Optic Neuritis-MRI

Optic neuritis is defined as inflammation of the optic nerve. It is one of the causes of acute loss of vision associated with pain. Optic neuritis can be the initial episode for a patient who will subsequently develop multiple sclerosis.  Thin fat-suppressed T2-weighted images, such as short tau inversion recovery sequences, through the optic nerves may show characteristic high-signal intensity foci in the minimally or nonexpanded nerve. These lesions frequently enhance following intravenous contrast administration, which is not seen in a healthy optic nerve.  In our case DWI was also used which shows expanded left optic nerve with bright signal on DWI and enhancement on CEMRI. In this patient MRI brain had no evidence of MS.

Optic Perineuritis-Imaging

Optic perineuritis is an uncommon variety of orbital inflammatory disease that is distinct from demyelinating optic neuritis. In contrast to those with optic neuritis, patients with optic perineuritis are often older at onset and are more likely to show sparing of central vision. Magnetic resonance imaging scans demonstrate enhancement around, rather than within, the optic nerve. Response to corticosteroids is more dramatic than in patients with optic neuritis, and patients are more likely to experience recurrence after stopping treatment.

MRI usually shows Perineural enhancement and “streaky” fat with or without extraocular muscle enhancement. This patient improved dramatically with steroids.

Dr.Sumer K Sethi, MD
Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers
Editor-in-chief, The Internet Journal of Radiology
Director, DAMS (Delhi Academy of Medical Sciences)