Aberrant gastric venous drainage and associated atrophy of hepatic segment II: computed tomography analysis of 2021 patients.

Purpose: To investigate the prevalence and patterns of aberrant gastric venous drainage and associated atrophy of the hepatic segment on contrast-enhanced computed tomography (CT).

Methods: Two radiologists retrospectively reviewed contrast-enhanced CT images from 2021 patients who underwent cone-beam CT-guided chemoembolization between January 2013 and December 2018. They determined the presence or absence of an aberrant gastric vein(s) and its drainage site by consensus, and qualitatively analyzed the presence or absence of atrophy of segments II or III. In cases of disagreement between the two reviewers regarding the presence of atrophy, quantitative analysis was performed using dedicated software.

Results: A total of 31 aberrant right gastric veins were revealed on CT (1.5%), most of which drained into P2 (n = 8), the S2/3 border zone (n = 8), S2 (n = 6), or S4 (n = 5). An aberrant left gastric vein was observed in 21 (1.0%) patients, and P2 was the most common drainage site (n = 13) in these patients. Atrophy of segment II was more frequently observed among patients with aberrant gastric veins than among those without (26.9% versus 4.1%; p < 0.001). In addition, an aberrant gastric vein draining into P2 was most frequently accompanied by segment II atrophy (47.6%).

Conclusion: Aberrant right and left gastric veins were observed in 1.5% and 1.0% of patients, respectively. Atrophy of segment II was frequently observed in patients with aberrant gastric veins, especially those that drained into P2.