Computed tomographic demonstration of the posterior pituitary

Area of Science:

• Radiology
• Neuroimaging
• Endocrinology

Background:

• The sellar region, housing the pituitary gland, is complex.
• Accurate visualization of pituitary lobes is essential for diagnosing pathologies.

Purpose of the Study:

• To describe the typical CT imaging features of the posterior pituitary lobe.
• To aid in differentiating normal posterior pituitary anatomy from pituitary microadenomas.

Main Methods:

• Analysis of 700 axial, contrast-enhanced CT scans of the sellar region.
• Exclusion of empty sellae and pituitary lesions >8 mm.
• Detailed examination of 320 eligible CT scans for posterior pituitary lobe characteristics.

Main Results:

• The posterior pituitary lobe was identified in 39% of scans (124/320).
• It appeared as a 3-4 mm thick oval lucency, located anterior to the dorsum sellae.
• A normally convex anterior border can be compressed by anterior lobe microadenomas.

Conclusions:

• The normal posterior pituitary lobe has distinct imaging characteristics on contrast-enhanced CT.
• Understanding these features is vital to avoid misinterpreting normal anatomy as a posterior microadenoma.