1. #3. Recognize specific syndromes; extra-axial (cerebellopontine, pituitary, frontal) and intra-axial in brain tumor presentation

2. Extra-axial Tumors Extrinsic to the brain
include meningiomas, schwannomas, neurofibromas, and pituitary tumors, craniopharyngiomas as well as mesenchymal tumors of the skull, spine, and dura mater

3. Meningioma Derived from arachnoid cap cells of the arachnoid mater
Appear to arise from the dura mater grossly and on MRI: “dural based tumors”
Most common intracranial locations: along the falx cerebri , the convexities and the sphenoid wing.
Less common locations: foramen magnum, olfactory groove, and inside the lateral ventricle

4. Meningioma Mostly slow growing, encapsulated, and benign
Malignant  may invade adjacent bone or into the cortex
Previous cranial irradiation: risk
Tx: Total resection, post op radiation (atypical and malignant melanoma)

5. Postcontrast T1-weighted coronal MRI demonstrating a brightly enhancing lesion arising from the falx cerebri with moderate edema and mass effect on the right lateral ventricle. This is a falcine meningioma. Note also the small separate meningioma arising from the dura over the cerebral convexity.

6. Vestibular Schwannoma (Acoustic Neuroma)
Arise from the superior half of the vestibular portion of the vestibulocochlear nerve (CN VIII)
commonly present with progressive hearing loss, tinnitus, or balance difficulty
Large tumors may cause brain stem compression and obstructive hydrocephalus
Bilateral acoustic neuromas are pathognomonic for neurofibromatosis type 2, a syndrome resulting from chromosome 22 mutation.

7. Vestibular Schwannoma (Acoustic Neuroma)
Tx: microsurgical resection or with conformal stereotactic radiosurgery (gamma knife or linear accelerator technology)
Complication: damage to the facial nerve (cranial nerve VII)

8. A. Postcontrast T1-weighted axial MRI demonstrating a brightly enhancing mass on the right vestibular nerve with an enhancing tail going into the internal auditory canal (arrowhead). Pathology demonstrated vestibular schwannoma

9. Pituitary Adenoma
arise from the anterior pituitary gland (the adenohypophysis).
Microadenoma: <1cm; Macroadenoma >1 cm
Functional (i.e., secrete endocrinologically active compounds at pathologic levels) or nonfunctional (i.e., secrete nothing or inactive compounds).
The most common endocrine syndromes are Cushing's disease due to adrenocorticotropic hormone (ACTH) secretion, Forbes-Albright syndrome due to prolactin secretion, and acromegaly due to growth hormone secretion.

10. Pituitary Adenoma
Nonfunctional tumors commonly present when larger due to mass effect.
Common symptoms : visual field deficits due to compression of the optic chiasm, or panhypopituitarism due to compression of the gland.
Tx: Surgery (Transphenoidal), medical (Prolactinomas)

11. Postcontrast T1-weighted sagittal MRI demonstrating a large sellar/suprasellar lesion involving the third ventricle superiorly, and abutting the midbrain and pons posteriorly. The patient presented with progressive visual field and acuity loss. Pathology and lab work revealed a nonfunctioning pituitary adenoma.

12. Hemangioblastoma occur almost exclusively in the posterior fossa.
Twenty percent occur in patients with von Hippel-Lindau (VHL) disease, a multisystem neoplastic disorder
Appears as cystic tumors with an enhancing tumor on the cyst wall known as the mural nodule.
Surgical resection is curative for sporadic (non-VHL associated) tumors.

13. Craniopharyngioma
Benign cystic lesions that occur most frequently in children.
Second peak of occurrence around 50 years of age.
Symptoms result from compression of adjacent structures, especially the optic chiasm, pituitary or hypothalamic dysfunction or hydrocephalus may develop.
Treatment is primarily surgical
Complications: Visual loss, pituitary endocrine hypofunction, diabetes insipidus, and cognitive impairment from basal frontal injury

14. Neurofibroma
more fusiform and grow within the parent nerve, rather than forming an encapsulated mass off the nerve, as with schwannomas.
They are benign but not encapsulated.
They present similarly to schwannomas and the two may be difficult to differentiate on imaging.
Patients with multiple neurofibromas likely have neurofibromatosis type 1, also known as von Recklinghausen's neurofibromatosis.
Resection for symptomatic lesions should be offered.