Assessment of Wallerian degeneration by automated image analysis

Axonal degeneration is a hallmark of both developmental and pathological events. Degenerating axons appear as either interruptions in the cytoskeletal network or aggregates along the axon. Since manual quantification of degeneration events is cumbersome and time consuming, automating this process promises to expedite drug discovery as treatment for axonal injury or neurodegenerative disorders such as Alzheimer´s disease. In this paper we present a multiscale approach to segment the degenerative features from the intact axonal structure. The segmentation involves delineation of the axons and detection of blebbing in the axonal cytoskeleton. The solution makes use of tools from morphology and scale analysis. The delineated set of degenerative features is then quantified with respect to the overall neuronal mass and the mass of the intact axons and a degeneration index is derived.