Fat-like Lesion(s), General



Fat-like Lesion(s), General


Sheri L. Harder, MD



DIFFERENTIAL DIAGNOSIS


Common



  • Choroid Plexus Xanthogranuloma


  • Lipoma


  • Craniopharyngioma


  • Teratoma


  • Dermoid Cyst


  • Ossified Falx


Less Common



  • Asymmetric Marrow, Petrous Apex


  • Cholesterol Granuloma, Petrous Apex


Rare but Important



  • “White” Epidermoid Cyst


  • Meningioma, Lipomatous


  • Encephalocraniocutaneous Lipomatosis


  • Retained Pantopaque


ESSENTIAL INFORMATION


Key Differential Diagnosis Issues



  • Fat vs. cholesterol-containing lesion



    • Fat (lipoma, dermoid, teratoma)


    • Cholesterol (craniopharyngioma, xanthogranuloma, cholesterol granuloma)


  • Fat vs. mimic (lesions with short T1)


Helpful Clues for Common Diagnoses



  • Choroid Plexus Xanthogranuloma



    • Common (70% of autopsies)


    • Incidental MR finding


    • Older patient with bilateral choroid plexus cysts



      • Hypodense, Ca++ on NECT


      • Usually T1 hypointense


  • Lipoma



    • Subpial mass (-50 to 100 HU, short T1)


    • 50% interhemispheric ± agenesis CC


  • Craniopharyngioma



    • Cyst contains high cholesterol fluid


    • Variable signal on MR


  • Teratoma



    • Midline mass with Ca++, adipose tissue


  • Dermoid Cyst



    • ± Cisternal fat droplets


    • NECT: 20-40 HU ± Ca++


    • MR: Heterogeneously hyperintense


  • Ossified Falx



    • Osseous metaplasia, fatty marrow


Helpful Clues for Less Common Diagnoses



  • Asymmetric Marrow, Petrous Apex



    • Asymmetric aeration


    • Fatty marrow, no expansile change


  • Cholesterol Granuloma, Petrous Apex



    • Expansile PA mass


    • T1/T2 hyperintense


Helpful Clues for Rare Diagnoses

Tags:
Aug 7, 2016 | Posted by in NEUROLOGY | Comments Off on Fat-like Lesion(s), General

Full access? Get Clinical Tree
Get Clinical Tree app for offline access