Retinal nerve fiber layer thickness in subgroups of multiple sclerosis, measured by optical coherence tomography and scanning laser polarimetry

Abstract

Optical coherence tomography (OCT) and scanning laser polarimetry (GDx ECC) are non-invasive methods used to assess retinal nerve fiber layer (RNFL) thickness, which may be a reliable tool used to monitor axonal loss in multiple sclerosis (MS). The objectives of this study are (1) to compare OCT with the GDx ECC; (2) to assess and compare the RNFL thickness in subgroups of MS. Ophthalmologic examination and RNFL assessment by OCT and GDx were performed in 65 MS patients (26 relapsing-remitting (RRMS), ten secondary-progressive (SPMS), 29 primary-progressive (PPMS)). Twenty-eight patients (43%) had a history of optic neuritis (ON). Adjustments were made for age and disease duration. RNFL thickness was reduced in eyes with previous ON (p < 0.01). No differences were found between PPMS and relapse-onset MS. OCT and GDx ECC measurements were moderately correlated (rho = 0.73, p < 0.01). Visual field-mean deviation (MD) values correlated with OCT means (r = 0.44, p < 0.01) and GDx ECC TSNIT average (r = 0.41, p < 0.01). In patients without previous ON, EDSS correlated with MD (r = −0.36, p < 0.01), visual field-pattern standard deviation (PSD) (r = 0.30, p < 0.05), OCT means (r = −0.31–0.30, p < 0.05) and macular volume (r = −0.37, p < 0.01). For MSIS-29 physical impact score, significant correlations were found with MD (r = −0.48, p < 0.01) and PSD (r = 0.48, p < 0.01). Conclusions: No differences between PPMS and relapse-onset MS subgroups were found. RNFL thickness was reduced in eyes with previous ON. Although OCT and GDx ECC findings were moderately correlated and showed significant correlations with measures of visual function in patients without previous ON, EDSS correlated significantly with visual and OCT measures, but not with GDx ECC.

Evaluation of Choroidal Vascular Changes in Patients with Multiple Sclerosis Using Enhanced Depth Imaging Optical Coherence Tomography

“…Several studies have observed a relationship between OCT measurements and EDSS score or disease duration [16,18,23,24,25]. Our results indicated no correlation between choroidal thickness and EDSS score, however a significant inverse correlation was detected between choroidal thickness and disease duration.…”

“…We also confirmed the results of previous studies that indicate a tendency of RNFL atrophy to be greater in ON-affected eyes than in unaffected eyes [20,21,22]. Previous studies reported that RNFL thickness was correlated with functional and structural measures of MS such as visual acuity, visual field, low-contrast letter acuity, contrast sensitivity, color vision, visual evoked potentials, brain atrophy assessed by magnetic resonance imaging and even quality of life [16,23,24,25,26]. In our study no correlation was found between RNFL and choroidal thickness measurements in both MS ON and MS non-ON eyes.…”

Relationship between Structural and Functional Assessment of the Visual System in Mildly Disabled Relapsing-Remitting Multiple Sclerosis Patients

“…36 Significant correlations between averaged RNFL thickness and VF loss have also been confirmed by other researchers. 28,37 On the other hand, a study by Noval et al demonstrated significant correlation between RNFL thickness and visual field loss at 1.5 and 3 months after ON, but not after 6 months. 38 The differing results of the above studies may be based on different study designs, MS subtypes, disability scores, and durations of the disease.…”

Comparison of Visual Field Parameters in Early and Advanced Stages of Multiple Sclerosis Patients Without a History of Optic Neuritis

“…18 Siepman et al reported that EDSS scores correlated with md, visual field-pattern standard deviation, RNFL thickness, and macular volume in MS patients without previous ON. 19 In another study, RNFL thickness and perimetric scores were significantly lower in MS group without a history of ON and …”