Evaluation of esophageal varices using contrast‐enhanced coded harmonic ultrasonography

Aim:  To investigate if esophageal varices can be evaluated using external contrast-enhanced ultrasonography with Levovist and coded harmonic angio (CHA). Methods:  Subjects were six healthy adult volunteers and 23 patients with liver cirrhosis. After identification of the lower esophagus under B-mode scanning, 300 mg/mL of Levovist was intravenously injected into the cubital vein at a rate of 1 mL/s under observation by CHA-mode scanning. Approximately 30 s after intravenous administration, interval-delay scanning was performed every second to visualize the area around the lower esophageal lumen. The degree of ultrasonographic enhancement was assessed as either no enhancement (negative); linear enhancement along the esophageal wall (weak) or full enhancement of the esophageal lumen (strong). Endoscopic evaluation of esophageal varices was also performed. Results:  The CHA enhancement around the lower esophageal lumen was identified in 21 of the 23 patients. Of these 21 patients, endoscopic assessments of varices were as follows: F0 in four patients, F1 in seven patients, F2 in three patients, and F3 in seven patients. Nine patients were red color sign (RCS)-positive. Regarding the relationship between ultrasonographic enhancement and endoscopic assessment, enhancement was identified as negative in all four F0 patients, negative in three and weak in three and strong in one of the seven F1 patients, weak in one and strong in two of the three F2 patients, and weak in two and strong in five of the seven F3 patients, respectively. Furthermore, of the nine RCS-positive patients, enhancement was recognized as strong in seven and weak in two patients. Ultrasonographic enhancement was identified as negative in all six healthy volunteers. Conclusions:  By performing contrast-enhanced CHA ultrasonography using Levovist, ultrasonographic enhancement was detectable in all patients with varices categorized as F2 or above. Because the present method is easy to perform and causes less pain to patients compared to endoscopy, it is useful for following and assessing esophageal varices in patients with liver cirrhosis.