DISCUSSION Congenital pituitary gland absence (aplasia) is a rare anomaly that may involve absence of both the anterior and the posterior pituitary lobes and, in many cases, the pituitary stalk Imaging findings Absence of an identifiable pituitary gland Small sella turcica Differential diagnosis: Severe hypoplasia of the pituitary gland Empty sella
CLINICAL PRESENTATION Global developmental delay Neonatal hypoglycemia Micropenis
MRI FINDINGS absence of an identifiable pituitary gland Small and flat sella turcica, sometimes covered by a layer of dura Absent / hypoplastic infundibular stalk Ectopic posterior pituitary
DISCUSSION Congenital pituitary gland absence (aplasia) is a rare anomaly that involves absence of both the anteriorand the posterior pituitary lobes and, in many cases, the pituitary stalk In patients with neonatal panhypopituitarism,severe symptoms of hypoglycemia may appear during the 1 st hours of life Other symptoms include Seizures Apnea Cardiovascular collapse and arrest Infants are of normal length and weight at term or postterm
Physical examination may be unrevealing; however, some male infants have a microphallus, a poorly developed scrotum, and/or small undescended testes The normal size of the infant at birth has been explained by the presence of maternal growth hormone Facial abnormalities—include, cleft lip and palate, poorly developed nasal septum, and hypotelorism
Although the size of infants is normal at birth, growth retardation and delayed bone age may be found at 6 – 8 weeks of age Neonatal hypoglycemia associated with poorly functioning anterior pituitary gland may represent a series of separate syndromes with no structural brain anomalies or with defects such as Craniofacial defects Absence of septum pellucidum Septo-optic dysplasia Arrhinencephaly, Holoprosencephaly Anencephaly
I MAGING FINDINGS Characteristic imaging finding of pituitary aplasia is absence of an identifiable pituitary gland Small and flat sella, may be covered by a layer of dura Absence of pituitary stalk, posterior pituitary Differential diagnosis 1. Severe hypoplasia of the pituitary gland Sella is empty but generally not flat Infundibulum and posterior pituitary are generally present 2. Empty sella Pituitary gland is severely flattened.
S AG AND CORONAL T 1 WEIGHTED IMAGES SHOWING ABSENCE OF ANTERIOR AND POSTERIOR PITUITARY
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