Evidence From Proton Magnetic Resonance Spectroscopy for a Metabolic Cascade of Neuronal Damage in Shaken Baby Syndrome

Abstract

Objective. The purpose of this study was to use proton magnetic resonance spectroscopy (MRS) as a metabolic assay to describe biochemical changes during the evolution of neuronal injury in infants after shaken baby syndrome (SBS), that explain the disparity between apparent physical injury and the neurological deficit after SBS. Methodology. Three infants [6 months (A), 5 weeks (B), 7 months (C)] with SBS were examined repeatedly using localized quantitative proton MRS. Examinations were performed on days 7 and 13 (A), on days 1, 3, 5, and 12 (B), and on days 7 and 19 (C) posttrauma. Long-term follow-up examinations were performed 5 months posttrauma (A) and 4.6 months posttrauma (B). Data were compared to control data from 52 neurologically normal infants presented in a previous study. Results. Spectra from parietal white matter obtained at approximately the same time after injury (5 to 7 days) showed markedly different patterns of abnormality. Infant A shows near normal levels of the neuronal marker N-acetyl aspartate, creatine, and phosphocreatine, although infant C shows absent N-acetyl aspartate, almost absent creatine and phosphocreatine, and a great excess of lactate/lipid and lipid. Analysis of the time course in infant B appears to connect these variations as markers of the severity of head injury suffered in the abuse, indicating a progression of biochemical abnormality. The principal cerebral metabolites detected by MRS that remain normal up to 24 hours fall precipitately to ∼40% of normal within 5 to 12 days, with lactate/lipid and lipid levels more than doubling concentration between days 5 and 12. Conclusions. A strong impression is gained of MRS as a prognostic marker because infant A recovered although infants B and C remained in a state consistent with compromised neurological capacity. Loss of integrity of the proton MR spectrum appears to signal irreversible neurological damage and occurs at a time when clinical and neurological status gives no indication of long-term outcome. These results suggest the value of sequential MRS in the management of SBS.

N-Acetylaspartate in the CNS: From neurodiagnostics to neurobiology

“…However, the heterogeneous nature of the neuropathological response to trauma has stimulated interest in other interpretations. In infants subject to "shaken baby syndrome" loss of NAA appears to follow a cascade of neurochemical events in which activated phospholipases are hypothesized to release lipids and macromolecules visible in the proton brain spectrum (Haseler et al, 1997). Childhood traumatic brain injury may result in a reversible loss of NAA which recovers approximately with the time-scale of recovery from the syndrome of inappropriate anti-diuretic hormone (SIADH) (Ross et al, 1998).…”

Imaging of head injuries in infants: temporal correlates and forensic implications for the diagnosis of child abuse

“…Furthermore, both these groups mainly addressed adults, in whom SDHs differ markedly from infantile SDHs. 29 Surprisingly, these results were neither confirmed nor questioned, whereas several new reports on infantile SDH studied using sophisticated techniques, such as diffusion MR imaging 7,27 or MR spectroscopy, 16,18 have appeared in the radiological literature. The paucity of studies involving precise datingrelated data may be explained by the difficulties in obtaining synoptic radiological, judicial, clinical, and surgical data.…”

Advancements in Imaging Technology: Do They (or Will They) Equate to Advancements in Our Knowledge of Recovery in Whiplash?

“…As the strength of the magnetic field increases, the separation between peaks and signal to noise with MRS improves, providing a more robust environment in which to noninvasively evaluate cellular biochemistry following head/neck trauma-and possibly add to the prediction of recovery. There is evidence from MRS-based studies toward the prediction of neurologic recovery from pediatric trauma ("shaken-baby" syndrome) 51 and the identification of biomarkers in spondylosis. 107 Preliminary evidence from a small cohort of individuals with persistent whiplash-associated pain suggests that biochemical changes in the central nervous system could be present.…”