2D Shear Wave Elastography of Liver in Patients with Primary Extrahepatic Portal Vein Obstruction

Clinical application of liver stiffness measurement in patients with cavernous transformation of portal vein

The clinical outcomes differ between patients with cavernous transformation of the portal vein (CTPV) with and without cirrhosis. Therefore, invasive liver biopsy may be needed for the differential diagnosis of patients with CTPV with or without cirrhosis. The present study aimed to investigate the diagnostic efficacy of liver stiffness measurements (LSM) for the prediction of cirrhosis in patients with CTPV. A total of 20 patients with CTPV, 34 with chronic hepatitis B (CHB)-related cirrhosis and 20 healthy volunteers, were retrospectively recruited in the study. CTPV was diagnosed with contrast-enhanced computed tomography (CT) and ultrasound for the abdomen. LSM values were detected for each patient, while liver biopsy was performed in each patient in the CTPV and cirrhosis groups. The results demonstrated that LSM values were significantly lower in the CTPV group (12.5 kPa; range, 6.8-21.5 kPa) compared with the CHB-related cirrhosis group (21.0 kPa; range, 15.5-27.2 kPa; P=0.017). However, this was still higher compared with healthy volunteers (4.9 kPa; range 4.0-5.8 kPa; P<0.001). In addition, CTPV patients with cirrhosis (17.7 kPa; range, 13.9-30.8 kPa) exhibited significantly increased LSM values compared with those without cirrhosis (6.4 kPa; range, 5.7-7.8 kPa; P<0.001). Furthermore, LSM values in CTPV patients without cirrhosis were slightly higher compared with those of healthy volunteers (P=0.003), while no statistically significant difference was observed in LSM between CTPV patients with cirrhosis and CHB-related cirrhosis group. These findings indicated that LSM values could be used for the differential diagnosis of CTPV patients with or without cirrhosis. However, further validation studies are needed.

Splenic stiffness and platelet count to predict varices needing treatment in pediatric extrahepatic portal vein obstruction

BACKGROUND

Surveillance endoscopy to detect varices needing treatment (VNT) is important to prevent bleeding and morbidity in portal hypertension. In adult and pediatric cirrhosis, platelet count and liver stiffness measurement (LSM) are useful in selecting patients for endoscopy. Such recommendations do not exist for extrahepatic portal vein obstruction (EHPVO). Splenic stiffness measurement (SSM) has been studied in adult and pediatric EHPVO with conflicting results and methodological errors. This study evaluates the role of platelet counts and SSM to predict VNT and bleeding in pediatric EHPVO while comparing LSM and SSM between pediatric EHPVO and controls.

METHODS

One hundred and seven children (55 with EHPVO and 52 controls) were recruited. Clinical, biochemical, hematological, and radiographic parameters of all children were noted. All children with EHPVO underwent endoscopy.

RESULTS

Of the 55 children with EHPVO, 48 (87.3%) had VNT. There was no difference in the platelet counts (85,000/mm³ vs. 120,000/mm³, p = 0.58) and SSM (3.62 vs. 3.19, p = 0.05) between EHPVO children with VNT and those without. They had poor sensitivity and specificity to predict VNT. EHPVO children with bleeding had higher SSM that those without. LSM was higher among EHPVO than among controls (1.19 vs. 1.10, p = 0.003). Those with LSM higher than controls had normal liver histology.

CONCLUSION

SSM is higher in EHPVO bleeders but SSM and platelet counts are unreliable to predict VNT in pediatric EHPVO. Surveillance endoscopies may be needed in all pediatric EHPVO until better screening strategies are available.

TRIAL REGISTRATION

Not applicable.

Measurement of splenic stiffness by 2D-shear wave elastography in patients with extrahepatic portal vein obstruction

OBJECTIVE:

To assess the accuracy of splenic stiffness (SS) measured by 2D-shear wave elastography (SWE) for predicting variceal bleeding in the patients with extrahepatic portal vein obstruction (EHPVO).

METHODS:

52 patients with EHPVO (mean age: 22.29 years; 26 each males and females) were included in the study after obtaining approval from the institute ethics committee. All patients initially underwent upper gastrointestinal endoscopy followed by ultrasonography, including 2D-SWE on the Aixplorer Supersonic Imagine scanner. The SS was measured through the anterior abdominal wall and an average of three measurements was taken. The SS was then compared with clinical symptoms, variceal grade, and other ultrasonography (USG) parameters. USG parameters were also compared with variceal grade.

RESULTS:

The mean SS was 44.92 ± 12.35 kPa. There was no significant difference in the mean SS of patients with high grade varices (44.30 kPa; n = 25) from those with low grade varices (46.91 kPa; n = 20). The ROC analysis showed a poor area under the curve of 0.477 for the prediction of high grade varices by the SS. The SS did not show any significant correlation with other ultrasonography parameters except splenic size, with which there was a weak but significant correlation. The measurement of SS by 2D-SWE was reliable and Cronbach's alpha was 0.905.

CONCLUSION:

The SS measured by 2D-SWE is not an accurate predictor of variceal grade and thus bleeding in patients of EHPVO.

ADVANCES IN KNOWLEDGE:

EHPVO is a vascular pathology with most patients showing splenomegaly and preserved liver function. Although, elastography of spleen has been shown to be useful in patients with cirrhosis for predicting portal hypertension, it does not seem to be helpful in patients with EHPVO.

Evaluation of Splenic Stiffness in Patients of Extrahepatic Portal Vein Obstruction Using 2D Shear Wave Elastography: Comparison with Intra-Operative Portal Pressure

BACKGROUND/AIMS

To compare splenic stiffness (SS) with intra-operative portal pressures (PPs) in patients of extrahepatic portal vein obstruction (EHPVO).

METHODS

Twenty-one patients (14 males; 7 females) of mean age 20.4 years with clinical and sonographic diagnosis of EHPVO were included in this approved prospective study. Endoscopy for esophageal varices (EV) was done in all patients followed by ultrasonographic 2D shear wave elastography (SWE) of spleen. Three values were taken at different areas of spleen avoiding major vessels and mean was calculated. Intra-operative PP was measured from an omental vein during proximal spleno-renal shunt surgery. The PP was compared and correlated with SS along with other parameters.

RESULTS

The mean SS was 46.04 ± 8.0 kPa and the mean PP was 33.29 ± 4.1 mmHg. There was no significant correlation between PP and SS (P = 0.61) and between grades of EV and SS (P = 0.38). Significant correlation was seen between grades of EV and PP (0.04). SS also did not show significant correlation with splenic size or duration of disease.

CONCLUSION

SS measured by 2D SWE did not correlate with PP and thus may not help in predicting gastrointestinal bleed in patients of EHPVO.