A method for rendering a deformable object. The method includes: obtaining a 3D volumetric voxel dataset of a region, such region having therein an object to be rendered; building a tree hierarchical structure for the obtained volumetric dataset, such tree structure blocks as the nodes of a primary tree hierarchy and bricks being those blocks stored as textures in a video memory; augmenting the primary tree hierarchical structure with maximum and minimum values of the data contained within a block; creating a neighborhood tree hierarchy having for each leaf block of the neighborhood tree hierarchy a reference to the neighboring leaf blocks in the neighborhood tree hierarchy as well as references to neighboring bricks in the neighborhood tree hierarchy; updating the information about minimum and maximum in the primary tree hierarchy by saving for each block the minimum and maximum of the neighboring blocks; and rendering the leaf blocks in visibility order.