Normal pituitary stalk

The pituitary stalk, like the rest of the pituitary is largely outside the blood brain barrier and therefore normally enhances following the administration of gadolinium. It gradually tapers inferiorly, and superiorly is spread by the infundibular recess of the third ventricle.
There have been a number of studies looking at the range of normal sizes of the pituitary stalk. One study suggested that 95% of patients should have a stalk that measures no more than
- 4.4mm at the level of the optic chiasm, and
- 2.7mm just above the gland.
Abnormal nodular enhancement can be seen in tumours, infections, and cellular infiltrates (for more details on this DDx please visit Radiopaedia.org here)
References
1. L.A. Loevner “Brain Imaging - Case review”
2. Simmons G. et al “MR Imaging of the Pituitary Stalk” AJR:159, August 1992
Credit: Dr Frank Gaillard
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