بسم الله الرحمن الرحيم. Orbital region (I) Eyelids, lacrimal apparatus and...
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Transcript of بسم الله الرحمن الرحيم. Orbital region (I) Eyelids, lacrimal apparatus and...
الرحيم الرحمن الله بسم
Orbital region (I) ,Eyelidslacrimal apparatus
andorbital muscles
Orbital region (I) Eyelids, lacrimal apparatus
and orbital muscles
College of medicine in Al-AhsaCollege of medicine in Al-Ahsa
King Faisal UniversityKing Faisal University
Dr. Mohammad Bahgat(1431 – 1432 H)
Dr. Mohammad Bahgat (1431 – 1432 H)
ObjectivesBy the end of this lecture, you are expected to:
1- Know the anatomical features of the eyelids.
2- Know the anatomical features of the lacrimal apparatus.
3- Know the anatomical features of the orbital muscles.
4- Use anatomical knowledge to understand and explain
clinical features resulting from
paralysis of the orbital muscles.
Dr. Bahgat
lacus lacrimalisLateral angle
Medial angle
Palpebral fissure
Eyelids The eyelids are placed in front of the eyes to protect them from injury and excessive light. When the eye is opened, the space between the eyelids is called the palpebral fissure. The eyelids meet each other at the medial and lateral angles. The lateral angle of the palpebral fissure is acute and lies in contact with the eyeball. The medial angle is more rounded and is separated from the eyeball by a small space called lacus lacrimalis. The upper eyelid is larger and more mobile than the lower eyelid.
The upper eyelid covers the cornea completely when the eye is closed, and covers its upper margin when the eye is opened.
The lower eyelid lies below the cornea when the eye is opened and
rises only slightly when the eye is closed.
Dr. BahgatConjunctiva3 -Tarsus
2 -Orbicularis oculi muscle
1 -SkinLayers of the eyelid
Dr. Bahgat
Sagittal section of the upper eyelid
I- Skin
II- Orbicularis oculi M
III- TarsusVI- Conjunctiva
Anterior Posterior
The subtarsal sulcus
Layers of the eyelid
Dr. Bahgat
Sagittal section of the upper eyelid
The glands related to the eyelids
1- Sebaceous glands (of Zeis):
open into
the eyelash follicles.
Dr. Bahgat
2 -Ciliary glands (of Moll):
modified sweat glands
open between
the eyelashes.
The glands related to the eyelids
Dr. Bahgat
modified sebaceous glands
They open onto
the eyelashes
Tarsal glands
The glands related to the eyelids
Their secretion prevents
the overflow of tears and
makes the closed eyelids airtight.
that pour their oily secretion onto
the margin of the lid.
The lid margin
behind
Eyelids - The eyelids consist of the following layers from superficial to deep aspect: 1- Skin. 2- Orbicularis oculi muscle. 3- Tarsus. 4- Conjunctiva. - The eyelashes are present on the free edge and arranged in double or triple rows at the mucocutaneous junction. - The glands related to the eyelids are: 1- Sebaceous glands (of Zeis): open into the eyelash follicles. 2- Ciliary glands (of Moll): modified sweat glands open between the eyelashes. 3- Tarsal glands: modified sebaceous glands that pour their oily secretion onto the margin of the lid. They open behind the eyelashes. Their secretion prevents the overflow of tears and makes the closed eyelids airtight.
Dr. Bahgat
The superior tarsal plate The tarsi are dense fibrous plates
The lateral ends of the tarsal plates
are attached by
the lateral palpebral ligament
to a bonny tubercle just within the orbital margin
The medial ends of the tarsal plates
the medial palpebral ligament
to the anterior lacrimal crest (frontal process of the maxilla).
The inferior tarsal plate
are attached by
connected to
The aponeurosis of
pierces the orbital septum to reach
the anterior surface of the superior tarsal plate
The tarsal plates
the orbital margin by
the levator palpebrae superioris
fibrous orbital septa the lacrimal sac
Tarsi and palpebral ligaments
- The tarsi are dense fibrous plates connected to the orbital margin by fibrous orbital septum. - The lateral ends of the tarsal plates are attached by the lateral palpebral ligament to a bonny tubercle just within the orbital margin.
