4.7 Venous Drainage Brain

Question 1

Venous drainage of the cerebral circulation

Answer 1

Superficial and Deep

Superficial

Cortices of cerebrum and cerebellum

Drawn into superficial superficial dural Venus sinuses

• Walls composed Dura
• ->owing to position between 2 layers cranial Dura

Superior sagittal sinus

Inferior Sagittal sinus

Confluence of sinuses
Point Sup + Deep meet

2 TV sinuses

Question 2

Superior sagittal sinus

Answer 2

Lies between 2 cerebral hemispheres
within falx cerebri
Draining into L + R TV sinus
Along border between middle and posterior cranial fossae

Question 3

Inferior Sagittal sinus

Answer 3

Runs in same plane
Above corpus callosum
Joining straight sinus to anastomose
w/ its superior neighbour

Question 4

TV sinuses

Answer 4

bend in S shape 
on border tentorium cerebelli
Forming sigmoid sinuses 
join inferior petrosal sinus
form IJ

Question 5

Deep Drainage

Answer 5

Intra parenchymal vessels
Traditional composition

Join behind midbrain -> Vein of Galen

Vein merges w/ Inferior sagittal sinus
-> Straight sinus

Question 6

Risk factors for CVT

Answer 6

1. Stasis
   Low flow
   Dehydration
   Thrombocythemia
2. Vessel wall trauma
   Exposing sub endothelial collagen
   Recent surgery
3. External compression
   Abscess - paranasal sinus common
   Tumour
   Postop swelling oedema
4. Systemic RF

Question 7

Systemic RF

Answer 7

1. Pregnancy
   Antenatal + Postnatal

2. Hypercoagulable
Caner
AP-Lipid
FV Leiden
OCP
Hyperhomocysteinaemia (strong RF ~35% patients)

3. IBD
4. Haematological conditions
   Parox nocturn HBuria / SCD/ Polycyhtemia
5. Collagen vascular diseases
   SLE
6. Infection
   Meningitis mastoiditis sinusitis
7. Surgery H+N
8. Venous sinus trauma

Question 8

Clinical Features

Answer 8

1. Symptoms
2. Signs
3. Rarely

Cavernous sinus extension - proptosis + periorbital oedema

Symp usually unilateral
can extend to be bilateral
Represent extension to contralateral side

Question 9

1. Symptoms

Answer 9

Hache
N+V
LOC
Fever
Diffuse encephalopathy

Question 10

2. Signs

Answer 10

Seizures
Raised ICP
FND

Question 11

3. Rarely

Answer 11

CN palsy
Cerebellar Sx
Hemiparesis / hemisensory loss
Migraine + Aura
TIA
Tinnitus