This document discusses the localization of stroke based on clinical findings. It covers the basics of stroke classification and vascular territories. Key points include: 1. Stroke is classified as either ischemic (80%) due to thrombosis, embolism or hypoperfusion, or hemorrhagic (20%) due to ICH or SAH. 2. Localizing the site of a stroke lesion involves correlating the clinical exam with the involved vascular territory and imaging findings. 3. Symptoms vary based on the specific region affected, such as frontal lobe dysfunction presenting with behavioral changes while occipital strokes cause homonymous hemianopsia. 4. Different vascular territories include the anterior circulation supplied by

1. Localization of stroke
Dr. Mohammed firoz
Post graduate
Final year
Andhra medical College

2.  stroke, or cerebrovascular accident, is defined
as an acute onset of a neurologic deficit that is
due to a focal vascular cause.
 • Transient Ischemic Attack (TIA) or ‘mini
stroke’ is when those symptoms resolve in 24
hours (usually under 1hr) without evidence of
brain infarction on brain imaging.

3.  Stroke is classified into two major types:
 Brain ischemia due to thrombosis,
embolism, or systemic hypoperfusion (80%).
 Brain hemorrhage due to intracerebral
hemorrhage (ICH) or subarachnoid
hemorrhage (SAH)(20%).

4. Localization of stroke syndromes
Three steps
1.Clinical localization of the site of the lesion.
2.Identifying the vascular territory and the vessel
involved.
3.Correlating with the imaging findings

5.  Prerequisites
 1.Functional anatomy of brain.
 2.Blood supply to the different parts of brain

6.  Cortex functional anatomy

9. Frontal lobe dysfunction
 Emotions,judgement
 Memory,reasoning
 Abstract thinking
 Motor cortex
 Dominent
cortex(brocas area44)
 Non dominant side
 Frontal eye field (8)
 Social disinhibition,
Poor judgement,poor
memory, impaired
abstract
thinking,urinary
incontinence
 Weakness of opposite
 Non fluent aphasia(t)
 Lack of
prosody(expression)
 Contralateral
conjugate horizontal
gaze palsy

10. Parital lobe dysfunction
 Cortical sensations
 optic radiation
 Loss of tactile
localization,
 two point
discriminaton,
 Stereognosis,
 graphesthesia.
 Inferior
quadrantanopia

11. Parital lobe(Dominant) dysfunction
 Ability to perfom
learned motor
activity
 Calculation,writing
Gertsmans syndrome
 Idiomotor
apraxia.imagination
impaired ,can use
real time objects
 Ideational apraxia
Acalculia
Dysgraphia
Finger agnosia
Rt to Lt confusion

12. Parital lobe (non dominant)
 Visuospatial
integration
 Left hemi neglect
 Anosognosia-pt
deny existance of
left limbs
 Constructional and
dressing apraxia

13. Temporal lobe
 Memory
 Emotions (limbic area)
 Wernickes area
 Optic radiations
(visual field)
 Recent
memory(hypocamps)
 Memory of
fear(amygdala)
kluver bucy syndrome
 Emotional distruance
 Wernikes apahsia
without hemiplegia
 Superior
quadrantanopia

14. Occipital lobe
 Visual field areas.
 Occipito temporal
connections.
 Occipito parital
connections.
 Homonymous
hemianopia with
macular sparing
 Propspagnosia(ina
bility to identify
known faces).
 Asimultanagnosia.

15. Circle of willis

16. Anterior circulation
 Anterior cerebral artery Medial surface of the
cerebral hemisphere and internal capsule
 Middle cerebral artery -(M1) basal ganglia and
internal capsule, (M2)Lateral surface of the
hemisphere
 Post communicating artery – internal capsule
 Ant choroidal artery – internal capsule,
thalamus,LGB
 Ophthalmic artery – optic nerve and retina

17. Internal carotid artery
occlusion
 AMOUROSIS FUGAX
 only feature that distinguishes between
internal carotid artery syndrome and MCA
syndrome
 Sudden onset of transient monocular visual
loss
 Curtain pattern moving superior to inferiorly
 Spontaneous, unrelated to position usually
lasting for 1 to 5 minutes rarely beyond 30
mins

18. Blood supply

20.  Internal capsule

21. Internal capsule
 Anterior limb
 genu
 Posterior limb
 Retro&sub
lenticular
 Fronto ponto
cerebellar fibers
 Papez circuit
 Saccadic pathway
 Corticobulbar fiber
 Corticospinal,thalamic
radiations
 Visual and auditory
radiations.

