Instrumentation: The Machines of Progress

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The man on the opposite page is not made up for a Hollywood horror movie.

He is undergoing a sensitive and still experimental examination designed to detect changes in blood flow and temperature that may be produced by vas cular disorders. Capable of indicating temperature variations as small as .047° F, the liquid crystals he has been painted with were originally developed for testing mechanical stresses in deli cate instruments. But their quickly identifiable color changes may prove far more valuable for humans.

Such new diagnostic techniques are typical of a whole sunburst of medical marvels that cover a spectrum as wide as the liquid crystals' own color range. In addition to teaching doctors to see with colors, engineers have also shown them how to see with sound. Ultrasonic beams bounced through a patient can spell out a fuzzy picture of all they encounter. Operations can now be carried out in an environment that is virtually germfree. The new device may be as comparatively simple as a heart cart that contains everything from a cardiac pacemaker to a supply of oxygen, and can, in effect, rush the entire equipment of a hospital emergency room directly to a heart patient's bedside. Or it may be as vastly complex as the proton gun currently being used by Harvard Neurosurgeons Raymond Kjellberg and William Sweet.

Sound & Fury. Using 700-ton magnets, Harvard's cyclotron fires a proton beam with the force of 160 million electron volts. But after leaving the cyclotron, the protons travel a precise and predictable distance before they release their power. Careful positioning of the patient allows the beam to pierce the skin with little damage before releasing all its energy and destroying a specific target deep inside the body—such as the pituitary gland, perhaps, or a brain tumor.

In one way or another, much of the new medical machinery is beneficial fallout from the miniaturization and precise measurement techniques learned by space-age scientists. Like protons, the furious but controllable forces of laser beams have already been used as exact surgical scalpels; at the National Institutes of Health, laser light is also being showered on cultures grown for only four hours in tiny, 2-mm. capillary tubes. The resulting scattered light can be read for presence of bacteria. Because the process is so highly accurate, the cultures do not have to be nourished for days until they grow large enough for the disease-causing microbes to be detectable. The careful placing and size of an electrical charge is the key to Peri-Start, a machine built on the principle of the cardiac pacemaker. It electronically stimulates the muscles of bladder and colon and controls elimination in a paralyzed patient. In the future, the same technique may well prove practical for other muscles.