Objective
To clarify the pathogenetic significance of the topographic distribution of leptomeningeal glioneuronal heterotopia, a common finding in holoprosencephaly.
Design
Gross, histological, and immunohistochemical observations of alobar holoprosencephaly in brain specimens taken at autopsy.
Setting
Referral center.
Materials
Brains removed at autopsy from five consecutive patients with alobar holoprosencephaly.
Main Outcome Measures
Immunoperoxidase staining for glial fibrillary acidic protein.
Results
In all brains, leptomeningeal glioneuronal heterotopia showed an identical distribution, ranging from the basal prosencephalon to the pons, with the thickest distribution occurring in the basal prosencephalon.
Conclusion
The constant localization implicates leptomeningeal glioneuronal heterotopia in severe dysgenesis of midline prosencephalon, the basic pathogenesis of the anomaly.
