Research:Hope Prof G remembered to look at Colour Vision in his new Trial

Villoslada P, Cuneo A, Gelfand J, Hauser SL, Green A.Color vision is strongly associated with retinal thinning in multiple sclerosis.Mult Scler. 2012 Jan [Epub ahead of print]

Objectives:
Multiple Sclerosis (MS) frequently causes injury to the anterior visual pathway (AVP), impairing quality of life due to visual dysfunction. Development of biomarkers in MS is a high priority and both low-contrast visual acuity (LCVA. Grey Coloured reading chart) and time-domain optical coherence tomography (TD-OCT. Optical coherence tomography (OCT) is like ultrasound of the eye that uses infra red light rather than sound to get the image) have been proposed as candidates for this purpose. We sought to assess whether psychophysical assessments of color vision are similarly correlated with structural measures of AVP injury, and therefore augment measures of visual disability in MS.



Methods: We studied the association between high-contrast visual acuity (HCVA. Black colour charts), LCVA, color vision (Hardy-Rand-Rittler plates (HRR Colourblind charts) and Lanthony D15 tests colour arrangement test) and OCT, using both high-resolution spectral-domain OCT (SD-OCT. New generation machine) and TD-OCT (Older type machine) in a group of 213 MS patients (52 with previous optic neuritis) and 47 matched controls in a cross-sectional study.
Lanthony Test


Results: We found that MS patients have impairments in HCVA and LCVA (p less than 0.001) but that they suffer from even more profound abnormalities in color discrimination (p less than 0.0001). We found strong correlation between color vision and SD-OCT measures of retinal nerve fiber layer (RNFL) thickness (average RNFL, r = 0.594 (p less than; 0.001) and papillomacular bundle thickness (r = -0.565, p less than 0.001). The correlation between OCT scores and functional visual impairments of all types was much stronger for SD-OCT than for TD-OCT.


Conclusion: Our results indicate that color vision is highly correlated with these OCT scores when compared with traditional measures of visual acuity. Also we found that SD-OCT is superior to TD-OCT for detecting anterior visual pathway damage in MS. This makes both colour-visual measures and SD-OCT strong candidate biomarkers of disease progression.
(Hardy-Rand-Rittler plates)


This study further indicates that nerve damage that occurs during Ms can be seen in the function of the eye. They say that there is a STRONG correlation between the degree of colour vision and the thickness of the retinal nerve fibre layer (RNFL as a measure of nerve content) which contains the nerve heads of the optic nerve, which are damaged during MS. They put an r value of r = 0.594 (this is not strong, r=1.0 (positive correlation as one outcome gets bigger the other outcome gets bigger or r= -1 is strong as one outcome gets bigger the other outcome gets smaller). Likewise as the macula (place where light is focussed in the eye and is the place where most accurate vision occurs) gets thicker, possibly due to swelling, colour vision gets reduced.


Based on some studies from Team G, Prof G has produced a novel trial design for the treatment of nerve damage, with the hope of finding drugs for progressive MSers. This is based around studying eye function. This study is a further example that this is not such a bad idea. Hope Prof G is testing colour descrimination. This trial has recently begun.

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