1. A method for determining geometrical properties of a structure of an object of interest displayed in an image, comprising the steps of: (a) generating a deformable surface model of a surface of a training object, wherein the deformable surface model includes a mesh of triangles; (b) generating an extended deformable surface model of the training object by associating additional geometrical information to the generated deformable surface model of the training object, wherein the step of generating an extended deformable surface model includes: identifying triangles belonging to sub-parts of the training object; labeling the triangles belonging to the respective sub-parts of the training object; selecting a geometric primitive in accordance with a measurement to be carried out and a form of a selected corresponding sub-part; fitting the geometric primitive to surface elements labeled to the selected corresponding sub-part; determining a rule which defines the selected geometric primitive and a method which fits the selected primitive onto the selected corresponding sub-part; and labeling each triangle with the determined rule along with the respective sub-part label to generate an extended deformable surface model; (c) adapting the extended deformable surface model to a surface of the object of interest, such that a one-to-one point correspondence is maintained between the extended deformable surface model and the adapted extended deformable surface model; (d) determining the geometrical properties of the structure of the object of interest from the adapted extended deformable surface model according to the associated additional geometrical information; and (e) extracting at least one measurement of interest of the structure based on the determined geometrical properties.