Word: optic
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...under a local anesthetic. Doctors scan the woman with pulsed sound waves to locate the fetus, the umbilical cord and the placenta. After making a small incision in the abdomen, they insert into the uterus and the amniotic sac a pencil-lead-thin tube containing an endoscope with fiber-optic bundles that transmit light. This enables the physicians to see tiny areas of the fetus. By inserting biopsy forceps into the tube, doctors can take a 1-mm (.04 in.) skin sample from the fetus. They prefer to excise it from the head, where there are no major blood vessels...
...myopia, nor how much heredity or eye-strain is to blame. "Myopia has been associated with everthing from pregnancy to tooth decay," Greene says. Researchers agree only that myopia is the abnormal bulging of the back of the eye or "posterior sclera," usually around the gap for the optic nerve. But no one is sure what causes the swelling, whether myopics are born with bulge or have brought it on themselves by reading in dark corners...
...reading. The tension stretches and strains the sclera. Though such stretching is normally elastic, if it is both frequent and extreme enough the sclera does not return to its normal position and myopia develops. Second, the eye is least able to reduce strain near the point where the optic nerve enters the eye--Greene draws an analogy with the rivet holes in airplane wings, the weakest point of an airplane's body. This factor may explain why myopia is concentrated about the optic nerve...
...biomechanical model shows that myopia is both acquired and inherited. Excessive stress may explain how it is acquired, while location of the oblique muscles explains how it may be inherited. If someone is born with their oblique muscles attached near the optic nerve, they are more prone to myopia than most individuals...
...benign skin tumors that can grow to look like brown cauliflower-may form anywhere on the body, particularly on the back, chest and abdomen. In severe cases, the body is eventually covered by thousands of these tumors. Some may develop internally, attaching to the brain's acoustic or optic nerves and other vital tissues. Another, rarer manifestation of the disease is "elephant skin," large hanging folds of epidermis...