Until the advent of contact lenses or intraocular lens implants spectacles were the only means of achieving a finely focused image on the retina after a cataract operation. Although in many cases this is most satisfactory, there are limitations to such correction. At first some patients find that wearing thick cataract glasses causes a number of problems which arise from magnification of the image, distortion in the peripheral part of vision, and some limitation of the field of clear vision.
These all result from the spectacle lens itself rather than from the operation. Read the rest of this entry »
In an ideal world the best way to restore an eye to normal would be to replace the cataractous lens with a clear one of the same power lying in the position from which the original lens was removed.
At the Oxford Ophthalmological Congress the eye surgeon Harold Ridley reported the results of eight operations that he had performed to insert a Perspex lens. He thus founded a completely new branch of ophthalmic surgery. Ridley had treated many ocular injuries suffered by members of the Royal Air Force during World War II. Aircraft windshields (made of Perspex) had shattered after explosions or the impact of bullets, and Perspex fragments had penetrated the eyes of plane crews. Ridley had noticed how inert Perspex was in the eye and how little inflammation it caused. Read the rest of this entry »
For the first two weeks or so of the immediate postoperative period vigorous activity is discouraged. Stooping, lifting heavy objects, sneezing or coughing, and any very violent physical effort should be avoided. Any activity that makes the patient feel that his collar is too tight or that his neck is swelling should be stopped because movements which cause congestion in the head also provoke an increase in pressure within the eye. Until the wound is properly healed this could lead to its leaking, to haemorrhage, to poor healing, and, in the worst event, to loss of the eye. After two weeks, however, the surgical wound should be well healed. At the routine outpatient visit which should be made at this time, the state of healing will be assessed by the surgeon, who will tell the patient what physical activities may be undertaken. Read the rest of this entry »
The retinae are the sensory parts of the eyes, and to all intents and purposes may be regarded as a part of the brain. At the embryonic stage the developing brain very early on grows two buds which will become the eyes. This brain tissue gradually transforms into the light-sensitive retinae, or receptor organs. In the young foetus the buds lie just below the skin surface. The forward part of the eye tissue then invaginates to form the crystal lens of the eye, while the skin forms the cornea, or front lens of the eye. Slowly each bud is extended away from the brain, until it is only attached to the brain by a stalk, or optic nerve. Read the rest of this entry »
