Growth restriction and the cerebral metabolic response to acute hypoxia of chick embryos in-ovo: a proton magnetic resonance spectroscopy study.

Introduction: Perinatal brain injury is more common in growth-restricted (GR) than normally grown (NG) fetuses. This study addresses the hypothesis that chronic oxygen and substrate deprivation during pregnancy will engender an abnormal fetal cerebral metabolic response to acute hypoxia.

Method: Cerebral metabolite resonance amplitudes relative to that of creatine were measured by proton magnetic resonance spectroscopy in chick embryos on day 19 of incubation.

Magnetic resonance proton spectroscopy and diffusion weighted imaging of chick embryo brain in ovo.

Metabolic compensatory mechanisms may partly account for the decreased vulnerability to hypoxia observed in the developing brain. We used proton magnetic resonance spectroscopy and diffusion-weighted imaging to measure the cerebral concentrations of lactate and other metabolites, as well as the apparent diffusion coefficient (ADC) of tissue water, before, during and after hypoxia in anaesthetised chick embryos in ovo. Reducing the inspired oxygen concentration to 8% for 40 min caused a significant rise in both mean (+/-S.