Iniencephaly: sonographic-pathologic correlation of 19 cases.

During a four year period (1991-1994), 19 cases of iniencephaly were evaluated at our institution. Associated cranial malformations include anencephaly in 15 (79%), and posterior encephalocele in 5 (26.3%) of the cases. Other associated malformations include diaphragmatic defects with a accompanying hernia, omphalocele, gastrointestinal malformations, cardiovascular and genitourinary malformations, single nostril, facial cleft, spina bifida, hypoplastic lungs, club foot and single umbilical artery. No single causative agent for this group was identified. A brief review of the literature is included regarding categorization of these malformations and also a discussion of the embryological basis for these lesions and possible etiological factors.