A pituitary gland squeezed upward by intrasellar kissing carotid arteries: Mimicking a pituitary microadenoma.

Background: Intrasellar kissing carotid arteries are a rare variant in which bilateral internal carotid arteries run very near each other at their cavernous sinus portion. We encountered a woman with the pituitary gland mimicking a pituitary microadenoma because the pituitary gland was compressed bilaterally by intrasellar kissing carotid arteries.

Case description: A 61-year-old woman with a chronic headache underwent magnetic resonance imaging, which revealed a sellar mass measuring 10.2 mm in height, 8.2 mm in length, and 4.0 mm in width at the midintercarotid level. Blood levels of all pituitary and target-organ hormones were within normal range. The height and superior convex shape of the sellar mass suggested that it was a nonfunctioning microadenoma, which was monitored over the past 16 years. A recent three-dimensional reconstruction of magnetic resonance angiography clearly showed that the pituitary gland was squeezed upward, compressed bilaterally, and extended superiorly by intrasellar kissing carotid arteries.

Conclusion: The pituitary gland can be squeezed upward by intrasellar kissing carotid arteries and mimic pituitary tumor.