Freiburg Neuropathology Case Conference: Progressive Optic Nerve Lesion Over a 16-Year Period

A 60-years-old female patient, first presented in 2008 with a transient visual impairment of the left eye and pathological visually evoked potentials.Magnetic resonance imaging (MRI) revealed a unilateral, concentric, enhancing lesion encasing the non-enhancing left optic nerve sheath (Fig. 1).Cerebrospinal fluid showed a mild pleocytosis with negative oligoclonal bands and no intrathecal immunoglobulin synthesis.In 2011, a second episode of transient visual impairment of the left eye occured, which spontaneously regressed.CSF diagnostics again showed pleocytosis with evidence of oligoclonal bands in the CSF, whereupon immunosuppressive therapy was initiated under the suspected diagnosis of an inflammatory CNS disease.In 2018, the patient presented with an external oculomotor nerve palsy.Imaging revealed a thickened optic nerve sheath and a progressive congestion of the optic nerve sheath over the course