This document describes the anatomy and pathways of the visual system. It discusses the optic nerve, optic chiasm, optic tract, lateral geniculate nucleus, optic radiations, and visual cortex. It notes the intraocular, intraorbital, intracanalicular, and intracranial segments of the optic nerve. It describes the structures that the optic tract and optic radiations connect and the areas of the visual cortex responsible for different parts of the visual field. Diagrams illustrate the visual fields and pathways. Lesions in different parts of the visual system can cause different types of visual field defects.

1. Optik Sinir ve Görme Yolları
Hacettepe Üniversitesi Tıp Fakültesi
Nöroşirurji Anabilim Dalı
Araştırma Görevlisi M.Enes Gürses

4. -Optic Nerve
-Optic Chiasma
-Optic Tract
-Lateral Geniculate Body
-Optic Radiations
-Visual cortex

7. Optic nerve:
- Intraocular (1 mm)
- Intraorbital (30 mm)
- Intracanalicular (6-9 mm)
- Intracranial (10 mm)

13. Optik Kiazma
-12 mm/horizontal
- 8mm/anteroposterior

20. 20
.
OT
ON
OC
VISUAL
CORTEX
RETINA
VISUAL
FIELD
LGN
OPTIC
RADIATIONS
ON = Optic Nerve
OC = Optic Chiasm
OT = Optic Tract
LGN = Lateral Geniculate Nucleus of
Thalamus

21. 21

22. 22
Görme Alanı
Normal Binocular Visual Field
F
Right Visual FieldLeft Visual Field
Upper Fields
Lower Fields
Temporal Field of
Left Eye
Nasal Field of
Left Eye
Normal Monocular Visual
Field of Left Eye
F F
Normal Monocular Visual
Field of Right Eye
Monocular
Crescent of
Right Eye
Monocular
Crescent of
Left Eye

23. 23
• Optik Sinir
• Diencephalondan gelişir.
• Miyelinizasyonu oligodendrositlerden
olur.
• Optik Kiazma
Left visual field Right visual field
Right retinaLeft retina
Left LGN
Tempora
l
Nasal Tempora
l
Nasal
lateral lateralmedial medial
LVFLVF UVFUVF
E.W.
Right visual
cortex
midbrain
Right LGN
Left visual cortex
Left
temporal
retina
Right
temporal
retina
Nasal
retina
Ciliary
ganglion
pretectal
nuclei
cuneus
lingual
gyrus
Calcarin
e sulcus
III
III
Upper field
Lower field
VISUAL FIELDS:
Hatched = binocular
Stippled = monocular
Central area = macula
ON
OC
OT
Görme Yolu

24. 24
• Optik Trakt (OT)
• Optik kiazmadan lateral geniculat nukleusa
kadar olan parça.
• Optik traktlar karşı tarafın görme alanıyla
ilgili kısmı taşır.
Left visual field Right visual field
Right retinaLeft retina
Left LGN
Tempora
l
Nasal Tempora
l
Nasal
lateral lateralmedial medial
LVFLVF UVFUVF
E.W.
Right visual
cortex
midbrain
Right LGN
Left visual cortex
Left
temporal
retina
Right
temporal
retina
Nasal
retina
Ciliary
ganglion
pretectal
nuclei
cuneus
lingual
gyrus
III
III
Post kiazmatik bölüm: Upper field
Lower field
VISUAL FIELDS:
Hatched = binocular
Stippled = monocular
Central area = macula
ON
OC
OT
• Lateral Geniculate Nucleus (LGN)
• Kontralateral görme alanından sorumlu.
Görme Yolu

25. 25
• Geniculocalcarine Trakt (= optik
radiation)
• LGN aksonları primar visual cortex (Area
17)’e uzanıyor.
• Temporal lobe - Meyer’s loop
Left visual field Right visual field
Right retinaLeft retina
Left LGN
Tempora
l
Nasal Tempora
l
Nasal
lateral lateralmedial medial
LVFLVF UVFUVF
E.W.
Right visual
cortex
midbrain
Right LGN
Left visual cortex
Left
temporal
retina
Right
temporal
retina
Nasal
retina
Ciliary
ganglion
pretectal
nuclei
cuneus
lingual
gyrus
Calcarin
e sulcus
III
III
Meyer’s
loop
Optic radiation or
geniculocalcarine
tract
Upper field
Lower field
VISUAL FIELDS:
Hatched = binocular
Stippled = monocular
Central area = macula
ON
OC
OT
Görme Alanı

26. 26
Left visual field Right visual field
Right retinaLeft retina
Left LGN
Tempora
l
Nasal Tempora
l
Nasal
lateral lateralmedial medial
LVFLVF UVFUVF
E.W.
Right visual
cortex
midbrain
Right LGN
Left visual cortex
Left
temporal
retina
Right
temporal
retina
Nasal
retina
Ciliary
ganglion
pretectal
nuclei
cuneus
lingual
gyrus
Calcarin
e sulcus
III
III
Meyer’s
loop
Optic radiation or
geniculocalcarine
tract
Upper field
Lower field
VISUAL FIELDS:
Hatched = binocular
Stippled = monocular
Central area = macula
ON
OC
OT
• Primary Visual Korteksi ( 17. Bölge)
• Calcarine fissure.
• Üst lifler-lingual gyrus.
• Alt lifler-cuneus.
• Asosiasyon Görme Korteksi ( 18
& 19. Bölge)
Görme Yolu

27. makulanın korunması=macular sparing görmeyen yarı alanda makulaya uyan santral bir
bölgede vizyonun sağlam kalmasıdır.
Corpus geniculatum laterale’nin arkasındaki lezyonlarda hemianopik alanda maküler vizyon
bozulmamıştır. Tractus opticus hastalığında ise maküler alan da dahildir.

28. 28
Lesions of the Visual Pathway
1. Normal visual fields
2. Blindness of the right eye
3. Blindness of right eye + contralateral left upper
quadrantanopia
4. Bitemporal heteronymous hemianopsia
5. Left homonymous hemianopsia
6. Left upper homonymous quadrantanopsia
7. Left homonymous hemianopsia with macular
sparing
RightLeft
Pg. 6

33. Teşekkürler…
• Kaynaklar:
• Rhoton Cranial Anatomy and Surgical Approaches
• Washington University: The Basic Visual Pathway
• http://thalamus.wustl.edu/course/basvis.html
• Netter: Plates 86 and 114
• Greenberg Handbook of Neurosurgery
• TND Temel Nöroşirurji 2010