Elastography of Diffuse Liver Disease - where are we now?

Congress:

ECR 2013

Poster Number:

C-1984

Type:

Educational Exhibit

Keywords:

Abdomen, Liver, Ultrasound physics, Elastography, Ultrasound, Technology assessment, Education, Cirrhosis, Pathology

Authors:

O. S. Jaffer, G. Yusuf, P. Sidhu; London/UK

DOI:

10.1594/ecr2013/C-1984

DOI-Link:

https://dx.doi.org/10.1594/ecr2013/C-1984

Fig. 1: Metavir histological scoring system for the assessment of liver fibrosis

Fig. 2: Ishak histological scoring system for the assessment of liver fibrosis.

Fig. 3: TE imaging with depiction of ROI within the liver parenchyma

Fig. 7: Realtime acoustic radiation force impulse measurement in a healthy volunteer....

Learning objectives

To become familiar with the various modalities currently available to quantify liver fibrosis. To appreciate the advantages and limitations of each technique To appreciate the clinical applications ultrasound elastography allows.

Background

Currently, liver biopsy to obtain histology is considered the ‘gold standard’ to quantify liver fibrosis.However, biopsy is as an invasive procedure with recognised risks, limitations and monetary costs. Complications may range from pain, to more unusual but serious complications such as intraperitoneal haemorrhage. Furthermore, there is potential for sampling errors given the heterogenous nature of fibrosis distribution and the small area sampled by a liver biopsy (approximately 1/50000th of total liver volume). Studies have shown these factors may lead to misdiagnosis in 25% and discordance...

Imaging findings OR Procedure details

The four most investigated modalities for US elastography assessment are: Transient elastography (TE), Real time tissue elastography (Hi-RTE), Acoustic radiation force impulse (ARFI) imaging and SuperSonic Imaging (SSI) (ShearWave elastography). Transient Elastography(FibroscanTM, Echosens, Paris, France) Physics: An ultrasound probe is placed in the right intercostal space and when activated emits a low frequency elastic shear wave (50Mhz). Pulse echo acquisition is then performed to follow the shear wave and measure the velocity within a predetermined region of interest.The propagation velocity of a wave through tissue...

Conclusion

There is potential for replacing invasive methods of evaluation with non-invasive modalaties. There has been significant progression in elatrography and all four modalities appear promising for the evaluation of liver fibrosis. To further the development, it would seem certain issues need consideration: (i) The inherent inadequacies of the ‘reference standard’ of liver biopsy need to be addressed. (ii) A universal protocol for image acquisition. (iii) Prospective validationof cut-off values. The advent of elastography is exciting, both in its applicationand in its potential benefit for the...

References

1.Regev A, Berho M, Jeffers LJ, et al. Sampling error and intraobserver variation in liver biopsy in patients with chronic HCV infection. Am J Gastroenterol 2002;97:2614–8 2.Sandrin L, Fourquet B, Hasquenoph JM, et al. Transient elastography: a new noninvasive method for assessment of hepatic fibrosis. Ultrasound Med Biol 2003;29:1705–13 3. Tsochatzis EA, Gurusamy KS, Ntaoula S, Cholongitas E, Davidson BR,Burroughs AK. Elastography for the diagnosis of severity of fibrosis in chronic liver disease: a meta-analysis of diagnostic accuracy. J Hepatol 2011;54:650–9 4. Talwalkar JA, Kurtz...