Analysis Of Factors Related To The Thickness Of Retinal Nerve Fiber Layer In Patients With Neuromyelitis Optic Spectrum Disorders

Objectives: analyze the influence of relevant clinical indicators of NMOSD patients,such as recurrence times,AQP4 antibody,EDSS score,etc.,on RNFL thickness,and explore and analyze the mechanism.compare the differences of retinal nerve fiber layer(RNFL)thickness in different neuromyelitis optic spectrum disorders(NMOSD)subgroups,so as to provide a more reliable basis for future OCT evaluation of NMOSD patients.Methods: a retrospective study was conducted on 41 patients who met the revised NMOSD diagnostic criteria and inclusion criteria of Wingerchuk in 2015 and were reviewed in the neurology department of our hospital from January 2019 to January 2020.According to previous history of optic neuritis(ON),there were 19 cases in the ON(+)group and 22 cases in the ON(-)group,and 29 cases in the AQP4(+)group and 12 cases in the AQP4(-)group according to the AQP4 antibody.The demographic and clinical characteristics of each group were described,and statistically analyzed whether there were significant differences in RNFL thickness and visual acuity between each group.Statistical analysis was applied to factors that might contribute to RNFL thickness thinning.Results: The age at first onset(P=0.013),duration of the disease(P =0.002),total number of recurrence(P<0.001),EDSS score(P=0.028),are statistically different between the ON subgroups.Furthermore,separate patients' eyes by the history of ON,there are statistical differences in visual acuity,mean RNFL thickness in each quadrant(temporal quadrant,nasal quadrant,superior temporal quadrant,inferior temporal quadrant,superior nasal quadrant,inferior nasal quadrant)of RNFL thickness(P <0.001)between 33 ON eyes and 49 none ON eyes.There are no significant differences in age of first onset(P=0.422),mean RNFL thickness(P=0.630),duration of disease(P=0.528),number of ON(P=0.975)and total number of recurrences(P=0.589),EDSS score(P=0.196),visual acuity(P =0.477)between the AQP4(+)group and the AQP4(-)group.There is no statistical difference between the RNFL thickness of each quadrant after partition according to different quadrants(P>0.05).When exploring the related factors that influence the RNFL thickness,age at first onset(P=0.764)can not significantly affect the RNFL thickness,while ON recurrence rate(P= 0.000),disease duration(P= 0.033),EDSS score(P=0.003)can significantly affect the RNFL thickness,namely the more recurrences of ON,the longer the duration,the higher the EDSS score,the thinner the RNFL thickness.Gender(P=0.848)had no significant effects on RNFL thickness.Conclusion: compared with ON(-)group,RNFL in ON(+)group was significantly reduced RNFL thickness.The number of ON recurrence,EDSS scores and duration of the disease could all affect the thickness measured in RNFL.For NMOSD patients with the medical history of ON recurrence,using OCT as an ophthalmologic examination should be performed regularly while focusing on the management in other parts of the body.At the same time,when using OCT to measure NMOSD patients' RNFL thickness for disease evaluation,the possible factors such as ON recurrence,the duration of the disease and EDSS scores should be taken into account.