Causes of Pituitary Hyperplasia

The pituitary can enlarge physiologically under the following conditions:

• Hypothyroidism
• Pregnancy
• Lactation

Look for a sellar mass that is not separate from the pituitary. In contrast to pituitary adenoma, there is no remodeling of the sella. When in doubt, dynamic contrast-enhanced MRI can resolve the issue. Pituitary hyperplasia will enhance uniformly, while pituitary tumors will have an enhancement pattern different from the rest of the gland.