Hostname: page-component-76fb5796d-x4r87 Total loading time: 0 Render date: 2024-04-30T06:06:48.840Z Has data issue: false hasContentIssue false

Reliability of Visual Temporal Thresholds

Published online by Cambridge University Press:  02 December 2014

L N Brown
Affiliation:
Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
M Eliasziw
Affiliation:
Department of Community Health Sciences, University of Calgary, Calgary, AB, Canada
L M Metz
Affiliation:
Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.
Background:

Visual processing deficits involving temporal characteristics are typically not captured by the widely used outcome measures (i.e., Expanded Disability Status Scale, Multiple Sclerosis Functional Composite) in multiple sclerosis (MS). Visual temporal thresholds (i.e., measurements of the temporal aspects in visual processing) are typically significantly higher (i.e., prolonged) in MS patients when compared to controls. The test-retest reliability of these thresholds was examined in patients with MS.

Methods:

Visual temporal thresholds were measured in 21 stable MS patients during two separate test sessions. Test-retest reliability and the standard error of measurement were calculated. The threshold of change in visual temporal thresholds in MS patients that would correspond to real change beyond measurement error with 95% certainty was also calculated. For comparisons, a control group (n = 10) was included.

Results:

The test-retest reliability of this measure of visual temporal thresholds was 0.97. The threshold indicating change beyond chance or measurement error with 95% certainty was 11 ms. Higher thresholds were significantly correlated with longer durations of disease.

Conclusions:

This measure of visual temporal thresholds has excellent test-retest reliability and a change of greater than 11 ms is highly likely to represent real change in MS patients. The findings indicate that these measurements may provide useful clinical information about functional changes regarding the temporal aspects of the visual system, which is currently not captured by the Extended Disability Status Scale.

Résumé:

RÉSUMÉ:<span class='italic'><span class='bold'>Contexte</span></span>:

Les déficits du traitement de l’information visuelle ayant des caractéristiques temporalis ne sont généralement pas détectés par les mesures communément utilisées (Expanded Disability Status Scale, Multiple Sclerosis Functional Composite) chez les patients atteints de sclérose en plaques (SEP). Les seuils visuels temporaux (c’est-à-dire les mesures des aspects temporaux du traitement de l’information visuelle) sont significativement plus élevés (c’est-à-dire prolongés) chez les patients atteints de SEP par rapport à des témoins. Nous avons évalué la fiabilité du test-retest de ces seuils chez des patients atteints de SEP.

<span class='italic'><span class='bold'>Méthodes</span></span>:

Les seuils visuels temporaux ont été mesurés au cours de deux sessions chez 21 patients atteints de SEP qui étaient stables. La fiabilité test-retest et l’erreur standard de la mesure ont été calculées. Le seuil de changement des seuils visuels temporaux chez les patients atteints de SEP qui correspondrait à un changement réel au-delà de l’erreur de la mesure avec une certitude de 95% a été calculé. À titre de comparaison, un groupe témoin (n = 10) a été inclus.

<span class='italic'><span class='bold'>Résultats</span></span>:

La fiabilité test-retest de cette mesure des seuils visuels temporaux était de 0,97. Le seuil indiquant un changement au-delà du hasard ou d’une erreur de mesure avec une certitude de 95% était de 11 ms. Des seuils plus élevés étaient corrélés significativement à une durée plus longue de la maladie.

<span class='italic'><span class='bold'>Conclusions</span></span>:

Cette mesure des seuils visuels temporaux a une excellente fiabilité test-retest et il existe une forte probabilité qu’un changement de plus de 11 ms représente un changement réel chez les patients atteints de SEP. Selon nos observations, ces mesures peuvent fournir une information utile en clinique sur les changements fonctionnels des aspects temporaux du système visuel, ce qui n’est pas détecté actuellement par le Extended Disability Status Scale.

Type
Original Articles
Copyright
Copyright © The Canadian Journal of Neurological 2007

