Abstract
Inherited neurotransmitter disorders are rare neurometabolic conditions which encompass
genetic disorders of neurotransmitter metabolism or transport. The clinical manifestations
of these rare disorders are often nonspecific, ranging from encephalopathies and seizures
to movement disorders. As a consequence, neurotransmitter disorders are underrecognized
and often misdiagnosed. Accurate and timely diagnosis is, however, of utmost importance,
given the availability of therapeutic strategies. A high index of clinical suspicion
and familiarity with the neuroimaging phenotypes is therefore crucial. While the imaging
features of various neurotransmitter disorders often overlap and are nonspecific,
imaging can be helpful in providing useful clues to guide the diagnostic algorithm
for uncommon conditions in a neonate presenting with nonspecific neurological symptoms.
In this review paper, we aim to bring together current knowledge of neuroimaging phenotypes
associated with inherited (primary) disorders of neurotransmitter biosynthesis. Magnetic
resonance imaging phenotypes of disorders of monoamine biosynthesis, primary cerebral
folate deficiency, disorders of pyridoxine metabolism, disorders of gamma-aminobutyric
acid metabolism, nonketotic hyperglycinemia (glycine encephalopathy), disorders of
serine biosynthesis, and cerebral creatine deficiency syndrome will be discussed and
illustrated with case examples.
Keywords
neurotransmitter disorders - neuroimaging - monoamine biosynthesis - pyridoxine metabolism
- glycine encephalopathy - cerebral creatine deficiency
