Evaluation of visual structural and functional factors that predict the development of multiple sclerosis in clinically isolated syndrome patients.
PURPOSE
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.
['Pérez-Rico|Consuelo|C|', 'Ayuso-Peralta|Lucia|L|', 'Rubio-Pérez|Lluisa|L|', 'Roldán-Díaz|Isabel|I|', 'Arévalo-Serrano|Juan|J|', 'Jiménez-Jurado|Dolores|D|', 'Blanco|Román|R|']
D000328:Adult D003711:Demyelinating Diseases D005074:Evoked Potentials, Visual D005260:Female D005500:Follow-Up Studies D006801:Humans D008297:Male D009103:Multiple Sclerosis D012164:Retinal Diseases D012165:Retinal Ganglion Cells D012607:Scotoma D041623:Tomography, Optical Coherence D014792:Visual Acuity D058609:Visual Field Tests D014795:Visual Pathways
clinically isolated syndrome spectral-domain optical coherence tomography multifocal visual-evoked potentials subclinical retinal axonal loss