Optical coherence tomography in multiple sclerosis: a systematic review and meta-analysis

Abstract

Optical coherence tomography (OCT) is a new method that could aid analysis of neurodegeneration in multiple sclerosis (MS) by capturing thinning of the retinal nerve fibre layer (RNFL). Meta-analyses of data for time domain OCT show RNFL thinning of 20.38 microm (95% CI 17.91-22.86, n=2063, p<0.0001) after optic neuritis in MS, and of 7.08 microm (5.52-8.65, n=3154, p<0.0001) in MS without optic neuritis. The estimated RNFL thinning in patients with MS is greater than the extent expected in normal ageing, probably because of retrograde trans-synaptic degeneration and progressive loss of retinal ganglion cells, in addition to the more pronounced thinning caused by optic neuritis if present. RNFL thickness correlates with visual and neurological functioning as well as with paraclinical data. Developments that could improve understanding of the relation between structure and function in MS pathophysiology include spectral or Fourier domain OCT technology, polarisation-sensitive OCT, fluorescence labelling, structural assessment of action-potential propagation, and segmentation algorithms allowing quantitative assessment of retinal layers.

Pattern of gray matter volumes related to retinal thickness and its association with cognitive function in relapsing–remitting MS

“…Unfortunately, the sample size was too small to investigate the impact of ON in depth. ON leads to a predominant loss of RNFL thickness in the anterior visual pathway, which translates only to a much lower extend of volume loss in related brain regions (Balcer et al., 2015; Petzold et al., 2010). However, accounting for previous ON in our models was sufficient to preserve the strong association with the insula in the whole cohort.…”

“…Retinal nerve fiber layer (RNFL) thickness has already been used as an OCT endpoint in a multicenter phase 2 trial and will probably be increasingly used due to the easy, fast, and noninvasive assessment (Sühs et al., 2012). Moreover, OCT measures seem to have moderate but consistent correlation with brain parenchymal fraction and brain volume (Balcer et al., 2015; Petzold et al., 2010). The correlation with gray and white matter volume is inconsistent and correlations are generally weak to moderate (Young et al., 2013).…”

Quantitative analysis of the intraretinal layers and optic nerve head using ultra-high resolution optical coherence tomography

“…1 Recent advances in ultra-high resolution spectral domain OCT make this imaging modality more useful in research and patient care. 2 OCT can provide high-resolution cross-sectional images of the retina to aid in identifying, monitoring, and quantitatively assessing ocular diseases 1,3,4 and ocular manifestations of diseases in the central nervous system disorders, such as multiple sclerosis 5,6 and stroke. Most of commercially available OCT devices have an approximately axial resolution of 5 μm and are limited to a few segmented intraretinal layers, although the segmentation is mostly automatic.…”

Optical Coherence Tomography in Patients with Relapsing-Remitting Multiple Sclerosis without Optic Neuritis: A 20-Month Longitudinal Study

“…However, in the recent few years, several studies demonstrated the presence of axonal degeneration even in the initial stages of MS. [1][2][3][4] Axonal loss is an irreversible process and is related to permanent disability observed in MS; therefore, the monitoring of axonal loss is important for the follow-up of the disease and the development of a targeted treatment strategy. 2 Retinal cell axons are part of the CNS, and do not have a myelin sheath until they penetrate the lamina cribrosa, thus the investigation of retina might be ideal for visualising the processes of neuroaxonal degeneration and understanding mechanisms of brain tissue damage in multiple sclerosis. 5 One of the relatively novel techniques for investigation of retina is optical coherence tomography (OCT).…”