Variations of Balloon-occluded Retrograde Transvenous Obliteration (BRTO): Balloon-occluded Antegrade Transvenous Obliteration (BATO) and Alternative/Adjunctive Routes for BRTO.

Alternative routes for transvenous obliteration are often sought in the management of gastric varices, as well as in the management of other nongastric varices (ectopic varices) such as duodenal and mesenteric varices. These alternative routes can be classified into A-portal venous access routes and B-systemic venous access routes. Anecdotally, alternative routes are more commonly required with duodenal and mesenteric varices compared with gastric varices. Twelve percent (2-19%) of patients with gastric varices require alternative/adjunctive variceal access routes. The most common alternative route described for transvenous obliteration of gastric varices is the percutaneous transhepatic route, which is commonly referred to in the Japanese literature as percutaneous transhepatic obliteration (PTO). The percutaneous transhepatic obliteration route can be performed alone or in combination with the more traditional balloon-occluded retrograde transvenous obliteration (BRTO) transrenal route. Percutaneous transhepatic obliteration by itself is successful in 44-100% of cases for obliterating gastric varices and is rarely unsuccessful when it is combined with BRTO. Other alternative routes are less commonly described and as a result, their clinical outcomes are relatively anecdotal. However, they are technically more challenging and are less commonly successful. These routes include, but are not confined to transphrenic, transileocolic, trans-TIPS (transvenous intrahepatic portosystemic shunt), transgonadal, transazygous, and transrenal capsular vein approaches.