Repeatability of a protocol to evaluate the effect of storage on the mechanical properties of the kidney in-vitro

Redouane Ternifi , Jean-Luc Gennisson (1) , Mickaël Tanter (2) , Philippe Beillas

1 LOA - Laboratoire Ondes et Acoustique (UMR 7587)
2 IL - Institut Langevin - Ondes et Images (UMR7587)

In biomechanical testing protocols of soft tissue, specimens may have to undergo freezing or other conservation methods, which could affect their mechanical properties. In order to evaluate the effects of conservation techniques, an experimental protocol based on shear wave elastography - which provides an assessment of shear modulus (μ) – was developed and applied to porcine kidneys. First, the organ is pinned onto a polystyrene plate. Then the plate then used to position the organ with respect to an ultrasound probe. This study provides an estimation of the repeatability of μ after repositioning a single kidney, and evaluates the effects of storing 8 fresh kidneys at room temperature for two days. μ were computed rectangular windows centred on the image and moving along the organ depth. When repositioning the organ, μ was more repeatable in the cortex near the capsule than in the central regions of the organ. These regions were also more inhomogeneous and imaging was not always possible due to ultrasound penetration issues. The cortex near the capsule was softer than the central regions including pyramids (e.g. 6.1±2.4kPa at 10% depth vs. 9.3±3.5kPa at 30% depth, n=8). Storage for two days had no significant effect on these values (p>0.25).

Mots clés: Experimental protocol; Imaging; Elastography; Shear modulus

Domaines: Acoustique [physics.class-ph]

Redouane Ternifi, Jean-Luc Gennisson, Mickaël Tanter, Philippe Beillas. Repeatability of a protocol to evaluate the effect of storage on the mechanical properties of the kidney in-vitro. Acoustics 2012, Apr 2012, Nantes, France. ⟨hal-00811285⟩