Traumatic brain injury detection

Apparatus (1) for the non-invasive in-vivo determination of changes in tissue, e.g. the myelination, of the optic nerve (ON) in a biological subject, said apparatus (1) comprising: a laser source (10) for generating an excitation laser beam (b); an optical system including a fundus camera (11) operatively associated with the laser source (10) for use in obtaining a fundus image for illuminating the optic nerve (ON) of a subject with the excitation laser beam (b); a detector (13) operatively associated with the optical system and configured to detect a Raman spectrum from the optic nerve (ON) and/or surrounding cerebral spinal fluid; and a processor provided with a computer program for comparing the detected Raman spectrum to at least one reference spectrum, the reference spectrum may correspond to the myelination of the optic nerve in a normal, healthy subject, for determining the changes in the myelination of the optic nerve of the subject based on the detecting and comparing steps from the Raman spectrum.