Objective: Excessive weight gain frequently occurs in patients with hypothalamic tumors and lesions leading to hypothalamic obesity (HO).
Methods: Digital brain magnetic resonance imaging (MRI) and clinical outcomes were studied retrospectively in a single center, including 45 children with postoperative lesions in the sellar region (41 craniopharyngiomas, 4 with Rathke's cleft cysts), ∼5 years post-surgery, mean age 13.9 years. Four standard sections covering hypothalamic areas critical to energy homeostasis were used to assess lesions and calculate a hypothalamic lesion score (HLS); the association with HO was examined.
Results: Compared to subjects who did not develop HO (n = 23), subjects with HO (n = 22) showed more frequently lesions affecting the third ventricular floor, mammillary bodies, and anterior, medial (all P < 0.05), and most importantly posterior hypothalamus (P < 0.01). The HLS correlated significantly with BMI z-score changes 12 and 30 months post-surgery, even after adjusting for potential confounders of gender, age at surgery, surgery date, surgery BMI z-score, hydrocephalus, and residual hypothalamic tumor (r = 0.34, P = 0.03; r = 0.40, P = 0.02, respectively). Diabetes insipidus was found to be an endocrine marker for HO risk.
Conclusions: The extent of damage following surgery in the sellar region can be assessed by MRI using a novel scoring system for early HO risk assessment.
© 2015 The Obesity Society.