2. CONTENTS
Anatomy of Orbit –
Bony Orbit,
Floor, Medial wall, Lateral Wall, Roof ,Apex of Orbit
Classification of fracture
Pathophysiology of Fracture
Blow In fracture
Blow Out Fracture – Pathophysiology & Clinical features.
Superior Orbital Fissure Syndrome - Pathophysiology &
Clinical features.
CLINICAL EVALUATION – Forced Duction Test , Hess
Chart
Management –
Incisions – Subciliary , Transconjuctival
Orbital Floor Dissection & Reconstruction.
3. Anatomy of Orbit
Orbit – conical cavity
Base – Anteriorly
Apex – directed at Optic Foramen
Orbital Volume – 30cc ; Globe – 7cc
By Age 5 years orbital growth is 85% complete , Finalised
between 7 years of age
Bones – 7 (Maxillary, Zygomatic, Frontal, Ethmoid, Larimal,
Palatine, and Sphenoid )
Four Walls – roof, lateral, medial, floor
Medial wall & floor – thin ;
Lateral wall & Roof – Stronger.
Floor weakened – due to – Infraorbtal Canal passing through
it
4. Medial wall – Formed by – Lamina Papyracea of
Ethmoidal bone & Lacrimal
bone
Vital Contents – Eyeball (Non Compressible)
6 EXTRAOCULAR MUSCLES –
Originate from Common Tendinous fibrous ring
Annulus of Zinn – Fibrous ring – Common origin of 4
Rectus Muscle
OPTIC NERVE – direct extension of Gray Matter
Very sensitie to Compression and once damaged fails to
regenerate
SUPERIOR ORBITAL FISSURE
Transmits – 3rd , 4th & 6th Cranial Nerves
Opthalmic Division of 5th Cranial Nerve
5. Cranial Nerves and its Supply
Occulomotor (C.N.-III)- Supplies –
Superior Rectus
Medial Rectus
Inferior Rectus
Inferior Obliqus
Abducent Nerve – Lateral Rectus (LR6 )
Trochlear Nerve – Superior Obliqus (SO4)
6. Theoretically, the mechanical load of the orbital
floor is approximately 0.0005 N/mm2 (30 g orbital
content onto 600 mm2 of orbital floor area), as
indicated by several cadaver investigations.
7. CLASSIFICATION
ORBITAL WALL FRACTURES –
1. Blow Out Fracture
2. Pure Blow Out Fracture
3. Impure Blow Out Fracture
4. Blow In Fracture
ISOLATED ORBITAL WALL FRACTURE :
1. Roof
2. Floor
3. Medial wall
4. Lateral wall
8. ISOLATED FRACTURES OF THE ORBITAL RIM
:
1. SUPERIOR RIM
2. INFERIOR RIM
3. MEDIAL RIM
4. LATERAL RIM
COMPLEX COMMINUTED FRACTURES :
Nasoethmoidal and fronto-naso-orbital fractures
10. Floor Of Orbit
Extends – Rim to approx.
2/3rd of the depth of the orbit
Posteromedial aspect of
Orbital floor transitions into
Medial Orbital Wall – to form
– Posterior Medial Bulge
Only three of four orbital wall
extend into the Apex –
Medial, Superior , Lateral
Anterior third – Diameter
widens behind Superior
Inferior margins ‘Post Entry
Concavity’ – Saggital plane –
‘Lazy S’ shapePeterson’s Principles of Oral and Maxillofacial Surgery ; 2nd Edition ; Page –
11. Floor of Orbit
Surface Landmarks –
Infraorbital Groove – bony
sulcus
Inferior Orbital Fissure –
converts into canal –
continues to Infraorbital
Foramen
Origin Of Inferior Oblique
Muscle
Posterior Lateral
Promontry – Posterior
medial bulge ending in a
raised Promontory shaped
lateral plateau. Delineated –
junctional zone of –
14. MEDIAL WALL
Convex Rectangular
shape
Runs Parallel to
Saggital Plane
Medial wall – paper
thin Lamina paprycea
– (0.2-0.4mm)
Reinforced along the
Maxillary-Ethmoidal
suture --- forming an
Internal Orbital
Buttress.
Peterson’s Principles of Oral and Maxillofacial Surgery ; 2nd Edition ; Page –
15. Surface Landmarks –
Lacrimal Fossa – Anterior
1/3rd of the Medial Wall
Frontoethmoidal suture –
Roof of the ethmoid sinus at
the level of the cribriform
plate
Ant. & Post. Ethmoidal
Foramen – along
frontoethmoidal suture in
midorbit
Distances –
Medial orbital Rim – Ant.
