Download Topography

September 2013
Introduction to ophthalmology
Topography of the eye, 3D tour.
Dr.Ali.A.Taqi
Fifth year students.
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Topography
• Topography is the study of the gross surface relationships
between different aspects of the surface of a structure or
between various objects related to that structure.
• The globe is a highly complex object both in terms of its
own three-dimensional shape and because of the number of
other anatomic elements contained within it and
surrounding it.
• In addition, a number of vascular and neural structures
pass into and out of the globe, further complicating its
topography.
• However, to adequately understand the globe as an organ
of vision, it is first essential to understand its structure and
the complex interrelationships that exist between its
internal organization and the external elements surrounding
it.
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• 1=the pupil
2=the iris
3=sclera covered by the
conjunctiva
4=eyelid margin &eyelashes
5= upper eyelid
6=lateral canthus
7=medial canthus
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The eye ball & the orbit.
• The globe is positioned in the anterior portion of
the orbit and constitutes about 20% of the entire
volume of the orbit.
• It is slightly closer to the lateral orbital wall than
the medial wall and is nearer the roof than the
floor of the orbit.
• At its closest distance to the bony orbit the globe
is about 4 mm from the roof, 4.5 mm from the
lateral wall, 6.5 mm from the medial wall, and
6.8 mm from the floor.
• The lateral orbital rim is considerably recessed
compared with the medial orbit, which continues
anteriorly to end at the nasal bridge. This leaves
approximately one half of the globe unprotected.
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The bony orbit.
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Blood supply
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Superior orbital fissure
&optic foramen
• OF=optic foramen.
• SOF=superior orbital
fissure.
• IOF=inferior orbital
fissure.
• IV=trochlear nerve
• III=third cranial nerve
• VI=sixth cranial nerve
(the abducent)
• L=lacrimal nerve
• F=frontal nerve.
• N=nasocillary nerve
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Nerve supply
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Extraocular muscles
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Quiz!!!!
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Quiz!!!
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Quiz!!!
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what are the abnormalities
seen bellow?
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