Prognostic value of proton magnetic resonance spectroscopy findings in near drowning patients: reversibility of the early metabolite abnormalities relates with a good outcome

Abstract

-In two children with near drowning hypoxic encephalopathy and normal-appearing structural MRI, acute proton magnetic resonance spectroscopy ( 1 H MRS) showed biochemical alterations that correctly indicated prognosis and helped to guide management decisions. Elevation of the lipid-lactate and glutamineglutamate peaks, on the early (72 hour) 1 H MRS, predicts a poor prognosis. Absence of lipid-lactate and glutamine-glutamate peaks on the early 1 H MRS and reversibility of early mild metabolite abnormalities on follow up examination relates with good outcome. The term "near drowning" signifies patient survival for more than 24-hours after cardiorespiratory arrest due to submersion. Early prognostic of good outcome versus significant neurological deficit or death is important for correctly stratifying patient management 1,2 . Magnetic resonance image (MRI) and computed tomographic findings of acute hypoxia ischemic injury are often subtle 1-3 . we describe the findings of early proton magnetic resonance spectroscopy ( 1 H MRS) that helped to predict the prognosis. MetHodIn two children with hypoxic-ischemic insult due to fresh water near drowning and normal-appearing structural MRI are studied.In each patient single-voxel 1.5 Tesla 1 H MRS was performed in the median biparietal-occipital gray matter using a stimulated echo acquisition mode (STEAM) technique with repetition time: 1,500 ms, echo time: 30 ms, eight excitations, volume of interest: 6 cm 3 , and acquisition time: 7 minutes. The 1 H MRS data were compared with the standard MRI study obtained at the same session using non contrast sagittal T1-weighted images (wI), coronal and axial T2-wI, axial T2*-wI, axial T2-FlAIR and axial diffusion-wI, followed by gadolinium-enhanced axial T1-wI. results Case 1This 3-year-old girl suffered near drowning in a swimming pool. She experienced cardiorespiratory arrest, was

Lenticulostriate arterial distribution pathology may underlie pediatric anoxic brain injury in drowning

“…MR spectroscopy (MRS), which provides a metabolic profile of the brain, has been useful in predicting outcomes with drowning and could supplement structural MRI observations. Previous studies suggest that 1H MRS has improved sensitivity when implemented 3–4 days post-drowning (versus 1–2 days), and that the N-Acetyl-Aspartate/Creatine (NAA/Cr) ratio and/or lactate could be potent markers for assessment and prognosis in acute drowning ( Aragao et al, 2009 , Gutierrez et al, 2010 , Nucci-Da-Silva and Amaro, 2009 , Topjian et al, 2012 ). For optimal impact and reasonable scan times, however, a volume of interest should be defined.…”