FIG 3. Case 17, group A. Images in a 74 year-old-woman with a growth hormone–secreting adenoma show HSI (arrow).

A, Coronal section 6 months after surgery. Postoperatively, the adenoma was debulked, and the HSI was below the chiasm and deviated to the left. It was continuous with the proximal portion of the pituitary stalk.

B, Coronal section before surgery. Preoperatively, an ovoid HSI is visible on the supradiaphragmatic level on the left side. The optic chiasm is compressed superiorly.