Intrahepatic portosystemic venous shunt is a rare vascular anomaly that can occur congenitally or iatrogenically, leading to hyperammonemia and neurological complications such as hepatic encephalopathy. This report presents the case of a woman in her early 70s who developed recurrent episodes of altered consciousness following hepatobiliary surgery. Subsequent magnetic resonance angiography revealed an intrahepatic portosystemic venous shunt, and the patient underwent successful treatment with percutaneous transhepatic portal vein embolization. After treatment, her symptoms resolved completely, and she remained asymptomatic during an 8-month follow-up period. This report underscores the importance of considering intrahepatic portosystemic venous shunt in the differential diagnosis of postoperative neurological symptoms. Our findings suggested that percutaneous transhepatic portal vein embolization was effective in managing this case, leading to symptom resolution and sustained improvement during follow-up. Although this approach appears promising, further investigation is needed to establish its broader applicability. Early detection and appropriate management may help improve patient outcomes in selected cases.