Ultrasound Imaging, Classification, and Clinical Insights of Intrahepatic Congenital Portosystemic Shunts

Congenital portosystemic shunts (CPSS) are rare developmental anomalies where blood is diverted from the portal venous system and liver to the systemic circulation. This case series examines the sonographic imaging features, classification, ultrasound-derived shunt ratios, and clinical outcomes of CPSS in nine children (five females, four males) admitted to our institution between 2015 and 2022. Each shunt was initially classified according to the Parks classification system and monitored through serial ultrasound exams to assess changes over time. In addition to sonographic imaging, data on clinical presentations, laboratory results, shunt ratios, and time to shunt closure were also collected and analyzed. Most cases observed in this study were of Type 3 CPPS, the most common form of these shunts. In cases where the shunt ratio was measured, findings showed a gradual decrease in shunt ratios alongside reductions in blood ammonia levels until spontaneous closure was achieved. High shunt ratios and Type 4 shunts emerged as predictors for delayed or absent shunt closure, suggesting a higher risk profile. Monitoring CPPS through ultrasound imaging, particularly via shunt ratio calculation, can be a valuable tool in clinical management. This ratio provides insight into the risk of complications such as hepatic encephalopathy and can help predict the timing of spontaneous closure. These findings emphasize the importance of ongoing ultrasound evaluation to gauge disease progression and assess closure potential, with ammonia levels providing a helpful adjunct for clinical correlation.