when accidents that involve traumatic（外伤的） brain injuries occur, a speedy 1 followed by the proper treatment can mean the difference between life and death. a research team, led by jason d. riley in the section on 2 and 3 biophotonics at the u.s. national institutes of health, has created a handheld device capable of quickly detecting brain injuries such as hematomas（血肿） , which occur when blood 4 become damaged and blood 5（漏） out into surrounding tissues where it can cause significant and dangerous 6. a paper describing the team's proof-of-concept prototype for the hematoma detection device appears in the optical society's (osa) open-access journal biomedical optics express. the device is based on the concept of using instrumental motion as a signal in near-infrared imaging, according to the researchers, rather than treating it as noise. it relies on a simplified single-source 7 with a 8 separation 9 array and uses motion as a signal for detecting changes in blood volume in the tough, 10（最外面的） 11 12 the brain and 13 cord.
one of the primary applications for the finished device will be the rapid screening of traumatic brain injury patients before using more expensive and busy ct and mri imaging techniques. in cases where ct and mri imaging facilities aren't available, such as battlefields or on the scene of accidents, the team believes near-infrared imaging will help to determine the urgency of patient transport and treatment, as well as provide a means of monitoring known hematomas at the bedside or outpatient clinic（门诊诊所） .
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