Neuroimaging in Neonatal Nonketotic Hyperglycinemia

Abstract

Nonketotic hyperglycinemia is a fatal disorder of glycine metabolism presenting with intractable epilepsy, hypotonia, and developmental delay in infancy. Diagnostic tests,such as cerebrospinal fluid glycine estimation and genetic diagnostic methods, are not widely available in developing countries and hence many cases are missed or wrongly diagnosed. The magnetic resonance imaging features, such as abnormal signal intensity in the dorsal pons, midbrain, central tegmental tract, cerebral peduncle, and posterior limb of the internal capsule indicate an important clue to the possibility of the disease and help in guiding the treating neonatologist.

Keywords

nonketotic hyperglycinemia - magnetic resonance imaging - central tegmental tract - neonatologist

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