2. Stroke or CVA is defined as abrupt onset of
neurologic deficit that is attributable to a
focal vascular cause.
Stroke has occured if the neurologic signs
and symptoms last for >24 hours
3. It is composed of the paired vertebral
artery,basilar artery&paired PCA’s
These major arteries give rise to short&long
circumferential branches that supply the
cerebellum,medulla,pons,midbrain,thalamus,hipp
ocampus and medial temporal&occipital lobes
PCA syndromes usually result from atheroma or
emboli at the top of basilar artery,fibromuscular
dysplasia or vertebral artery dissection
4.
5.
6. P1 SYNDROME:infarction usually occurs in the
I/L subthalamus&medial thalamus and in I/L
cerebral peduncle&midbrain
P2 SYNDROME:Cortical temporal and occipital
lobe signs
7. The VERTEBRAL artery has 4 segments
V1,V2,V3&V4
The fourth segment courses upward to join
the other vertebral artery to form the basilar
artery
Only V4 gives rise to branches that supply the
brainstem&cerebellum
The PICA,in its proximal segment supplies the
lateral medulla and in its distal branches the
inferior surface of cerebellum
8.
9. ON SIDE OF LESION:
1) Pain,numbness,impaired sensation over
one-half of face:5th nerve nucleus
2) Ataxia:restiform body,cerebellar
hemisphere,spinocerebellar tract
3) Nystagmus,diplopia,vertigo,nausea,vomting
:vestibular nucleus
4) Horner’s syndrome:descending sympathetic
tract
5) Dysphagia,paralysis of palate,vocal
cord,diminished gag reflex:fibres of
9th&10th nerves
10. 6)Loss of taste:nucleus&tractus solitarius
7)Numbness of I/L arm,trunk&leg:
cuneate&gracile nucleus
8)Weakness of lower face:UMN fibres to I/L
facial nucleus
ON SIDE OPPOSITE LESION:
1) Impaired pain&thermal sense over half the
body,sometimes face:Spinothalamic tract
11. On the side of lesion:
1) Paralysis with atrophy of half the tongue:
I/L 12th nerve
On the side opposite lesion:
1) Paralysis of arm&leg sparing face;impaired
tactile&proprioceptive sense over one half
of the body:C/L pyramidal tract&medial
leminiscus
12. Branches of basilar artery supply the base of
the pons&superior cerebellum and fall into
3 groups:
1) Paramedian,7-10 in number supply a wedge
of pons on either side of midline
2) Short circumferential,5-7 that supply lateral
two-thirds of pons&middle,superior
cerebellar peduncle
3) B/L long circumferential(SCA&AICA) course
around pons to supply the cerebellar
hemispheres
13.
14. MEDIAL INFERIOR PONTINE SYNDROME:
ON THE SAME SIDE:
1) Paralysis of conjugate gaze to the side of
lesion
2) Nystagmus:vestibular nucleus
3) Ataxia:middle cerebellar peduncle
4) Diplopia on lateral gaze:abducens nerve
ON THE OPPOSITE SIDE:
1) Paralysis of face,arm&leg:CB&CS tracts
2) Impaired tactile&proproiceptive sense over
one-half of body:medial leminiscus
15. LATERAL INFERIOR PONTINE (AICA)
SYNDROME:
ON THE SIDE OF LESION:
1) Horizontal&vertical gaze
nystagmus,vertigo,nausea,vomting:vestibula
r nerve or nucleus
2) Facial paralysis:7th nerve
3) Ataxia:middle cerebellar
peduncle&cerebellar hemisphere
4) Impaired sensation over face:descending
tract&5th nucleus
ON THE SIDE OPPOSITE LESION:
1) Impaired pain and thermal sense over one-
half of body
16.
17. ON THE SIDE OF LESION:
1) Ataxia of limbs and gait-pontine nucleii
ON THE SIDE OPPOSITE LESION:
1) Paralysis of face,arm&leg:corticobulbar and
corticospinal tracts
2) Variable impaired touch and
proprioception:medial leminiscus
18. ON THE SIDE OF LESION:
1) Ataxia:middle cerebellar peduncle
Paralysis of muscles of mastication:motor
fibres or nucleus of 5th nerve
ON THE SIDE OPPOSITE LESION:
1) Impaired pain and thermal sense on limbs
and trunk:spinothalamic tract
19.
