Anatomy of space occupying lesions Flashcards
What are the 5 layers to the scalp?
SCALP: Skin Connective tissue Aponeurosis Loose connective tissue Pericranium
What is the pterion?
H shaped suture: Frontal Parietal Temporal Sphenoid
Where does the middle meningeal artery run?
Over the pterion to supply the skull bone
What runs in the foramen spinosum?
Middle meningeal artery
What runs in the jugular foramen (vascular)?
Internal jugular vein
What are the 3 layers of meninges?
Dura
Arachnoid
Pia
Describe the dura mater
Tought/fibrous
Sensory nerve supply from CN 5
Encloses dural venous sinuses between the periosteal and meningeal layer
Describe the arachnoid mater
Arachnoid granulations that reabsorb CSF
What is the tentorium cerebelli?
Sheet of dura mater that “tents” over the cerebellum
Attaches to the petrous temporal bone
What is the diaphragm sellae?
Tough sheet of dura mater forming a roof over the pituitary fossa
What is the falx cerebri?
Midline structure
Made of dura mater
Attaches to the crista galli anteriorly and the internal occipital protuberance posteriorly
What drains the brain directly?
Cerebral vein
Where will the cerebral veins drain into?
Dural venous sinuses
Where can you find the superior sagittal sinus?
Running along top of brain along sagittal sinus
What will the sigmoid sinus become?
Internal jugular vein as it passes through the jugular foramen
Where is the confluence of sinuses?
Midline at the internal occipital protuberance
What will the vertebral arteries become?
Basilar artery
What will the vertebral arteries pass through in the cervical foramen?
Transverse foraminae
What will the anterior cerebral artery supply?
Medial aspect of cerebral hemisphere
What will the posterior cerebral artery supply?
Posterior aspect of cerebral hemispheres including the visual cortex
Where is the circle of willis suspended?
Subarachnoid space - bathed in CSF
What part of the ventricles produces CSF?
Choroid plexus
Where does the subarachnoid space end?
S2
What is the name of the connection between the lateral ventricles and the 3rd ventricle?
Foraminae of monroe
What is hydrocephalus?
Excessive production, obstruction to flow or inadequate reabsorption leading to an increased CSF olume
What is an extradural haemorrhage?
Bleeding between bone and dura
Ruptured middle meningeal artery
Trauma to pterion
What is a subdural haemorrhage?
Separates dura from arachnoid
Torn cerebral vein
Falls in elderly
What is a subarachnoid haemorrhage?
Bleeding into CSF
Ruptured berry aneurysm
Congenital aneurysm
What are the different types of supratentorial herniation?
Cingulate
Central
Uncal
Transcalavarial
What is an uncal herniation?
Uncus (medial part) of temporal lobe herniates inferior to the tentorium cerebelli
What is a common sign of an uncal herniation?
Blown pupil
What are the different types of infratentorial herniation?
Upward
Tonsillar
What is a tonsillar herniation?
Cerebellar tonsils herniate into the foramen magnum