H&N - Brain Flashcards
Sinuses of the brain
Meninges of the brain
Dura
Arachnoid
Pia
Falx cerebri
Inner meningeal layer of dura mater
Diaphragm sellae
Covers hypophysial fossa
Has an opening to allow infundibulum of pituitary to connect to base of brain
It’s reflection of dura mater
Arterial supply to dura mater
Anterior meningeal artery
Middle meningeal artery
Posterior meningeal artery
Anterior meningeal artery branch of?
Ethmoid arteries
Middle meningeal artery branch of
maxillary artery
Posterior meningeal artery branch of
Ascending pharyngeal
Occipital
Vertebral
Where is CSF produced
Choroid plexus in lateral, 3rd and 4th ventricles
Where is CSF reabsorbed
Through arachnoid villi which project as clumps (arachnoid granulations) in superior sagittal sinus
Branches of internal carotid artery
Only press carotid arteries momentarily
Only = Opthalmic Press = Posterior communicating Carotid = Choroidal Arteries = Anterior cerebral Momentarily = Middle cerebral
Circle of Willis anatomy
Branches of vertebral artery
Anterior spinal
Posterior spinal
Posterior inferior cerebellar
Branches of basilar artery
Anterior inferior cerebellar artery
pontine arteries
Superior cerebellar artery
Posterior cerebellar artery
Dural venous sinuses
Structures draining into dural sinuses
Diploic veins
Emissary veins (allow infection from outside in)
Structures passing through cavernous sinus
CN6
internal carotid artery
Structures passing through lateral wall of cavernous sinus
CN3, 4, V1, V2
Significance of these structures going through the cavernous sinus
Facial tumours and infection drained by facial vein into cavernous sinus → thrombosis
Presents a progressive loss of vision and CN3,4,5,6 palsies
Parasympathetic ganglia
Ciliary
Pterygopalatine
Otic
Submandibular
Nerve of ciliary ganglion
Oculomotor
Function of ciliary ganglion
Pupillary constriction
Eye accommodation
Pterygopalatine ganglion nerve
Greater petrosal nerve: facial nerve
Function of pterygopalatine ganglion function
Innervation of
Lacrimal gland, mucous glands of nasal cavity, maxillary sinus and palate
Otic ganglion nerve
lesser petrosal nerve of CN9
Otic ganglion function
Innervation of parotid gland
Submandibular ganglion nerve
chorda tympani to lingual (CN7)
Function of submandibular ganglion
innervation of submandibular and sublingual glands
Clinical finding in oculomotor palsy
Dilated pupil
Eye go down and out
Clinical findings in trochlear palsy
Eyes cant look down and in
cant look downstairs
Gross anatomy of saggital section of brain
thalamus surrounds 3rd ventricle
Mamillary bodies inferior surface of hypothalamus
Which part of cortex responsible for sensory/motor
Precentral gyrus motor
Post central gyrus sensory
Position of Brocca vs Wernicke’s areas
Brocca- expressive speech, frontal lobe : Brodman area 44,45
Wernickes- receptive speech, temporal lobe: Brodman area 22
Hypothalamus anatomy
pituitary attached inferiorly by infundibulum (pituitary stalk)
mamillary bodies anterior
floor of 3rd ventricle
Which cranial nerve doesnt originate from brainstem
CN11
Forms from roots of top 5 cervical spine
Goes up through foramen magnum
Comes down through Internal jugular foramen
Course of vertebral artery
Originates at subclavian
Climbs up between anterior scalene and longus coli
Enters transverse foramen of C6 → C1
Goes along the posterior arch of C1 to enter skull through foramen magnum
Joins the other side in front of medulla oblongata to become basilar artery
Course of CSF from lateral ventricles
Lateral V – Foramen of munro → 3rd V
3rd V – Aqueduct of Sylvius → 4th V
– foramen magendie (medial-posterior) → subarachnoid space
– foramen Luschka (lateral-anterior) → subarachnoid space
Gyri vs sulci
Gyrus: raised parts of cortex
Sulcus: groove between two gyri
What forms white and grey matter
Grey matter:
- neural cell bodies
- More superficial
- Processing information
White matter:
- Axons
- Deeper
Superficial cerebral fissures
Fissure: deeper sulcus, mainly used interchangeably
Longitudinal (between frontal lobes)
Sylvius (between temporal and fronto-parietal)
Rolando (between frontal and parietal)
Where is the Calcarine sulcus
Deep fissure separating occipital lobe into lingual (inferior) and cuneus (superior) gyri
Visual cortex lies either side of this sulcus
Branches of vagus nerve
7:
Meningeal (sensory to dura in posterior cranial fossa)
Auricular
Pharyngeal plexus
Superior laryngeal
Recurrent laryngeal
Carotid sinus
PSN to thorax and abdomen
Origin of cranial nerves
CN1 and 2: nuclei in forebrain
CN3-4: Midbrain
CN5: Pons
CN6-8: Pons/Medulla junction
CN9-11: Medulla
CN12: cervical spine
Cerebellar anatomy
Vermis: midline section (associated with locomotion)
Vallecula: the gap at the bottom of the cerebellum where vermis disappears
Function of basal ganglia
Co-ordinates movement
Nuclei of basal ganglia
Located at the base of cerebral hemispheres
Caudate nucleus
Putamen
Globus pallidus
Substantia nigra
Subthalamic
Extradural vs subdural haemorrhage causes
Extra: cerebral artery eg middle meningeal
Subdural: cerebral veins draining into venous sinuses
Extradural vs subdural on CT
Extra: lens like
Subdural: crescent like
