Congenital Fusion of the Thalami (Atresia of the Third Ventricle) Associated with Parietooccipital Meningocele

Abstract

In this article we present a case of a male newborn with a CNS malformation that is characterized mainly by complete fusion of the thalami resulting in atresia of the 3rd ventricle accompanied by fusion of the anterior peduncles of the fornix, the presence of a single occult interventricular foramen lying at the midline, absence of the septum pellucidum, hypoplasia of the corpus callosum, disorganization of the head of the left caudate nucleus, and greatly dilated lateral ventricles (hydrocephalus). The patient underwent surgical correction of the meningocele on his 4th postnatal day. On his 13th postnatal day he had projectile vomiting due to a left parietooccipital hygroma that was drained via a shunt. On his 31st postnatal day he developed seizures and marked dilatation of the lateral ventricles, for which he underwent a ventriculoperitoneal shunt (Brown). On the 14th postoperative day the patient developed aspiration pneumonia and died.

Masses and Malformations of the Third Ventricle: Normal Anatomic Relationships and Differential Diagnoses

“…Congenital malformations and lesions of the third ventricle cover a spectrum of anomalies. Atresia of the third ventricle is rare, results from thalamic fusion, and is associated with other malformations of midline intracranial structures and lateral ventricular dilatation (8). The most common cause of an abnormal contour of the third ventricle is a dilated third ventricle with congenital hydrocephalus.…”