| A rare midline cerebral malformation characterized by duplicated pituitary stalks and/or glands within duplicated sella. Patients may present various degrees of facial dysmorphism and endocrine abnormalities, including precocious puberty, hypogonadism, hypothyroidism and/or hyperprolactinemia, as well as associated congenital anomalies, such as clift lip/palate, bifid nasal bridge/tongue/uvula, hypothalamic enlargement with or without hamartoma, nasopharyngeal tumors, corpus callosum agenesis/hypoplasia, basilar artery duplication, and/or vertebral defects (in particular, duplication of the odontoid process). |