Characteristics And Associated Factors Of Visual Impairment Caused By Neuromyelitis Optica Spectrum Disorders

Objective:To analyze the clinical and ophthalmological characteristics of visual impairment caused by neuromyelitis optica spectrum disorders(NMOSD).To explore associated factors for the development and severity of visual impairment and explain their significance aiming to provide reference for clinicians in the differential diagnosis,assessment and prognostic prediction of visual impairment caused by NMOSD.Methods:We retrospectively analyzed 76 patients from January 2013 to December 2018 in Renji hospital who met the 2015 international consensus diagnostic criteria for NMOSD and 25 patients who met the 2017 diagnostic criteria for multiple sclerosis(MS).The clinical and ophthalmological data of NMOSD and MS patients were collected and compared in search for potential markers to differentiate these two disease entities.Among the NMOSD group,patients were bisected into group with good performance and group with bad performance based on the results of ophthalmological examination and mono-factor analysis were adopted to screen for associated factors of visual impairment caused by NMOSD.The correlation between clinical,biochemical data and ophthalmological data were further explored by Spearman or Pearson correlation analysis.Results:A total of 76 NMOSD patients and 25 MS patients were enrolled.Between the two groups,there were no significant differences in ON history,ON as first symptom,ON ARR,visual acuity,MD,sLV,RNFL thickness of inferior quadrant,RNFL thickness of nasal quadrant,RNFL thickness of temporal quadrant,latency of P100,amplitude of P100(P>0.05)while there were statistically significant differences in female proportion,age of onset,disease duration,attack times of ON,proportion of bilateral involvement,EDSS score,proportion of visual acuity worse than 0.01 for at least one eye,Ms,RNFL symmetry,average RNFL thickness,RNFL thickness of superior quadrant,proportion of unelicited P100 for at least one eye(P<0.05).Among the NMOSD patients,there were statistically significant differences in visual acuity,ON history and ON as first symptom(P<0.05)between the group with good visual acuity and group with bad visual acuity.There were statistically significant differences in proportion of positive serum ANA,proportion of positive serum AQP4-Ab(P<0.05)between the group with good visual field and group with bad visual field while the logarithm of maximum serum ANA titer was positively correlated with MD(R=0.374,P=0.015).There were statistically significant differences in average RNFL thickness,female proportion,age of onset(P<0.05)between the group with good RNFL and group with bad RNFL.Moreover,there were statistically significant differences in latency of P100,EDSS score,proportion of positive serum ANA(P<0.05)between the group with good VEP and group with bad VEP while the logarithm of maximum serum ANA titer was positively correlated with latency of P100(R=0.363,P=0.008).Conclusion:Our study reveals that visual impairment caused by NMOSD is generally more severe than that of MS regardless of clinical manifestation or results of ophthalmological examination.Bilateral involvement,visual acuity worse than 0.01,unelicited P100,significant RNFL asymmetry,decreased RNFL thickness of all quadrants with the RNFL thickness of superior quadrant decreasing worst are more likely to appear in visual impairment caused by NMOSD.The presence of serum ANA is significantly correlated with visual impairment caused by NMOSD,the increase of serum ANA titer is correlated with more severe visual impairment.Therefore,it is recommended that for those NMOSD patients with positive serum ANA,ophthalmological examination should be fully carried out.Conversely,for those NMOSD patients with visual impairment,the presence of ANA should be excluded as well.