Contrast-enhanced ultrasound using SonoVue mixed with oral gastrointestinal contrast agent to evaluate esophageal hiatal hernia: Report of three cases and a literature review

Figure 1 Optimization of the contrast agent mixture in normal volunteers. A: Gray-scale and contrast-enhanced ultrasound showed mild and insufficient enhancement of the upper gastrointestinal tract at the mixture ratio of 1 mL:500 mL; B: The 2.5 mL:500 mL ratio mixture produced homogenous moderate enhancement with good sound penetrability and margin delineation appearing within the esophagus and stomach. Arrows indicate the esophageal hiatus; C: The 5 mL:500 mL ratio mixture produced strong enhancement reflection with obvious far-field sound attenuation (triangle). ES: Esophagus; ST: Stomach.