|
| Name | Location | Epithelium | Gross Pathology | CT | MR |
| Epidermoid | CPA >> middle fossa | Squamous only | Dry flaky waxy lamellar keratin, pearly | Homogeneous water-like attenuation | Lamellar, do not suppress on FLAIR or DWI |
| Dermoid | Retroclival suprasellar | Squamous, hair follicles, sebaceous gland, sweat glands | Mixture of hair, sebaceous grummus, buttery or cheesy | Fluid-fluid level, lipid top layer, hair-ball | Lipid layer bright on T1W |
| Colloid | Ant. 3rd ventricle | Ciliated Cuboidal, low columnar, Goblet cells | Gelatinous, hyaline | Round sharply demarcated, some hyperdense | Round sharply demarcated some bright on T1W, some bright on T2W, some with "black hole" on T2W |
| Arachnoid
|
Middle fossa | Arachnoid | CSF | CSF Isodense | CSF Isointense FLAIR - Dark DWI - Dark |
| Rathke Cleft | Intrasellar,
Suprasellar,
Behind pituitary stalk |
Ciliated Cuboidal - Columnar, Goblet cells | Water like | Bright on T1W and dark on T2W Rim enhancement in residual pituitary | |
| Craniopharyngioma - child | Suprasellar above and anterior to stalk | Squamous (stratified and palisading) and adamantinomatous tissue w/connective tissue rim and reactive astrogliosis | Wet nodular keratin, "machine oil" with cholesterol | Ca++, mixed cystic and solid, solid enhances | May be bright on T1W, solid regions enhance |
| Craniopharyngioma - adult | Suprasellar above and anterior to stalk | Squamous (sheets, no palisading) and forming (pseudo) papillary structures | Solid masses without cholesterol, no wet keratin, no Ca++ | Solid mass | Solid regions enhance |
Modified from Smirniotopoulos, JG: "Extraaxial Neoplasms of the CNS", RSNA 2000 Categorical Course
* Data compiled from [41,45-49]
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46. Sumida M, Uozumi T, Mukada K, Arita K, Kurisu K, Eguchi K. Rathke cleft cysts: correlation of enhanced MR and surgical findings. AJNR Am J Neuroradiol 1994; 15:525-532.
47. Kleinschmidt-DeMasters BK, Lillehei KO, Stears JC. The pathologic, surgical, and MR spectrum of Rathke cleft cysts. Surg Neurol 1995; 44:19-26; discussion 26-7.
48. Naylor MF, Scheithauer BW, Forbes GS, Tomlinson FH, Young WF. Rathke cleft cyst: CT, MR, and pathology of 23 cases [published erratum appears in J Comput Assist Tomogr 1996 Jan-Feb;20(1):171]. J Comput Assist Tomogr 1995; 19:853-859.
49. Sartoretti-Schefer
S, Wichmann W, Aguzzi A, Valavanis A. MR differentiation of adamantinous
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18:77-87.