Inclusion Criteria:  Age ≥ 18 years old and ≤ 80 years old; Patients with enlarged lymph nodes detected by ultrasound; No contraindications such as hypersensitivity to contrast-enhanced ultrasound; Voluntarily enrolled in this research project  Exclusion Criteria:  The patient's position cannot be matched during ultrasound examination  Treatment history of lesion area: operation, radiotherapy, intervention, etc ③ Patients without informed consent ④ Lack of clinical data (no effective images such as two-dimensional ultrasound, color Doppler, contrast-enhanced ultrasound, micro blood flow imaging, or poor image quality, unable to analyze, unknown pathological results, etc.) ⑤ Lack of follow up information