LV Geometrical Metrics

Warning

This module is still under development. Changes might occur!

• Radial Distance and Radial Length
  • Radial metrics
    • Radial Distance
      • Fixed vs Moving vector
    • Radial Length
      • Fixed vs moving centers
  • Comparing Radial Metrics
    • Comparing thickness between speckles and their effect
    • Comparing Radial metrics at different locations of the geometry:
• Wall Thickness
  • Computing thickness
    • Radial Length vs Radial Distance
  • Comparing Wall Thickness metrics
    • Effect of different speckle thickness
    • Comparing Wall Thickness at different locations of the geometry:
• Longitudinal Distance
  • Longitudinal Distance
    • ‘Extremes’ vs ‘Estimate apex and base’
  • TODO: Using longitudinal distance
• Longitudianl Length
  • Longitudinal Length
  • Global longitudinal length:
• Circumferential Length
  • Circumferential Length
  • Global circumferential length (TODO)

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Definitions for Left Ventricle Metrics

Recognizing the different definitions and usage of echocardiographic quantification of the left ventricle, this section aims to provide information about basic definitions and assumptions used in this project. Our implementation considers the usage of high-quality meshes, with minimal noise and high-fidelity geometry, allowing for high-precision computations, rather than simplified assumptions used in the literature. Is important to understand that, currently, there is no consensus regading 3D speckle tracking. Consequently, we have decided to follow some standard practices for 2D speckle tracking proposed by the European Association of Echocardiography in 2015 [1] while also implementing different approaches that let’s the user decide how the final metrics are computed.

Geometrical Metrics (Geometrics):

• Radial distance: Perpendicular distance from Endo/Epi surfaces to normal vector.

• Radial length: Magnitude of vector from Endo/Epi surface to a specified center located at ‘k’ height on longitudinal line. The ‘k’ height is based on a percentage from Apex to Base representing the corresponding speckle height at longitudinal line.

• Wall thickness: Distance between Epicardium and Endocardium surfaces (can be computed based on radial distance or radia length).

• Longitudinal distance: Euclidean distance between Apex and Base reference nodes.

• Longitudinal length: Curvature length of Endo/Epi surfaces along longitudinal axis.

• Circumferential length: Curvature length of Endo/Epi surfaces along circumferential axis.

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References

• [1] Definitions for a common standard for 2D speckletracking echocardiography: consensus documentof the EACVI/ASE/Industry Task Force tostandardize deformation imaging