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Orbit flip book /live ppt
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 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.

 They felt these pateints were at higher risk of

Blow Out Fracture

 Term coined by – Smith and Regan – 1 957
 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

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

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Topics for Discussion

• Orbital anatomy
• Types of fractures
• Signs and symptoms
• Management

Orbital Anatomy

• The bony orbit refers to the shell of bone
which surrounds and protects the eye.

• The bony orbit is a pyramidal cavity with an
elliptical base presenting anteriorly and the
apex posteriorly

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Bony Orbit

• Seven bones form the bony orbit

– Maxilla
– Zygoma
– Lacrimal
– Ethmoid
– Palantine
– Sphenoid
– Frontal

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Superior Orbital Wall

• Formed by:

– Frontal bone
– Lesser wing of sphenoid

• Functions as:

– Floor anterior fossa

• Important structures:

– Supraorbital notch which transmits the
supraorbital nerve

Medial Orbital Wall

• Formed by (from anterior to posterior):

– Maxilla
– Lacrimal bone
– Ethmoid
– Sphenoid

• Important structures:

– Lamina papyracea

Lamina Papyracea

• Thin segment of the medial orbital wall
• Separates the orbit from the ethmoid air cells

Lateral Orbital Wall • 11

• Formed by:

– Zygomatic bone
– Greater wing of sphenoid

Orbital Floor

• Formed by:

– Maxilla
– Palatine

• Important structures:

– Infraorbital groove

• Transverses floor from lateral to medial
• Location of infraorbital nerve which supplies sensation

to check and ipsilateral upper alveolus and teeth

Inferior orbital Fissure

• Connects to pterygopalantine fossa
• Located between floor and lateral wall
• Transmits:

– Infra orbital Artery
– Maxillary division Trigeminal nerve
– Zygomatic Nerve
– Sphenopalatine Ganglion Branches
– Ophthalmic Vein Branches

Orbital Floor

• Forms roof of maxillary sinus
• Location of more blow out fractures due to

inherent weakness of bone overlying maxillary
sinus

Optic Canal

• Contains:

– Optic nerve
– Ophthalmic artery

• In Lesser wing of sphenoid

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Superior Orbital Fissure

• Separates lateral wall from roof
• Transmits the following structures:

– Oculomotor nerve (CN III)
– Trochlear nerve (CN IV)
– Abducens nerve (CN VI)
– Ophthalmic division of trigeminal

nerve

• Lacrimal, frontal and nasociliary Branches

– Ophthalmic vein
– Sympathetics from cavernous sinus

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Clinical Correlation

• Superior orbital fissure syndrome

– Ptosis
– External Ophthalmoplegia ( III, IV &VI )
– Anaesthesia of cornea (Nasociliary)
– Ipsilateral Numbness forehead, lateral orbital skin

• Orbital Apex Syndrome

– All of the above
– Visual Loss

Tonometer

Snellen chart

Subciliary Incision

The incision is approximately 2 mm below the eyelashes
and can be extended laterally as necessary (top dashed line). It is
made through skin only.

Subcutaneous dissection through
the lid margin

Subcutaneous dissection of skin, leaving
pretarsal portion of orbicularis muscle
attached to tarsus. Dissection 4-6mm
inferiorly in this plane is adequate

Use of scissors to dissect through orbicularis oculi muscle over
lateral orbital rim to identify periosteum.

Incision through the bridge of orbicularis

oculi muscle. Sagital plane through orbit showing incision

of the bridge of orbicularis oculi muscle.

- Incision through periosteum along - Subperiosteal dissection of anterior
anterior maxilla, 3 to 4 mm inferior to maxilla and orbital floor. Note that the
infraorbital rim. periosteal elevator entering the orbit is
- Note the pretarsal muscle still placed almost vertically as dissection
remaining on the inferior tarsus and proceeds behind the rim.
the orbital septum, which restricts -In the anterior region, the floor of the orbit
the orbital fat from entering the field. is at a lower level than the crest of the
rim, necessitating dissection inferiorly just

Sagital plane through orbit showing subperiosteal dissection of
the anterior maxilla and orbital floor.

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.

•Sagital plane through the orbit and globe demonstrating
level and plane of incision. The conjunctiva and lower lid
retractors are incised with scissors.

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.

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
two handed 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

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

•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 the
course of the

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

•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 alongside the vertical
softtissue

•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.

•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.

 OCULOCARDIAC REFLEX/ TRIGEMINO
CARDIAC/ TRIGEMINO VAGAL 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.

3D Printed Grafts – A great variety of printing materials allows for mechanical properties,
cheaper, easily accessible, less time-consuming and appearance accustomed to specific
applications.

More importantly, accessibility of robust 3D modelling software and powerful computer
processors, enables 3D models to be created at ease with typical desktop workstations.

a) Digital-3d Design- skull model - A 3D skull model was created in standard triangle
language (STL) format and refined with 3D modelling software

b) Area Specific Mesh Optimization -The relevant area including the orbital floor
defect and the contralateral intact orbital floor was cropped from the skull.

Afterwards, mesh reduction (decimation), smoothing and defect filling techniques
were applied to the 3D models to reduce its triangular complexity.

These mesh optimization steps were aimed at reducing the computational burden and
time required for printing

.

c) 3D Print Models- are produced with medically designated Acrylonitrile Butadiene
Styrene using an Industrial Grade fused deposition modelling (FDM) printer.

The model are created at a layer thickness of 0.178mm and sterilized by low temperature
hydrogen peroxide gas plasma following published recommendations before operation

d) Actual Custom Implant- A porous polyethylene sheet (0.85mm thick) is trimmed
and moulded to fit the size of defect according to the sterilized 3D printed model and
inserted to reconstitute the orbital floor

The time required to prepare the digital 3D models at the computer workstation will be
< 1 hour and the 3DP turnover time will be three working days.

Logistically, this enables 3DP models to be used for semi-elective situations where surgery
may be performed in 1–2 weeks.



Complications of Surgery

• Ectropion
• Lid retraction
• Persistent diplopia
• Malposition of eye
• Hypoaesthesia of V2
• Extrusion of orbital floor implant
• BLINDNESS

4. Complications
1. Acute surgical complications include loss of vision due to retrobulbar hematoma
or impingement of the orbital apex.

2. Delayed surgical complications depend on the surgical procedure used and
include entropion, ectropion, diplopia, infraorbital paresthesia, enophthalmos,
and blindness.
Surgical complications may include loss of vision, traumatic optic neuropathy, diplopia,
overcorrection or under correction of enophthalmos, lower eyelid retraction, bleeding,
infection, extrusion of the implant, infraorbital nerve damage with resultant
hypoesthesia, orbital congestion, and epiphora.

Most complications are the result of either malpositioning the implant or using the
wrong size implant.
Occasionally, trauma to the inferior rectus occurs during the attempt to release it from
the fracture site. Palsy may result. This usually resolves spontaneously but may take as
many as 3 months to resolve.

Factors to consider for surgery

• Site
• Location
• Severity
• What needs to be corrected



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.