Utility of Transabdominal Ultrasonography Enhanced by Oral Cellulose-Based Contrast Agent in Depicting Varices at Cardia and Fundus

Abstract

The use of transabdominal color Doppler ultrasound after oral administration of an oral cellulose-based contrast agent (TUS-OCCA) in depicting varices at the cardia and fundus was explored. Both gastroscopy and transabdominal color Doppler ultrasound (TUS) were performed for this purpose, with gastroscopy serving as the gold standard. Patients were assigned by TUS protocol to one of three groups: TUS + empty stomach (TUS-ES); TUS + oral water intake (TUS-OW); and TUS-OCCA. TUS-based grading of varices reflected venous diameters and blood flow velocities, designated as follows: Ux = difficulty discerning gastric fundus and cardia or delineating varices; U0 = no detectable varices; U1 = diameter <5 mm, flow rate <10 cm/s; U2 = diameter <5 mm, flow rate ≥10 cm/s; U3 = diameter 5-10 mm, flow rate <10 cm/s; U4 = diameter 5-10 mm, flow rate ≥10 cm/s; and U5 = diameter >10 mm, any flow rate. Between August 2016 and August 2019, 239 patients with cirrhosis were enrolled prospectively, including bleeding (n = 71) and non-bleeding (n = 168) groups. Varices were directly observed in 10.5% (25/239) of TUS-ES group members, compared with 59.2% (58/98) of the TUS-OW group and 89.6% (104/116) of the TUS-OCCA group; all detection rates differed significantly (TUS-OCCA > TUS-OW > TUS-ES, p < 0.05). TUS-based grading (as defined) revealed the following patient distribution: Ux, n = 34; U0, n = 18; U1, n = 50; U2, n = 41; U3, n = 16; U4, n = 46; U5, n = 34. In grading by variceal diameter, overall correspondence between TUS and gastroscopy was 93% (174/187). TUS-OCCA greatly improved rates of detection of varices at the cardia and fundus, offering a new method by which diagnosis and quantitative grading may be achieved and affording an excellent, non-invasive approach to dynamic follow-up.

Keywords: Cellulose; Doppler; Grading; Transabdominal ultrasound; Varices.