- The medial ends of the tarsal plates are attached by the medial palpebral ligament to the anterior lacrimal crest (frontal process of the maxilla).
- The tarsal glands are embedded in the posterior surface of the tarsal plates. - The outer surface of the orbital septum and tarsal plates are covered by
the palpebral fibers of the orbicularis occuli muscle. - The aponeurosis of the levator palpebrae superioris pierces the orbital septum to reach the anterior surface of the superior tarsal plate.
Dr. Bahgat
Sagittal section of the upper eyelid
VI- Conjunctiva
Anterior
Posterior
It is reflected from the eyelid
To form The fornix
The conjunctival sac
to the eyeball
is a thin mucous membrane
that lines the inner surface of the eyelids.
Its epithelium is continuous with
the corneal epithelium.
The subtarsal sulcus
Dr. Bahgat
Sagittal section of the eye & eyelids
Anterior
Posterior
The conjunctival sac
Palpebral Conjunctiva
is reflected from the eyelid
to the eyeball to form
Bulbar Conjunctiva
The angles between
Palpebral Conjunctiva
And Bulbar Conjunctiva
form Superior fornix
and inferior fornix
Its epithelium is continuous with
the corneal epithelium.
Dr. Bahgat
Sagittal section of the upper eyelid
The conjunctival sac
The conjunctiva thus forms
a potential space called
the conjunctival sac
This sac is closed
when the eye is closed
and it opens through
the palpebral fissure
when the eye is opened
Dr. Bahgat
Sagittal section of the upper eyelid
The subtarsal sulcus
This sulcus traps small foreign particles
that may enter the conjunctival sac
So it is clinically important
is a groove on the inner surface of the eyelid
parallel and close to
the lid margin
Conjunctiva - The conjunctiva is a thin mucous membrane that lines the inner surface of the eyelids.It is reflected onto the eyeball at the superior and inferior fornices. Its epithelium is continuous with the corneal epithelium. - The conjunctiva thus forms a potential space called the conjunctival sac. This sac is closed when the eye is closed, and it opens through the palpebral fissure when the eye is opened. - The subtarsal sulcus is a groove on the inner surface of the eyelid parallel and close to the lid margin. This sulcus traps small foreign particles that may enter the conjunctival sac
and is thus clinically important.
Dr. Bahgat
lacus lacrimalis
lacrimal caruncle
plica semilunaris
lacrimal papilla
lacrimal punctum
leading to
lacrimal canaliculus
Lateral angle
Medial angle
The conjunctival sac
The conjunctival sac - At the medial angle of the palpebral fissure,
there is a depression called lacus lacrimalis. The lacus lacrimalis contains
a small reddish yellow elevation called lacrimal caruncle
and a reddish semilunar fold called plica semilunaris lying
on the lateral side of the caruncle.
- Near the medial end of the margin of the eyelid,
there is a small elevation called lacrimal papilla.
- On the summit of the papilla,
there is a small hole called lacrimal punctum leading to
a small canal called lacrimal canaliculus.
This canaliculus carries the tears into the lacrimal sac
Dr. Bahgat
Lacrimal apparatus
Lacrimal gland
Lacrimal punctum
lacrimal canaliculus
the lacrimal sac
Nasolacrimal duct
Dr. Bahgat
Lacrimal gland
secretes tears into
the superior fornix
Tears collect in
the lacus lacrimalis
and enter
the lacrimal canaliculi
through the puncta
Canaliculi drain into
the lacrimal sac
Nasolacrimal duct
drains tears into
The inferior meatus of the nasal cavity
Lacrimal apparatus (flow of tears)
Dr. Bahgat
Flow of Tears
12
3 4
57
8
9
1- Lacrimal gland
2 -Excretory ducts
3 -Surface of eye
4 -lacus lacrimalis
5 -Lacrimal punctum
6 -Lacrimal canaliculus
7 -Lacrimal sac
8- Nasolacrimal duct
9 -Nasal cavity
6
Lacrimal apparatus This system consists of: I- Lacrimal gland.I- The lacrimal gland: It lies in the anterolateral part of the roof of the orbit above the eyeball. It consists of large orbital part (superior)
and small palpebral part (inferior) continuous together around the lateral margin of the aponeurosis of the levator palpebrae superioris muscle.The gland has about 8 - 12 ducts. These ducts open into the upper lateral part of the conjunctival sac.II- Lacrimal ducts: 1- Puncta lacrimalia. 2- Lacrimal canaliculi. 3- Lacrimal sac. 4- Nasolacrimal duct.
