A NEW APPLICATION FOR NEAR-INFRARED SPECTROSCOPY - DETECTION OF DELAYED INTRACRANIAL HEMATOMAS AFTER HEAD-INJURY

Clinical studies have documented the importance of secondary brain ins ults in determining neurologic outcome after head injury, Delayed intr acranial hematomas are one of the most easily remediable causes of sec ondary injury if identified early, but can cause significant disabilit y or death if not promptly recognized and treated, Early identificatio n and treatment of these lesions that appear or enlarge after the init ial CT scan may improve neurological outcome. Serial examinations usin g near-infrared spectroscopy (NIRS) to detect the development of delay ed hematomas were obtained in 167 patients. The difference in absorban ce of light (Delta OD) at 760 nm between the normal and the hematoma s ide was measured serially during the first 3 days after injury, Twenty -seven (16%) of the patients developed some type of late hematoma: an intracerebral hematoma in 8 patients, an extracerebral hematoma in 6 p atients, and a postoperative hematoma in 13 patients, Eighteen of the delayed hematomas caused significant mass effect and required surgical evacuation, The hematomas appeared between 2 and 72 h after admission . In 24 of the 27 patients, a significant increase (>0.3) in the Delta OD occurred prior to an increase in intracranial pressure or a change in the neurological examination, or a change on CT scan. Early diagno sis using NIBS may allow early treatment and reduce secondary injury c aused by delayed hematomas.