Postencephalitic porencephaly, hydranencephaly or polymicrogyria. A review

Abstract

Twenty necropsy cases of the association of fetal encephalitis with porencephaly, hydranencephaly or polymicrogyria were reviewed including 5 from the authors' material. The latter include a basket brain, a porencephalic necrosis of recent date and a polymicrogyria in the formative state. The supratentorial lesions are often associated with cerebellar cortical dysplasias. The pathogenetic interdependence of encephalitis and hemispheric defects or malformation is discussed. Examples are given in which the infection appears to be secondary to a pre-existent hemispheric lesion. For others the hemispheric lesions appear to be secondary to encephalitis. In these the encephalitis may produce secondary lesions by a variety of pathogenetic mechanisms.

Hydranencephaly with extensive periventricular necrosis and numerous ectopic glioneuronal nests

“…Furthermore, it was noteworthy that numerous ependymal rosettes were present in the periventricular region. Periventricular lesions with ependymal rosettes in the brainstem have been reported in two out of 23 autopsy cases of hydranencephaly described in the published literature 1,6–15 . One of these two cases was a severe form of hydranencephaly, as in the present case, showing absence of most of the cerebral cortex and a relatively preserved brainstem 9 .…”

Developmental dyslexia: a multilevel syndrome

“…There is also a suggestion that more ectopias are present in the left than in the right hemisphere. Similar ectopias have been seen in other developmental disorders in humans, including the foetal alcohol syndrome and many mental retardation syndromes (Friede and Mikolasek, 1978), although we are not aware that the distribution and numbers of the malformations are equivalent.…”

Multiple thromboembolic events in fetofetal transfusion syndrome in triplets contributing to the understanding of pathogenesis of hydranencephaly in combination with polymicrogyria

“…Hydranencephaly is characterized by fetal hemispheric necrosis of the brain that usually presents as 0046 residual defects at birth. An infectious genesis in the form of fetal encephalitis has been proposed as a possible origin of hydranencephaly [3]. Others attributed the pathologic changes to a proliferative vasculopathy [4].…”