Neuropathology Flashcards
Histology of Neural Tissues
- Neurons:
- Nuclei or ganglia (e.g. basal ganglia)
- Columns or layers (e.g. cortex)
- Glia:
- Structural and metabolic functions
- A… (metabolism)
- O… (structure)
- E… (lining of fluid compartments)
- M… (monocyte-lineage population)
- Meninges
- Blood vessels
- Neurons:
- Nuclei or ganglia (e.g. basal ganglia)
- Columns or layers (e.g. cortex)
- Glia:
- Structural and metabolic functions
- Astrocytes (metabolism)
- Oligodendrocytes (structure)
- Ependyma (lining of fluid compartments)
- Microglia (monocyte-lineage population)
- Meninges
- Blood vessels
Histology of Neural Tissues
- Neurons:
- Nuclei or … (e.g. basal ganglia)
- … or layers (e.g. cortex)
- Glia:
- Structural and metabolic functions
- Astrocytes (metabolism)
- Oligodendrocytes (structure)
- Ependyma (lining of fluid compartments)
- Microglia (monocyte-lineage population)
- M…
- Blood …
- Neurons:
- Nuclei or ganglia (e.g. basal ganglia)
- Columns or layers (e.g. cortex)
- Glia:
- Structural and metabolic functions
- Astrocytes (metabolism)
- Oligodendrocytes (structure)
- Ependyma (lining of fluid compartments)
- Microglia (monocyte-lineage population)
- Meninges
- Blood vessels
Histology of neural tissues:


Meninges
- Meninges - covering layers
- Provide … - interface between compartments
- … mater - covers entire brain and spinal column
- … - BV run within
- … mater - directly on surface of brain
- Meninges - covering layers
- Provide protection - interface between compartments
- Dura mater - covers entire brain and spinal column
- Arachnoid - BV run within
- Pia mater - directly on surface of brain

CEREBROSPINAL FLUID
- Normal volume 150ml
- Production by … plexus in the … ventricles (450ml per 24h)
- Resorption by arachnoid … in the subarachnoid space
- Metabolic importance
- … of the CNS
- Role in … regulation and defense
- Cerebral … of blood flow
- Normal volume 150ml
- Production by choroid plexus in the lateral ventricles (450ml per 24h)
- Resorption by arachnoid granulations in the subarachnoid space
- Metabolic importance
- Cushioning of the CNS
- Role in immune regulation and defense
- Cerebral autoregulation of blood flow
CEREBROSPINAL FLUID
- Normal volume …ml
- Production by choroid … in the lateral … (450ml per 24h)
- Resorption by arachnoid … in the … space
- … importance
- Cushioning of the CNS
- Role in immune regulation and defense
- Cerebral autoregulation of blood flow
- Normal volume 150ml
- Production by choroid plexus in the lateral ventricles (450ml per 24h)
- Resorption by arachnoid granulations in the subarachnoid space
- Metabolic importance
- Cushioning of the CNS
- Role in immune regulation and defense
- Cerebral autoregulation of blood flow
CSF CIRCULATION - VENTRICLES

- Blue space- ventricles
- Main compartment where CSF is located

CSF Circulation:
- Brain is completely surrounded by CSF and has … within it filled with CSF
- … … sinus - reabsorption back into venous system
- Constant …
- Brain is completely surrounded by CSF and has ventricles within it filled with CSF
- Superior sagittal sinus - reabsorption back into venous system
- Constant circulation

Hydrocephalus
- … to CSF flow
- Impaired resorption at arachnoid …
- … of brain tissue (e.g. dementias) = ex vacuo
- Very rarely …
- Obstruction to CSF flow
- Impaired resorption at arachnoid granulations
- Shrinking of brain tissue (e.g. dementias) = ex vacuo
- Very rarely overproduction

Types of hydrocephalus
- Types:
- Communicating
- Non-communicating
Raised intracranial pressure
- Mean CSF pressure above 200mm H20
- Increased CSF volume (…)
- How?
- Intracranial … occupying lesion (neoplasm, haemorrhage, abscess)
- Cerebral …
- Mean CSF pressure above 200mm H20
- Increased CSF volume (hydrocephalus)
- How?
- Intracranial space occupying lesion (neoplasm, haemorrhage, abscess)
- Cerebral oedema
Consequences of raised intracranial pressure - Herniation
- Sub… (cingulate)
- …/transtentorial
- …/cerebellar
- …/Cerebellar herniation may cause compression of the medulla with impairment of vital respiratory and cardiac functions
- Subfalcial (cingulate)
- Central/transtentorial
-
Tonsillar/cerebellar
- Tonsillar/Cerebellar herniation may cause compression of the medulla with impairment of vital respiratory and cardiac functions

