MAGNETIC-RESONANCE SPECTROSCOPY IN HYPOXIC-ISCHEMIC ENCEPHALOPATHY

In vivo magnetic resonance spectroscopy (MRS) allows repetitive, nonin vasive measurement of cerebral metabolites, including ATP, phosphocrea tine (PCr), inorganic phosphate (Pi), intracellular pH, lactate, and N -acetyl aspartate. MRS has been used extensively to study cerebral met abolic changes in neonatal neurologic disorders. In babies with severe hypoxic-ischemic encephalopathy, PCr decreases and Pi increases, caus ing a fall in PCr/Pi and PCr/ATP, and a rise in Pi/ATP. These changes correlate with neurodevelopmental outcome. Decreased ATP is only seen in extremely severe hypoxic-ischemic encephalopathy and is usually ass ociated with death in the neonatal period. Serial MRS studies may be h elpful in selecting babies who would benefit from interventional treat ment. Ongoing advances in MRS technology will permit localized, multin uclear spectroscopy, improving our ability to identify cerebral metabo lic changes.