CNS Tumors and Infections Part2

2. PITUITARY MICROADENOMA definition, measures less than 1 cm. 75% of these lesions cause hormonal abnormalities whereas the nonhormonally active lesions become symptomatic secondary to the size

\u2022By

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Clinical symptoms associated with pituitary adenomas can be visual disturbance and headaches. Pituitary adenomas can hormonal abnormalities.

produce

a

spectrum

of

Prolactin-producing adenomas are the most common, however, but growth hormone, ACGH, and gonadotrophic producing adenomas are also possible. Usually appears hypointense on T1 weighted images and has a variable appearance on the T2 weighted images. **Amenorrhea, prolactin

increased

enhancement with intermixed regions of increased and decreased signal. There is a central region of signal void consistent with calcification. There are cystic regions within high signal intensity on T1 weighted suggesting high protein contrast. There is obstructive hydrocephalus Craniopharyngiomas

serum

4. SCHWANNOMA \u2022

\u202260-90%

CN VIII and V origin most common,

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+/- encapsulated

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does

not \u2022

3. CRANIOPHARYNGIOMA \u2022 Present clinically with increased intracranial pressure, hypothalamic dysfunction, or chiasmatic compression symptoms \u2022

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Origin: cranio from pars tuberalis, Rathke\u2019s from pars intermedia Location: 70% intra and suprasellar, 10% suprasellar only, 10% intrasellar only

of CPA (Cerebello-pontine Angle) masses

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Pituitary Microadenoma Typically, enhance

8-10% of all intracranial neoplasms

Presenting weakness..

age

40-60

with

neuralgia,

masticator

Imaging

\

u

\

u

e

0

0

0

Hypo/iso on CT +/- Ca2+

e 0 0 0 Hypo or iso on T1, hyper T2\u2014most but may be cystic, necrotic, hemorrhagic

DDX FOR CEREBELLOPONTINE ANGLE MASS \u2022 Acoustic shwannomas, \u2022

Meningiomas

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Epidermoids

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Arachnoid cysts

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Aneurysms

**68 y.o. with left sided hearing loss

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Age peak: 5-10 and less so at 50-60

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Most common suprasellar mass in children (50%)

Demonstrate a left

\u2022Imaging:

80% Ca2+ in children 40% Ca2+ adults, 90% cystic, 90% rim enhance, hyper T1/T2 (cholesterol), +/optic tract signal abnormality **11

y.o. M with worsening headache

Heterogenous primarily cystic appearing mass within the suprasellar cistern is noted. These are focal regions of decreased signal intensity, which may be secondary to calcifications.

Craniopharyngioma There is extensive, primarily peripheral

cerebellopontine angle mass

Schwannoma