Figure 5: Imaging test showing ON. A. MRI Coronal cut. Regular thickening of the left eye proving ON (arrow). B. Another coronal cut of a different patient above orbital apex in the sequence STIR- FLAIR. Left optic nerve hyperintensity, enhancement and swelling is remarkable comparing with the right one. C. Sagittal cut of MRI in a male of 14 years old with a clinic diagnosis of ON: T1 sequence with fat suppression, showing regular hyperintensity and thickening of all the optic nerve segments between the eye and chiasm. D. Computed tomography (CT) without contrast, showing regular and diffuse thickening of the right optic nerve (arrow). Courtesy of Spanish Society of Ophthalmology.