Ethmoid Foramen – 22-
25mm
Post. Ethmoid Foramen to
Ant Ethmoid Foramen – 12-
15mmPeterson’s Principles of Oral and Maxillofacial Surgery ; 2nd Edition ; Page –
16. LATERAL WALL
Forms – Triangle with an anterior
base
Forms 45degree angle to its
medial wall counterpart
SURFACE LANDMARKS –
Whitnall’s tubercle – small bony
projection – actual insertion is
‘Common lateral retinaculum’.
Lateral horn of lateral aponeurosis
Lateral canthal tendon of eyelids
Inferior Suspensory (Lockwood’s)
Ligaments.
Multiple fine check ligaments of
Lateral Rectus Muscle.
Superior & Inferior Orbital
Fissure
Zygomaticosphenoid suture –
imp. Landmark to verify proper
reduction of complex ZMC
fracture.Peterson’s Principles of Oral and Maxillofacial Surgery ; 2nd Edition ; Page –
17. Roof Of Orbit
Domed contour
Comprised of – Orbital plate of
the Frontal Bone
Extremely thin
In Apex – Roof terminates into
Lesser Wing of Sphenoid –
where Oval shaped Optic
foramen forms Optic canal
SURFACE LANDMARKS:
Trochlear fossa : Zone of
attachment of tendon of
Superior Oblique muscle
Lacrimal Gland Fossa
Peterson’s Principles of Oral and Maxillofacial Surgery ; 2nd Edition ; Page.
18. Apex of Orbit
Posterior third – made by
sphenoid bone
Superior Orbital Fissure –
separates the Lesser wing
of sphenoid & Greater Wing
of Sphenoid
Optic Canal – within the
lesser wing of sphenoid
Annulus of Zinn – all
Extraocular muscles except
Inf. Oblique arises from this
tendinous ring
20. Limit of Dissection
Inferiorly(Floor) – Upto 28-30mm (safe limit) –
optic canal is at around 40mm
Laterally – Superior Orbital Fissure
Superiorly – Orbital roof dissection is stopped at
periorbital surrounding Recurrent Meningeal
Artery – passing through bony canal within the
Sphenofrontal suture line
Medially – Posterior extent – Posterior Ethmoidal
vessels , running in the Fronto-Ethmoidal Suture
line Anterior to Optic foramen.
21. Distance of Vital Orbital Structures
from Bony Landmarks
STRUCTURE REFERENCE
LANDMARK
MEAN DISTANCE (mm)
Midpoint of inferior
orbital fissure
Infraorbital foramen 24
Anterior Ethmoidal
Foramen
Anterior Lacrimal crest 24
Superior Orbital Fissure Zygomaticofrontal suture 35
Superior orbital Fissure Supraorbital Notch 40
Optic Canal (medial
aspect)
Anterior Lacrimal Crest 42
Optic Canal (Superior
Aspect)
Supraorbital notch 45
Peterson’s Principles of Oral and Maxillofacial Surgery ; 2nd Edition ; Page –
465
23. In the event of Trauma
Thick Rims protect the Eyeball
Absorb shock by Fracturing themselves
Orbital walls (especially Medial Wall & Floor) fracture
in an isolated way
Gets displaces Inwards or Outwards
Called as ‘Blow-In’ or ‘Blow-Out’ fractures
24. PURE Blow Out OR Blow In –
Orbital Walls fracture in Isolation
IMPURE Blow Out or Blow In Fracture –
Walls + Rim
26. Blow Out Fracture
Term coined by – Smith and Regan – 1957
First described by MacKenzie in Paris in 1844
PATHOPHYSIOLOGY
Buckling Theory –
This theory states that
- if a force was to strike any part of the orbital rim,
- it will cause walls to undergo a rippling effect & the
force striking the rim
- -will transfer to the weaker portion especially the floor
& cause them to distort & eventually fracture
27. Pathophysiology of blow out fracture
of the orbit
Hydraulic Theory (Pfeiffer in
1943) – he said that it is evident
that the force of the blow received
by the eyeball was transmitted by
it to the walls of the orbit with
fracture of the delicate portions.
- Therefore direct injury to the globe
forcing it into the orbit was
necessary.
Medial Wall & Floor –Thin &
Fragile
Fracture readily – provide natural
compensation
As they fracture – Orbital Size
28. Clinical Features
Circumorbital Edema -
Subconjunctival Bleeding – due to fracture
subperiosteal bleeding escapes in
subconjuctival plane.
