HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Full Text (PDF) Correspondence: Submit a response Alert me when this article is cited Alert me when Correspondence are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Ratchford, J. N. Articles by Kerr, D. A. PubMed PubMed Citation Articles by Ratchford, J. N. Articles by Kerr, D. A.

Optical coherence tomography helps differentiate neuromyelitis optica and MS optic neuropathies

From the Department of Neurology (J.N.R., M.Q., P.A.C., D.A.K.), Johns Hopkins University School of Medicine, Baltimore, MD; Departments of Neurology and Ophthalmology (A.C., T.F., E.F.), University of Texas Southwestern Medical Center, Dallas, TX; and Departments of Neurology and Ophthalmology (L.J.B.), University of Pennsylvania School of Medicine, Philadelphia, PA.

Address correspondence and reprint requests to Dr. Douglas A. Kerr, Johns Hopkins University School of Medicine, 600 N. Wolfe St., Pathology 627, Baltimore, MD 21287 dkerr{at}jhmi.edu

Objective: To evaluate the retinal nerve fiber layer (RNFL) thickness and macular volume in neuromyelitis optica (NMO) spectrum patients using optical coherence tomography (OCT).

Background: OCT can quantify damage to retinal ganglion cell axons and can identify abnormalities in multiple sclerosis and optic neuritis (ON) eyes. OCT may also be useful in the evaluation of patients with NMO.

Methods: OCT and visual function testing were performed in 26 NMO spectrum patients with a history of ON, 17 patients with isolated longitudinally extensive transverse myelitis (LETM) without ON, 378 patients with relapsing–remitting multiple sclerosis (RRMS), and 77 healthy controls at 2 centers.

Results: Substantial RNFL thinning was seen in NMO ON eyes (63.6 µm) relative to both RRMS ON eyes (88.3 µm, p < 0.0001) and control eyes (102.4 µm, p < 0.0001). A first episode of ON was estimated to cause 24 µm more loss of RNFL thickness in NMO than RRMS. Similar results were seen for macular volume. ON also was associated with more severe visual impairment in NMO spectrum patients than in RRMS patients. Eyes in the LETM group and unaffected NMO eyes were not significantly different from controls, though conclusions about these subgroups were limited by small sample sizes.

Conclusions: Optical coherence tomography (OCT) shows more severe retinal damage after optic neuritis (ON) episodes in neuromyelitis optica (NMO) than in relapsing–remitting multiple sclerosis. Identification of substantial retinal nerve fiber layer loss (>15 µm) after ON in a non–multiple sclerosis patient should prompt consideration of an NMO spectrum condition. OCT may be a useful tool for the evaluation of patients with NMO.

Abbreviations: CI = confidence interval; ETDRS = Early Treatment Diabetic Retinopathy Study; IgG = immunoglobulin G; LETM = longitudinally extensive transverse myelitis; MS = multiple sclerosis; NMO = neuromyelitis optica; OCT = optical coherence tomography; ON = optic neuritis; RNFL = retinal nerve fiber layer; RRMS = relapsing–remitting multiple sclerosis.

Supported by the National Multiple Sclerosis Society and the Nancy Davis Foundation.

Disclosure: Author disclosures are provided at the end of the article.

Received November 13, 2008. Accepted in final form April 17, 2009.