Optical coherence tomography angiography enhances the detection of optic nerve damage in multiple sclerosis

Background Quantitative assessment of optic nerve damage is important in the evaluation of optic neuritis (ON) and multiple sclerosis (MS). Objective To detect optic nerve damage using optical coherence tomography (OCT) and OCT angiography in MS. Methods Peripapillary retinal nerve fibre layer (NFL) thickness, macular ganglion cell complex (GCC) thickness and Optic Nerve Head Flow Index (ONH-FI) were measured. The ONH-FI was defined as flow signal averaged over the optic disc. Diagnostic accuracy was evaluated by the area under the receiver-operating characteristics curve (AROC). Results Sixty-eight eyes of 45MS participants and 55 eyes of 32 healthy controls (HCs) were analysed. Of MS eyes, 25 had a history of ON (MS+ON) and 43 didn't (MS-ON). MS-ON and MS+ON eyes had reductions in ONH-FI (p=0.031and p=0.001, respectively), GCC thickness (p=0.245and p<0.001, respectively), and NFL thickness (p=0.003and p=0.024, respectively), compared with HCs. The highest AROC (0.940) was achieved by the logistic regression combination of all three variables, which was significantly higher than other variables (p=0.018). Conclusion MS produces both retinal structural loss and decreased ONH perfusion in MS eyes with and without history of ON. The combination of perfusion and structural measurements enhances detection of optic nerve damage in MS. OCT angiography may be a useful additional retinal marker in evaluation of ON in MS.