The Eye, Visual Field Defects

1
The Eye, Visual Field Defects Eye Movement
Aaron Pennell M.Sc
2
The Visual Pathway
3
Key anatomy
4
Key anatomy
5
(No Transcript)
6
Temporal
Nasal

• Optic disc
• Optic nerve head
• Optic nerve

• Macula
• Fovea
• Fovealis

7
(No Transcript)
8
(No Transcript)
9
Retina
Chiasma
Optic Nerve
LGB
Lower fibres (Temp lobe)
Optic radiation
Occipital Cortex
Upper fibres (ant parietal lobe)
10
(No Transcript)
11
(No Transcript)
12
(No Transcript)
13
(No Transcript)
14
Retina
Chiasma
Optic Nerve
LGB
Lower fibres (Temp lobe)
Optic radiation
Occipital Cortex
Upper fibres (ant parietal lobe)
15
Retina
Chiasma
Optic Nerve
LGB
Lower fibres (Temp lobe)
Optic radiation
Occipital Cortex
Upper fibres (ant parietal lobe)
16
Retina
Chiasma
Optic Nerve
LGB
Lower fibres (Temp lobe)
Optic radiation
Occipital Cortex
Upper fibres (ant parietal lobe)
17
Retina
Chiasma
Optic Nerve
LGB
Lower fibres (Temp lobe)
Optic radiation
Occipital Cortex
Upper fibres (ant parietal lobe)
18
Retina
Chiasma
Optic Nerve
LGB
Lower fibres (Temp lobe)
Optic radiation
Occipital Cortex
Upper fibres (ant parietal lobe)
19
Retina
Chiasma
Optic Nerve
LGB
Lower fibres (Temp lobe)
Optic radiation
Occipital Cortex
Upper fibres (ant parietal lobe)
20
The Eye Muscles
21
(No Transcript)
22
Extra Ocular Eye Muscles
23
(No Transcript)
24
(No Transcript)
25

• Lateral Rectus
• Origin tendinous ring on bony orbit around
  optic foramen
• Insertion lateral wall of eyeball
• Action turns eye laterally

26

• Medial Rectus
• Origin tendinous ring on bony orbit around
  optic foramen
• Insertion Medial wall of eyeball
• Action turns eye medially

27

• Superior Rectus
• Origin tendinous ring on bony orbit around
  optic foramen
• Insertion Superior and central part of eyeball
• Action turns eye upwards and outwards

28

• Inferior Rectus
• Origin tendinous ring on bony orbit around
  optic foramen
• Insertion inferior and central part of eyeball
• Action turns eye downwards and inwards

29

• Superior Oblique
• Origin tendinous ring on bony orbit around
  optic foramen
• Insertion between superior and lateral recti
  muscles
• Action rotates eyeball on its axis directs
  cornea downwards and laterally
• (note via the trochlear)

30

• Inferior Oblique
• Origin maxilla (front of orbital cavity)
• Insertion between inferior and lateral recti
  muscles
• Action rotates eyeball on its axis directs
  cornea upwards and laterally

31
Superior Rectus Muscle
32
Nose
Superior Oblique
33
Superior Rectus
Inferior Oblique
Medial Rectus
Inferior Rectus
Superior Oblique
Lateral Rectus
34
R Superior Rectus L Inferior Oblique
Both Superior Recti Inferior Oblique
R Inferior Oblique L Superior Rectus
R Lateral Rectus L Medial Rectus
R L Primary Position
R Medial Rectus L Lateral Rectus
R Inferior Rectus L Superior Oblique
R Superior Oblique L Inferior Rectus
Both Inferior Recti Superior Oblique
35
Superior Rectus Inferior Oblique
Inferior Rectus Superior Oblique
36
Left VI Nerve Palsy (lateral Rectus)
37
Left IV Nerve Palsy Superior Oblique)
38
Left III Nerve Palsy
39
(No Transcript)
40
Lateral Rectus VI cranial nerve (Abducens)
41
Lateral Rectus VI cranial nerve (Abducens)
Superior Oblique IV cranial nerve (Trochlear)
42
Lateral Rectus VI cranial nerve (Abducens)
Superior Oblique IV cranial nerve (Trochlear)
All others III cranial nerve (Occulomotor)
43
The Pupils
44
Pupils

• Parasympathetic
• Originate from the subnucleus of the III nerve
  and synapse in the cilliary ganglion
• Supplies the constrictor pupillae of the iris
• Sympathetic
• Originate in the hypothalamus, pass down the
  brain stem, cervical spine to emerge at T1 and
  return to the eye

45
Pupils

• Lesions of the sympathetic pathway produce
  Horners syndrome
• Constricted pupil
• Partial ptosis
• Unilateral Ahydrosis
• Optic nerve lesions produce Afferent defects
• Impairs direct response to light
• Consensual response unaffected in diseased eye
• III nerve lesions, cilliary ganglion and
  sympathetic supply produce Efferent disorders of
  the pupil

46
Afferent Pathway
Efferent Pathway
Cilliary Body - Iris
Optic Nerve
Cilliary Ganglion
Convergence Centre
Lateral Geniculate Body
Edinger Westphal Nucleus of III
Pretectal Nucleus
47
Pupils
Afferent Optic nerve (II) Efferent
Occulomotor (III)
Direct Pupil Reaction to Light
48
Pupils
Afferent Optic nerve (II) Efferent
Occulomotor (III)
Consensual Pupil Reaction to Light
49
Pupils
Diseased Eye
Afferent Optic nerve (II) Efferent
Occulomotor (III)
Afferent Pupil Defect
50
Pupils
Diseased Eye
Afferent Optic nerve (II) Efferent
Occulomotor (III)
Afferent Pupil Defect no pupil response
51
Pupil defects

• RAPD Marcus Gunn Pupil
• Partial Damage to optic nerve (therefore Afferent
  defect)
• Pupils symmetrical but degree of dilation is
  variable
• Retrobulbar neuritis etc
• Use swinging torch test to detect affected
  pupil
• Argyle Robertson Pupil
• Mid brain lesion, Neuro-syphilis
• Small irregular pupils, fixed to light but
  constricts on convergence
• Holmes Adie Pupil (Adie pupil)
• Cilliary ganglion lesion
• Unilateral Fully dilated pupil, un-reactive to
  light
• III Nerve Palsy
• Dilated pupil Infero-lateral position of the
  eye, complete ptosis

52
The Retina
53
Temporal
Nasal
54
Key anatomy
55
(No Transcript)
56

• Basic Retinal pathology
• Papilloedema
• Macular degeneration
• Retinopathy maculopathy
• Hypertensive retinopathy
• Detached Retina

57
(No Transcript)
58
Macular Degeneration
59
Diabetic Retinopathy
60
(No Transcript)
61
Hypertensive Changes
62
Diabetic Background Retinopathy
63
(No Transcript)
64
(No Transcript)