Holoprosencephaly
Holoprosencephaly (
HPE) is a condition that affects the
brain and the
mid-line organs such as the
heart,
eyes, and
kidneys. It results from failure of the
prosencephalon to
cleave into the
cerebral and
lateral hemispheres. It is found in 1:16000
live-born children.
There are three types of HPE:
Lobar - where there are two
lobes in the brain.
Semi-Lobar - where there are two lobes to the rear but not the front of the brain.
Alobar - where there are no lobes at all.
HPE can be:
Familial - it can be caused by a
genetic problem in one or both sides of the parental families. This is what your
geneticist is for. If you don't have one, then ask your own doctor to get you in touch with one.
Environmental - "they" just don't know. Loads of causes have been sited from dry cleaning fluid to
alcohol. The best thing here is not to blame yourself, and not to worry too much about cause in the early days.
HPE is related to:
Microcephaly - a general term given when the head size of the child is said to be below the 5th
centile of what is seen to be normal growth. These "centiles" are different depending on where you live and who calibrated the
ultra-sound scanner. So don't go getting worried too early. However, if you are scanned and the head of your baby is found to be significantly smaller than expected, it is a good idea to have a further set of tests to assess the liklihood of HPE.
Hydracephaly - is usually defined as the presence of excessive
cerebral spinal fluid (
CSF) within the
cranium. However, this situation is sometimes referred to as
dilated ventricles, and
hydrocephalus is restricted for use only when
intracranial pressure is increased.
Congenital hydrocephalus occurs in .3 to .8 per 1,000 births.
Syptoms
variable degrees of
mental retardation
epilepsy
endocrine abnormalities
abnormalities of other organ systems such as
cardiac,
skeletal,
genitourinary, and
gastrointestinal organs.
Mild forms of
facial abnormalities may include a
flat single-nostril nose (
cebocephaly), close set eyes (
hypotelorism),
cleft lip and/or
palate, or just one upper middle tooth (single
maxillary central
incisor).
More severe facial
deformities may include a single central eye (
cyclopia), a nose located on the forehead (
proboscis), or
missing facial features.
More Information: www.hopkins-id.edu/