Download MBBS (Bachelor of Medicine and Bachelor of Surgery) Anterior Circulation of Brain PowerPoint PPT presentation
CIRCLE OF WILLIS
Anterior circulation:
Originating from Internal Carotid Artery
1)
Middle Cerebral Artery
2)
Anterior Cerebral Artery
3)
Anterior Choroidal Artery.
MIDDLE CEREBRAL ARTERY
Lenticulostriate vessels ?
A) Internal Capsule
B) Caudate Nucleus
C) Putamen
D) Globus Pallidus
Occlusion of these vessels can result
in:
Hemiplegia C/L
Hemisensory loss
Homonymous hemianopia
UMN Facial palsy
In a lenticulostriate occlusion, if caudate and putamen
are affected, there can be Parkinsonian features as
well.
M2 branch- lies in the Sylvian fissure, divides into
TOTAL MCA OCCLUSION:
superior and inferior divisions.
Dominant Lobe:
Occlusion of Superior division- Brocas Aphasia
C/L HEMIPLEGIA
with weakness.
C/L HEMISENSORY LOSS
HOMONYMOUS HEMIANOPIA
Occlusion of Inferior division- Wernickes aphasia
UMN FACIAL PALSY
without weakness.
GLOBAL APHASIA WITH WEAKNESS
Occlusion of stem of M2- Global aphasia with
weakness
Non Dominant-
HHH +7th Nerve UMN palsy+ Visuospatial
disorientation+ Dressing apraxia+Constructional
apraxia+ Hemispatial eglect
ANTERIOR CEREBRAL ARTERY- DIVIDES INTO A1 AND
A2.
A1 SUPPLIES ANTERIOR LIMB OF
A2 SUPPLIES MEDIAL SURFACE OF
IC,
FRONTAL CORTEX.
ANTERIOR CAUDATE NUCLEUS
Its occlusion is definitely
ANT. HYPOTHALAMUS
symptomatic!
Its occlusion is usual y
C/L WEAKNESS, AFFECTING LEGS
asymptomatic.
MOSTLY.
GAIT APRAXIA (ANTERIOR
CINGULATE GYRUS)
URINARY INCONTINENCE
(PARACENTRAL LOBULE LESION)
FRONTAL RELEASE REFLEXES.
ANTERIOR CHOROIDAL ARTERY- SMALL ARTERY THAT
COMES FROM ICA.
Supplies: Posterior limb of Internal
Capsule (lower part).
Remember, that most of the
supply to IC is via the
lenticulostriate arteries. So even if
there is occlusion to Ant.
Choroidal arteries, mild symptoms
are seen atmost.
Symptoms are usual y- HHH
syndrome.
This post was last modified on 12 August 2021