A rare neural tube defect during pregnancy, resulting in the absence of a large portion of the brain and skull in the fetus.
Definition (MSH)
A malformation of the nervous system caused by failure of the anterior neuropore to close. Infants are born with intact spinal cords, cerebellums, and brainstems, but lack formation of neural structures above this level. The skull is only partially formed but the eyes are usually normal. This condition may be associated with folate deficiency. Affected infants are only capable of primitive (brain stem) reflexes and usually do not survive for more than two weeks. (From Menkes, Textbook of Child Neurology, 5th ed, p247)
Definition (CSP)
congenital malformation of the nervous system caused by failure of the anterior neuropore to close; infants are born with intact spinal cords, cerebellums, and brainstems, but lack formation of neural structures above this level; the skull is only partially formed but the eyes are usually normal; affected infants are only capable of primitive reflexes and usually do not survive for more than two weeks; complete absence of the brain is rare.
Brain tissue herniation through a congenital or acquired defect in the skull. The majority of congenital encephaloceles occur in the occipital or frontal regions. Clinical features include a protuberant mass that may be pulsatile. The quantity and location of protruding neural tissue determines the type and degree of neurologic deficit. Visual defects, psychomotor developmental delay, and persistent motor deficits frequently occur.
Definition (NCI)
A congenital neural tube closure defect resulting in the protrusion of the brain through a skull opening. When the protrusion includes the meninges, the term encephalomeningocele is used.