Enopthalmous Increase in size of Orbit
Eyeball sinks
Periorbital Fat Herniates through fractured walls
‘Hanging-drop’ Appearance
Unilateral Epistaxis – bleeding into antrum
Numbness in area of distribution of Infraorbital
Nerve
Diplopia or Vertical gage – Inferior Rectus or
Inferior Obliqus gets entrapped in fracture
32. Pathophysiology
Raised Intraorbital Pressure (due to
Hematoma/Displaced fractured segments)
Compression of contents of Sup. Orbital Fissure
Paresis of Nerve
Neurological deficit in their distribution
33. Occulomotor supplies – SR , MR, IR , IO
Abducent – LR
Trochlear – SO
Due to paresis of these nerves all these
extraocular muscles undergo paralysis eyeball
fails to move ‘External Opthalmoplegia’
As affected eye does not move whereas
contralateral normal eyeball moves focal axis
gets disturbed two images - Diplopia
34. Clinical Manifestations
External Opthalmoplegia – Eyeball fails to move
Diplopia – Two images of one object
Internal Opthalmoplegia – Fixed Dilated pupils
(parasympathetic – III cranial nerve –
Occulomotor )
Ptosis of Upper Eyelid – upper eyelid drops
down like a curtain – parasympathetic supply.
Orbital Apex Syndrome – If Optic Nerve
Involvement is present.
35. BLOW IN FRACTURE
Fragmented bones of the orbital floor are
displaced into the orbit.
Proptosis – Exopthalmous
More commonly seen in fractures of – orbital roof
37. Forced Duction Test
Prior to the performance
of a forced duction test,
a cotton-tipped
applicator is soaked
with topical anesthetic
drops and held against
the limbus for a few
minutes.
Fine-toothed forceps
are then used to grasp
the conjunctiva and
Tenon’s capsule just
posterior to the limbus.
The patient is then
asked to look in the
direction of restriction of
movement of the eye .
40. IMAGING
CT Scan – Orbit
- To visualize the fractured segments
- CT Scan – also helps evaluate the Intraorbital
volume. By using a software to compare the
normal orbital volume to the affected
- MRI
43. In 1984 Smith and colleagues introduced the
concept that Volkmann’s contracture might occur as
a result of elevated intraorbital compartmental
pressure
Although this phenomenon was well known in
orthopedic literature , to occur within extremities, it
was unproven in orbit
Applying this concept to the orbit Smith and
colleagues recommended surgical intervention in
the elderly , in individuals who are hypotensive , and
for small or linear orbital floor fracture with
coexsisting diplopia.
44. Indications for surgical
managment
Unresolving soft tissue entrapment with disabling
diplopia
Enopthalmous greater than 2mm
CT scan evidence of a large fracture
SURGICAL MANAGEMENT :
1.CLOSED REDUCTION –
Transantrally.- Caldwell Luc Procedure
Trannasally – Through inferior turbinate – foley’s
catheter
46. SAGITAL SECTION THROUGH ORBIT &
GLOBE
C- Palpebral
Conjuntiva
IO- Inferior Oblique
muscle
IR- Inferior Rectus
Muscle
OO- Orbicularis Oculi
OS – Orbital Septum
P -
Periosteum/Periorbita
TP- Tarsal Plate.
47. Orbicularis Oris Muscle
Innervated by Cranial Nerve VII
Upper Eyelid – Levator
Palpebral Superioris – Cranial
Nerve III
Orbicularis Oculi -
Orbital and
Palpebral Portions
Palpebral Portion is divided into
fibers -
Pretarsal Portion - in front of
the tarsus.
Preseptal Portion - in front of
48. Subciliary Incision
The incision is approximately 2 mm below the eyelashes
and can be extended laterally as necessary (top dashed line). It is
made throug skin only.
49. Subcutaneous dissection of skin, leaving
pretarsal portion of orbicularis muscle
attached to tarsus. Dissection 4-6mm
inferiorly in this plane is adequate
Subcutaneous dissection through
the lid margin
50. Use of scissors to dissect through
orbicularis oculi muscle over lateral orbital
rim to identify
periosteum.
51. Incision through the bridge of orbicularis
oculi muscle.
Sagital plane through orbit showing
incision of the bridge of orbicularis oculi
muscle.
52. - Incision through periosteum along
anterior maxilla, 3 to 4 mm inferior to
infraorbital rim.
- Note the pretarsal muscle still
remaining on the inferior tarsus and
the orbital septum, which restricts the
orbital fat from entering the field.
- Subperiosteal dissection of anterior
maxilla and orbital floor. Note that the
periosteal elevator entering the orbit is
placed almost vertically as dissection
proceeds behind the rim.
-In the anterior region, the floor of the orbit
is at a lower level than the crest of the rim,
necessitating dissection inferiorly just
53. Sagital plane through orbit showing subperiosteal dissection of
the anterior maxilla and orbital floor.
