Hypothalamic lipoma associated with severe obesity. Report of 2 cases.

The association between hypothalamic dysfunction and obesity is well documented in both clinical and experimental models. The authors describe 2 children who developed obesity that could not be explained by endocrinological, genetic, or eating disorders. In both cases, cranial MR imaging revealed the typical appearance of a lipoma in the paramedian hypothalamus. In the absence of other etiologies, the authors hypothesized that in these 2 children obesity was caused by their hypothalamic lipomas. To the authors' knowledge, these are the first cases of hypothalamic lipomas likely to be causing obesity that have been described in children. These cases highlight the importance of performing cranial MR imaging in children with otherwise unexplained obesity.