Primary panhypopituitarism/Posterior pituitary ectopia (pituitary dwarfism)

History: 5-year-old girl with short stature, delayed dentition, delayed skeletal maturation, and endocrine abnormalities.

Findings: Midline bright signal is present in the region of the tuber cinereum or midline sagittal and coronal T1-weighted MR images. Also demonstrated is a small sella turcica, diminutive pituitary gland, and an atretic pituitary stalk.

http://radiopaedia.org/articles/ectopic-posterior-pituitary

Atretic definition, the congenital absence, or the pathological closure, of an opening, passage, or cavity. See more.

 

Discussion: Because the posterior pituitary bright spot is felt to be due to the inherent signal intensity of neurosecretory granules in the neurohypophysis, an ectopic bright spot may be found in any process that disrupts the transport of antidiuretic hormone from the hypothalamus to the posterior pituitary lobe. Primary panhypopituitarism occurs when the pituitary gland is congenitally hypoplastic or absent. In the clinical setting of panhypopituitarism, a high correlation exists between the hormonal disorder and ectopia of the neurohypophysis. Growth disturbances may predominate the clinical picture, as in the index case. A history of traumatic or breech delivery is present in many patients, with the presumed association being perinatal rupture of the pituitary infundibulum. Characteristic MR findings of primary panhypopituitarism include a small sella turcica, diminutive pituitary gland, atretic pituitary stalk, and an ectopic posterior pituitary bright spot.

The posterior pituitary (or neurohypophysis) is the posterior lobe of the pituitary gland which is part of the endocrine system. The posterior pituitary is not glandular as is the anterior pituitary.

sella turcica
a depression in the sphenoid bone, containing the pituitary gland.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s