RETINAL EVALUATION WITH SPECTRAL DOMAIN-OPTICAL COHERENCE TOMOGRAPHY IN EYES WITH PREVIOUS OPTIC NEURITIS AND NEUROMYELITIS OPTICA SPECTRUM DISORDERS OR ANTI-MYELIN OLIGODENDROCYTE GLYCOPROTEIN ANTIDOBY ASSOCIATED DISEASE

Objectives:

To compare retinal layers thickness using Spectral Domain-Optical Coherence Tomography (SD-OCT) in patients with previous optic neuritis (ON) and neuromyelitis optica spectrum disorders (NMOSD), that have positive anti-aquaporine4 antibody (AQP4) or anti-myelin oligodendrocyte glycoprotein antibody associated disease (MOGAD), or that are negative for both IgG antibodies.

Methods:

Fourty-nine patients were included and divided into 3 groups: ON-AQP4 (n=21); ON- MOGAD (n =19) and ON double-IgG seronegative (ON-DSN, n=9). The control group had nineteen patients.

Patients were submitted to complete ophthalmic evaluation, including 24-2 standart automated perimetry and SD - OCT with acquisition of peripapillary retinal nerve fiber layer (pRNFL), macula full-thickness (mFT) and the following segmented retinal layers: macular-RNFL (mRNFL), Ganglion Cells (GCL), Inner Plexiform (IPL), Inner Nuclear (INL), Outer Plexiform (OPL), Outer Nuclear (ONL) and Photoreceptors (PhL).

The mean thickness was obtained for each layer and the visual field mean sensitivity (VFMS) was also calculated. Data were compared using GEE models and values of p<0.001 were considered statistically significant.

Results:

The difference previously observed that the OPL was thinner in the ON-AQP4 eyes than in the ON-MOGAD patients was not confirmed with strong statistical significance (p=0.04).  Yet the inner retina until the INL was thinner than controls for all three ON groups, but the measures were similar between the affected groups.

The pRNFL was thinner than controls only in the ON-AQP4 and in the ON-MOGAD eyes, but also equivalent between the two ON-groups.

The VFMS of the ON-AQP4 patients was significantly lower compared with the other two affected groups (p<0.001). All three groups had VFMS reduced versus controls (p<0.001).

Conclusion:

ON-AQP4 had visual function more severely compromised than the other ON-groups, yet strutural OCT retinal measures were similar between the affected groups. Hence, we still need to unravel the evidence of structural-functional dissociation in these cases.