Purchase this article with an account.
Carlos E. Mendoza, Natalie Erlich-Malona, Nimesh Patel, Caitlin Monaco, Emily Cole, Thomas Hedges; Distinguishing Ischemic Optic Neuropathy from Optic Neuritis by Ganglion Cell Analysis. Invest. Ophthalmol. Vis. Sci. 2016;57(12):3393.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Optic neuritis (ON) and nonarteritic ischemic optic neuropathy (NAION), two of the most common optic neuropathies in adults, are often difficult to distinguish from one another at initial presentation. Our aim was to determine whether an altitudinal pattern of ganglion cell loss, as measured by Optical Coherence Tomography (OCT), can be used to distinguish NAION from ON during the acute phase, and whether the speed or severity of ganglion cell loss differs between the two diseases.
We performed a retrospective, case-control study of 44 patients (50 eyes) with ON or NAION and 44 age-matched controls (50 eyes). All subjects had retinal imaging with HD-OCT. NAION and ON patients had OCT imaging at presentation and four consecutive follow-up visits. Controls had OCT imaging at one point in time. Mean ganglion cell complex (GCC) thickness, mean retinal nerve fiber layer (RNFL) thickness, and GCC altitudinal difference were compared between NAION and ON patients at each time point and between disease and control subjects using unpaired t-tests.
Mean time from onset to presentation was 11 days for both NAION and ON. There was a significantly greater altitudinal difference in GCC thickness in NAION patients than ON patients at all time points (p=0.01 – 0.049). Mean GCC thickness was decreased at 0-2 weeks in both NAION and ON compared to controls (p<0.001). Mean RNFL thickness was increased in NAION at 0-2 weeks compared to controls (p=0.038) and did not significantly differ between ON and controls at 0-2 weeks. GCC thickness was significantly decreased in NAION compared to ON only at 16+ weeks (p=0.036). RNFL thickness was significantly increased in NAION compared to ON at 3-4 weeks, but did not differ significantly at any other time point.
Altitudinal difference in GCC thickness, as seen with OCT, is significantly greater in NAION than in ON, representing a key factor in distinguishing one disease from the other. Altitudinal loss of ganglion cells supports a diagnosis of NAION, whereas ON is characterized by more diffuse loss. Significant GCC thinning can be observed in both ON and NAION within two weeks of onset, confirming evidence that cell death begins early and must be addressed as quickly as possible.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.
Altitudinal Difference in GCC Thickness.
A-C: OCT analysis at 4 weeks of a patient with NAION. D-F: OCT analysis at 3 weeks of a patient with ON.
This PDF is available to Subscribers Only