: A tiny sensor has been developed to monitor fluid pressure in the brains of patients who have experienced brain trauma, such as from a coronary or a blow to the head. Unlike previous devices, however, this one does not need to be removed surgically. Instead, it is made of silicon and other materials that disintegrate over time and are eventually absorbed by the body. When implanted in the brain of a trauma victim, it indicates an increase in fluid pressure by bending, which changes its electrical resistance. A prototype has been successfully tested in rats; clinical trials in humans could start in three to five years.