Tonsillar/Cerebellar herniation may cause compression of the … with impairment of vital respiratory and cardiac functions
- Tonsillar/Cerebellar herniation may cause compression of the medulla with impairment of vital respiratory and cardiac functions
A brain …, or cerebral …, occurs when brain tissue, blood, and cerebrospinal fluid (CSF) shifts from their normal position inside the skull.
A brain herniation, or cerebral herniation, occurs when brain tissue, blood, and cerebrospinal fluid (CSF) shifts from their normal position inside the skull.
Tonsillar herniation at autopsy
- Coning herniation and compression of the … …
- Duret haemorrhages

- Coning herniation and compression of the medulla oblongata
- Duret haemorrhages
What type of herniation?

TONSILLAR HERNIATION

Space occupying lesion
- …/epidural haemorrhage
- … haemorrhage
- … haemorrhage
- Intracerebral haemorrhage
- Ischaemic infarct with subsequent oedema or haemorrhage
- Neoplasm
- Abscess
- Extradural/epidural haemorrhage
- Subdural haemorrhage
- Subarachnoid haemorrhage
- Intracerebral haemorrhage
- Ischaemic infarct with subsequent oedema or haemorrhage
- Neoplasm
- Abscess
Space occupying lesion
- Extradural/… haemorrhage
- Subdural haemorrhage
- Subarachnoid haemorrhage
- … haemorrhage
- … infarct with subsequent oedema or haemorrhage
- Neo…
- Ab…
- Extradural/epidural haemorrhage
- Subdural haemorrhage
- Subarachnoid haemorrhage
- Intracerebral haemorrhage
- Ischaemic infarct with subsequent oedema or haemorrhage
- Neoplasm
- Abscess
Head Trauma
- Skull fracture
- Parenchymal injury:
- … (bruising) concussion is a clinical term/syndrome
- … (penetration or tearing)
- Diffuse … injury
- Coup and …
- Important - clue to how injury has occurred
- After trauma, 2 areas of contusion in brain (one at front, one at back)
- Skull fracture
-
Parenchymal injury:
- Contusion (bruising) concussion is a clinical term/syndrome
- Laceration (penetration or tearing)
- Diffuse axonal injury
-
Coup and contrecoup
- Important - clue to how injury has occurred
- After trauma, 2 areas of contusion in brain (one at front, one at back)

… Only occur if brain moving hits a stationary object
Contrecoup Only occur if brain moving hits a stationary object

… injury is associated with a moving object impacting a stationary head
Coup injury is associated with a moving object impacting a stationary head

Coup vs Contrecoup
- COUP
- Head hits … object (wall) first - contusion at front (coup) then…
- CONTRECOUP
- Brain … within skull - rebound - brain rebounds back within skull to other side (… to force)
- Second injury caused (contrecoup injury)
- COUP
- Head hits stationary object (wall) first - contusion at front (coup) then…
- CONTRECOUP
- Brain moves within skull - rebound - brain rebounds back within skull to other side (opposite to force)
- Second injury caused (contrecoup injury)

Vascular injury- ….. rupturing
Vascular injury- BV rupturing
Vascular injury
- … - severe trauma with arterial laceration (middle meningeal artery)
- … - trauma may be minor in atrophy (bridging veins)
- Subarachnoid - rupture of saccular (berry) aneurysm (Circle of willis)
- Intracerebral - ….tension
- Extradural - severe trauma with arterial laceration (middle meningeal artery)
- Subdural - trauma may be minor in atrophy (bridging veins)
- Subarachnoid - rupture of saccular (berry) aneurysm (Circle of willis)
- Intracerebral - hypertension

Vascular injury
- Extradural - severe trauma with arterial laceration (… meningeal artery)
- Subdural - trauma may be minor in atrophy (… veins)
- … - rupture of saccular (berry) aneurysm (Circle of willis)
- … - hypertension
- Extradural - severe trauma with arterial laceration (middle meningeal artery)
- Subdural - trauma may be minor in atrophy (bridging veins)
- Subarachnoid - rupture of saccular (berry) aneurysm (Circle of willis)
- Intracerebral - hypertension

EXTRADURAL - SUBDURAL
- An extradural haematoma is a collection of blood in the ‘potential’ space between the skull and the outer protective lining that covers the brain (the … …).
- A subdural hematoma (SDH) is a type of bleeding in which a collection of blood—usually associated with a … brain injury—gathers between the inner layer of the … mater and the … mater of the meninges surrounding the brain.
- An extradural haematoma is a collection of blood in the ‘potential’ space between the skull and the outer protective lining that covers the brain (the dura mater).
- A subdural hematoma (SDH) is a type of bleeding in which a collection of blood—usually associated with a traumatic brain injury—gathers between the inner layer of the dura mater and the arachnoid mater of the meninges surrounding the brain.

