advertisement
Abstract #15412 Published in IGR 1-3
Acquired colour vision defects in glaucoma-their detection and clinicalsignificance.
Pacheco-Cutillas M; Sahraie A; Edgar DFBritish Journal of Ophthalmology 1999; 83: 1396-1402
The authors present a review on the relevant literature, they distinguish between congenital and acquired defects, they describe methods of examination and finally assess the effects of acquired color defects on the quality of life in patients with primary open angle glaucoma. Among the color tests that they discuss is also short-wave length automated perimetry. As far as quality of life measurements is concerned, color vision is one subscale in the National Eye Institute visual function questionnaire. It seems that to date there is insufficient evidence to be certain of the significance of acquired color vision deficiency in quality of life. Summary: By the time the earliest visual field defects in POAG can be detected using typical increment threshold perimetry, extensive and irreversible neuronal damage has occurred. Investigation of colour mechanisms may allow detection of POAG at an earlier stage than conventional perimetry, resulting in improved prognosis. Standard clinical colour vision tests involving anomaloscopes, pseudo-isochromatic plates, and arrangement tests, although distinguishing patients with well developed glaucoma from normals, do not appear to have high enough sensitivity and specificity to act as screening techniques at earlier stages of the disease. Compared with these clinical tests, the new computerised techniques are potentially more valuable in detecting POAG because they can assess colour vision at specified retinal locations. However, data published to date suggest that investigation of chromatic signals on its own may not be sufficient to detect or predict the progress of the disease. This is partially due to the fact that the precise neurobiology of the disease is not yet fully understood and POAG may differentially affect various neuronal layers of the retina. It is, therefore, possible that a battery of tests which include investigation of chromatic signals together with transient motion signals, flicker / luminance sensitivity, and SWAP may yield more accurate indices for predicting / monitoring the various stages of the disease.
AVRC, Department of Optometry and Visual Science, City University, NorthamptonSquare, London EC1V 0HB.
Classification:
6.6.3 Special methods (e.g. color, contrast, SWAP etc.) (Part of: 6 Clinical examination methods > 6.6 Visual field examination and other visual function tests)
