CNS pathology Flashcards
MC cause and type of head injury
Falls
Deacceleration injury
What is raccoon eye and Battle sign? What do they indicate respectively?
Raccoon eye: periorbital ecchymosis ==> anterior cranial fossa fracture
Battle sign: retromastoid ecchymosis ==> petrous temopral bone fracture
Glasgow Coma Scale (associated mortality)
= assessment of impaired consciousness level in response to defined stimuli to determinen severity of head injury
Eye opening response (4): spontaneous –> to speech –> to pain –> none
Verbal response (5): orientated –> confused –> inappropriate words –> incomprehensible sounds –> none
Motor response (6): obey commands –> localization to pain –> normal flexion to pain –> abnormal flexion to pain –> extension to pain –> none
> =14: minor severity (0.4%)
9~13: moderate severity (5%)
<=8: severe severity (45%)
Types of skull fractures (4)
Linear fracture
Depressed fracture
Basilar fracture
Diastatic fracture
Types of brain parenchymal injury
Contusion (coup or countercoup)
Laceration
Diffuse axonal injury
Types of brain traumatic vascular injury (which is MC?) (What are the vessels involved?)
Epidural haematoma: middle meningeal artery
Subdural haematoma (MC): bridging vein between dura & arachnoid membrane
Cerebral / contusional haematoma: intracerebral vessels
Difference in CT between epidual and subdural haematoma
lens-shaped, limited by suture lines
crescent-shaped, cross suture lines
Involvement of which spinal level will lead to respiratory compromise in spinal injury?
C4 or above
2 types of cerebral oedema and pathogenesis
vasogenic oedema: malignancy / infection –> BBB diruption & ↑ vascular permeability
cytotoxic oedema: generalised hypoxia / ischaemic insult –> neuronal / glial cell injury –> cellular swelling
Cushing triad
sinus bradycardia, hypertension, irregular breathing
==> ↑ ICP
Signs of ↑ ICP
papilledema
headache, projectile vomiting without nausea
Cushing triad
4 types of herniation (herniated structure)
- Subfalcine (cingulate gyrus)
- Uncal (uncus)
- Central (bilateral uncus)
- Tonsilar (cerebellar tonsils)
Results of uncal herniation
[CN3] ipsilateral pupil dilation
[cerebral peduncle] hemiplegia
[midbrain] coma
Results of tonsillar herniation
[medulla] respiratory arrest, BP instability
[cerebellum] cerebellar signs
Brain tumours predominantly found in children (3)
pilocytic astrocytoma
ependymoma
medulloblastoma
Benign brain tumours (3)
pilocytic astrocytoma
meningioma
Schwannoma
What are the brain tumours?
Glioma
1. Glioblastoma multiforme
2. Diffuse astrocytoma
3. Pilocytic astrocytoma
4. Oligodendroglioma
5. Ependymoma
Extra-axial tumours
1. Meningioma
2. Schwannoma
3. Pituitary adenoma
Other primary tumours
1. Medulloblastoma
2. Primary CNS lymphoma
3. CNS germinoma
Metastasis
1. Cerebral
2. Leptomeningeal
MC brain tumour in adult (what is the origin)
Glioblastoma multiforme
(astrocytes)
Common site and the respective gross pathology of glioblastoma
Corpus callosum (butterfly lesion)
Pathology of glioblastoma multiforme (4)
necrosis, endothelial proliferation, markedly pleomorphic cells, contrast ring-enhancement in CT/MRI
Median survival of glioblastoma multiforme with treatment
15 months
MC spinal cord tumour
Ependymoma
Site of medulloblastoma
vermis of cerebellum
Common site of CNS germinoma
pineal gland
MC sources of brain metastasis (3)
lungs, breasts (long latent period), colorectal
Brain tumour with diffuse infiltration, fibrillary matrix, and thus incurable by surgery
Diffuse astrocytoma
Brain tumour with cystic lesion, with mural nodule and spindle cells
Pilocytic astrocytoma
Brain tumour with calcifications, clear vacuolated cells (fry egg cell), branching vessels
Oligodendroglioma
Brain tumour with whorls, psammoma, calcifications
Meningioma
Brain tumour with rosettes
Medulloblastoma
What is lacunar infarct?
small infarcts (<15mm) at deep grey / white matter of the brain
Causes of global ischaemia of the brain (Which area is the most vulnerable?)
circulatory collapse, severe hypoglycaemia, epilepsy
(Hippocampus)
Pathology of brain ischaemia
Gross: acute swelling +/- herniation –> liquefactive necrosis
Microscopy:
[early] red neurons, acute inflammation (neutrophils, oedema), shrinking & karyolysis of neurons
[late] microglial cells with haemosiderin, liquefaction, glial fibres
MC site and MC cause of cerebral haemorrhage
basal ganglia
hypertension
MC cause of lobar haemorrhage (which disease is it associated with?)
cerebral amyloid angiopathy
Alzheimer’s disease
Causes of Berry aneurysm
hypertension, connective tissue disease, structural defects
Sites of Berry aneurysm (4)
Anterior communicating artery (MC)
MCA bifurcation
Terminal ICA
Basilar artery bifurcation
Risk factors for sporadic type of Alzheimer’s disease
age
multiple trauma
DM
apoE4
Genes for familial early-onset type of Alzheimer’s disease
APP on chromosome 21 (related to Down’s syndrome)
PS1, PS2
MC site of pathology in Alzheimer’s disease
hippocampus
Pathogenesis of Alzheimer’s disease
- abnormal cleavage of amyloid precusor protein (APP) –> polymerisation of Aβ42 peptides –> large aggregates (neuritic plaque)
- hyperphosphorylation of tau protein –> tangle formation (neurofibrillary tangles)
Which protein is involved in the neuronal inclusions in
a. Parkinson’s disease?
b. Fronto-temporal dementia (FTD)?
a. lewy bodies, tau
b. TDP-43, tau
Which dementia presents with behaviour and language preceding memory loss?
fronto-temporal dementia (FTD)
Creutzfeldt-Jakob disease
Prion disease
Which disease is related to Gower’s sign, calf pseudohypertrophy, cardiomyopathy? (heritance)
Duchenne / Becker muscular dystrophy (X-linked)
Floppy baby syndrome is the infantile presentation of which disease?