54. TRANSCONJUCTIVAL
APPROACH
•Fig.1 - Incision of the conjuctiva below the tarsal plate
• Fig 2 - Incision through periosteum. To facilitate this maneuver, a traction
suture is placed through the cut end of the conjunctiva to retract the tissue and
maintain the position of the corneal shield.
•Small retractors are placed so that the lower lid is retracted to the level of the
anterior surface of the infraorbital rim.
•The intervening tissue along the infraorbital rim is the periosteum. The incision
is made through the periosteum just posterior to the infraorbital rim.
55. •Sagital plane through the orbit and globe demonstrating
level and plane of incision. The conjunctiva and lower lid
retractors are incised with scissors.
56. SUBPERIOSTEAL DISSECTION OF THE ORBITAL FLOOR.
Note the traction suture placed through the cut end of the
conjunctiva, which assists in retracting the conjunctiva and
maintains the corneal shield in place.
57. Orbital Floor Dissection
•Periorbital is elevated from the
underlying bone
•As dissection continues
posterolaterally, the inferior orbital
fissure are visualized
•The periorbital dissection along the
orbital floor proceeds posteriorly in a
twohanded technique using a
malleable ribbon retractor with a
wide rounded tip and a periosteal
elevator.
•In order to ensure a clean periosteal
dissection, the bony contours must
58. Surgical Exposure
After periorbital
dissection is
performed, adequate
exposure, (proper
retraction) and
illumination of the
fractured area is
imperative.
Malleable retractors,
spoons and special
orbital retractors
designed for the globe
59. •Transition between anterior mid
orbit , the orbital floor slopes
upwards giving rise to the –
posterior medial bulge & Slightly
convex bony platform
•Elevator passed transversely
along the inferior orbital fissure
•Infraorbital neurovascular bundle
can be visualized first shining
through the thin bony roof of its
canal
•Then it becomes directly visible in
the infraorbital groove
•Depending on the amount and
severity of comminution around
60. EXTENT OF DISSECTION
•Taking into account the extent of
fracture, the periorbital dissection
stops at the medial border of the
inferior orbital fissure leaving
the soft tissue invagination intact
•Laterally, the dissection is
continued to the posterior edge of
the floor to the orbital process of
the palatine bone. The suture
between the maxilla and the
palatine bone is indistinguishable
in the adult skull.
•Medially the periorbital
dissection (as shown in the
anatomic specimen) extends to
the zone over the internal orbital
buttress where the orbital floor
61. •In many cases a periorbital
dissection of the floor with a
tunnel medial to the
inferior orbital fissure will be
sufficient.
•For an EXTENDED ACCESS to
the posterior orbital floor, the
contents of the inferior orbital
fissure must be addressed and
transected to allow for this
additional access.
•The transsection is prepared with
a dissection along the inferior
portion of the lateral orbital wall in
order to create a second tunnel
62. •The intervening soft tissue
invagination is transected in a
stepwise fashion using
bipolar electrocautery and sharp
dissection across the fissure above
the level of
Müller’s vestigial muscle, stripping
the periorbita along the lateral
edge of the
inferior orbital fissure.
•This illustration demonstrates the
stripping of the periorbital layer
from the inferior lateral orbital wall
immediately adjacent to the inferior
orbital fissure with a sharp elevator
proceeding posteriorly.
63. Limit of Dissection
Inferiorly – Upto 28-30mm.
Laterally – Superior Orbital Fissure
Superiorly – Orbital roof dissection is stopped at
periorbital surrounding Recurrent Meningeal
Artery – passing through bony canal within the
Sphenofrontal suture line
Medially – Posterior extent – Posterior Ethmoidal
vessels , running in the Fronto-Ethmoidal Suture
line Anterior to Optic foramen.
64. •The subperiosteal dissection is
continued using a periosteal or
freer elevator in a
lateromedial direction and lifted up
and retracted by and by with the
ribbon
retractor until the entrance of the
apex is reached.
67. Bone Graft
Disadvantages :
•Additional Donor site needed
•Possible contour and dimensional changes due to
remodeling
•Difficult to shape according to patients anatomy
68. Porous Polyethylene Sheet
(PPE)
Disadvantages :
• Not Radiopaque (Not visble on Post Operative
Radiographs
•Lack of Rigidity when very thin wafer of PPE is used.
When a more thick rigid wafer is used there is a risk
of causing dystopia
69. COMPOSITE OF POROUS
POLYETHYLENE AND TITANIUM
MESH
By combining titanium mesh
with porous polyethylene –
Material becomes radioopaque
More rigid than porous PPE.
