T1 pre-gad | T1 post-gad | T1 post-gad with fat sat |
The general diagnosis of suprasellar lesions with increased T1 signal pre-gad includes craniopharyngioma, Rathke cleft cyst, hemorrhage, dermoid & lipoma, and ectopic posterior pituitary. Interruption of transport of hormones from the hypothalamus due to such entities as trauma, sarcoidosis or Langerhans cell histiocytosis may also produce a focus of increased T1 signal in the suprasellar region which may mimic these other entities. In this case the differential is limited due to the fact that the lesion is stable over time, mildly enhances and does not contain fat. In addition, the presence of a hypoplastic or absent sella suggests the diagnosis of an ectopic posterior pituitary gland. Related Cases
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Histiocytosis | Craniopharyngioma | Dermoid |