Hydranencephaly is a term used to describe a rare congenital anomaly of the head which seems to combine features of both hydrocephalus and anencephaly. In this condition, both cerebral hemispheres, apart from imperfectly developed basal gyri, are replaced by a liquor-filled, double bladder, the wall of which consists of the intact meninges. The skull is normal. The midbrain is imperfectly formed, while the lower structures (pons, medulla, and cerebellum) are normal.
The newborn infant with hydranencephaly gives no evidence that his cerebral hemispheres are absent, for during the first few months of life, he exists at a reflex, decorticate level, making it all the more difficult to detect hydranencephaly clinically. Nevertheless, transillumination of the skull made it possible to make antemortem diagnoses of hydranencephaly in 4 infants at ages 6 weeks, 3 weeks, one day, and 4 hours.
Report of Cases
Case 1.—A 3,120 gm. male infant delivered spontaneously July
KALOSS W, KUHNLEIN E. Hydranencephaly. Am J Dis Child. 1962;103(2):177-182. doi:10.1001/archpedi.1962.02080020183013