Abstracts of the 21st Annual Congress of the Ophthalmological Society of the West Indies, July 7-10, 2010, Antigua, West Indies.

摘要

The eye, the organ of sight, is well represented neurologi-cally. Of the three million afferent nerve fibers that enter the primate brain, two-thirds originate from the eyes and of the twelve cranial nerves over half are necessary for the optimal performance of the eye as a visual organ. Until recently, it has been considered that all incident light that enters the eye penetrates the inner layers of the retina to reach the photoreceptors. This initiates phototransduc-tion which is relayed to the occipital cortex by a three-neuron arc leading to the interpretation of the visual signal. More recently, a subpopulation of ganglion cells have been identified which respond directly to light utilizing the pigment melanopsin. These ganglion cells project to two main regions. Some connect to the tectal area and are responsible, in part, for the pupillary reflex. The majority form the retinohypothalmic pathway to the suprachiasmatic nucleus which represents the master circadian pacemaker. This centre controls diurnal fluctuations in bodily functions including intraocular pressures. Disturbances in circadian rhythm are associated with increased prevalence of disease states. Correction of dysynchronous circadian function could lead to novel therapeutic modalities.