22. Blood supply

23.  LESION AT LEVEL OF INTERNAL
CAPSULE:
 Dense hemiplegia (UL weekness=LL
weeknes)
 Hemisensory loss
 UMN type of facial palsy
 Homonymous hemianopia

24. Occlusion of lenticulostriate vessels leads to lacunar stroke(2mm
to 2cm) with in internal capsule

25. Posterior circulation
 Vertebral artery- medulla and
cerebellum
 Basilar artery pons and cerebellum
 Posterior cerebral artery midbrain,
thalamus, hippocampus, occipital
lobe, temporal lobe and cerebellum

26. Thalamus
 Supplied by deep branches
 of PCA.
 Contalateral hemiplegia.
 Sensory deficit.
 Aphasia, constructional apraxia.
 Homonymous visual defect,horners I/L.
 After Thalamic stroke Dejerine roussy syndrome-
C/l hemisensory loss,burning pain in affected
area

28. Mid brain

30. Mid brain
 Vertical gaze
 3rd &4th cranial
nerve nucleus
 Corticospinal tract
 Substantia nigra
 upward gaze palsy
 Convergence
retraction disorder
 Pupil and lid disorder
(parinaud syndrome)
 L/l 3rd &4th CN palsy
 C/l hemiplegia
 Parkinsons disease

31. P1 syndromes
Webers syndrome
Site: anterior cerebral peduncle ,3rd&7th cranial
nerves, corticospinal tract
Signs:I/L3rd CN palsy,C/L 7th CN palsy UMN,C/L
hemiplegia
Claude syndrome
site: superior cerebellar peduncle ,3rdC/N nucleus
Signs: I/L3rd CN palsy+C/L cerebellar ataxia
nothnagel syndrome
Site:tectum ,superior cerebellar peduncle
Signs:I/L 3rd CN palsy+ C/L cerebellar ataxia

32.  Benedikt syndrome
 Site: tegmentum of mid brain,red
nucleus,corticospinal tract,brachium
conjunctivum
 Signs: I/L 3rd CN palsy,C/L cerebellar
ataxia,tremors,C/L hemiplegia

33.  P2 syndromes
 Antons syndrome
 Site:B/L infract in Distal PCAs
 Sign:cortical blindness,pupillary light reflex
preserved,pt often unaware of blindness
 Balints syndrome
 Site:visual association areas(water shed area)
 Signs:optic ataxia,Asimultagnosia,Oculomotor
apraxia

34. Pons

35. pons
 Horizontal
gaze(pprf)
 5,6,7&8nerve nuclei
 Corticospinal tract
 Millard gubler
syndrome
Raymond-foville
syndrome
 Horizontal gaze
palsy
 I/L 6th&(LMN)7th
CN palsy
 C/L hemiplegia

36. Medulla
 Medial medulla
(posterior column,12th
CN, Cortico spinaltract)
 Lateral medulla
Spinal tract of 5thCN
spinothalamic tract,
vestibular nucleus,
inferior cerebellar
peduncle,sympathetic
tract
Dejerine syndrome
 Hemiesthesia
,hemiplegia,12thCN
palsy
Wallenberg syndrome
 I/L facial sensory
loss with C/L loss of
pain,temp,
nystagmus,vertigo,a
taxia,horners
syndrome

37. cerebellum
 Flocculonodular
lobe (archi
cerebellum)
 Vermis(paleo
cerebellum)
 Cerebellar
hemispheres(neo
cerebellum)
 Eye movement
control and gross
orientation in space
 Concerned with
gait and locomotion
 Concerned with
precise movements
of the extremities

38.  UL weakness>LLweakness=brachial
hemiplegia,MCA territory infract
 UL weakness<LLweakness=crural
hemiplegia,ACA territory infract
 ULweakness=LLweakness=densehemiplegia,
internal capsule infract
 I/L CN&C/L hemiplegia =crossed hemiplegia
 U/L one side &L/L opposite site=Cruciate
hemiplegia= at level of dicussation

39.  My reference Harrison 20th edition
 Uptodate