SUBARACHNOID HAEMORRHAGE
- Arachnoid layer is relatively … - not easily visualised
- Most easily recognised at base of brain
- Confined to base of the brain
- … aneurysm - vascular abnormalities often seen in circle of willis
- … = subarachnoid haemorrhage

- Arachnoid layer is relatively thin - not easily visualised
- Most easily recognised at base of brain
- Confined to base of the brain
- Berry aneurysm - vascular abnormalities often seen in circle of willis
- Rupture = subarachnoid haemorrhage

INTRACEREBRAL HAEMORRHAGE
- … brain matter itself
- … associated
- Within brain matter itself
- Hypertension associated

Cerebral oedema
- … of brain matter
- … - increased vascular permeability
- … - neuronal, glial or endothelial cell damage
- Swelling of brain matter
- Vasogenic - increased vascular permeability
- Cytotoxic - neuronal, glial or endothelial cell damage
Cerebral infarction/Stroke
- 15% of cardiac output into brain
- …% of O2 demand in brain
- Stroke = … onset of neurological symptoms
- Hypoxia vs ischaemia (global vs focal)
- … are the most O2 sensitive cells
- … infarction in emboli (petechial lesions e.g. BM)
- … infarction in thrombosis
- Tolerate hypoxia better than ischaemia - lack of blood flow - damages neuronal tissue more than lack of oxygen
- 15% of cardiac output into brain
- 20% of O2 demand in brain
- Stroke = sudden onset of neurological symptoms
- Hypoxia vs ischaemia (global vs focal)
- Neurons are the most O2 sensitive cells
- Haemorrhagic infarction in emboli (petechial lesions e.g. BM)
- Ischaemic infarction in thrombosis
- Tolerate hypoxia better than ischaemia - lack of blood flow - damages neuronal tissue more than lack of oxygen

Cerebral infarction/Stroke
- …% of cardiac output into brain
- 20% of O2 demand in brain
- Stroke = sudden onset of neurological symptoms
- Hypoxia vs ischaemia (global vs focal)
- Neurons are the most O2 sensitive cells
- Haemorrhagic infarction in emboli (petechial lesions e.g. BM)
- Ischaemic infarction in …
- Tolerate … better than … - lack of blood flow - damages neuronal tissue more than lack of oxygen
- 15% of cardiac output into brain
- 20% of O2 demand in brain
- Stroke = sudden onset of neurological symptoms
- Hypoxia vs ischaemia (global vs focal)
- Neurons are the most O2 sensitive cells
- Haemorrhagic infarction in emboli (petechial lesions e.g. BM)
- Ischaemic infarction in thrombosis
- Tolerate hypoxia better than ischaemia - lack of blood flow - damages neuronal tissue more than lack of oxygen

Ischaemic infarct histology
- … neuronal injury
- ‘… neurons’
- Pyknosis of nucleus
- … of the cell body
- Loss of …
- Intense … of cytoplasm
- Owing to irreversible hypoxic/ischaemic insult
- Acute neuronal injury
- ‘red neurons’
- Pyknosis of nucleus
- Shrinkage of the cell body
- Loss of nucleoli
- Intense eosinophilia of cytoplasm
- Owing to irreversible hypoxic/ischaemic insult

What is this showing?

ischaemic infarct
What is this showing?

