Early surgical management of antenatal diagnosed cystic lesions of the foramen of Monro causing monoventricular hydrocephalus.

Introduction: After diagnosis of an antenatal monoventricular hydrocephalus caused by a cystic lesion of the foramen of Monro, treatment modality and time frame may be difficult to assess. Previously, this type of hydrocephalus was often treated with internal shunting. The advent of neuroendoscopy has changed the surgical management of this pathology.

Materials And Methods: We report on two cases of cystic lesions of the foramen of Monro discovered on antenatal ultrasonography. A cavum veli interpositi in one case and a choroid plexus cyst in the other were responsible for unilateral hydrocephalus. In both cases, endoscopic treatment before 1 month of age was performed as the primary procedure with a successful outcome.

Conclusions: We advise early endoscopic treatment for newborns presenting with progressive unilateral hydrocephalus caused by a cystic lesion of the foramen of Monro. It has been, in our hands, a safe and efficient procedure.