Porencephaly is an uncommon cerebral disorder in animals with almost nonexistent reports in dogs
]. Seizures have been documented in animals with congenital abnormalities such as hydrocephaly, lissencephaly, and porencephaly
In dogs, brain anomalies could be related to seizures in a low percentage of cases (4.16%)
], however there are only few previous reports of seizures associated with porencephaly in this species
]. On the other hand, seizures as consequence of idiopathic epilepsy are the most common brain disease in dogs
]. Furthermore, reports of epilepsy due to focal cortical dysplasia in animals, as well as descriptions of neuronal malformation, are rare
]. Although there is not a clear correlation between porencephaly and seizures, authors reported that porencephaly is often accompanied by amygdalar-hippocampal atrophy, which is usually related to the occurrence of seizures
]. Hippocampal atrophy was also noticed in the case reported herein.
The main clinical manifestation of porencephaly is the occurrence of seizures
], whereas the other clinical signs that the dog presented with, such as ataxia, dysmetria, intention tremors are related to vestibulo-cerebellar abnormalities
]. Further association between vestibulo-cerebellar signs and porencephaly was observed in dogs and cats by Schmidt et al.
], but without any noticeable cerebellar lesion. In the case reported herein it was detected a focal cerebellar vermis atrophy as well as low cellularity of the granule cell layer, which may be associated to the vestibulo-cerebellar signs, since cerebellar abnormalities associated with ataxia are frequently described in dogs, including degeneration, hypoplasia and localized defects
In this case, CSF evaluation was normal. The dog had anesthetic complications without any apparent cause and died, and according to Gaynor et al.
], it is a rare condition that might be associated with hypotension or cardiac dysrhythmias. The generic clinical signs render difficult the diagnosis of porencephaly; for humans, there is the possibility of mutation identification by molecular research
], however, this is currently not applicable for animals.
The major gross alteration presented herein is consistent with porencephaly. We also found cerebral neuronal dysplasia and cerebellar vermis focal atrophy. Even though porencephaly has been associated with viral infections and nutritional deficit in ruminants and vascular disturbs in humans, the specific cause in dogs remains undetermined
]. Viral infection is thought to affect endothelial cells during pregnancy and consequently causes vascular lesion and extensive loss of brain tissue, leading to the formation of cavitations
]. Furthermore, the paucity of case reports make impossible to attribute this condition to a genetic predisposition of a specific breed. Consequently, since no cause could be determined, we describe herein a case of encephaloclastic (destructive) porencephaly, as suggested by Schmidt et al.