title: Using retinal architecture to help characterize multiple sclerosis patients.
abstract: OBJECTIVE
  We compared retinal nerve fibre layer (RNFL) thickness and visual function in a heterogeneous multiple sclerosis (MS) cohort to determine whether optical coherence tomography (OCT) may complement the existing methods used to characterize MS patients.
  
  
  METHODS
  Cross-sectional cohort study.
  
  
  METHODS
  One hundred and ninety-three patients with optic neuritis (ON) as a clinically isolated syndrome (CIS) (n = 63), relapsing-remitting MS (RRMS) (n = 108), secondary progressive MS (SPMS) (n = 13), and primary progressive MS (PPMS) (n = 9).
  
  
  METHODS
  All patients underwent standardized ophthalmic, neurological, and OCT testing at a single academic institution.
  
  
  RESULTS
  RNFL values were reduced in PPMS (94.3 µm), RRMS (99.6 µm), and SPMS eyes (84.7 µm) relative to CIS eyes (105.7 µm) (p<0.0001). RNFL values were lower in eyes with recurrent ON (64.2 µm) relative to eyes affected by a single ON event (86.3 µm) (p<0.0001). The strongest correlation between RNFL thickness and neurological disability occurred in RRMS patients (r = -0.51, p < 0.0001). RNFL thickness correlated with visual field sensitivity for CIS (r = 0.23, p < 0.01) and RRMS (r = 0.22, p < 0.01) patients. Simple linear regression showed that every 10 µm decrease in RNFL correlated with a 5.8 decibel decrease in visual field sensitivity (adjusted R2 = 0.35, p < 0.0001) for RNFL values less than 75 µm.
  
  
  CONCLUSIONS
  There were robust correlations between RNFL thickness and visual function, particularly in ON eyes. OCT may complement the existing tools used to characterize MS patients, but further studies are needed.
authors.affiliation: Departments of Clinical Neurosciences and Surgery, Hotchkiss Brain Institute, University of Calgary, Calgary, Alta. Fiona.Costello@albertahealthservices.ca
authors.forename: Fiona
authors.initials: F
authors.lastname: Costello
authors.forename: William
authors.initials: W
authors.lastname: Hodge
authors.forename: Y Irene
authors.initials: YI
authors.lastname: Pan
authors.forename: Eric
authors.initials: E
authors.lastname: Eggenberger
authors.forename: Mark S
authors.initials: MS
authors.lastname: Freedman
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D009103:Multiple Sclerosis / Q000175:diagnosis*; D009412:Nerve Fibers / Q000473:pathology*; D009902:Optic Neuritis / Q000175:diagnosis*; D012165:Retinal Ganglion Cells / Q000473:pathology*; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology; D014794:Visual Fields / Q000502:physiology