Neuropath Exam Flashcards
Where is the amygdala?
Define Neurodegenerative Disease
Neurodegenerative diseases: progressive, irreversible
conditions that lead to neuronal loss – often caused by intra or
extracellular accumulation of a misfolded protein; usually
sporadic (less than 10% genetic); lead to dementia
Define Neuroinflammatory Disease
Neuroinflammatory diseases: conditions characterised by an
innate and/or adaptive inflammatory response – they can be
reversible or progressive / irreversible (multiple sclerosis is the
paradigm)
What is this and define it
Micrograph showing characteristic whorls (psammomas bodies sometimes inside).
Has NOT invaded the brain
- Meningioma
* A tumor originating from the meninges, the membranous layers surrounding the CNS. Meningiomas are the second most common primary neoplasm of the central nervous system, arising from the arachnoid “cap” cells of the arachnoid villi in the meninges. These tumors are usually benign in nature; however, they can be malignant.*
Meningiomas are usually rounded masses with well-defined dural bases that compress underlying brain but are easily separated from it.
They are most frequently attached to the dura over the superior parasagittal surface of frontal and parietal lobes, along the sphenoid ridge, in the olfactory grooves, the sylvian region, superior cerebellum along the falx cerebri, cerebellopontine angle, and the spinal cord. The tumor is usually gray, well-circumscribed, and takes on the form of space it occupies. They are usually dome-shaped, with the base lying on the dura.
What are the most common causes and treatment of Brain metastesis?
- Most common causes are lung cancer 48%, breast 15%, genitourinary tract 11%, osteosarcoma 10% and melanoma 9%. Head and neck cancers cause only 6%*
- Treatment is primarily palliative, aiming to reduce symptoms. Some patients can have aggressive therapy such as craniotomy with maximal excision, chemo, and radiosurgical intervention (gamma knife radiosurgery)*
What does this show?
3 metasteses in the cortex
Intraparenchymal metastases form sharply demarcated masses, often at the junction of gray and white matter, usually surrounded by a zone of edema. The boundary between tumour and brain parenchyma is well defined microscopically as well, although melanoma is one tumour that does not always follow this rule. Nodules of tumour, often with central areas of necrosis, are surrounded by reactive gliosis.
What is the septum pellucidum?
- Not to be confused with the medial septum, the SP is a thin, triangular, vertical membrane separating the anterior horns of the left and right lateral ventricles of the brain. It runs as a sheet from the corpus callosum down to the fornix.*
- Diffuse Axonal Injury*
- Rapid acceleration not contact
- Damage to white matter tracts
- Different density
Why are midline structures particularly susceptible to trauma?
Rigid and at the centre resulting in shearing or tearing force generated by rotational trauma as the two hemispheres shift move separately to one another.
What are the common sites for Berry aneuryms?
What are the different types of herniation?
What happens in uncle herniation?
Midline deviation, ridge on the uncus of the right temporal lobe indicates it’s herniated through the tentorial notch. Also the top of the right cerebellum has been squashed by the herniated lobe.
- What is the congenital abnormality in this brain?
- Agenesis of corpus callosum
- Can be partial or complete absence of the corpus callosum.*
- The fibres that would normally form the CC lie longitudinally (Probst Bundles)*
What is the pathology?
- Encephalocoele
Neural tube defect characterised by sac-like protrusions of the brain and the membranes that cover it through openings in the skull. The result is a groove down the midline of the upper part of the skull, or the area between the forehead and nose, or the back of the skull. When located in the back of the skull, encephaloceles are often associated with neurological problems
Originates from the occipital lobe
2 tissue types are involved, Scalp (connective) and neural tissue
- Where is the site of major atrophy in this brain?
- The brain also showed frontal lobe atrophy, what is the most likely diagnosis?
- Temporal lobes
- Picks
- What does Periventricular heterotopia do to a ventricle?
- What problem in development causes this?
- bumpy/lumpy surface instead of smooth It is caused by clumps of grey matter being located in the wrong part of the brain. It is characterized as a type of cortical dysplasia. May have one small node or even many nodes, and may occur in one or both sides.
- The problem is complete failure of migration from the germinal layer of ventricular zone that lines the neural tube to the desired region of the cortex by some differentiated neurons. Consequently many neurons remain in the ventricular zone as clumps or nodules whilst the remainder form the rest of the cortex.
Outline the Limbic system:
What is this? Which Limbic system tract is it affecting?
- Astrocytoma
- Fornix
What is this showing?
Major hydrocephalus, Large ventricles
- Parieto occipital area of brain of someone who died from resp failure following status epilepticus. What main region is damaged?
- What may have caused this?
- white matter
- White matter is more susceptible to hypoxic insult, rotational trauma from status epilepticus (DAI)
What pathology this showing?
What is the main abnormality in this brain?
- The apparent enlargement of the ventricles seen here is due to atrophy of the head of the caudate from neuronal loss with Huntington’s disease, an autosomal dominant condition characterized clinically by choreiform movements.
- caudate atrophy
Draw a sketch of the brain section and mark the area of the demyelinating plaque
Myelin stains darkly so lesions are white
little white circle in blue stain, just below cortex
Alzheimers (Microscopy)
- What are the main structures stained?
- What do they contain?
- What other structures can be seen?
- senile plaques
- Amyloid beta protein
- vessels (CAA) cerebral amyloid angiopathy
- What structures have been stained?
- What may have caused this damage?
- axons, the damaged white matter shows axonal swellings. These can occur anywhere but are particularly common in the parasagittal parts of the brain, the corpus callosum, fornix, internal capsule, and the brain stem.
- diffuse axonal injury due to head trauma
- What limbic structure is this?
- What are cell types stained?
- What is their function?
- Hippocampus
- Astrocytes
- Neurotransmitter metabolism, ion redistribution, glycogen storage, water storage.
- What specific anatomical region of the brainstem is this?
- What structure contains dopaminergic neurons?
- In which pathology is this affected?
- Midbrain
- Substantia Nigra
- Parkinson’s Disease
What does this show?
Spongiform change due to Prion Disease
the pathognomic finding is a spongiform transformation of the cerebral cortex, and often, deep-gray matter structures (caudate, putamen); this multifocal process results in the uneven formation of small, apparently empty, microscopic vacuoles of varying sizes within the neuropil and sometimes the perikaryon of neurons.
- In this affected site in the brain (the geniculate nucleus) multiple vacuoles can be seen – this is the typical appearance of the substance of the brain in these diseases that has been said to resemble a sponge*
- Showing the numerous reactive astrocytes*
What is the card showing from Alzheimer’s Disease?
A Plaques with dystrophic neurites surrounding amyloid cores are visible (arrows)
B Plaque core and surrounding neuropil are immunoreactive for AB.
C Neurofibrillary tangle is present within one neuron, and several extracellular tangles are also present (arrows)
D Silver stain showing a neurofibrillary tangle within the neuronal cytoplasm
E Tangle (upper left) and neurites around a plaque (lower right) contain tau, demonstrated by immunohistochemistry.
- What specific anatomical region of the brainstem is this?
- Describe the abnormalities seen on staining:
- Locus coeroleus in the pons
- Lewy body, lewy neurites, granular cytoplasm
