Morphometry

Depending on the parameter, its computation can be performed

• In 3D, on a volume
• In 2D, from orthoslices of a 3D volume and integrated in a global result
• In 2D, from independant 2D images

Correspondance with the ASBMR nomenclature

These parameters have a general scientific meaning. Some of them correspond to a structural parameter relevant for the American Society for Bone and Mineral Research members (ASBMR). In these cases, a reference to the ASBMR standardized nomenclature [1], [2] is given in the following table. The documentation of the output class object (for example, ObjectImageRatioMsr) indicates the generic ImageDev abbreviation inside square brackets. $$\begin{array}{|l|l|l|l|} \hline \textbf{ImageDev Algorithm} & \textbf{ImageDev Abb.} & \textbf{ASBMR Name} & \textbf{ASBMR Abb.} \\ \hline \textbf{ObjectVolume} & \mbox{V} & \mbox{Bone Volume} & \mbox{BV}\\ \hline \textbf{TotalImageVolume} & \mbox{TV} & \mbox{Tissue Volume} & \mbox{TV}\\ \hline \textbf{ObjectBoundaryArea} & \mbox{S} & \mbox{Bone Surface} & \mbox{BS}\\ \hline \textbf{TotalImageBoundaryArea} & \mbox{TS} & \mbox{Tissue Surface} & \mbox{TS}\\ \hline \textbf{AverageObjectAreaPerSlice3d} & \mbox{Ar} & \mbox{} & \mbox{}\\ \hline \textbf{AverageObjectCountPerSlice3d} & \mbox{N} & \mbox{} & \mbox{}\\ \hline \textbf{ObjectImageRatio} & \mbox{IR = V/TV} & \mbox{Trabecular Bone Volume} & \mbox{BV/TV}\\ \hline \textbf{ObjectSpecificSurface} & \mbox{OSS = S/V} & \mbox{Bone Surface to Volume ratio} & \mbox{BS/BV}\\ \hline \textbf{ObjectSurfaceDensity} & \mbox{OSD = S/TV} & \mbox{Bone Surface Density} & \mbox{BS/TV}\\ \hline \textbf{PorosityPercentage3d} & \mbox{Po} & \mbox{Closed Porosity} & \mbox{Po}\\ \hline \textbf{FragmentationIndex} & \mbox{FI} & \mbox{Trabecular Bone Pattern Factor} & \mbox{Tb.Pf}\\ \hline \textbf{StructureModelIndex3d} & \mbox{SMI} & \mbox{} & \mbox{}\\ \hline \textbf{AverageObjectThickness3d} & \mbox{Th} & \mbox{Trabecular Thickness} & \mbox{Tb.Th}\\ \hline \textbf{AverageSpaceThickness3d} & \mbox{Sp} & \mbox{Trabecular Separation} & \mbox{Tb.Sp}\\ \hline \textbf{ObjectLinearDensity3d} & \mbox{Dn} & \mbox{Trabecular Number} & \mbox{Tb.N}\\ \hline \textbf{DegreeOfAnisotropy} & \mbox{DA} & \mbox{} & \mbox{}\\ \hline \end{array}$$

How to use a mask

Some algorithms take a mask image as a parameter which defines an area of interest in 2D or a volume of interest in 3D. For algorithms working on both types of image, the term "volume of interest" is mainly used, even when it may represent an area of interest in case of a 2D input. If no mask image is set (default), then the computation is performed on the entire input image. When a mask image is provided, the input image is filtered similarily to using a MaskImage algorithm and the result is computed only on the specified regions (where the mask value is not equal to 0).

References:

• [1] A.M.Parfitt, J.E. Compston, M.K.Drezner, F.H.Glorieux, J.A.Kanis, H.Malluche, P.J.Meunier, S.M.Ott, and R.R.Recker. "Bone histomorphometry: Standardization of nomenclature, symbols, and units". Journal of Bone and Mineral Research, vol. 2, pp. 595-610, 1987.
• [2] D.W.Dempster, M.K.Drezner, F.H.Glorieux, J.A.Kanis, H.Malluche, P.J.Meunier, S.M.Ott, R.R.Recker and A.M.Parfitt. "Standardized Nomenclature, Symbols, and Units for Bone Histomorphometry: A 2012 Update of the Report of the ASBMR Histomorphometry Nomenclature Committee". Journal of Bone and Mineral Research, vol. 28, no. 1, pp. 2-17, 2013