ADVANTAGE :
Stability
Contouring
Adequate in large three wall
fractures
Radiopacity
No Donor Site Needed
DISADVANTAGES : Less
Drainage from orbit than with
70. RESORBABLE MATERIALS
Thermoplastic and Non
Thermoplastic Materials
ADVANTAGES :
Availability Handling/
Contourability (only for
thermoplastics)
Smooth surface and smooth
edges
Disadvantages:
- No radiopacity
- Degradation of material with
possible contour loss Sterile
infection / inflammatory response
- Difficult to shape according to
patients anatomy (only for non-
thermoplastics)
71. COMPLICATIONS
EARLY COMPLICATIONS :
1. Hemorrhagic or orbital hematoma – treated by
-lateral cathotomy immediately, lateral canthal
Tendonlysis ,
Lateral canthotomy – indicated when –
- Decreased visual acuity
- Introcular pressure more than 40mmHg
- Proptosis
- Opthalmoplegia
72. Retrobulbar hemorrhage
- Rare, rapidly progressive
life threatening emergency
that results in accumulation
of blood in the retrobulbar
space
- Increased IOP
stretching of the optic
nerve & blockage of ocular
perfusion
- Proptosis , marked
subconjuctival ecchymosis
& edema ,
73. Symptoms seen are – pain , decreasing visual acuity,
diplopia
Treatment includes
iv mannitol – (used to treat raised intracranial
pressure)
Acteazolamide – carbonic anhydrase inhibitor ;
diuresis in PCT of kidney – excretion of NA, K, Cl –
lowering BP, IOP
Megadose Steroid Therapy – 100mg Dexa as an i.v.
bolus with 40mg 6 hourly in severe unresponsive
cases ( Anderson et al 1982)
3. Blindness
74. OCULOCARDIAC REFLEX/ TRIGEMINOCARDIAC/
TRIGEMINOVAGAL REFLEX –
- The oculocardiac reflex pathway begins with the
- afferent fibres of the long & short ciliary nerves that
travel with
- the opthalmic division of the trigeminal nerve to
- the gasserion ganglion via
- the sensory nucleus of the trigeminal nerve.
- In the floor of the 4th ventricle short internuncial
fibres in the reticular formation connect them with the
efferent pathway from the motor nucleus of the
vagus nerve to the depressor nerve ending in the
mucle tissue of the heart.
75. CLINICAL FEATURES –
- Bradycardia
- Faintness
- Further stimulation can lead to cardiac
dysrhythmias
- Atrioventricular blocks
- Asystole
- Bradycardia has been attributed to Trigeminal
derived vagal reflex
76. LATE COMPLICATIONS
Altered vision
Diplopia
Ectropion – lower eyelid turns outward
Epiphora – overflow of tears onto the face –
insufficient tear film drainage from eyed in that
tears will drain down the face rather than through
nasolacrimal system
Enopthalmous
79. Dissection between orbicularis oculi
muscle and orbital septum. The dissection
should
extend completely along the orbital rim and
superiorly to the level of subcutaneous
dissection.
Sagital plane through orbit showing level
and extent of dissection. Note the bridge of
orbicularis oculi muscle remaining between
the lid and skin/muscle flap.
Formaina – approx 2/3rd of the way up the medial orbital wall, within the frontoethmoidal suture line.
IMPORTANT SURGICAL LANDMARK to identify the cribriform plate
Orbital surgeons use these as landmarks for superior extent of orbital wall decompression
Pre-ganglionic parasympathetic fibres from – Edinger- Westphal nucleus in the mid brain , - relayed to --- ciliary ganglion – situated in lateral rectus muscle -----
Post ganglionic fibres – distributed paillary and ciliary muscles of the pupil through short ciliary nerve
UNEQUAL PUPILS – Anisocoria
Strabismus surgery - Loosens or tightens the eye muscle – which changes the alignmnet of eye related to each other .
SURGERY ON THE EXTRAOCULAR MUSCLE TO CORRECT THE MISALIGNMENT OF THE EYES
Abnormal position of eye - dystopia
Putterman’s – indications for surgical intervention
7 days of systemic corticosteroids – to speed the resolution of diplopia within the first 3 weeks
Persistent functional limitations – clear indication for surgery
Hertel Exopthalmometer – to measure enopthalmous
LAYERS OF EYELID - Skin; Subcutaneous areolar tissue; Striated muscle (orbicularis oculi)
Submuscular areolar tissue (contains main sensory nerves to lids)
Fibrous layer with tarsal plates; Nonstriated smooth muscle; Mucous membrane or conjunctiva