title: Evaluation of visual structural and functional factors that predict the development of multiple sclerosis in clinically isolated syndrome patients.
abstract: OBJECTIVE
  To evaluate visual pathway structure and function in patients with clinical isolated syndrome (CIS) by using spectral-domain optical coherence tomography (OCT) and multifocal visual-evoked potentials (mfVEP), predicting CIS conversion to clinically definite multiple sclerosis (MS).
  
  
  METHODS
  This observational, longitudinal study assessed the eyes with no previous history of optic neuritis of 29 consecutive patients with CIS according to the McDonald criteria. The relationships of the mfVEP results with the clinical findings, and psychophysical (Humphrey perimetry) and structural (OCT) diagnostic test data were investigated.
  
  
  RESULTS
  The mfVEP amplitude responses (interocular and monocular probability analysis) showed abnormal cluster visual field defects in 48.3% of the CIS eyes, whereas mfVEP latency analysis showed significant delays in 20.7%. The OCT average retinal nerve fiber layer thickness (RNFLT) was significantly reduced compared with the control group (P = 0.02). Significant differences between CIS eyes with abnormal and normal mfVEP latencies were found for the OCT RNFLT (P < 0.001) with a longer latency being linked to more severe axonal damage. Using multivariate logistic regression analysis, OCT average RNFLT was found to be an independent predictor of clinically definitive MS diagnosis at 12 months.
  
  
  CONCLUSIONS
  The combined use of OCT and mfVEP is helpful to detect significant subclinical visual pathway abnormalities and axonal loss in CIS patients. Retinal axonal loss measured by OCT is an important prognostic factor of conversion to MS in patients with CIS in absence of symptomatic optic neuritis.
authors.affiliation: Department of Ophthalmology, University Hospital Príncipe de Asturias and Department of Surgery, University of Alcalá, Madrid, Spain.
authors.forename: Consuelo
authors.initials: C
authors.lastname: Pérez-Rico
authors.affiliation: Department of Neurology, University Hospital Príncipe de Asturias, Alcalá de Henares, Madrid, Spain.
authors.forename: Lucia
authors.initials: L
authors.lastname: Ayuso-Peralta
authors.affiliation: Department of Neurology, University Hospital Príncipe de Asturias, Alcalá de Henares, Madrid, Spain.
authors.forename: Lluisa
authors.initials: L
authors.lastname: Rubio-Pérez
authors.affiliation: Department of Ophthalmology, University Hospital Príncipe de Asturias, Alcalá de Henares, Madrid, Spain.
authors.forename: Isabel
authors.initials: I
authors.lastname: Roldán-Díaz
authors.affiliation: Department of Medicine, University Hospital Principe de Asturias, Alcalá de Henares, Madrid, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Arévalo-Serrano
authors.affiliation: Department of Radiology, University Hospital Príncipe de Asturias, Alcalá de Henares, Madrid, Spain.
authors.forename: Dolores
authors.initials: D
authors.lastname: Jiménez-Jurado
authors.affiliation: Department of Surgery, University of Alcalá, Madrid, Spain.
authors.forename: Román
authors.initials: R
authors.lastname: Blanco
mesh_terms: D000328:Adult; D003711:Demyelinating Diseases / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009103:Multiple Sclerosis / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D012164:Retinal Diseases / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D012165:Retinal Ganglion Cells / Q000473:pathology*; D012607:Scotoma / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D041623:Tomography, Optical Coherence / Q000379:methods*; D014792:Visual Acuity; D058609:Visual Field Tests; D014795:Visual Pathways / Q000503:physiopathology
keywords: clinically isolated syndrome; multifocal visual-evoked potentials; spectral-domain optical coherence tomography; subclinical retinal axonal loss