Lacrimal fluid - The lacrimal gland secretes tears into the conjunctival sac. - The tears circulate across the cornea and accumulate in the lacus lacrimalis.
From here the tears enter the lacrimal canaliculi through the puncta lacrimalia.
-The lacrimal canaliculi pass medially and open into the lacrimal sac. - The lacrimal sac lies in the lacrimal groove
(in the anterior part of the medial wall of the orbit) behind
the medial palpebral ligament. - The lacrimal sac is continuous below with the nasolacrimal duct.
This duct is 0.5 inch long and descends downward, backward and laterally in an osseous canal and opens into the anterior part of the inferior meatus of the nose. This opening is guarded by a fold of mucous membrane known as lacrimal fold. It prevents air from being forced up into the lacrimal sac on blowing the nose.
Parasympathetic supply of the lacrimal gland
Preganglionic fibers the lacrimatory nucleus in the pons
The facial nerve The greater petrosal nerve Unites with
The deep petrosal nerve To form The nerve of pterygoid canal
the pterygopalatine ganglionThen pass to
postganglionic fibers
the maxillary nerve
zygomatic nerve
zygomaticotemporal nerve
Then communication to
lacimal nerve
to reach
the lacrimal gland.
pass to
Dr. Bahgat
Nerve supply of the lacrimal gland
postganglionic fibers
the maxillary nerve
zygomatic nerve
zygomaticotemporal nerve
Then communication to
to reach
the lacrimal gland.
The lacimal nerve
Dr. Bahgat
Lacrimal nerve
Zygomatic nerve
Zygomaticotem
poralNerve supply of the lacrimal gland
Then communication to
postganglionic fibers
Lacrimal gland to reach
Lacrimal apparatusIts parasympathetic supply is derived from
the lacrimal nucleus of the facial nerve (in the pons).
The preganglionic fibers pass along the facial nerve ------- greater petrosal nerve ----------
nerve of pterygoid canal to reach the --------
pterygopalatine ganglion.
The postganglionic fibers
pass along the maxillary nerve ------ zygomatic nerve -------------- ------- zygomaticotemporal nerve ----- then lacimal nerve to reach
the lacrimal gland.
Orbital muscles
Dr. Bahgat
Walls of the OrbitRoof
lateral medial
orbital plate of frontal bone
Lateral wall
lesser wing of sphenoid
Zygomatic bone
Medial wall
greater wing of sphenoid
frontal process of the maxilla lacrimal bone
orbital plate of ethmoid bone
Floor
body of the sphenoid
orbital plate of maxilla Zygomatic bone
Orbital process of palatine bone
Dr. Bahgat
Features of the Orbit
lateral medial
Roof
Lacrimal fossa
Optic canal
Medial wall
Lacrimal groove Anterior ethmoid foramen Posterior ethmoid foramen
Floor Infraorbital groove Infraorbital canal Infraorbital foramen
Superior orbital fissure
Roof
Lateral wall
Inferior orbital fissure
Floor
Dr. Bahgat
The Orbital muscles
2 oblique muscles
The orbital muscles are Levator palpebrae superioris
The 4 recti muscles
superior rectus
inferior rectus
medial rectus
lateral rectus
superior oblique
inferior oblique
medial
lateral
Muscles of the orbitThe orbital muscles are:
1- Levator palpebrae superioris.
