Use of Optical Coherence Tomography As a Diagnostic Tool for Suspected Multiple Sclerosis in a Tertiary Center

Background:

Multiple Sclerosis (MS) is the leading cause of nontraumatic neurological disability among young adults. However, early accurate diagnosis and treatment of MS can lead to decreased clinical and radiologic progression of disease over time. Optical Coherence Tomography (OCT), which evaluates optic nerve integrity, has shown potential as a noninvasive aid for identifying abnormalities consistent with MS. However, the reliability and usefulness of OCT for this purpose has not been fully investigated. 

Objectives:

This study sought to characterize the use of OCT in evaluation of suspected MS at a tertiary care institution. 

Methods:

A retrospective chart review is underway, evaluating the 2,231 new patients evaluated by MS specialists between June, 2013 and Fall 2015 at the Johns Hopkins University MS Center, a tertiary care center in Baltimore, Maryland. Patients identified as not having at least possible MS were excluded from analysis. Detailed patient characteristics were identified, recorded, and analyzed using descriptive statistics. 

Results:

1486 charts have been evaluated to date; of these patients, 832 were removed from analysis because the patient was not being evaluated for possible MS or because MS was not a diagnostic consideration at the end of the first consultation. The average age (± standard deviation) was 46.4 ± 12.6 years; 485 (74%) were female. 371 (56%) were evaluated with OCT. Of these patients, 130 (35%) had an abnormal OCT result. The reason the scans were abnormal included average retinal nerve fiber layer (RNFL) thickness <5^th percentile (53 patients), an interocular difference in RNFL > 10 microns (44 patients), RNFL in one or more quadrants <5^th percentile (36 patients), or ganglion cell/inner plexiform layer thickness <5^th percentile (62 patients), with some patients meeting multiple criteria. The chart review is expected to be complete by May, 2015.

Conclusions:

Many MS specialists are ordering OCTs in this tertiary care center as part of the diagnostic workup for suspected MS, and nearly half of the patients appear to have abnormalities on OCT using a fairly conservative definition for abnormality. Whether OCT provides additional diagnostic certainty is not yet well established but will be explored in ongoing investigations.