Brain Flashcards
What is the ddx for bilateral globus pallidus T2/DWI hyperintensity?
CO poisoning Wilson disease Japanese encephalitis CJD Leigh syndrome
What is T1 bright on MR?
My best friend is pretty cool
M - melanin B - blood (subacute) from methemoglobin F - fat P - protein, paramagnetic substances (manganese, copper), posterior pituitary C - contrast
What are examples of intraventricular lesions?
Colloid cyst Meningioma Choroid Ependymoma Neurocytoma Metastases
What is the differential for cerebellopontine angle masses?
A - acoustic schwannoma
M - meningioma
E - ependymoma
N - neuropepithelial cyst (arachnoid/epidermoid)
Aneurysms - Vertebral, Basilar, PICA Lipoma Arachnoid cyst Choroid plexus papilloma Metastases
Which cranial nerves never have nerve sheath tumors and why?
Olfactory and optic nerve
White matter tracts from cerebrum and do not have nerve sheaths
What cranial nerves in order of frequency are affected by cranial nerve sheath tumors
Usually sensory nerves
Superior division of vestibular cochlear nerve
Trigeminal
Glossopharyngeal
Lower cranial nerves
Pure motor - Rare!
What regions of the brain are affected in herpes encephalitis?
Medial temporal lobes (uncus)
Cingulate gyrus of medial frontal and parietal lobes
Affects superficial gray matter
What cranial nerves originate from the midbrain?
CN 3 and 4
What cranial nerves originate from the pons?
CN 5, 6, 7, 8
What cranial nerves originate from the medulla?
CN 9, 10, 11, 12
DDX for CP angle tumours?
AMEN
acoustic schwannoma - called vestibular schwanomma
Meningioma
Ependymoma
Neuroepithelial cyst
What is T1 bright?
Fat Bone Marrow Methemoglobin Paramagnetic contrast Slow flow blood Radiation changes
What are findings of neurofibromatosis type 2?
M - multiple I - inherited S - schwanomas M - meningiomas E - ependymomas
What are the classic areas affected in carbon monoxide poisoning?
Globus palladi bilaterally
What are the 4 stages of neurocysticercosis?
- Vesicular - smooth thin-walled cyst (viable larvae)
- Colloidal vesicular - Hyperdense cyst fluid with edema (Degenerating larvae)
- Granular nodular - Mild edema (healing)
- Nodular calcified - small calcified nodule (healed)