Cns Tumors And Infections Part2

2. PITUITARY MICROADENOMA

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

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

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Pituitary adenomas can hormonal abnormalities.

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Prolactin-producing adenomas are the most common, however, but growth hormone, ACGH, and gonadotrophic producing adenomas are also possible.

•

produce

a

spectrum

of

Usually appears hypointense on T1 weighted images and has a variable appearance on the T2 weighted images. **Amenorrhea, prolactin

increased

serum

Pituitary Microadenoma Typically, enhance

does

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

4. SCHWANNOMA •

8-10% of all intracranial neoplasms

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60-90% of CPA (Cerebello-pontine Angle) masses

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CN VIII and V origin most common,

•

+/- encapsulated

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Presenting age weakness..

•

Imaging

not

40-60

with

neuralgia,

masticator

 Hypo/iso on CT +/- Ca2+ 3. CRANIOPHARYNGIOMA • Present clinically with increased intracranial pressure, hypothalamic dysfunction, or chiasmatic compression symptoms •

Origin: cranio from pars tuberalis, Rathke’s from pars intermedia

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Location: 70% intra and suprasellar, 10% suprasellar only, 10% intrasellar only

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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%)

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



Hypo or iso on T1, hyper T2—most commonly solid but may be cystic, necrotic, hemorrhagic

DDX FOR CEREBELLOPONTINE ANGLE MASS • Acoustic shwannomas, • Meningiomas • Epidermoids • Arachnoid cysts • Aneurysms **68 y.o. with left sided hearing loss

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

Demonstrate a left

cerebellopontine angle mass

Schwannoma