%0 Journal Article %A PJ Lally %A DL Price %A A Bainbridge %A SS Pauliah %A P Satodia %A SC Wayte %A L Abernethy %A M Turner %A AN Basheer %A A Alavi %A O Kirmi %A B Jones %A S Shankaran %A EB Cady %A S Thayyil %T PC.26 Feasibility of Magnetic Resonance Spectroscopy in Examining Thalamic Metabolite Concentrations in a Multi-Centre Study of Neonatal Encephalopathy %D 2014 %R 10.1136/archdischild-2014-306576.128 %J Archives of Disease in Childhood - Fetal and Neonatal Edition %P A44-A45 %V 99 %N Suppl 1 %X Background Proton magnetic resonance spectroscopy (MRS) has high prognostic value in hypoxic ischaemic encephalopathy (HIE), however its multi-centre application is limited by inconsistencies between scanners and protocols. N-acetylaspartate (NAA) is predominantly neuronal: cerebral NAA concentration may be a more reliable HIE-severity biomarker than lactate/NAA. Objective To quantify the inter-site and inter-subject variability of NAA concentration measurements. Design/Methods We recruited 5 healthy adult volunteers (aged 24–38, 2 male, 3 female) whom we scanned at 3 UK sites participating in a multi-centre neonatal-brain study (University Hospital, Coventry (UHC); Alder Hey Children’s Hospital, Liverpool (AH); University College Hospital, London (UCLH)). Thalamic NAA concentration was measured using the neonatal brain-water concentration reference protocol (15 × 15 × 15mm3 voxel; PRESS; water-suppressed TR/TE = 2s/288&60ms; TR/TE = 5s/60ms; non-water-suppressed TR = 10s, TE = 60/124/205/316/495/1000 ms). Spectra were post-processed in jMRUI and metabolites fitted with LCModel. Results One volunteer was unavailable for scanning at AH. The mean (SD) NAA concentrations across the remaining four subjects were 15.5(3.4)mmol/kg wet weight, 14.4(0.1) mmol/kg wet weight, and 15.2(0.1) mmol/kg wet weight at UHC, AH and UCLH respectively. This corresponds to a maximum inter-site group mean variation (range/mean) of 8%. The inter-subject variability of mean NAA concentration (SD/mean) was 10%. Conclusions The variation of thalamic NAA concentration between sites was 8% and the standard deviation across subjects was 10%, hence [NAA] may be suitable for multi-centre studies. Abstract PC.26 Figure %U https://fn.bmj.com/content/fetalneonatal/99/Suppl_1/A44.3.full.pdf