20. MEDIAL SUPERIOR PONTINE SYNDROME:
ON THE SIDE OF LESION:
1) Cerebellar ataxia:superior/middle cerebellar
peduncle
2) Internuclear ophthalmoplegia:MLF
3) Myoclonic syndrome,palate,pharynx,vocal
cords-dentate projection,inferior olivary
nucleus
ON THE SIDE OPPOSITE LESION:
1) Paralysis of face,arm&leg:CB&CS tract
2) Rarely touch,vibration&position:medial
leminiscus
21. LATERAL SUPERIOR PONTINE
SYNDROME OR SCA OR MILLS’
SYNDROME:
ON SIDE OF LESION:
1) Ataxia:middle&superior cerebellar
peduncles,dentate nucleus
2) Dizziness,nausea,horizontal
nystagmus:Vestibular nucleus
3) Horner’s syndrome:descending sympathetic
tract
4) Tremor:red nucleus,superior cerebellar
peduncle
22. ON SIDE OPPOSITE LESION:
1) Impaired pain&thermal sense on
face,limbs&trunk:spinothalamic tract
2) Impaired touch,vibration&position
sense:medial leminiscus
23. MILLARD-GUBLER SYNDROME:I/L LMN type
facial nerve palsy&C/L hemiparesis due to
involvement of 7th nerve nucleus&CST
FOVILLE’S SYNDROME:I/L LMN type facial
nerve palsy&horizontal gaze palsy with C/L
hemiparesis due to involvement of horizontal
gaze centre,7th nerve nucleus&CST
RAYMOND’S SYNDROME:I/L abducens palsy
C/L hemiparesis due to involvement of 6th
cranial nerve&CST
24.
25. MEDIAL MIDBRAIN SYNDROME:
1) ON THE SIDE OF LESION:Eye”down&out”
secondary to unopposed action of 4th&6th
cranial nerves,with dilated&unresponsive
pupil(3rd cranial nerve)
2) ON SIDE OPPOSITE LESION:paralysis of
face,arm,leg(CB&CS tracts in crus cerebri)
LATERAL MIDBRAIN SYNDROME:
1) ON THE SIDE OF LESION:eye down&out
2) ON THE OPP. SIDE:
hemiataxia,hyperkinesias,tremor:Red
nucleus,dentatorubrothalamic pathway
26. WEBER’S syndrome:third nerve palsy on the
I/L side due to involvement of occulomotor
nerve fascicles,Hemiplegia on C/L side due to
superior cerebral peduncle involvement
CLAUDE’S syndrome:I/L 3rd nerve palsy,C/L
ataxia&tremor due superior cerebellar
peduncle involvement
BENEDIKT’S syndrome:3rd nerve palsy on I/L
side&C/L side hemiparesis&ataxia due
involvement of red nucleus,SCP
27. Lesion is dorsal midbrain
Structures involved are quadrigeminal plate
region,periaqeuductal gray matter
Clinical findings: impaired upgaze;
convergence&retraction nystagmus
NOTHNAGEL’S SYNDROME:it is more a variant
of parinaud’s with U/L or B/L 3rd nerve
palsy.lesion is in midbrain tectum
28. C/L homonymous hemianopia with visual sparing
is the usual manifestation
ACUTE MEMORY DISTURBANCES:due to medial
temporal lobe&hippocampus involvement on the
dominant side
ALEXIA without agraphia:due to dominant
hemisphere plus splenium of corpus callosum
involvement
PEDUNCULAR HALLUCINOSIS:due to occlusion of
PCA
29. ANTON’S syndrome:B/L infarction in distal
PCA produces cortical blindness
If the visual association areas are spared and
only calcarine cortex is involved,patient may
be aware of his blindness
BALINT’S syndrome:disorder of orderly visual
scanning of the environment due to bilateral
visual association area lesions,resulting from
infarctions secondary to low flow in the
watershed areas between the distal PCA&MCA
territories
Pallinopsia&asimultognosia may also be seen
