Correlation of MRI lesions with visual psychophysical deficit in secondary progressive multiple sclerosis

Abstract

The aim of this work was, first, to clarify the nature of the relationship between the sensory deficit in the demyelinated visual pathway and morphological changes revealed by MRI and, secondly, to test whether there was a preferential effect of demyelination for either the magnocellular or parvocellular pathway in established multiple sclerosis. Twenty-four patients with secondary progressive multiple sclerosis were studied psychophysically and by MRI of the optic nerve and brain. MRI was performed with a Phillips (0.5T) scanner. Visual pathway MRI lesion load was evaluated independently using the total optic nerve lesion length and lesion area seen on STIR (short inversion time inversion recovery) images of the optic nerve and the total post-chiasmal lesion area on T(1)-, T(2)- and proton-density-weighted images of the brain. Psychophysical tests determined 75%-seeing thresholds for horizontal gratings consisting of isoluminant red and green sinusoids of the same spatial frequency combined out-of-phase for preferential stimulation of the parvocellular system and in-phase for preferential stimulation of the magnocellular system. It was found that, in this group of patients, visual psychophysical loss was significantly correlated with lesion area seen on proton density MRI sequences of the post-chiasmal visual pathway, and that the parvocellular pathway was more affected than the magnocellular pathway, especially at lower spatial frequencies.

A differential color flicker test for detecting acquired color vision impairment in multiple sclerosis and diabetic retinopathy

“…The color CFF procedure detected more pronounced color vision impairment in patients with optic neuritis than in patients with diabetic retinopathy. These findings agree with previous studies that used objective or subjective tests and reported altered chromatic sense in these patients [16][17][18][19][20][21][22][23][24][25][26][27][28][29]. As expected, we found a preferential impairment for red stimuli in patients with optic neuritis and for blue stimuli in patients with diabetic retinopathy.…”

“…Among current techniques for assessing visual system integrity in patients with optic neuritis or degenerative retinopathy [16][17][18][19][20][21][22][23][24][25][26][27][28][29]36] electrophysiological (i.e. color evoked potentials) and psychophysical (i.e.…”

The Visual (dis)Function in Neurological Diseases

“…Peripheral constriction in visual fields is a common find in MS patients, frequently related to a cortical atrophy or retrochiasmal damage in visual pathway [116,[119][120][121][122]. Additionally, spatial and temporal resolutions are also affected since the demyelination insult impairs the brainstem and also subcortical areas [123][124][125][126][127] evidenced by imaging studies [128].…”

Independent patterns of damage to retinocortical pathways in multiple sclerosis without a previous episode of optic neuritis

“…Earlier studies addressing visual function in ON have emphasized colour vision deficits [2][3][4][5] and suggested that the parvocellular stream, as compared to the magnocellular stream, is preferentially impaired in ON. However, these studies [2][3][4] focused on foveal vision, equated the magnocellular pathway with a pure luminance stream, and used a relatively low number of patients, with heterogeneous clinical status (some chronic, some subacute).…”

“…However, these studies [2][3][4] focused on foveal vision, equated the magnocellular pathway with a pure luminance stream, and used a relatively low number of patients, with heterogeneous clinical status (some chronic, some subacute). In an additional study [5], the relative isolation of parvocellular versus magnocellular (luminance) pathways was not optimized, given that temporal and spatial frequencies were neither explicitly manipulated nor optimized for functional separation.…”