References

1. McDonald, WI, Barnes, D. The ocular manifestations of multiple sclerosis: abnormalities of the afferent visual system. J Neurol Neurosurg Psychiatry. 1992;55:74752.Google Scholar
2. Newman, NJ. Multiple sclerosis and related demyelinating diseases. In: Miller, NB, Newman, NJ, editors. Walsh and Hoyt’s clinical neuro-ophthalmology, 5th ed. V5, p. 5539676. Baltimore: Williams & Wilkins; 1998.Google Scholar
3. Balcer, LJ, Baier, ML, Cohen, JA, Kooijmans, MF, Sandrock, AW, Nano-Schiavi, ML, et al. Contrast letter acuity as a visual component for the Multiple Sclerosis Functional Composite. Neurol. 2003;61:136773.Google Scholar
4. Baier, ML. Low-contrast letter acuity testing captures visual dysfunction in patients with multiple sclerosis. Neurol. 2005;64:9925.Google Scholar
5. Daley, ML, Swank, RL, Ellison, CM. Flicker fusion thresholds in multiple sclerosis: a functional measure of neurological damage. Arch Neurol. 1979;36:2925.Google Scholar
6. Mason, RJ, Snelgar, RS, Foster, DH, Heron, JR, Jones, RE. Abnormalities of chromatic and luminance critical flicker frequency in multiple sclerosis. Invest Ophthalmol Vis Sci. 1982;23:24652.Google Scholar
7. Titcombe, AF, Willison, RG. Flicker fusion in multiple sclerosis. J Neurol Neurosurg Psychiatry. 1961;24:2606.Google Scholar
8. Galvin, RJ, Heron, JR, Regan, D. Subclinical optic neuropathy in multiple sclerosis. Arch Neurol. 1977;34:66670.Google Scholar
9. Patterson, VH, Foster, DH, Heron, JR, Mason, RJ. Multiple sclerosis: luminance threshold and measurements of temporal characteristics of vision. Arch Neurol. 1981;38:6879.CrossRefGoogle ScholarPubMed
10. Vleugels, L, Charlier, A, van Nunen, A, Lafosse, C, Vogels, R, Ketelaer, P, et al. Temporal resolution deficits in the visual fields of MS patients. Vis Res. 1999;39:242938.Google Scholar
11. Vleugels, L, van Nunen, A, Lafosse, C, Ketelaer, P, Vandenbussche, E. Temporal and spatial resolution in foveal vision of multiple sclerosis patients. Vis Res. 1998;38:298797.Google Scholar
12. Brown, LN, Metz, LM, Sainsbury, RS. Sensory temporal thresholds and interhemispheric transfer times in multiple sclerosis: a preliminary study of a new outcome measure. J Clin Exp Neuropsych. 2003;25(6):78392.Google Scholar
13. Flanagan, P, Markulev, C. Spatio-temporal selectivity of loss of colour and luminance contrast sensitivity with multiple sclerosis and optic neuritis. Ophthamol Physiol Opt. 2004;25:5765.Google Scholar
14. Balcer, LJ. Optic Neuritis. N Engl J Med. 2006; 354:127380.CrossRefGoogle ScholarPubMed
15. Caruana, PA, Davies, MB, Weatherby, SJM, Williams, R, Haq, N, Foster, DH, et al. Correlation of MRI lesions with visual psychophysical deficit in secondary progressive multiple sclerosis. Brain. 2000;123:147180.Google Scholar
16. Brown, LN, Metz, LM. Tactile temporal thresholds detect relapse-related changes in multiple sclerosis: a preliminary study. Mult Scler. 2005;11:7257.Google Scholar
17. Brown, LN, Metz, LM, Eliasziw, M. Identifying reliable change in tactile temporal thresholds in multiple sclerosis: test-retest reliability. Mult Scler. 2006;12:5737.CrossRefGoogle ScholarPubMed
18. McDonald, WI, Compston, A, Edan, G, McDonald, WI, Compston, A, Edan, G, et al. Recommended diagnostic criteria for multiple sclerosis: guidelines from the International Panel on the Diagnosis of Multiple Sclerosis. Ann Neurol. 2001;50(1):1217.Google Scholar
19. Findlay, JM. Estimates on probability functions: a more virulent PEST. Percept Psychophys. 1978;23:1815.Google Scholar
20. Pentland, A. Maximum likelihood estimation: the best PEST. Percept Psychophys. 1980;28:30412.Google Scholar
21. Bland, JM, Altman, DG. Measurement error. BMJ. 1996;313:744.Google Scholar
22. Eliasziw, M, Young, SL, Woodbury, MG, Fryday-Field, K. Statistical methodology for the concurrent assessment of interrater and intrarater reliability: using goniometric measurements as an example. Phys Ther. 1994;74:77788.Google Scholar
23. Sergott, RC. Optical coherence tomography: measuring in-vivo axonal survival and neuroprotection in multiple sclerosis and optic neuritis. Curr Opin Ophthamol. 2005;16:34650.CrossRefGoogle ScholarPubMed
24. Fisher, JB, Jacobs, DA, Markowitz, CE, Galetta, SL, Volpe, NJ, Nano-Schiavi, ML, et al. Relation of visual function to retinal nerve fiber layer thickness in multiple sclerosis. Ophthalmol. 2006;113(2):32432.CrossRefGoogle ScholarPubMed
25. Parisi, V, Manni, G, Spadara, M, Colacino, G, Restuccia, R, Marchi, S, et al. Correlation between morphological and functional retinal impairment in multiple sclerosis patients. Invest Ophthalmol Vis Sci. 1999;40(11):25207.Google Scholar