Value of assessment of multivoxel proton chemical shift imaging to predict long term outcome in patients after out-of-hospital cardiac arrest: A preliminary prospective observational study

Abstract Background Existing methods to predict recovery after out-of-hospital cardiac arrest (OHCA) lack of accuracy. The aim of this study was to determine whether quantitative proton chemical shift imaging ( 1 H-CSI) during the subacute stage of OHCA can predict neurological outcome of such patients. Methods This monocentric prospective observational study was conducted in a Intensive Care Unit of a teaching hospital. Forty consecutive patients with OHCA were enrolled between January 1st 2011–December 31st 2013. Multivoxel 1 H-CSI values were compared to structural magnetic resonance imaging (MRI) sequences (fluid-attenuated inversion recovery and diffusion-weighted imaging). Ratios of N -acetyl-aspartate (NAA) to creatine (Cr) and choline compounds were analyzed using region of interest in bilateral lenticular cores and thalami. The outcome evaluated was the Cerebral Performance Category (CPC) at 6 months, dichotomized as favorable (CPC 1-2) and unfavorable outcome (CPC 3-5). The performance was compared by area under the receiver operating characteristic (ROC AUC ) curves analysis. Results Twenty nine OHCA had an interpretable MRI. Eight patients (28%) had favorable outcome at 6 months. The worst NAA/Cr in lenticular cores was the best 1 H-CSI marker, with 80% sensitivity (95% confidence interval (CI), 57–94) and a 100% specificity (95% CI, 63–100) with a positive predictive value of 100%. Prognostic accuracy, as quantified by the ROC AUC , was higher with the worst NAA/Cr in lenticular cores (ROC AUC 0.88; 95% CI, 0.70–0.97) than with the structural MRI sequences. Conclusion In this preliminary study we found that multivoxel 1 H-CSI in lenticular cores was highly predictive of unfavorable outcome at 6 months.