Holoprosencephaly is a condition characterized by the failure of embryonic forebrain, called prosencephalon. The forebrain fails to divide into the double lobes of the cerebral hemisphere. As a result, the single-lobed brain structure is formed and severe skull and facial defects appear. The symptoms of holoprosencephaly range from mild to moderate to severe.
Holoprosencephaly Types
The most serious form of holoprosencephaly is alobar holoprosencephaly. In this, the brain fails to separate but there are severe facial anomalies.
Semilobar holoprosencephaly is another form of holoprosencephaly in which the brain's hemispheres have somewhat divided.
Lobar holoprosencephaly is another complication with symptoms of separate brain hemispheres; however, a patient's brain may be nearly normal.
Syntelencephaly affects the posterior frontal lobe and the parietal lobe, which are usually are not properly separated.
Treatment and Prognosis
There is no standard course of treatment for holoprosencephaly. Treatment is symptomatic and supportive. The prognosis for holoprosencephaly depends on the severity of the brain and facial deformities. In most of the cases, the malformations take a severe shape leading to the death of the child before birth. In some cases, the babies are born with less severe deformities and have normal or near-normal brain development and facial deformities that have an effect on the eyes, nose and upper lip.