Neurology Flashcards
(185 cards)
Name the meninges in order
Dura mater
Arachnoid mater
Pia mater
Which meninge has two layers which surround the venous sinuses?
Dura mater
Has a periosteal layer and a meningeal layer.
Which meninge contains the cerebrospinal fluid?
Arachnoid mater
Which meninge is tightly bound to the surface of the brain?
Pia mater
Which fascial layers divide the brain into sections? What is their function? What are they made of ?
Falx cerebri
Tentorium cerebelli
Prevent brain rotating within the skull
Made of reflections of dura mater
Which bony ridge does the falx cerebri attach onto?
Crista Galli of ethmoid
What is the blood supply to the scalp?
Aponeurosis of superficial temporal arteries and occipital arteries
Why does the scalp bleed so heavily? Why does the bone underneath not suffer from necrosis?
It is an Aponeurosis direct from external carotid.
The vessels can’t constrict because they are tightly bound to connective tissue
Bone underneath supplied by middle meningeal arteries
What type of bleed from which vessel usually causes an extradural haematoma?
Forceful arterial - usually middle meningeal
What type of bleed from which vessel usually causes an subdural haematoma?
Venous - veins between brain and venous sinuses
What type of patient is particular risk factor for a subdural haematoma?
Elderly with dementia.
Brain atrophies leaving longer sections of veins to sinuses exposed. Smaller brain also means more rotation in the cranial cavity so greater shearing forces.
How would you identify a sub arachnoid haemorrhage?
Pinkish CSF
Mri covered in white
Give 3 functions of cerebrospinal fluid.
Buoyancy and reduced weight
Homeostasis
Mechanical protection
How is CSF produced?
Choroid plexus in the lateral ventricles filters blood
Describe the flow of cerebrospinal fluid through the nervous system.
Produced in lateral ventricles - foramen of monro - 3rd ventricle - cerebral aqueduct - 4th ventricle
Then either - spinal canal or medial and lateral apertures to sub arachnoid space
Drains back to venous sinuses through arachnoid villi
What does a yellowish CSF indicate?
Infection eg meningitis
Which bacteria are implicated in meningitis?
Streptococcus pneumoniae
Or
Neisseria meningitidis
Why is meningitis so dangerous?
Inflammation and oedema raises intracranial pressure
Risk of decreased perfusion and/or cranial herniation (coning)
Give 4 key diagnostic symptoms of meningitis other than fever and headache.
Photophobia
Confusion
Stiff neck
(Later) rash due to sepsis
In which condition is congenital hydrocephalus common? Why?
Spina bifida
Notochord does not close properly so ventricles not complete.
Struggle to maintain pressure of CSF so excess is produced
Name the layers of the scalp
Skin Connective tissue Aponeurosis Loose connective tissue Periosteum
What are the 3 main arteries which are supplied by the circle of Willis?
Anterior middle and posterior cerebral arteries
Which areas of the brain are supplied by the anterior, middle and posterior cerebral arteries?
Anterior - medial full thickness strip, as far back as the occipital lobe
Middle - most of parietal and temporal lobes
Posterior - occipital lobe and inferior temporal lobe
Give 3 key functions of the frontal lobe
Executive function
Decision making
Motor function