New topics in the clinical use of Sonoelastography Antonio Pio Masciotra Campobasso – Molise – Italy Website YouTube channel

Echogenicity and Elasticity of tissues are quite different features!  Almost isoechoic tissues can have very different elasticity (12,0 kPa in normal parenchima Vs 21,6 kPa inside the nodule).  Isoelastic tissues (14,5 kPa) can have different echogenicity (highest in normal parenchima and intermediate to low inside the nodule). Antonio Pio Masciotra Campobasso – Molise – Italy Website YouTube channel j21nKGAhR997Ia3-QegQ New topics in the clinical use of Sonoelastography

Echogenicity and Elasticity of tissues are quite different features!  Almost isoechoic tissues can have very different elasticity (from 69,8 kPa to 147 kPa) like in this breast cancer.  Also stiffest areas in this cancer (113,5 kPa to 147,1 kPa) can have different echogenicity (at the boundary between the nodule and surrounding tissue). Antonio Pio Masciotra Campobasso – Molise – Italy Website YouTube channel j21nKGAhR997Ia3-QegQ New topics in the clinical use of Sonoelastography

Echogenicity and Elasticity of tissues are quite different features!  Almost isoechoic tissues can have very different elasticity (from 14,2 kPa to 147 kPa) like in this patient who has a fibroadenoma in the right breast and a cancer in the left breast.  Then the feature ‘Echogenicity’ has not correlations to the feature ‘Elasticity’ Antonio Pio Masciotra Campobasso – Molise – Italy Website YouTube channel j21nKGAhR997Ia3-QegQ New topics in the clinical use of Sonoelastography Feature (kPa)FibroadenomaCancer Mean stiffness37,395,2 Maximum stiffness57,1147,1 Minimum stiffness14,269,8 Standard Deviation8,017,3

Elasticity of tissues is a very important feature!  We well know that cancer and surrounding desmoplastic reaction tissue are not only far stiffer than fat (from 3,4 to 4,3 times) but also large more inhomogeneous. This latter feature is expressed by the higher Standard Deviation found in the stiffness’ values in the cancer and surrounding tissue compared to the ones found in fat tissue. It’s interesting that the features showing the most significative differences between cancer and fat are the Standard Deviation and its ratio. Antonio Pio Masciotra Campobasso – Molise – Italy Website YouTube channel j21nKGAhR997Ia3-QegQ New topics in the clinical use of Sonoelastography Feature (kPa)CancerFatRatio Mean stiffness96,723,44,2 Maximum stiffness147,139,63,7 Minimum stiffness45,613,43,4 Standard Deviation20,24,74,3

 We well know that usually fibroadenoma is somewhat stiffer than fat (from 3,4 to 4,3 times) but also little more inhomogeneous. This latter feature is expressed by the higher Standard Deviation found in the stiffness’ values in the fibroadenoma compared to the ones found in fat tissue. It’s interesting that the more significative feature in fibroadenoma Vs fat comparison is the minimum stiffness (more than 9 times higher in the fibroadenoma). Antonio Pio Masciotra Campobasso – Molise – Italy Website YouTube channel j21nKGAhR997Ia3-QegQ New topics in the clinical use of Sonoelastography Feature (kPa)Fibro adenoma FatRatio Mean stiffness39,312,23,2 Maximum stiffness50,420,22,5 Minimum stiffness30,43,29,5 Standard Deviation4,72,51,9

Echogenicity and Elasticity of tissues are quite different features!  In the same image of the cancer 3 different ROIS of isoechoic tissue are selected : the one in the circle is relatively far from the cancer, while the two within traces are near the cancer. We can see that the fibrous tissue around the cancer is stiffer than the fibrous tissue far from the cancer. Antonio Pio Masciotra Campobasso – Molise – Italy Website YouTube channel j21nKGAhR997Ia3-QegQ New topics in the clinical use of Sonoelastography Feature (kPa)Circle ROI Trace ROIS Ratio Mean stiffness24,962,8 75,3 2,5 3,0 Maximum stiffness48,3146,8 105,5 3,0 2,2 Minimum stiffness12,029,2 38,9 2,4 3,2 Standard Deviation7,626,0 14,4 3,4 1,9

CONCLUSIONS Sono-Elastography adds valuable information to the study of all organs, potentially resulting in “a virtual biopsy”. This final aim will be achieved when further improvement of Shear Wave Elastography technology (the only actually capable to quantify elasticity or stiffness) will give us the right consistency of the quantitative measurements of tissue elasticity that up todate is still lacking. Hence the RSNA initiative of ‘Quantitative Imaging Biomarkers Alliance’ applied to Sono-Elastography too. This means that if the intrinsic elasticity of the testis is 2 kPa all the measurements have to give this value, not depending on the probe’s frequency or on other variables. When this requirement will be accomplished we’ll can really establish the cutoff value between normal and abnormal tissues both in focal and in diffuse diseases. Therefore we’ll can rely on it at same extent we actually rely on the use a thermometer to check the behavior of the fever during an infection (if it’s responding to the treatment). Then let’s go on! Lessons need to be drawn from two great men of the past who had the vision to preparing for the future.

Galileo Galilei "Any problem that wants to be solved starts with curiosity." "Knowing is not enough, we must apply. Willing is not enough, we must do." Johann Wolfgang von Goethe

New topics in the clinical use of Sonoelastography Antonio Pio Masciotra Campobasso – Molise – Italy Website YouTube channel