In spite of these innovations bifocal contact lenses and their variations are obviously far from perfected. For those who can’t be fitted, or who fail to adjust to bifocal lenses, there are a few alternatives and compromises. A very popular one and one that is extensively employed is the “monovision technique.” One eye is fitted for distance (usually the dominant eye); the other is fitted for reading. Either hard or soft contact lenses may be used, and this is by far the best technique found to date: The success rate is estimated at between 70 and 80 percent. As in the past, when monocles were worn, the eyes and brain somehow manage to make sense out of what seems to be visual schizophrenia. Read the rest of this entry »
Eventually everyone experiences presbyopia. This is the normal aging process of the eye, which begins around the age of forty for most people, and is caused by the gradual loss of elasticity in the natural crystalline lens of the eye. The lens loses its ability to change shape the way it used to, and fails to bring the light rays of near objects into sharp focus. Of course a nearsighted person over the age of forty can see near objects clearly with the naked eye, but will have difficulty doing so if he is wearing glasses or contact lenses that correct his myopia. Read the rest of this entry »
Conventional soft contact lenses cannot be used to correct moderate to large amounts of astigmatism. Their pliable nature causes them to conform to irregularities in the shape of the cornea and thus duplicate the astigmatic refractive error. Hard contact lenses are firm and hold their shape; they are able to correct high amounts of astigmatism because the spherical undersurface of the lenses and the tears beneath them create a new, smooth optical surface. Read the rest of this entry »
Contact Lenses Care .
