Word: retinas
(lookup in dictionary)
(lookup stats)
Dates: during 1930-1939
Sort By: most recent first
(reverse)
...bright pink retina of the eye can be photographed straight through the pupil with a Zeiss retinal camera. As reference points for classification, veins are chosen in preference to arteries because they are thicker and show up darker in photographs. The main vein which enters the eyeball with the optic nerve branches in two, and each branch again forks, providing four prominent veins meandering across the retina in irregular directions.* The entrance point of the optic nerve itself is taken as a point of reference. The distances and directions of the vein forks from this reference point provide coordinates which...
...dreadful word among doctors is glaucoma, hardening of the eyeballs. Salt and water in the blood seep out of the blood vessels of the eye and into the eye's cavity. Because this salty liquid cannot escape, it jams the retina against the wall of the eye, slowly destroys the tasseled end of the optic nerve. Vision dims, blindness ensues. Drugs have proved of little help; surgery gives only temporary relief...
...cornea, or transparent front coating of the eyeball, occasionally becomes clouded, so that light cannot get through to the retina. Result: blindness. Eye surgeons recently perfected the operation of replacing such a clouded cornea with a corneal graft from the useless eye of an-other human being (TIME, Oct. 29). Last week Dr. Ramon Castroviejo of Manhattan performed that operation on the left eye of Fremont Clark of Wadena, Iowa with this new twist: Instead of waiting for another patient to give up his cornea, Dr. Castroviejo gave Mr. Clark the cornea of a still-born baby...
Aniseikonia is Greek for "unequal images." When the sufferer looks at any object, the image reflected in the retina of one eye differs in size and shape from that in the other. The struggle of the brain's visual centre to fuse these two images brings aches, pains and frazzled nerves. Sometimes it cannot fuse them...
...Dartmouth researchers are not yet sure of aniseikonia's cause. They think it may be some malformation of the front part of the eye, or a larger number of light-sensitive cones in one retina than in the other. To detect the condition they have devised a complex instrument of peepholes, dots and lights, called the Ophthalmo-Eikonometer. To correct the condition they, and American Optical Co., have developed "iseikonic spectacles" with miniature telescope lenses to balance images...