Neurology Flashcards
Brain metastases
Metastatic brain cancer is the most common form of brain tumours. They are often multiple and not treatable with surgical intervention.
Tumours that most commonly spread to the brain include:
- > Breast
- > Lung
- > Bowel
- > Skin (namely melanoma)
- > Kidney
Glioblastoma multiforme
Glioblastoma is the most common primary tumour in adults and is associated with a poor prognosis (~ 1yr).
Imaging -> Solid tumours with central necrosis and a rim that enhances with contrast. Disruption of the blood-brain barrier and therefore are associated with vasogenic oedema.
Histology -> Pleomorphic tumour cells border necrotic areas
Treatment -> Surgical with postoperative chemotherapy and/or radiotherapy. Dexamethasone is used to treat the oedema
Meningioma
The second most common primary brain tumour in adults. Typically BENIGN, extrinsic tumours of the central nervous system. They arise from the dura mater of the meninges and cause symptoms by compression rather than invasion.
Location -> the falx cerebri, superior sagittal sinus, convexity or skull base.
Histology -> Spindle cells in concentric whorls and calcified psammoma bodies
Treatment -> Observation, radiotherapy or surgical resection.
Vestibular schwannoma
Benign tumour arising from the eighth cranial nerve (vestibulocochlear nerve).
Location -> Often seen in the cerebellopontine angle.
Presentation -> Hearing loss, facial nerve palsy (due to compression of the nearby facial nerve) and tinnitus.
Association -> Neurofibromatosis type 2
Histology -> Antoni A or B patterns are seen. Verocay bodies (acellular areas surrounded by nuclear palisades)
Treatment -> Observation, radiotherapy or surgery.
Pilocytic astrocytoma
The most common primary brain tumour in children
Histology -> Rosenthal fibres (corkscrew eosinophilic bundle)
Medulloblastoma
Aggressive paediatric brain tumour that arises within the infratentorial compartment. It spreads through the CSF system.
Histology -> Small, blue cells. Rosette pattern of cells with many mitotic figures
Treatment -> Surgical with and chemotherapy.
Ependymoma
Commonly seen in the 4th ventricle => may cause hydrocephalus
Histology -> Perivascular pseudorosettes
Oligodendroma
Benign, slow-growing tumour common in the frontal lobes
Histology -> Calcifications with ‘fried-egg’ appearance
Haemangioblastoma
Vascular tumour of the cerebellum
Associations -> Von Hippel-Lindau syndrome
Histology -> Foam cells and high vascularity
Pituitary adenoma
Benign tumours of the pituitary gland. Can be secretory (producing a hormone in excess) or non-secretory. Divided into microadenomas (smaller than 1cm) or macroadenoma (larger than 1cm).
Presentation -> hormone excess (e.g. Cushing’s due to ACTH, or acromegaly due to GH) or depletion. Compression of the optic chiasm will cause a bitemporal hemianopia due to the crossing nasal fibers.
Investigation -> pituitary blood profile and MRI.
Treatment -> hormonal or surgical (e.g. transphenoidal resection).
What visual field defect is associated with pituitary adenoma?
Bitemporal hemianopia. Upper affected more than lower.
Craniopharyngioma
Most common paediatric supratentorial tumour but can present in adults also.
Is a solid/cystic tumour of the sellar region that is derived from the remnants of Rathke’s pouch.
Presentation -> hormonal disturbance, symptoms of hydrocephalus or bitemporal hemianopia.
Histology -> Derived from remnants of Rathke pouch
Investigation -> pituitary blood profile and MRI.
Treatment -> surgical with or without postoperative radiotherapy.
What visual field defect is associated with craniopharyngioma?
Bitemporal hemianopia. Lower affected more than upper.
