holoprosencephaly
Pronunciation: hol-oh-pros-en-SEF-ah-lee
A severe brain malformation where the forebrain fails to divide into distinct hemispheres, often associated with midline facial defects.
Full Definition
Holoprosencephaly is a complex brain malformation resulting from the failure of the prosencephalon (forebrain) to properly divide into bilateral cerebral hemispheres during early embryonic development. This condition exists on a spectrum from mild (lobar) to severe (alobar) forms, with varying degrees of fusion of brain structures and associated facial abnormalities. The condition often presents with developmental delays, seizures, and hormonal dysfunction due to hypothalamic-pituitary involvement. Editors should note the distinct spelling and avoid confusion with other developmental brain disorders.
Usage
Usage note: Always lowercase unless beginning a sentence. Often abbreviated as HPE in clinical notes.
In Context
- "The fetal MRI revealed alobar holoprosencephaly with absence of the interhemispheric fissure." — Prenatal diagnostic report
- "Children with holoprosencephaly often require multidisciplinary care including neurology, endocrinology, and genetics." — Treatment planning document