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Mark G. Hamilton and S. Terence Mylks

✓ Injury to the spinal column and spinal cord occurs relatively infrequently in the pediatric population. A review of 174 pediatric patients is presented, representing 5.4% of all patients admitted with spinal injury, Spinal cord injury was present in 45% of patients. A distinct injury profile, explained by anatomical and biomechanical features, distinguishes the young patient with an immature spine from older adolescents with a more mature, adult-like spine. The younger patients, while less likely to have spinal injury, had a higher incidence of neurological injury, in addition to a higher frequency of both spinal cord injury without radiological abnormality and upper cervical cord injury. In addition, younger patients with spinal cord injury and no radiological abnormality were more likely to have complete or severe cord injury. Prognosis was determined by the severity of spinal cord injury. Patients with complete cord injuries showed little improvement, while patients with incomplete injuries generally fared much better, with 74% showing significant improvement and 59% experiencing a complete recovery of neurological functions. There were six deaths, but none was attributed solely to spinal injury. The authors conclude that outcome is quite good after pediatric spinal cord injury that does not produce a physiologically complete cord deficit.

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Mark G. Hamilton and S. Terence Myles

✓ Injury to the spinal column and spinal cord occurs relatively infrequently in the pediatric population. The authors present a unique review of 61 pediatric deaths associated with spinal injury. This group represented 28% of the total pediatric spine-injured population and 45% of the total pediatric spinal cord-injured group studied. The ratio of pediatric to adult spinal injury mortality was 2.5:1. Of the 61 children, 54 (89%) died at the accident scene. Thirty patients underwent a complete autopsy, 19 of whom had an Abbreviated Injury Scale Grade 6 injury (maximum score, untreatable). Spinal cord injury was found to be the cause of death in only eight children and was associated with injury to the high cervical cord and cardiorespiratory arrest. These children typically sustained severe multiple trauma. In this population, there appears to be little room for improved outcome through changes in treatment strategy.

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Mark G. Hamilton, Bruce I. Tranmer, and Roland N. Auer

✓ Insulin has recently been shown to ameliorate damage in models of global brain ischemia. To determine whether insulin is also neuroprotective in focal ischemia, 20 rats were given 2 to 3 IU/kg insulin and 10 did not receive treatment prior to normothermic transient middle cerebral artery occlusion for 2 hours at a blood pressure of 60 mm Hg. To further elucidate whether infarction volume is influenced by variations in blood glucose levels within the physiological range, blood glucose was raised in 10 of the insulin-treated animals to levels comparable with the untreated controls. At 1-week survival, damage was assessed using quantitative neuropathological examination of 25 coronal planes. It was found that preischemic insulin lowered the mean intraischemic blood glucose level from 8.4 ± 0.2 mM (µ ± standard error of the mean) in the control group to 3.4 ± 0.2 mM and reduced total damage (atrophy plus cortical and striatal necrosis), expressed as the percentage of the normal hemisphere, from a control of 28.5% ± 2.9% to 14.5% ± 1.6% (p < 0.005). Coadministration of glucose and insulin resulted in a mean intraischemic blood glucose level of 10.1 ± 0.5 mM, with 27.0% ± 2.4% total damage (p = 0.96, compared with control). Total ischemic damage showed an independent correlation with blood glucose levels (r = 0.67, p = 0.0018).

The findings indicate that insulin benefits transient focal ischemia and that reducing the blood glucose from 8 to 9 mM to the low-normal range of 3 to 4 mM with insulin dramatically reduces subsequent infarction. The data suggest that the neuroprotective mechanism of insulin action in focal middle cerebral artery occlusion is mediated predominantly via alterations in blood glucose levels. In comparison to global ischemia, focal ischemia appears to show only a minor direct central nervous system effect of insulin. In clinical situations in which transient focal ischemia to the hemisphere can be anticipated, insulin-induced hypoglycemia of a mild degree may be beneficial.

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Mark G. Hamilton, Douglas J. Demetrick, Bruce I. Tranmer, and Bernadette Curry

✓ A 60-year-old man presented with progressive and unique neurological symptoms. Investigations identified an isolated cerebellar lesion. This lesion fulfilled the histological criteria for lymphomatoid granulomatosis, and in situ hybridization and deoxyribonucleic acid (DNA) dot blot techniques revealed significant amounts of Epstein-Barr virus DNA within the tumor cells. The patient underwent cranial radiation therapy, and 16 months after the initial presentation the lesion evolved into a malignant lymphoma. He subsequently died secondary to subdural empyema, bacterial meningitis, and bronchopneumonia. The unique clinical and etiological aspects of this case are addressed.

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May N. Tsao, Michael L. Schwartz, Mark Bernstein, William C. Halliday, Alex W. Lightstone, Mark G. Hamilton, Satish Jaywant, and Normand Laperriere

✓ Capillary hemangiomas are rare benign vascular tumors that tend to occur in children. Whereas the majority of hemangiomas may regress spontaneously, those associated with functional sequelae or severe symptoms may require treatment. Two patients with capillary hemangiomas of the cavernous sinus that caused neurological symptoms were treated with fractionated stereotactic radiation therapy. Both hemangiomas had shown a progressive increase in size during observation before radiation therapy; both tumors regressed after radiotherapy. Up to the time of the last follow-up evaluation both patients experienced symptomatic relief after radiation. One patient's tumor remains in complete remission and the second tumor continues to demonstrate minor residual contrast enhancement without progression.

The authors conclude that fractionated stereotactic radiation therapy is a useful treatment modality in the management of symptomatic capillary hemangiomas when these tumors arise in regions of the brain or skull base in which a complete resection cannot be accomplished.

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Oral Presentations

2010 AANS Annual Meeting Philadelphia, Pennsylvania May 1–5, 2010