Evaluation of liver and splenic stiffness by acoustic radiation force impulse for assessment of esophageal varices.

Abstract

Background: In routine clinical practice, assessment of portal hypertension (PHT) among patients with liver cirrhosis is done by a upper gastrointestinal endoscopy (UGIE); however, its invasive nature limits its use. Recent advances in ultrasound imaging make it possible to evaluate the tissue stiffness of the liver and spleen reflecting the severity of underlying fibrosis. Liver stiffness and spleen stiffness can be used to predict the presence of esophageal varices/PHT among cirrhotic patients.

Aim: To predict the presence or absence of esophageal varices by measuring the stiffness of the liver and spleen by ultrasonography (USG)-based acoustic radiation force impulse (ARFI).

Methods: This cross-sectional study included 90 subjects with liver cirrhosis. Liver and splenic stiffness were measured along with the USG abdomen, UGIE and aspartate aminotransferase to platelet ratio index (APRI).

Results: Liver and spleen stiffness were significantly higher in cirrhotic patients compared to chronic hepatitis B. The best cut-off value of liver stiffness (LS) obtained by the receiver operating characteristic (ROC) curve was 2.16 m/s for predicting esophageal varices (AUROC 0.78, p 0.0002). The best cut-off value of splenic stiffness (SS) obtained by the ROC curve was 3.04 m/s for predicting esophageal varices (AUROC 0.698, p 0.0274). When both LS and SS were taken together, the accuracy in predicting esophageal varices increased to 92.22%. An equation to predict "esophageal varices = (0.225 LS + 0.377SS) - 0.555" was derived.

Conclusion: LS and SS values of ≥ 2.16 m/s and 3.04 m/s, respectively, predict esophageal varices independently; however, combined assessment is better with 92% accuracy.