Chromatic discrimination losses in multiple sclerosis patients with and without optic neuritis using the Cambridge Colour Test

Abstract

We assessed chromatic discrimination in multiple sclerosis (MS) patients both with (ON) and without (no ON) a history of optic neuritis using the Cambridge color test (CCT). Our goal was to determine the magnitude and chromatic axes of any color vision losses in both patient groups, and to evaluate age-related changes in chromatic discrimination in both patient groups compared to normals. Using the CCT, we measured chromatic discrimination along the protan, deutan and tritan axes in 35 patients with MS (17 ON eyes) and 74 age matched controls. Color thresholds for both patient groups were significantly higher than controls' along the protan and tritan axes (p < 0.001). In addition, the ON and no-ON groups differed significantly along all three-color axes (p < 0.001). MS patients presented a progressive color discrimination impairment with age (along the deutan and tritan axes) that was almost two times faster than controls, even in the absence of ON. These findings suggest that demyelinating diseases reduce sensitivity to color vision in both red-green and blue-yellow axes, implying impairment in both parvocellular and koniocellular visual pathways. The CCT is a useful tool to help characterize vision losses in MS, and the relationship between these losses and degree of optic nerve involvement.

Visual acuity evaluation in children with hydrocephalus: An electrophysiological study with sweep visual evoked potential

“…Several studies in our laboratory show changes in visual functions in many neurological patients with normal ophthalmologic diagnosis [20][21][22].…”

Métodos utilizados na avaliação psicofísica da visão de cores humana

“…Usando o CCT, Ventura e colaboradores (2003c) (Delahunt et al, 2004), parkinsonianos (Regan et al, 1998), sujeitos expostos ao consumo de álcool (Castro et al, 2009), usuários de cloroquina (Ventura et al, 2003c), neuropatia óptica hereditária de Leber ( Ventura et al, 2005( Ventura et al, , 2007a, pacientes com esclerose múltipla (Moura et al, 2008), com a distrofia muscular de Duchenne , intoxicados por mercúrio (Canto-Pereira et al, 2005;Feitosa-Santana et al, 2008;Rodrigues et al, 2007;Ventura et al, 2005). Também tem sido utilizado em pesquisas em ciência básica, como a avaliação da ausência de somação binocular, olho dominante e efeito da aprendizagem na discriminação de cores (Costa et al, 2006), aparência de cores para dicromatas (Brettel, Viénot, & Mollon, 1997), variações na mistura e discriminação de cores entre tricromatas e deuteranômalos, além de inspirar a criação de sistemas que usam o mesmo tipo de disposição do estímulo em mosaico para o estudo da discriminação do sistema visual humano (Figura 2) (Knoblauch, Vital-Durand, & Barbur, 2001;Rodrigues et al, 2007).…”

The Visual (dis)Function in Neurological Diseases

“…Our study show statistically significant losses in chromatic discrimination in MS patients as assessed by the CCT [134]. The impairment is present in MS even with no history of optic neuritis [131], although the ON group had more impairment.…”