Temporal lesions

Arachnoid cyst: Intra-arachnoid CSF-filled sac that does not communicate with ventricular system. 50 – 60% located in middle cranial fossa. CT: CSF density, may expand, thin or remodel adjacent skullbone. MRI: Isointense with CSF on T1 and T2, as well as on FLAIR (compare epidermoid cyst with lack of signal suppression on FLAIR). No enhancement. ................
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