Dyke-Davidoff-Masson syndrome (DDMS) is a rare entity that presents with atrophy/hemicerebral hypoplasia secondary to brain injury,
usually in the fetal period or in early childhood,
and is accompanied by ipsilateral compensatory bone hypertrophy and contralateral hemiparesis.
There are two types of DDMS: congenital (infantile) and acquired (during early life due to brain damage,
usually traumatic).
Prenatal causes include congenital abnormalities,
cerebral infarction,
vascular malformations,
infections,
and gestational vascular occlusion,
primarily involving the middle cerebral vascular territory.
Birth trauma,
hypoxia,
intracranial hemorrhage,
tumors,
infections,
and prolonged febrile seizures after birth are important peri/post-natal causes.
It can also be due to decreased carotid artery blood flow due to coarctation of the aorta.
In congenital hemiatrophy,
when the injury occurs in utero,
there is a shift of midline structures toward the side of the disease,
and the sulcal prominence replacing the gliotic tissue is absent.
This feature differentiates it from cerebral hemiatrophy which occurs in early life.
The atrophied cerebral hemisphere will have prominent sulcal spaces if the damage occurs after birth or after the end of sulcation.
When hypoplasia of one cerebral hemisphere exists,
ipsilateral compensatory changes occur in the skull,
consisting of thickening of the diploe,
enlargement of the paranasal sinuses (mainly frontal) and mastoid cells,
elevation of the petrous portion of the temporal bone,
sphenoid wing and orbital roof,
decrease in the size of the middle and anterior cranial fossae and displacement of falx attachment.
This syndrome is clinically characterized by difficult-to-control epilepsy,
different degrees of facial asymmetry,
contralateral hemiplegia or hemiparesis and various degrees of mental retardation,
which is not always present.
In some cases,
speech disorders have also been described.