Regarding hypothalamic lesions,
1. Craniopharyngioma are typically predominantly cystic in adults
2. Hypothalamic germinomas typically involve base of the infundibular stalk
3. Hypothalamic hamartomas usually show no change in size on long term follow-up
4. Hypothalamic-chiasmatic gliomas are strongly associated with NF-1
5. Dynamic MRI is helpful in differentiating LCH from germinoma
Answers: F, T, T, T, F
Notes:
Craniopharyngiomas (CP) have a bomodal presentation; the paediatric CPs are typically solid and cystic (adamantinomous type) and the adult CPs are perdominantly solid (papillary).
Hypothalamic germinomas present in childhood and teens; synchronous lesions in pineal region are seen in 10%; typically seen in the base of the infundibular stalk and show homogenous contrast enhancement.
Hypothalamic hamartomas usually present by 10-20 years, boys being more commonly affected; present with precoucious puberty or gelastic seizures; sesille ot pedunculated isointense lesionsin tuber cinerium; do not change in size and signal at long term follow-up.
Hypothalamic-chiasmatic gliomas are paediatric tumors (2-4 years) and up to 50% have a family history of NF-1.
On dynamic MRI, germinomas, LCH and hemangioblastomas show gradual increase in enhencement without washout; adenohypophysitis showssharp increase in curve with steep washout.
Reference:
Saleem SN et al. Lesions of the Hypothalamus: MR Imaging Diagnostic Features. RadioGraphics 2007;27:1087-1108
