Understanding the Eye and the Lens
The eye, arguably the most important sensory organ, has evolved to provide detailed imagery of the world around us in much the same way that a camera provides a photographer with a picture. Like a camera, the eye contains a series of internal structures instrumental to its function. Like a camera’s lens shutter, the cornea represents a protective layer of cells that help refract light. As with a camera’s lens, the main function of the optic lens is to refract light and help focus it on the retina, where images are processed into signals that can be interpreted by the brain via the optic nerve. The proper function of the lens hinges on its transparency (MedlinePlus 2012).
The lens can be thought of as a light-permeable barrier consisting of two major components: an epithelium and a mass of fiber cells. The epithelium, which is a single layer of cells nearest the front of the eye, provides protection to the interior layers. The inner mass of elongated fiber cells ensures the transparency of the lens (Bhat 2001). Maintenance of healthy structure and function of the lens depends on proper functioning of complex cellular machinery, which if compromised, can lead to decreased lens transparency (Mathias 2010; Michael 2011).