- Old ischaemic infarct
- Huge loss of tissue
- Healing artifact - scarring
Neoplasms
- Primary or metastatic?
- Approximately 75% … (hence 25% …)
- 20%of malignant childhood tumours are located in the …
- Gliomas (astrocytoma, oligodendroglioma, glioblastoma)
- …iomas
- Poorly differentiated neoplasms (medulloblastoma)
- Primary CNS …
- Meta… (lung, breast, skin/melanoma, kidney, GI tract)
- … nerve tumours (schwannoma, neurofibroma, MPNST)
- Primary or metastatic?
- Approximately 75% primary (hence 25% metastatic)
- 20%of malignant childhood tumours are located in the CNS
- Gliomas (astrocytoma, oligodendroglioma, glioblastoma)
- Meningiomas
- Poorly differentiated neoplasms (medulloblastoma)
- Primary CNS lymphoma
- Metastasis (lung, breast, skin/melanoma, kidney, GI tract)
- Peripheral nerve tumours (schwannoma, neurofibroma, MPNST)
Neoplasms
- Primary or metastatic?
- Approximately …% primary (hence …% metastatic)
- 20%of malignant … tumours are located in the CNS
- … (astrocytoma, oligodendroglioma, glioblastoma)
- Meningiomas
- … differentiated neoplasms (medulloblastoma)
- Primary CNS lymphoma
- Metastasis (lung, breast, skin/melanoma, kidney, GI tract)
- Peripheral … tumours (schwannoma, neurofibroma, MPNST)
- Primary or metastatic?
- Approximately 75% primary (hence 25% metastatic)
- 20%of malignant childhood tumours are located in the CNS
- Gliomas (astrocytoma, oligodendroglioma, glioblastoma)
- Meningiomas
- Poorly differentiated neoplasms (medulloblastoma)
- Primary CNS lymphoma
- Metastasis (lung, breast, skin/melanoma, kidney, GI tract)
- Peripheral nerve tumours (schwannoma, neurofibroma, MPNST)
- Top left - early … (…) increase in area, increase in areas of brain by tumour
- Top right - … - fast growing-haemorrhagic and necrotic
- Bottom left - …
- Bottom right - … - histologically

- Top left - early glioblastoma (oligodendroglioma) increase in area, increase in areas of brain by tumour
- Top right - glioblastoma - fast growing-haemorrhagic and necrotic
- Bottom left - meningioma
- Bottom right - meningioma - histologically

Infections - Neuropathology
- Meningitis - … of …
- Bacterial (acute or chronic)
- …
- …
- RMSV, neurosyphilis, lyme disease, malaria
- … - usually bacterial
- Encephalitis - viral (HSV, CMV, HIV, JC polyoma virus)
- Localised - toxoplasmosis, cysticercosis
- Meningitis - inflammation of meninges
- Bacterial (acute or chronic)
- Viral
- Fungal
- RMSV, neurosyphilis, lyme disease, malaria
- Abscess - usually bacterial
- Encephalitis - viral (HSV, CMV, HIV, JC polyoma virus)
- Localised - toxoplasmosis, cysticercosis

Infections - Neuropathology
- Meningitis - inflammation of meninges
- … (acute or chronic)
- Viral
- Fungal
- RMSV, neurosyphilis, … disease, malaria
- Abscess - usually …
- E… - viral (HSV, CMV, HIV, JC polyoma virus)
- Localised - toxoplasmosis, cysticercosis
- Meningitis - inflammation of meninges
- Bacterial (acute or chronic)
- Viral
- Fungal
- RMSV, neurosyphilis, lyme disease, malaria
- Abscess - usually bacterial
- Encephalitis - viral (HSV, CMV, HIV, JC polyoma virus)
- Localised - toxoplasmosis, cysticercosis

What is this image showing?


Toxoplasmosis
Toxoplasmosis is a common infection that you can catch from the poo of infected cats, or infected meat.

PROGRESSIVE / DEGENERATIVE CONDITIONS
- … diseases (Alzheimer d., Parkinson d.,)
- … degenerative diseases
- Accumulation of protein aggregates leading to loss of cellular and subsequent loss of CNS functions: Dementia, behavioural and personality changes, language disturbance, movement and coordination disturbance, paralysis.
- … diseases (multiple sclerosis)
- … diseases (Creutzfeldt-Jakob disease)
- … metabolic diseases (Neuronal storage diseases)
- Toxic & … metabolic diseases (Vit B1 & B12 def., CO toxicity, alcohol toxicity, radiation toxicity)
- Neurodegenerative diseases (Alzheimer d., Parkinson d.,)
- Spinocerebellar degenerative diseases
- Accumulation of protein aggregates leading to loss of cellular and subsequent loss of CNS functions: Dementia, behavioural and personality changes, language disturbance, movement and coordination disturbance, paralysis.
- Demyelinating diseases (multiple sclerosis)
- Prion diseases (Creutzfeldt-Jakob disease)
- Genetic metabolic diseases (Neuronal storage diseases)
- Toxic & acquired metabolic diseases (Vit B1 & B12 def., CO toxicity, alcohol toxicity, radiation toxicity)