Under normal conditions, the neurons forming a germinal layer around ventricles migrate to the surface of the brain and form the cerebral cortex and basal ganglia. If this process is abnormal or disturbed it could result in the enlargement of the occipital horns of the lateral ventricles. Common prenatal disturbances that have been shown to disturb the neuronal migration process include the following:
continuation of oral contraceptives
exposure to alcohol
intrauterine malnutrition
intrauterine infections such as toxoplasmosis
maternal drug ingestion during early pregnancy such as corticosteroids, salbutamol, and theophyllineResearchers also believe that these factors can cause destruction of neural elements that have previously been normally formed.It is suggested that the underdevelopment or lack of white matter in the developing fetus could be a cause of colpocephaly. The partial or complete absence of white matter, also known as agenesis of the corpus callosum results in anatomic malformations that can lead to colpocephaly. This starts to occur around the middle of the second month to the fifth month of pregnancy. The lateral ventricles are formed as large cavities of the telencephalic vesicle. The size of the ventricles are decreased in normal development after the formation of the Foramen of Magendie, which decompresses the ventricular cavities. Myelination of the ventricular walls and association fibers of the corpus callosum and the calcarine fissure helps shape the occipital horns. In cases where this developmental process is interrupted, occipital horns are disproportionately enlarged.Colpocephaly has been associated with chromosomal abnormalities such as trisomy 8 mosaic and trisomy 9 mosaic.
Dolichocephaly (derived from the Ancient Greek δολιχός long and κεφαλή head) is a condition where the head is longer than would be expected, relative to its width. In humans, scaphocephaly is a form of dolichocephaly. Dolichocephalic dogs (such as German Shepherds) have elongated noses. This makes them vulnerable to fungal diseases of the nose such as aspergillosis. In humans the anterior–posterior diameter (length) of dolichocephaly head is more than the transverse diameter (width).It can be present in cases of Sensenbrenner syndrome, Crouzon syndrome, Sotos syndrome, CMFTD as well as Marfan syndrome. See also
Brachycephaly
Cephalic index
Plagiocephaly

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