Tuber cinereum hamartomas are not true tumors, they are congenital malformations caused by normal neurons and glial cells from the tuber cinereum in an abnormal location. 

Clinically, they usually present by early precocious puberty and gelastic seizures; less commonly by developmental delay. There is no correlation between the clinical symptoms and the size of the hamartoma. 

On MR studies, the tuber cinereum hamartoma appears as a round suprasellar mass with variable size from a few millimeters to 5 cm in diameter. The signal is similar to that of grey matter on all sequences and no enhancement after gadolinium injection. MR spectroscopy can be normal or shows a slight decrease in N-acetyl aspartate and an increase in choline and myoinositol. Non-enhancing hypothalamic-chiasmatic glioma is the only differential diagnosis of hamartoma.