Porencephaly is a relatively rare condition characterized by a defect or cavity in the brain which often communicates with the ventricular system and subarachnoid space and is filled with cerebrospinal fluid. Although the condition is well documented in the neurologic and roentgenologic literature, the ocular manifestations have been reported only rarely by ophthalmologists. Because of this, it was thought worth while to present the following review of the subject and unusual case report.
Even though this condition was known before 1859, it was not until then that Heschl * first applied the term porencephaly to 11 cases in which there was cavity formation in the brain substance communicating with the ventricular system and subarachnoid space. In the course of time, however, the concept of the term has changed, so that today many authors designate any cystic cavity in the brain as porencephaly except in the case of a cystic tumor.
ALPER MG, DESSOFF J. Porencephaly. AMA Arch Ophthalmol. 1955;54(4):541-547. doi:10.1001/archopht.1955.00930020547007