I. The carotid system.
II. The vertebral system.
1) The ophthalmic artery.
2) The anterior choroidal artery.
3) The posterior communicating artery
II. The Vertebro-Basilar System VOS
brain stem syndromes
22. The middle cerebral artery (MCA) occlusion
Capsular branch occlusion: (lenticulo striate
artery)
Contralateral complete hemiplegia: affecting the
upper and lower limbs to the same extent.
Contralateral hemihyposthesia
Contralateral hemianopia: may occur.
No loss of consciousness or aphasia.
26. The middle cerebral artery (MCA) occlusion
Main artery occlusion( =1+2):
Coma at the onset.
Contralateral hemiplegia affecting U.L. more than
L.L.
Contralateral hemihyposthesia with cortical
sensory loss in U.L.
Contralateral homonymous hemianopia.
Aphasia and agraphia in left sided lesions.
37. The ant cerebral artery (ACA) occlusion
Main artery occlusion( =1+2):
Contralateral hemiplegia affecting L.L. more than
U.L.
Contralateral cortical sensory loss in the lower limb.
Incontinence of urine.
Mentality and personality changes.
Forced grasp reflex.
Apraxia of the left side.
43. Sup. Cerebellar A.
(SCA occlusion)
Ant. Inf. Cerebellar A.
(AICA occlusion)
Post. Inf. Cerebellar A.
(PICA occlusion)
Ipsilateral cerebellar
ataxia √ √ √
Ipsilateral Horner's
syndrome √ √ √
Ipsilateral deafness.
√ X X
Contralateral
hemihyposthesia.
√ √ √
Other features X Ipsilateral 5th, 6th and 7th
cranial nerve paralysis
Bulbar palsy
Ipsilateral loss of pain and
temperature sensations over
the face.
Acute onset associated with
syncope, hiccup, vomiting and
vertigo.
45. Partial occlusion (insufficiency) Complete occlusion (usually fatal)
- Syncope, diplopia and
ophthalmoplegia.
- Vertigo or tinnitus.
- Bulbar palsy
- Hemiparesis, hemianaesthesia
- Ataxia.
- Deep coma.
- Complete quadriplegia with
decerebrate rigidity.
- Bulbar paralysis.
- Respiratory embarrassment.
.1Basilar artery (main vessel )occlusion
Clinical features of partial and complete occlusion of basilar artery.
46. The posterior cerebral artery
It gives the following branches:
Capsular branch supplying the ventral half of
the posterior limb of the internal capsule,
the thalamus and the geniculate bodies
(Thalamogeniculate artery).
Cortical branches to the occipital lobe.
Posterior communicating artery.
48. Posterior cerebral artery occlusion
thalamoqeniculatebranch: (Ganalionic
artery) occlusion= thalamic syndrome:
Thalamic pain i.e. constant burning severe pain in the hemianaesthetic
side.
Complete contralateral hemianaesthesia to all types of sensations.
Reflex dystrophy of the shoulder girdle and arm, secondary to the pain.
Choreo-athetosis or hemiballismus due to ischaemia of the basal
ganglia and/or subthalamus.
Cortical branches occlusion:
Contralateral homonymous hemianopia with macular sparing.
Visual agnosia in left sided lesions.
52. Posterior cerebral artery occlusion
thalamoqeniculatebranch: (Ganalionic
artery) occlusion= thalamic syndrome:
Thalamic pain i.e. constant burning severe pain in the hemianaesthetic
side.
Complete contralateral hemianaesthesia to all types of sensations.
Reflex dystrophy of the shoulder girdle and arm, secondary to the pain.
Choreo-athetosis or hemiballismus due to ischaemia of the basal
ganglia and/or subthalamus.
Cortical branches occlusion:
Contralateral homonymous hemianopia with macular sparing.
Visual agnosia in left sided lesions.
53. Posterior cerebral artery occlusion
):2+1Main vessel occlusion ( =
Thalamic syndrome
Contralateral homonymous hemianopia with macular
sparing as the macula has double blood supply.
Visual agnosia in left sided lesions.