2- 4 recti muscles: - superior rectus
- inferior rectus
- medial rectus
- lateral rectus
3- 2 oblique muscles: - superior oblique
- inferior oblique
Dr. Bahgat
Orbital muscles (origin)
The 4 recti muscles
Originate from
the common tendinous ring
Superior Rectus
Medial Rectus
Inferior Rectus
Lateral Rectus (2 heads)
Levator palpebrae superioris
Originates from
From the lower surface of
the lesser wing of sphenoid bone
(posterior part of the roof of the orbit).
Inferior Oblique Originates from
From the anteromedial part of the floor of the orbit
lateral medial
Dr. Bahgat
Orbital muscles (origin)
The 4 recti muscles
Originates from
The common tendinous ring
Originates from
the anteromedial part of the floor of the orbit
Originates from
The body of the sphenoid bone
The superior oblique
The inferior oblique
Dr. Bahgat
Orbital muscles (insertion)
The recti muscles Are inserted into
In front of the equator of the eyeball
The oblique muscles Are inserted into
behind the equator of the eyeball
Levator palpebrae superioris
the sclera
the sclera
Nerve supplyMuscle
Lateral Rectus*
Superior Rectus
Medial Rectus
Inferior Rectus
Inferior Oblique
Superior Oblique*
Nerve supply
CN VI – Abducent
CN III
CN IV - Trochlear
Oculomotor
CN III Levator palpebrae superioris
Inferior division
OculomotorSuperior division
Levator palpebrae superioris
Dr. Bahgat
Cut end (origin)
Cut end (insertion)
)dilator(
Levator palpebrae superioris
Levator palpebrae superioris m. Orbital Roof is removed (seen from above)
Superior rectus
Superior oblique
Dr. Bahgat
Levator palpebrae superioris m.
Dr. Bahgat
Levator palpebrae superioris muscle (origin)
Levator palpebrae superioris Originates from
the lower surface of the lesser wing of sphenoid bone
(posterior part of the roof of the orbit).
lateral medial
Dr. Bahgat
Levator palpebrae superioris Is inserted into
The superior tarsal plate
Dr. Bahgat
Its tendon forms a wide aponeurosis
which splits into two lamellae
The superior lamella
contains striated muscle fibers
To be inserted into
the anterior surface
of the superior tarsal plate
and the skin of the upper eyelid
The inferior lamella
contains smooth muscle fibers
It is inserted into
the upper border of the superior tarsal plate
It pierces the orbital septum
Levator palpebrae superioris muscle (insertion)
Dr. Bahgat
Levator palpebrae superioris muscle (nerve supply)
Nerve supply: Superior lamella by
superior division of
oculomotor nerve
Inferior lamella by
sympathetic fibers derived from
the superior cervical sympathetic ganglion.
Dr. Bahgat
Sagittal section of the eyeAponeurosis of
Levator palpebrae superioris
Action:
Elevation of the upper eyelid
sympathetic stimulation results in
further elevation of the upper eyelid
To open
the palpebral fissure
Levator palpebrae superioris Origin: From the lower surface of the lesser wing of sphenoid bone (posterior part of the roof of the orbit).
Insertion: - Its tendon forms a wide aponeurosis which splits into two lamellae.
- The superior lamella:
(contains striated muscle fibers) is inserted into the anterior surface of the superior tarsal plate and the skin of the upper eyelid.
- The inferior lamella: contains smooth muscle fibers. It is inserted into the upper border of the superior tarsal plate.
Nerve supply:
Superior lamella by superior division of oculomotor nerve.
Inferior lamella by sympathetic fibers derived from the superior cervical
sympathetic ganglion.
Action: - Elevation of the upper eyelid. - sympathetic stimulation results in further elevation of the upper eyelid. - Injury of oculomotor nerve or sympathetic supply leads to dropping of the upper eyelid
(ptosis).
