Acromegaly with normal pituitary MRI

Acromegaly is commonly caused by a growth hormone (GH) secreting pituitary adenoma, which is often evident on pituitary imaging by the time of presentation. Here we describe 4 patients with acromegaly who had normal MRI of the pituitary at the time of diagnosis. Contrast enhanced computer tomography (CECT) chest and abdomen were also normal. All 4 patients were females and aged 45, 53, 69 and 70 years. They had acromegaloid features of varying severity and duration. Dynamic magnetic resonance imaging (MRI) was performed in 3 patients, which revealed pituitary microadenomas in all 3 of them. This highlights the heterogenous behavior of GH secreting tumours and the value of dynamic MRI in visualizing microadenomas.