1. A method of automatically reconstructing a model of a branching tubular organ via a hybrid approach that defines endoluminal airway surfaces from a chest scan and segmentation data, the model being used to provide guidance to a user of an endoscope, the method comprising: receiving three-dimensional (3D) digital image data of a branching tubular organ and anatomy surrounding the branching tubular organ; automatically computing, on a processor, a conservative segmentation of the branching tubular organ from the digital image data; generating a collection of peripheral branches not identified in the conservative segmentation based on approximating cross sections of the peripheral branches shown in the digital image data as ellipses; adding or extending at least one of the peripheral branches identified in the generating step to the conservative segmentation; automatically constructing, on the processor, accurate endoluminal surfaces of the organ segmentation, including any of the peripheral branches that were added or extended to the conservative segmentation; producing a reconstructed graphical image as a comprehensive model of the branching tubular organ including the at least one of the peripheral branches that were added or extended by the adding step, wherein the at least one of the peripheral branches that were added or extended is capable of being manipulated; and displaying, on a display device, the comprehensive model containing the accurate luminal surfaces through the branching tubular organ including the added or extended peripheral branches.