8 - Radiography of the Skull and Brain Flashcards
What cranial fossa do each of the lobes of the brain sit in?
- Anterior: frontal
- Middle: temporal
- Posterior: occipital, brain stem, cerebellum
What are the tentorium cerebelli and the falx cerebri attached to?
FC: Crista Galli to TC. Slots down longitudinal fissure
TC: Clinoid and Petrous processes laterally to the transverse sinus grooves posteriorly
What is A and why is it black?
- Lateral ventricles - filled with CSF.
- Any subarachnoid space will be black due to CSF
What is cortical homunculus?
How do lesions of the cerebellum present?
- Ipsilaterally
- Sensitive to alcohol
- Many important functions e.g. modulating and co-ordinating voluntary motor activity e.g. speech, eye movements, limbs, and in maintaining balance and posture
What colour is acute and chronic haemorraghes on a CT scan?
Acute: lighter more white
Chronic: darker
What is anisocoria?
- Unequal size of the eyes’ pupils
How could a subdural haemorraghe cause anisocoria and how is it treated?
- Uncal herniation onto oculomotor nerve
- Craniotomy and evacuation
What is paresis?
- Muscles weakness
- When figuring out what side has paresis think about decussation
Where is the cingulate gyrus and the calcarine sulcus?
What is the role of the frontal lobe?
behaviour, personality and planning and motor cortex
What symptoms would you get in a cavernous sinus thrombosis?
- Orbital Oedema due to blockage of IJV
- Diplopia and Ptosis due to interruption of CN III, IV, VI
- Pain/Numbness on side of face as sensory trigeminal
- No issue with mastication as Vc not in cavernous sinus
Which cranial nerves move the eyeball?
- Abducens
- Trochlear
- Occulomotor
What makes up the forebrain?
Cerebrum and Diencaphelon (hypo/thalamus)
What cranial nerves are involved in the corneal reflex?
- Va sensory afferent
- VII motor efferent
Which lobe has the metastatic lesion?
- Left cerebellum
- Remember MRIs and CTs look up
- Optic nerve is an extension of forebrain so the ICP has irritated and compressed this nerve
- Wouldn’t be the oculomotor nerve as this is affected by herniation of the temporal lobe
Why may someone have CSF rhinorrhoea when presenting with this?
- Basillar skull fracture
- Tear in the dura
- CSF can get from dura through the fracture
What nerves is the gag reflex and saying AHH testing?
Gag: Glossopharyngeal and vagus
Ahh: vagus, both sides of soft pallate should elevate. If to one side, lesion is opposite side
What is the role of the supra and infrahyoid muscles when swallowing?
Describe in detail the phases of swallowing.
How do you manage a peritonsillar abscess?
What secondary condition can acoustic neuroma lead to?
Bells Palsy
