Lecture 3-Meninges and Dural Folds Flashcards
Describe the order of the meningeal layers from closest to the skull to closest to the brain and describe their structure
Dura - tough, fibrous membrane
Arachnoid - soft, translucent membrane
Pia - thin
What are the two layers of dura?
Periosteal - endosteum lining inner bones of the skull
Meningeal - layer adjacent to arachnoid
How do dural venous sinuses form?
Separation of the two dural layers
What are the two types of dural folds?
Falx cerebri
Tentorium cerebelli
Where is falx cerebri present and what are its associated sinuses?
Fold between hemispheres
Superior and inferior sagittal sinuses
Where is tentorium cerebelli present and what is its associated sinuses?
Above cerebellum
Transverse sinus
What is the function of the dural folds and what is the implication of this?
Stabilises brain and acts as rigid dividers but rise in pressure inside skull can lead to compression and displacement of brain against these folds -> herniation through foramen magum
Which veins connect cerebral veins to dural veins?
Bridging veins
Where does an extradural haemorrhage occur?
Between bones and dura
Where does a subdural haemorrhage occur?
Under dura
Where does a subarachnoid haemorrhage occur?
Between pia and arachnoid
For the following, state whether they are due to arterial or venous bleeds:
1) Extradural haemorrhage
2) Subdural haemorrhage
3) Subarachnoid haemorrhage
1) arterial
2) venous
3) arterial