Recti muscles
Dr. Bahgat
Recti muscles (origin)
The 4 recti muscles Originate from
the common tendinous ring
Superior Rectus
Medial Rectus
Inferior Rectus
Lateral Rectus (2 heads)
lateral medial
Dr. Bahgat
Recti muscles (insertion)
The recti muscles Are inserted into
In front of the equator of the eyeball
the sclera
Dr. Bahgat
Nerve supply of recti muscles
superior rectus
Superior division of oculomotor
Medial rectus
inferior division of oculomotorInferior rectus
inferior division of oculomotor
Dr. Bahgat
Nerve supply of recti muscles
superior rectus
Superior division of
Medial rectus
inferior division ofInferior rectus
inferior division of
oculomotor nerve
Dr. Bahgat
lateral rectus Abducent nerve
Nerve supply of recti muscles
The 4 recti muscles Origin: - They arise from a fibrous ring called
the common tendinous ring. - This rig is a thickening in the periosteum. It surrounds the optic canal and bridges the superior orbital
fissure. - Each rectus muscle arises from a part of the ring corresponding to its name: Superior rectus ---- upper part. Inferior rectus ----- lower part. Medial rectus ------- medial part. Lateral rectus ------ by two heads from the lateral part of the ring.
Insertion: - Each muscle pierces the fascial sheath of the eyeball to be inserted into the sclera about 6 mm behind the corneoscleral junction In front of the equator of the eyeball.
Nerve supply: - The lateral rectus by the abducent nerve.
- The other 3 recti by oculomotor nerve. superior rectus (superior division) medial and inferior recti (inferior division)
Action: - lateral rectus moves the eye laterally. - Medial rectus moves the eye medially. - Superior rectus: moves the eye upward and medially. - Inferior rectus: moves the eye downward and medially.
Oblique muscles
Dr. Bahgat
superior oblique
Inferior oblique
Trochlea
Oblique muscles
lateral view
Dr. Bahgat
superior oblique
Oblique muscles Superior view
Dr. Bahgat
Inferior oblique
Oblique muscles Anterior view
Dr. Bahgat
Oblique muscles (origin)
Superior oblique Originates from
body of the sphenoid bone
Inferior Oblique Originates from
the anteromedial part of the floor of the orbit
lateral medial
Posterior part of
the medial wall of the orbit
at its junction with the roof
Dr. Bahgat
Oblique muscles
The oblique muscles Are inserted into
behind the equator of the eyeball
the sclera
Oblique muscles (insertion) lateral view
Dr. Bahgat
Inferior obliqueAre inserted into the sclera behind
the equator of the eyeball.
&Superior oblique
Superior view
Lateral view
Dr. Bahgat
superior oblique
Nerve supply of oblique muscles
Is supplied by
Trochlear nerve
lateral view
Dr. Bahgat
Nerve supply of oblique muscles
Inferior oblique
Is supplied by
inferior division of
oculomotor nerve
lateral view
The 2 oblique muscles I- Superior oblique: Origin: From the body of the sphenoid bone.
Insertion: - Its rounded belly passes forward and forms a slender tendon which rotates around the trochlea (fibrocartilaginous bulley). - Then the tendon passes downward, backward and
laterally below the superior rectus muscle.
and pierces the fascial sheath of the eyeball to be inserted into the sclera behind the equator of the
eyeball.
Nerve supply: - by the trochlear
nerve.
Action: - It moves the eyeball
downward and laterally.
The 2 oblique muscles II- Inferior oblique: Origin: - From the anterior part of the floor of the
orbit. Insertion: - It passes upward, backward and laterally below the inferior rectus and
pierces the fascial sheah of the eyeball to be inserted into the sclera behind the equator of the eyeball.
Nerve supply: - by the oculomotor nerve (inferior division).
Action: - It moves the eyeball upward and laterally.
