Elastography and ultrasound image processing for the diagnostic, preventive and therapeutic approach of chronic hepatitis and cirrhosis

Purpose: This study compares two methods of liver elasticity determination, Shear Wave Elasticity (SWE) and Trancient Elastography (VCTE). Images will be provided by a group of patients with chronic parechymal liver diseases which will be compared against histological liver biopsy findings of the same patients.

Material and methods:

SWE: All SWE measurements are performed in the right lobe of the liver using an appropriate intercostal space.

Every patient is examined by two examiners, using the same methods, in order to estimate the Inter-Observer variability.

Each examiner performs two measurements on each patient using the same method to estimate the Intra-Observer variability.

VCTE: Anthropometric measurements at the time of SWE and TE should include information from patient's record about the type of liver disease and Histological evaluation of liver biopsies.

Results: There was a statistically significant difference (p < 0,01) between elastography values of normal and diseased subjects with both VCTE and SWE methods. There was a good correlation when the values of the two methods were compared between each other and each one with the liver biopsy, where available. In addition, intra- and inter-observer variability was low with both methods, if the adequate strict protocol of study was applied. VCTE showed 82.3% sensitivity and 68.2% specificity in diagnosing liver cirrhosis at a cut-off value of 8.9 kPa.SWE showed 88.5% sensitivity and 74.2% specificity in diagnosing liver cirrhosis at a cut-off value of 8.9 kPa.

Conclusion: Although patients are few, it was clearly shown that VCTE and SWE can definitely differentiate normal from fibrotic liver tissue. There is also differentiation with SWE between F1-F2 stages of fibrosis and F3-F4 appearing more evident comparing with discrimination offered by VCTE (Fibroscan). More patients are needed to investigate whether VCTE and SWE are able to differentiate between various stages of fibrotic liver disease.