ISSN:
1432-1203
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary Morphological investigations were carried out on brains of 274 foetuses and children with a verified chromosomal anomaly. In more than two thirds of these cases pathological changes were not detectable. In the other cases the most frequent findings were: (1) holoprosencephaly/arhinencephaly, mainly observed in trisomy 13, but also in one case each of trisomy 18 and trisomy 21; (2) corpus callosum defects, mainly found in trisomy 18, but also in some cases of trisomies 13 and 21; (3) cerebellar nerve cell heterotopias and cerebral microdysplasias, present mainly in trisomy 21, but also in trisomies 13 and 18 as well as in cases with different chromosomal syndromes; (4) small hamartomas of the brain stem were found in two cases of trisomy 18. In a control group of 85 cases with “multiple malformations”, but without a verified chromosomal anomaly, similar observations were recorded. In particular, in a subgroup of cases with ascertained normal karyotype (31 out of 85 cases) seven holoprosencephalies, four corpus callosum defects, eight cerebellar heterotopias as well as three cerebral cortical microdysplasias and three stenoses of the aqueduct were found. It thus seems reasonable to assume that structural alterations of the central nervous system (CNS) are neither constant nor obligatorily accompanying a specific chromosomal syndrome. However, their appearance follows patterns of semi-specificity. On the other hand, one has to realize that in about one third of holoprosencephalies no chromosome anomaly is present. Moreover, cerebellar nerve cell heterotopias cannot be considered as “true” malformations, since they are very frequently found in normal newborns (mostly prematures), and disappear progressively with increasing age (“transitional microdysplasias”).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00281680
Permalink