Movement of the eyeball around different axes
Dr. Bahgat
elevation
depression
Movement around the axes
Transverse axis
Transverse axis
Dr. Bahgat Adduction
Abduction
Movement around the axes
Vertical axis
Dr. BahgatIntorsion
Extorsion
Movement around the axes
Visual axis(Anteroposterior)
Action of
Individual orbital muscles
Dr. Bahgat
medial rectus
lateral rectus
Adduction
Abduction
Dr. Bahgat
superior rectus inferior rectus
Elevation & adduction
Depression & adduction
Dr. Bahgat
superior oblique
inferior obliqueDepression & abduction
Elevation & abduction
lateral rectusmedial rectusinferior rectussuperior obliquesuperior rectusinferior oblique
Looking lateralLooking medialLooking down medialLooking down lateral Looking up medial Looking up lateral
Action of individual muscles
Left lateral rectusRight medial rectus Left medial rectusRight lateral rectus Left inferior rectus & Left superior oblique
Right inferior rectus & Right superior oblique
Left superior rectus & Left inferior oblique
Right superior rectus & Right inferior oblique
Left inferior rectusRight superior obliqueLeft superior obliqueRight inferior rectus Left superior rectusRight inferior obliqueRight superior rectus Left inferior oblique
Looking to left sideLooking to right side Looking downward Looking upward Looking down & rightLooking down & left Looking up & right Looking up & left
Conjugate movement of the two eyes
Dr. Bahgat
M.R.L.R. 1
To right side
L.R.M.R.2
To left side
Both S.R. + I.O.
3 upward
Both I.R.+ S.O.
4 downward
S.R I.O.5
Up & left side
S.R.I.O.6
Up & right side
I.R. S.O.7
Down & left side
S.O. I.R.8
down & right side
Looking to right side Left medial rectusRight lateral rectus Looking to left side Left lateral rectus Right medial rectus Looking upward Left superior rectus & Left inferior oblique
Right superior rectus & Right inferior oblique
Looking downward Left inferior rectus & Left superior oblique
Right inferio rectus & Right r superiorobliqueRight superior rectus Left inferior oblique Looking up & left Left superior rectusRight inferior oblique Looking up & right Left inferior rectusRight superior oblique Looking down & right Left superior obliqueRight inferior rectus Looking down & left
Conjugate movement of the two eyes
Dr. Bahgat
What is this?
Dr. BahgatDr. Bahgat
Case 1 Patient: survived a posterior cerebral aneurysm
ptosis
dilated pupil
left eye is
Conclusion lesion of the oculomotor nerve (CN III) Why?
directed downward
and abducted.
wrinkled forehead
Signs:
Symptoms:
double vision
cannot accommodate
Dr. Bahgat
Case 2 What is the patient’s problem?
Medial Strabismus
Caused by paralysis of lateral rectus
Results in diplopiaResults in diplopia
right eye is directed
Medially (i.e. adducted).
What is the diagnosis
Case 1 Case 2
Dr. Bahgat
What is this?
What is this?
Testing Extraocular Movements
In the setting of an eye movement problem, it can help to check movement in the direction in which
that muscle is the primary mover. This can be assessed as follows: Superior oblique:
Depresses the eye when looking medially Inferior oblique:
Elevates the eye when looking medially Superior rectus:
Elevates the eye when looking laterally Inferior rectus:
Depresses the eye when looking laterally Medial rectus:
Adduction when moving the eye along horizontal plane Lateral rectus:
Abduction when moving the eye along horizontal plane
Testing individual muscles
References
Last’s anatomy Regional and applied )R.M.H. McMinn – (9th edition
Clinical anatomy (Richard S. Snell) – 7th edition
Grey’s anatomy – 39th edition
Good luck
Testing Extraocular Movements
Practically speaking, cranial nerve testing is done such that the examiner can observe eye movements in all directions. The movements should be smooth and coordinated. To assess, proceed as follows:
Stand in front of the patient. Ask them to follow your finger with their eyes while keeping
their head in one position Using your finger, trace an imaginary "H" or rectangular
shape in front of them, making sure that your finger moves far enough out and up so that you're able to see all appropriate eye movements (ie lateral and up, lateral down, medial down, medial up).
At the end, bring your finger directly in towards the patient's nose. This will cause the patient to look cross-eyed and the pupils should constrict, a response referred to as accommodation.