Neurovascular

Question 1

Internal carotid

Answer 1

Branch of common carotid (at C4)
Enters cranium via carotid canal of temporal bone
Branches:
Ophthalmic artery
Posterior communicating artery
Anterior cerebral artery
Anterior choroidal artery
Middle cerebral artery

Question 2

Vertebral artery

Answer 2

Enters via foramen magnum
Branches:
Meningeal branches
Anterior and posterior spinal arteries
Posterior inferior cerebellar artery
Forms basilar artery

Question 3

Circle of Willis

Answer 3

Anterior cerebral arteries (branch of ICA)
Internal carotids
Posterior cerebral arteries (branch of BA)
“Connecting vessels”:
Anterior communicating (connects anterior cerebral arteries)
Posterior communicating (connects ICA with posterior cerebral)

Question 4

Basilar arteries

Answer 4

Formed by two vertebral arteries over junction of medulla and pons
Branches:
Anterior inferior cerebellar artery
Pontine arteries
Superior cerebellar arteries
Posterior cerebral arteries

Question 5

Stroke syndromes

Answer 5

Anterior cerebral artery syndrome
Middle cerebral artery syndromes
Poster cerebral artery
Anterior inferior cerebellar artery (AICA)
Posterior inferior cerebellar artery (PICA)

Question 6

Anterior cerebral artery syndrome

Answer 6

Rare due to collateral flow
Contralateral hemiparesis of lower limbs
Contralateral sensory loss of lower limbs
Anosmia

Question 7

Middle cerebral artery syndromes

Answer 7

Contralateral weakness
Contralateral sensory loss
Contralateral hemineglect
Contralateral homonymous hemianopia
Global aphasia (receptive and expressive)

Question 8

Basilar artery

Answer 8

Locked in syndrome

Question 9

Anterior inferior cerebellar artery (AICA)

Answer 9

Lateral pontine syndrome: Marie-Fox Syndrome
Ipsilateral cerebellar ataxia (arm and leg)
Ipsilateral facial weakness
Ipsilateral hearing loss, vertigo and nystagmus

Question 10

Posterior inferior cerebellar artery (PICA)

Answer 10

Lateral medullary syndrome (Wallenberg Syndrome)

Ipsilateral:
Facial sensory loss
Nystagmus
Horner's syndrome
Loss of gag reflex
Ipsilateral ataxia with a tendency to fall to the ipsilateral side
Contralateral:
Pain and temperature sensory loss in the extremities

Question 11

Dural venous sinuses

Answer 11

Lie between periosteal and meningeal dural layers
Drain into internal jugular vein
11 sinuses in total

Question 12

Superior sagital sinus

Answer 12

Runs in falx cerebri
Collects from Superior cerebral veins
Connects with confluence of sinuses at internal occipital protuberance

Question 13

Confluence of sinuses

Answer 13

Collection of:
Superior sagital sinus
Straight sinus
Occipital sinus

Drains into
R & L transverse sinuses

Question 14

Inferior sagital sinus

Answer 14

Runs in falx cerebri in midline

Connects with great cerebral “vein of Galen” into: Straight sinus

Question 15

Inferior sagital sinus

Answer 15

Runs in falx cerebri in midline

Connects with great cerebral “vein of Galen” into: Straight sinus

Question 16

Great cerebral vein “Of Galen”

Answer 16

formed by joining of internal cerebral vein and basal vein of Rosenthal.
Joins with inferior sagital sinus to from straight sinus

Question 17

Transverse sinus

Answer 17

Right and left
Drains from confluence of sinuses
Drains into sigmoid sinus

Question 18

Cavernous sinus

Answer 18

Venous plexus on each side of sella turcica
CN3, CN4, CNV1, CNV2, CN6 and ICA travel though it.
Collects from inferior and superior ophthalmic veins
Drains into superior and inferior petrosal sinuses (onto transverse sinus and IJV)

Question 19

Functions of CSF

Answer 19

Protection
Buoyancy
Chemical stability

Question 20

Ventricles of the brain

Answer 20

Lateral ventricle
Third ventricle
Fourth ventricle

Question 21

Lateral ventricle

Answer 21

R & L. Located within hemispheres of cerebrum.

“Horns” project into frontal, occipital and temporal lobes

Question 22

Third ventricle

Answer 22

Connects to the lateral ventricles by the foramen of Munro

Situated between right and left thalamus

Question 23

Fourth ventricle

Answer 23

Receives CSF from third ventricle via cerebral aqueduct
Lies within brainstem at junction of medulla and pons
Drains into:
Central spinal canal: bathes spinal cord
Subarachnoid cisterns: bathes brain between arachnoid and Pia

Question 24

Production of CSF

Answer 24

Produces by choroid plexus, located in lining of ventricles.

Question 25

Drainage of CSF

Answer 25

``` Occurs in subarachnoid space. Arachnoid granulations (small projections) into dura mater. Allowed fluid to drain into dural venous sinuses. ```

Question 26

Cavernous Venous Sinus Thrombosis

Answer 26

Clot in Cavernous sinus Most common cause: infection. Typically spreads from extracranialu location: orbit, paranasal sinuses or "danger zone" of face. (Connection between ophthalmic veins and CS) Sx: headache, unilateral periorbital oedema, proptosis, CN palsy (CN6 most common). Can rapidly progress to meningitis

Question 27

Neural tube normal embryology

Answer 27

Neural groove --> neural fold --> neural tube Closes at approx day 28 4 divisions: 1. Forebrain (prosencephalon --> telencephalon: cerebrum & diencephalon: optic nerve/hypothalamus) 2. Midbrain (mesencephalon) 3. Hindbrain (rhombencephalon --> metencephalon: pons/cerebrum & myelencephalon: medulla oblongata) 4. Spinal cord

Question 28

Neural tube defects

Answer 28

``` Failure of neural tube to close (day 28) Anencephaly Encephaloceles Hydranencephaly Iniencephaly Spina bifida (most common) ```

Question 29

Anencephaly

Answer 29

Severe. Failure for anterior most part of neural tube to fuse. Leading to lacking most parts of forebrain (cerebrum) Infants die within hours/days of birth

Question 30

Encephalocele

Answer 30

Protusions of cerebral material through skull into sac covered with membranes/skin

Question 31

Hydranencephaly

Answer 31

Cerebral hemispheres are missing and filled with fluid

Question 32

Spina bifida: types

Answer 32

Myelomeningocele Meningocele Spina bifida occulta

Question 33

Spina bifida: Risk factors

Answer 33

Folate deficiency Obesity DM Anti epileptics

Question 34

Myelomeningocele

Answer 34

Most severe type Spinal cord, meninges protrude from spinal column If no skin covering: "open spina bifida" Associated with Arnold-Chiari II malformation

Question 35

Meningocele

Answer 35

Only meninges protruding through unformed spinal column

Question 36

Spina bifida occulta

Answer 36

Most common. Least severe. Spinal cord/surrounding tissue does not protrude. Hair/dimple/birth mark at site of lesion.