[Diagnostic efficacy and pitfalls of a 64-raw multislice computed tomography scan for mild head injuries in children].

The aim of this study is to analyze the usefulness of 64-raw multislice computed tomography (CT) scans and bone images of three-dimensional CT (3D-CT) scans for evaluation of mild head injuries in children. Thirteen children (9 boys and 4 girls, less than or equal to 15 years old) with mild head injury were included in the study. Head CT scans obtained within 24 hours after injury. All children had no episodes of loss of consciousness, amnesia, epilepsy, vomiting, and no neurological abnormality on arrival at hospital. We detected 9 positive findings on CT scans, which looked like fracture lines at the frontal bone in 7 cases. The bone images of CT axial views revealed a true fracture in one case in which a skull X-ray could not demonstrate a fracture line, but, other positive findings turned out to be a diploic vein surrounded by a thin bone cortex. All false positive findings were detected in the patients under the age of 6. By the 3D-reconstructive CT scan, it is easier to detect not only the intracranial lesions but also the cranial fracture. But, the diploic vein is apt to be misdiagnosed as the fracture line, especially in patients under the age of 6.

The fate of Nissl-stained dark neurons following traumatic brain injury in rats: difference between neocortex and hippocampus regarding survival rate.

We studied the fate of Nissl-stained dark neurons (N-DNs) following traumatic brain injury (TBI). N-DNs were investigated in the cerebral neocortex and the hippocampus using a rat lateral fluid percussion injury model. Nissl stain, acid fuchsin stain and immunohistochemistry with phosphorylated extracellular signal-regulated protein kinase (pERK) antibody were used in order to assess posttraumatic neurons. In the neocortex, the number of dead neurons at 24 h postinjury was significantly less than that of the observed N-DNs in the earlier phase. Only a few N-DNs increased their pERK immunoreactivity. On the other hand, in the hippocampus the number of dead neurons was approximately the same number as that of the N-DNs, and most N-DNs showed an increased pERK immunoreactivity. These data suggest that not all N-DNs inevitably die especially in the neocortex after TBI. The fate of N-DNs is thus considered to differ depending on brain subfields.