title: Mechanism of Traumatic Brain Injury at Distant Locations After Exposure to Blast Waves: Preliminary Results from Animal and Phantom Experiments.
abstract: Purpose Primary blast-induced traumatic brain injury (bTBI) is the least understood of the four phases of blast injury. Distant injury induced by the blast wave, on the opposite side from the wave entry, is not well understood. This study investigated the mechanism of distant injury in bTBI. Materials and Methods Eight 8-week-old male Sprague-Dawley rats were divided into two groups: group 1 served as the control group and did not receive any shock wave (SW) exposure; group 2 was exposed to SWs (12.5 ± 2.5 MPa). Propagation of SWs within a brain phantom was evaluated by visualization, pressure measurement, and numerical simulation. Results Intracerebral hemorrhage near the ignition site and elongation of the distant nucleus were observed, despite no apparent damage between the two locations in the animal experiment. Visualization, pressure measurement, and numerical simulation indicated the presence of complex wave dynamics accompanying a sudden increase in pressure, followed by negative pressure in the phantom experiment. Conclusion A local increase in pressure above the threshold caused by interference of reflection and rarefaction waves in the vicinity of the brain-skull surface may cause distant injury in bTBI.
authors.affiliation: Department of Neurosurgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan. nakg_neurosurg@yahoo.co.jp.
authors.forename: Atsuhiro
authors.initials: A
authors.lastname: Nakagawa
authors.affiliation: Institute of Fluid Science, Tohoku University, Miyagi, Japan.
authors.forename: Kiyonobu
authors.initials: K
authors.lastname: Ohtani
authors.affiliation: Department of Chemistry, School of Science, University of Tokyo, Tokyo, Japan.|Department of Electrical Engineering, University of California, Los Angeles, USA.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Goda
authors.affiliation: Department of Emergency Medicine and Critical Care, Tohoku University Graduate School of Medicine, Miyagi, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kudo
authors.affiliation: Division of Electrical and Mechanical Engineering, School of Science and Engineering, Tokyo Denki University, Tokyo, Japan.
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Arafune
authors.affiliation: National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan.
authors.forename: Toshikatsu
authors.initials: T
authors.lastname: Washio
authors.affiliation: Department of Neurosurgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan.
authors.forename: Teiji
authors.initials: T
authors.lastname: Tominaga
mesh_terms: D000818:Animals; D001753:Blast Injuries / Q000209:etiology* / Q000473:pathology; D001921:Brain / Q000473:pathology; D000070642:Brain Injuries, Traumatic / Q000209:etiology* / Q000473:pathology; D003198:Computer Simulation; D005107:Explosions; D008297:Male; D019047:Phantoms, Imaging; D011312:Pressure; D051381:Rats; D017207:Rats, Sprague-Dawley
keywords: Blast injury; Neurocritical care; Shock wave; Traumatic brain injury