Geometrical scaling for the measurement of in-vivo human inner ear

This study is to assess the optimal process for the surface smoothing of 3D image model of in vivo human inner ear. A 3D image model of the inner ear including semicircular canals, vestibule and cochlea was reconstructed from magnetic resonance imaging data. Three smoothing methods including constrained smoothing, unconstrained smoothing and smoothsurface will be discussed. The volume of the 3D image model produced by unconstrained smoothing differed substantially from the original model volume prior to smoothing. Constrained smoothing had an uneven effect on the surface of the 3D image models. Using the smoothsurface module, we were able to obtain an optimal surface of the 3D image model of the human inner ear including the semicircular canals, vestibule and cochlea, using 10 iterations and a lambda value of 0.6. The 3D image model by smoothsurface would be worthy of reference in clinical evaluation.