False pituitary tumor in CSF leaks.

The authors describe five patients with typical clinical and MRI features of CSF leak and large enhancing pituitaries. The source of CSF leak was identified and surgically repaired in three patients. This was followed by disappearance of clinical symptoms and resolution of MRI abnormalities, including the pituitary enlargement. Enhancing enlargement of pituitary is another head MRI abnormality in CSF leaks, likely reflecting a secondary pituitary hyperemia.