Case studyIomazenil hyperfixation in single photon emission computed tomography study of malformations of cortical development during infancy
Introduction
Malformation of cortical development (MCD) is one of the major causes of intractable childhood epilepsy.1 Defects in some processes of corticogenesis, including migration, proliferation, or differentiation of neurons, can cause diverse types of MCDs. Here, we report 2 cases of patients with severe MCD and early onset epilepsy, who underwent 123I-iomazenil single photon emission computed tomography (SPECT) during infancy. Neither of the patients had received benzodiazepines around the time of the SPECT scans.
Section snippets
Case 1
The patient was a boy with left hemimegalencephaly. His detailed clinical history, including seizure development associated with functional hemispherectomy, has been previously reported.2 He experienced seizures consisting of motion arrest, apnoea, and facial cyanosis at the age of 2 days. Magnetic resonance imaging (MRI) revealed enlargement of and cortical dysplasia in the left cerebral hemisphere (Fig. 1A). The right hemisphere appeared to be normal, except for the slightly blurred
Discussion
In both the patients with severe MCD, 123I-iomazenil SPECT demonstrated abnormal hyperfixation in the lesions during early infancy. During normal development of the brain, postnatal neuronal maturation occurs early in the occipital and central regions and later in the frontal region. This development is corroborated by a synchronous progression of myelination and an increase in regional cerebral blood flow, which can be detected by MRI and SPECT. The images of the control infants in this study
Acknowledgement
We are deeply grateful to Dr. Mitsuhiro Kato, at the department of pediatrics, Yamagata University School of Medicine, for the genetic analysis of the doublecortin gene.
None of the authors has any conflict of interest to disclose.
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