Korean J Radiol.  2012 Feb;13(Suppl 1):S12-S16. 10.3348/kjr.2012.13.S1.S12.

EUS Elastography: Advances in Diagnostic EUS of the Pancreas

• Lee TH
• Cha SW
• Cho YD

• KMID: 1372862
• DOI: http://doi.org/10.3348/kjr.2012.13.S1.S12

Abstract

Elastography is an imaging modality for the evaluation of tissue stiffness, which has been used for the analysis of superficial organs, such as those of the breast and prostate. The measurement of tissue elasticity has been reported to be useful for the diagnosis and differentiation of tumors, which are stiffer than normal tissues. Endoscopic ultrasonography elastography (EUS-EG) is a promising imaging technique with a high degree of accuracy for the differential diagnosis of solid pancreatic tumors. Recent introduction of second generation EUS-EG allows for the quantitative analysis of tissue stiffness. Here, we review our knowledge and preliminary experience with the use of EUS-elastography for the diagnosis of pancreatic disease.

Keyword

Endoscopic ultrasonography elastography; Solid pancreatic tumors

MeSH Terms

Diagnosis, Differential
Elasticity Imaging Techniques/*methods
Endosonography/*methods
Humans
Pancreas/*ultrasonography
Pancreatic Diseases/*ultrasonography
Sensitivity and Specificity

Figure

• 

  Fig. 1 Principles of real-time tissue elastography. When model in which hard springs and soft springs are one-dimensionally connected is compressed, hard springs are negligibly deformed, but soft springs are markedly deformed. Same type of information is provided when sound wave passes through tissues that vary in hardness. This difference in deformation results in differences in displacement among areas, and amount of distortion obtained by spatial differentiation of this displacement distribution provides elasticity information.

• 

  Fig. 2 Quantitative analysis of pancreatic cancer using EUS elastography. Two different areas (A and B) from region of interest were selected for quantitative elastographic analysis. Area A is representative area of mass and included the biggest possible area of the tumor. Area B refers to soft (red) peripancreatic reference area outside tumor. Quotient B/A (strain ratio) is considered as measure of elastographic evaluation.

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  Fig. 3 EUS elastography of normal pancreas EUS. Elastographic imaging of normal pancreas is characterized by uniform, homogenous green color distribution (representing intermediate stiffness).

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  Fig. 4 EUS elastography of pancreatic cancer. Elastographic imaging of pancreatic cancer is characterized by heterogeneous blue color distribution (representing hard stiffness).

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