Longitudinal MR findings in a patient with hemimegalencephaly associated with tuberous sclerosis
Hiroshi Sakuma1, Ohsuke Iwata, Masayuki Sasaki
1Department of Child Neurology, National Center Hospital for Mental, Nervous and Muscular Disorders, NCNP, 4-1-1 Ogawahigashi-cho, Kodaira, Tokyo 187-8551, Japan.
Insights
This study reports a rare case of tuberous sclerosis complex (TSC) with hemimegalencephaly, detailing the progressive atrophy and calcification of the affected hemisphere and associated epilepsy. The underlying cause of these atrophic changes remains unclear.
Area of Science:
- Neuroscience
- Developmental Biology
- Genetics
Background:
- Tuberous sclerosis complex (TSC) is a genetic disorder characterized by the growth of hamartomas in various organs.
- Hemimegalencephaly is a congenital condition where one cerebral hemisphere is disproportionately enlarged.
- The co-occurrence of TSC and hemimegalencephaly is rare, presenting unique diagnostic and therapeutic challenges.
Observation:
- A neonate presented with right hemimegalencephaly and faint periventricular calcification on CT scan.
- MRI revealed T1 and T2 shortening in the affected hemisphere, consistent with transmantle dysplasia.
- Progressive atrophy of the right hemisphere was observed from 6 months to 3 years of age, with increasing calcification.
Findings:
- The patient developed frequent partial motor seizures and infantile spasms, indicative of severe epilepsy.
- Electroencephalogram showed reduced background activity in the right frontal lobe.
- Despite imaging and clinical data, the etiology of the progressive atrophic changes in the hemimegalencephalic hemisphere, potentially a hamartomatous lesion, is undetermined.
Implications:
- This case highlights the complex interplay between genetic disorders like TSC and brain development abnormalities.
- Understanding the pathogenesis of such associations is crucial for developing targeted therapies.
- Further research is needed to elucidate the mechanisms driving progressive atrophy in hemimegalencephaly associated with TSC.
Abstract:
A patient with an unusual association between tuberous sclerosis complex and hemimegalencephaly is reported. At 2 days of age, CT scan disclosed right hemimegalencephaly with periventricular faint calcification. At 1 month of age, magnetic resonance imaging showed right hemimegalencephaly with T1 and T2 shortening. The right frontal and parietal lobes were compatible with transmantle dysplasia. At 6 months of age, the right hemisphere had decreased in size. Atrophic changes continued to progress until 3 years of age. Periventricular calcification in the right hemisphere became marked with age. The patient developed frequent partial motor seizures from 6 weeks of age and infantile spasms from 5 months of age. Electroencephalogram revealed low amplitude of background activities in the right frontal area. The cause of this atrophic change in the hemimegalencephalic hemisphere, which could be a hamartomatous lesion, remains unknown.
