Microencephalia vs. Anencephaly

Left picture: There is a microcephaly on hand which is caused by a microencephaly. The microcephaly is the contrary of a macrocrania. The diagosis is established on a value of head circumference below the third percentile and a discrepancy between the facial skull and the neurocranium. This primary microencephalia is based on a prenatal cause. Right picture: The diagnosis in this case is an anencephaly. The neurocranium and the hemispheres are missing. The reddish soft tissue masses correspond to residuals of brain structure. Besides the myelomeningocele and encephalocele, the anencephaly belongs to the third-frequent dsyrhaphic malformation which is recognized by determining the alpha-fetoprotein in the amniotic fluid. Anencephalic neonates may sometimes survive for a couple of weeks.

In both neonates the neurocranium is deficiently developed in comparison to the facial skull. Left picture: The newborn who seems looking at the examiner has vigorously developed hair somewhat covering the short forehead. Right picture: In this newborn the eyes are nearly closed in spite of the distinctly prominent bulbi. The neurocranium is missing; so is robust hair, and the discrepancy between the facial skull and the absent neurocranium is very striking, especially if considering the relatively large auricles. At the top of the head reddish soft tissue structures are recognizable.