Localize the optic neuropathy

March 15, 2011

Typical demyelinating optic neuritis is diagnosed by first localizing the problem.

A typical case of how the diagnosis of optic neuritis is reached and managed was discussed by Eric Eggenberger, DO, during the annual meeting of the American Academy of Ophthalmology.

Case study

The vision levels in the right and left eyes, respectively, were 20/20 and 20/100. The left eye had an RAPD. The optic discs were normal bilaterally; the visual fields were normal in the right eye, while the left eye had central depression. The findings on magnetic resonance imaging (MRI) were subtle, with lesions in the white matter in the periventricular region.

The definition of optic neuritis that Dr. Eggenberger used was acute inflammatory or demyelinating disease that is idiopathic or associated with a demyelinating disease such as multiple sclerosis (MS) and not including infectious causes of optic neuropathy or other inflammatory causes such as sarcoid.

He outlined the steps for ophthalmologists to take when confronted with patient with a neuro-ophthalmic problem.

"First, you have to localize," said Dr. Eggenberger, professor and vice chairman, Department of Neurology, Michigan State University, East Lansing. "You know from the history and the examination that the patient has an optic neuropathy.

"Second, consider the differential diagnosis and consider the mimics in addition to optic neuritis," he continued.

"Third, there is one acute treatment decision to make, that is, whether or not to prescribe high-dose steroids," Dr. Eggenberger said.

"Fourth, obtaining an MRI [study] is essential in the management of these patients to stratify the risk of MS over time," he said.

"And fifth, there is one chronic treatment decision to make, that is, to decide whether or not to institute immunomodulation therapy, which may be best determined in consultation with a neurologist," he added.