Severe Acne Vulgaris: A Prospective Single‐Arm Study

HFUS effectively visualizes deep acne lesions (nodules/cysts). Although ultrasound grading demonstrates slower severity reduction than clinical assessment, it provides more objective severity evaluation. CDFI enhances hemodynamic analysis through real-time flow visualization. Combined HFUS/CDFI enables enhanced severity and prognostic assessment in moderate-to-severe acne vulgaris.