Background: In patients with portal hypertension, EUS reveals the presence of collateral vessels within and outside the esophageal wall such as esophageal varices, periesophageal collateral veins (peri-ECVs), paraesophageal collateral veins (para-ECVs), and perforating veins. This study retrospectively compared radial EUS images of these collateral vessels with histopathologic findings.
Methods: Four patients with esophageal varices treated by endoscopic injection sclerotherapy were studied. EUS was performed to evaluate the effects of endoscopic injection sclerotherapy. After endoscopic injection sclerotherapy, the segment of the esophagus from the esophagogastric junction to a point 5 cm proximal to junction was imaged with a 20-MHz radial scanning catheter US probe. Esophageal collateral veins outside the esophageal wall were identified as peri-ECVs (veins lateral to muscularis propria or within adventitia) and para-ECVs (veins lateral and separate from muscularis propria) along with perforating veins (veins connecting extramural collateral veins to submucosal varices). At autopsy, the esophagus with surrounding tissue was removed and cross-sectioned at 1-cm intervals from the esophagogastric junction to a point 5 cm proximal to the junction. Radial EUS images were correlated with histopathologic findings.
Results: Radial EUS after endoscopic injection sclerotherapy demonstrated peri-ECVs and perforating veins in all cases and para-ECVs in 3 cases. Based on histopathologic findings, veins associated with the esophageal wall were divided into 3 groups: those adjacent to the muscularis propria, veins separated from the wall without contact with the muscularis propria, and veins perforating the muscularis propria. All 3 groups of veins were observed in all cases. These 3 types of veins identified by histopathologic examination corresponded, respectively, to the peri-ECVs, para-ECVs, and perforating veins observed by EUS.
Conclusion: Collateral esophageal veins demonstrated by radial EUS in patients with portal hypertension correspond to collateral veins identified histopathologically. In patients with portal hypertension, EUS is useful for assessment of vascular anatomy around the esophageal wall.