Methods and apparatus are provided for analysis of 3-dimensional images of an optic nerve head surface topography. Topographic images of the optic nerve head may be analysed to define a topographic model fitted to the topographic image of the optic nerve head about a centre of analysis. The topographic model is defined using model morphological parameters, and the morphological parameters. In some embodiments, the morphological parameters may be used to detect nerve fibre damage or pathology, such as in the diagnosis of glaucoma.