Spinal muscular atrophy
Histology is only useful in which two endocrine cancers to determine malignancy?
papillary thyroid carcinoma, neuroblastoma
1st and 2nd MC pituitary adenoma
Prolactinoma, Null cell adenoma
Size limit in pituitary adenoma to differentiate between macroadenoma and microadenoma
1cm
Pathology of pituitary adenoma (4)
- foci of haemorrhage
- cellular monomorphism
- lack of reticulin network
- may infiltrate adjacent bone, dura
Aetiology of goitre (4)
- TSH (e.g. iodine deficiency)
- Graves’ disease
- Thyroiditis
- Neoplasm
Post-thyroidectomy monitoring (3)
- Neck USG
- TSH & thyroglobulin
Pathogenesis of Hashimoto’s thyroiditis (2)
anti-TSH-R Ab
CD8+ T cells mediate killing
Genetic association with Hashimoto’s thyroiditis
HLA-DR3, DR5
Pathology of Hashimoto’s thyroiditis (3)
- atrophic thyroid follicles
- infiltration of lymphocytes & plasma cells
- abundant Hurthle cells
Genetic association of Graves’ disease
HLA-DR3
Pathology of Graves’ disease (2+2)
[thyroid] diffuse hyperplasia of thyroid epithelium, T-cell infiltration
[orbital tissue / skin] T-cell infiltration, ↑ ECM components
MC thyroid carcinoma
Papillary thyroid carcinoma
Which thyroid carcinoma orginates from para-follicular C cells?
Medullary thyroid carcinoma
Which thyroid carcinoma spread via blood only?
Follicular thyroid carcinoma
Genes for papillary thyroid carcinoma (3)
BRAF, RET, RAS
Gene for follicular thyroid carcinoma
PAX8/PPARγ1 fusion
Gene for anaplastic thyroid carcinoma
TP53
Gene for medullary thyroid carcinoma
RET [MENII]
Which thyroid carcinoma has very poor prognosis?
anaplastic thyroid carcinoma
Pathology of papillary thyroid carcinoma (6)
- multi-focal, non-encapsulated
- Nuclear size and shape: nuclear enlargement, elongation, overlapping
- Chromatin: Ophan Annie nucleus
- Nuclear membrane: irregular contour, nuclear groove, nuclear pseudoinclusion
- Architecture: papillary / follicular
- Others: Psammoma bodies
Pathology of follicular thyroid carcinoma
focal, encapsulated (cannot be distinguished from follicular adenoma without signs of invasion)
Pathology of anaplastic thyroid carcinoma
small blue round cells
Pathology of medullary thyroid carcinoma
amyloid deposits
Triple assessment for thyroid gland
TFT, USG, FNAC
Framework for follow-up of thyroid nodule
Bethesda system
Sources of metastatic thyroid cancer (2)
RCC, breast
MC endocrine disorder in adult
Hyperparathyroidism
Familial syndrome associating with parathyroid hyperplasia
MEN1, MEN2a
Genes (2) associated with hyperparathyroidism
PRAD1, MEN1
What is pseudohypoparathyroidism?
(AD) PTH resistance
Pathology of adrenal cortex in exogenous cushing syndrome
adrenal atrophy sparing zona glomerulosa
Pathology of adrenal cortex in Cushing disease
bilateral adrenal hyperplasia, yellow thick cortex
Which is the “10% tumour”? Explain (4)
Phaeochromocytoma. 10% bilateral, extra-adrenal, malignant, secrete adrenaline/ dopamine
Familial syndrome related to phaeochromocytoma
MENII, von Hippel-Lindau syndrome, NF1
Pathology of phaeochromocytoma (2)
Zellballen pattern, rich vascularity
What is the only criteria of malignancy for phaeochromocytoma?
Distant metastasis
Pathology of neuroblastoma
SBRCT
MEN1 syndrome (gene, 3 associated tumours)
MEN1, parathyoid, pancreas, pituitary
MEN2A syndrome (gene, 3 associated tumours)
RET, MTC, adrenal medulla, parathyroid
MEN2B syndrome (gene, 3 associated tumours)
RET, medullary thyroid carcinoma, adrenal medulla, extra-endocrine
MC SOL in head injury
Subdural haematoma
Autopsy findings in ↑ ICP (6)
flattened gyri, narrowed sulci
midline shift
obliterated ventricles
herniation, commpression of brainstem
cerebral ischaemia
cerebral oedema
Types of intracranial haemorrhage
Epidural haematoma
Subdural haematoma
Subarachnoid haemorrhage
Cerebral haemorrhage
Which intracranial haemorrhage is assoicated with lucid interval (~1 hour)?
Epidural haemorrhage
What is leukoaraiosis? Which disease does it imply? How does it present on imaging?
demyelination of white matter, esp. in the periventricular region
Binswanger disease (subcortical ischaemic vascular dementia)
periventricular radiolucency
What is neuritic plaque and neurofibrillary tangles? How to stain them (2)?
Extracellular amyloid core, surrounded by neurites (irregular twisted axons)
Intracellular tau-containing filaments
IHC or silver stain