Rathke’s Cleft Cyst

Findings:

High T1 & T2 slightly expansile sellar lesion, displaces normal pituitary tissue.

Non-neoplastic remnants of Rathke’s pouch

Majority are asymptomatic, symptoms include visual defects, pit insufficiency, headaches.

Can be high or low T1 but always high T2.

DDs:
Arachnoid cyst
Epidermoid
Pituitray adenoma
craniopharyngioma.

Rathke’s Cleft Cyst
 
Nonneoplastic cyst arising from remnants of embryonic Rathke cleft.

Best diagnostic clue is nonenhancing, noncalcified intra/suprasellar cyst with intracystic nodule
Uncommon but pathognomonic = "posterior ledge sign", upward extension through diaphragma sellae with ledge of tissue overlying posterior lobe


40% completely intrasellari 60% suprasellar extension
Most RCCs are limited to sella, between anterior, intermediate lobes.
Most symptomatic RCCs are between 5-15 mm in diameter.