Traumatic brain injury detection

Apparatus for the non-invasive in-vivo determination of changes in tissue of the optic nerve in a biological subject, said apparatus comprising:

• i. a laser source for generating an excitation laser beam;
• ii. an optical system including a fundus camera operatively associated with the laser source for use in obtaining a fundus image for illuminating the optic nerve of a subject with the excitation laser beam;
• iii. a detector operatively associated with the optical system and configured to detect a Raman spectrum from the optic nerve and/or surrounding cerebral spinal fluid;
• and
• iv. a processor operable to compare the detected Raman spectrum to at least one reference Raman spectrum of an optic nerve and/or surrounding cerebral spinal fluid of a healthy subject, the reference spectrum corresponding 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, wherein the processor is operable to compare the detected Raman spectrum to the reference Raman spectrum in a non-fingerprint region of the spectrum from 2000 cm−1 to 3500 cm−1, wherein the optical system further comprises:
• a short pass dichroic mirror filter configured to transmit visible light for obtaining the fundus image whilst reflecting laser and Raman scattered light;
• and a long pass dichroic mirror filter configured to reflect light emitted from the excitation laser source and to transmit resonance Raman scattered light.