Orbit And Its Contents Flashcards
The bones of the orbit is a _______ shaped cavity
pyramidal shaped
The bones of the orbit has the following BOUNDARIES:
An Apex, a Base and 4 Margins + 4 walls (Orbital Roof, Medial and Lateral Orbital Wall, Orbital Floor)
NB:
Apex = optic canal
Base = orbital margins
Has 4 margins + 4 walls
The Apex of the bones of the orbit is formed by the?
OPTIC CANAL
The Base of the bones of the orbit is formed by the?
ORBITAL MARGINS
The Margin of the bones of the orbit include:
- Superior:
Mnemonic: Superior - F - Inferior:
Mnemonic: Inferior - ZM - Medial:
Mnemonic: Medial - FM - Lateral:
Mnemonic: Lateral - ZF
- Superior – frontal bone
- Inferior – zygomatic and maxillary bones
- Medial – frontal and maxillary bones
- Lateral – zygomatic and frontal bones
ORBITAL ROOF IS FORMED BY:
- Orbital plate of the frontal bone
+
The lesser wing of the sphenoid bone (posterior part) - Lacrimal gland
- Fovea trochlearis
The two bones that form the orbital roof are?
- Orbital plate of the frontal bone
+ - The lesser wing of the sphenoid bone (posterior part)
Medial Orbital Wall IS FORMED BY :
NB: it is 5cm long
- Is formed from four bones:
( Frontal process of the maxillary bone, Lacrimal bone, Orbital plate of the ethmoidal bone, Body of the sphenoid) - Lacrimal Fossa
- Anterior and posterior ethmoidal foramina
The four bones that forms the Medial Orbit wall include:
- Frontal process of the maxillary bone.
- Lacrimal bone.
- Orbital plate of the ethmoidal bone.
- Body of the sphenoid
The four bones that forms the Medial Orbiat wall include:
- Frontal process of the ________ bone.
- La____al bone.
- Orbital plate of the eth___al bone.
- Body of the sp____id
- maxillary Bone
- . Lacrimal Bone
- ethmoidal Bone
- sphenoid Bone
The two bones that form the orbital roof are?
- Orbital plate of the fr__al bone
+ - The lesser wing of the sphe___d bone (posterior part)
- frontal bone
2. sphenoid bone
Anterior and posterior ethmoidal foramina
1. Anterior ethmoidal = __mm behind __________ crest
Posterior = ___ mm behind the ante. Ethmoidal foramen
- 24 mm, anterior lacrimal
2. 12mm, anteerior Ethmoidal
The Orbital Floor is formed by:
- The floor of the orbit is formed from three bones:
(Maxillary, Palatine ,Orbital plate of the zygomatic bone) - Infraorbital groove
- Inferior oblique muscle
The floor of the orbit is formed from three bones:
- Maxillary
- Palatine
- Orbital plate of the zygomatic
The floor of the orbit is formed from three bones:
- Ma___ary
- Pal__ne
- Orbital plate of the zy___matic
- Maxillary
- Palatine
- Orbital plate of the zygomatic
Lateral Orbital Wall IS FORMED BY :
NB: It is the Thickest and strongest
5cm; perpendicular to each other
- Formed from two bones:
Zygomatic
Greater wing of the sphenoid - Lateral orbital tubercle (Whitnall’s tubercle)
Lateral Orbital Wall IS FORMED BY 2 Bones :
- Zy___atic Bone
- Greater wing of the sphe__d Bone
- Zygomatic Bone
2. Greater wing of the sphenoid
Lateral Orbital Wall IS FORMED BY 2 Bones :
- Zygomatic Bone
2. Greater wing of the sphenoid
The Orbital Foramina Include:
- The optic foramen (Optic Nerve)
- The supraorbital foramen, or notch (Supra-orbital nerve
and blood vessels) - The Anterior and Posterior ethmoidal foramen (Anterior and Posterior Ethmoidal Nerves)
- The zygomatic foramen ( ZygomaticoFacial and temporal)
- Nasolacrimal canal (Nasolacrimal duct)
- Infra-orbital canal
7. Superior orbital fissure (Lacrimal nerve- Ophtalmic nerve branch, Frontal nerve - Ophtalmic nerve branch, Nasociliary nerve - Ophtalmic nerve branch, Trochlear nerve , Oculomotor nerve, Abducent nerve, Superior ophthalmic vein) 8. Inferior Orbital fissure
The Orbital Foramina Include:
- The _____ foramen (Optic Nerve)
- The _________ foramen, or notch (Supra-orbital nerve
and blood vessels) - The Anterior and Posterior ________ foramen (Anterior and Posterior Ethmoidal Nerves)
- The _________ foramen ( ZygomaticoFacial and temporal)
- _________ canal (Nasolacrimal duct)
- -__________ canal
7. Superior \_\_\_\_\_\_\_\_ fissure (Lacrimal nerve- Ophtalmic nerve branch, Frontal nerve - Ophtalmic nerve branch, Nasociliary nerve - Ophtalmic nerve branch, Trochlear nerve , Oculomotor nerve, Abducent nerve, Superior ophthalmic vein)
- Inferior _______ fissure
- optic
- supraorbital
- ethmoidal
- zygomatic
- Nasolacrimal
- Infra-orbital
- orbital
- orbital
Vessels of the orbit are:
1.
3.
- Ophthalmic artery,
- Superior & inferior ophthalmic veins
- lymphatics
Vessels of the orbit are:
- Op___almic artery,
- Superior & inferior Op___almic veins
- l____atics
- Ophthalmic
- ophthalmic
3 lymphatics
Ophthalmic artery branches include:
6.
- central artery of the retina
- Muscular branch
- ciliary arteries
- supra-trochlear arteries
- supra-orbital arteries
- lacrimal arteries
Ophthalmic artery branches include:
- c___al artery of the retina
- M____ar branch
- cil__y arteries
- supra-tr___ear arteries
- supra-o___l arteries
- l____al arteries
- central
- Muscular
- ciliary
- trochlear
- orbital
- lacrimal
Nerves that supply the orbit:
2.
4.
- Optic CN II
- Oculomotor CN III
- Trochlear CN IV
- Branches of Ophthalmic nerves CN V1 = Lacrimal + Frontal + Nasociliary