Pediatric Ectopic Posterior Pituitary

Etiology: disruption of normal embryogenesis of the posterior pituitary
Imaging: ectopic bright spot in hypothalmus not in neurohypophysis, absent or small infundibulum
Clinical: short stature, diabetes insipidus

Radiology Cases of Ectopic Posterior Pituitary

MRI of ectopic posterior pituitary gland — Sagittal T1 MRI without (above) and with contrast (below) of the sella shows the high signal intensity posterior pituitary bright spot, which should be located posteriorly in the sella turcica, is instead located in the superior aspect of the pituitary stalk / inferior aspect of the hypothalamus. The pituitary gland is otherwise unremarkable.

MRI of pituitary interrupted stalk syndrome — Sagittal (above) and coronal (below) T1 MRI without contrast of the sella shows absence of the pituitary stalk between the sella and the hypothlamus. In addition, the high signal intensity posterior pituitary bright spot, which should be located posteriorly in the sella turcica, is instead located in the inferior aspect of the hypothalamus.