Primary Orbital Fracture Repair



Primary Orbital Fracture Repair




Atlas of the Oral and Maxillofacial Surgery Clinics of North America, 2021-03-01, Volume 29, Issue 1, Pages 51-77, Copyright © 2020



Key points

  • Predictable outcomes of complex orbital fracture patterns may be achieved by a structured and evidence-based approach.

  • Full anatomic and physiologic assessment of the fracture pattern using computed tomographic data and quantitative orthoptic analysis allows for precise planning of the surgical technique.

  • Preseptal transconjunctival access with transcaruncular extension and lateral swinging lid technique allows for ultimate exposure of the fracture complex.

  • Incarcerated orbital tissues must be identified and planned for released without surgical duress to the musculature.

  • Surgical momentum is progressing toward patient-specific implants for larger and more strategic fracture patterns. Medial and floor reconstruction to the apex can now be achieved.


Introduction


The nature of the problem

Fracture patterns of the anatomic orbit are common in contemporaneous oral and maxillofacial practice and exist in isolation or in concert with adjacent skeletal components. There is variance in complexity according to volume of energy transfer, and clinical heterogeneity in presentation because of soft tissue involvement, some of which may be vision threatening. Predicable outcomes therefore depend on prompt clinical diagnosis augmented by full anatomic description of the fracture configuration in conjunction with formal physiologic assessment. This full clinical data set then will inform prompt surgical management followed by evidence-based indications for surgery, approach, materials and methods used, together with prognostication to manage both surgeon and patient expectation.

Changes within the UK acute trust infrastructure have led to the adoption of major trauma centers, of which the Royal London Hospital was the prototype example, with 30 years of dedicated multidisciplinary trauma experience. This multidisciplinary trauma experience has led to proven increased survival rates in complex high-energy injury mechanisms, and greater survival rates resulting in higher numbers of complex facial injuries coming to surgery. The social demographic of East London, with a substantial history of criminal and even political violence, is well known. The UK Crime statistics indicate 30,000 violent crimes reported per year in East London, representing 19.5% of all crimes reported . The map of London in Fig. 1 demonstrates the significantly increased crime levels in the region.

Map of London demonstrating the significantly increased crime levels in the region. RLH, Royal London Hospital.
Fig. 1
Map of London demonstrating the significantly increased crime levels in the region. RLH, Royal London Hospital.


Surgical pathologic condition


Anatomic classification

Classically, orbital fracture patterns were described as either pure or impure. Impure fractures follow failure of the orbital rim, which can either be localized to the inferior orbital rim and associated with the orbital floor or propagate to the orbit from an adjacent facial bone fracture ( Table 1 ).

Table 1
Classification of orbital floor and wall fractures
Pure Impure Roof
Floor Segmental lower-orbital rim Isolated
Medial wall Nasomaxillary Craniofacial
Zygomatic
Maxillary
Nasoethmoid

The distinction of pure and impure of course has surgical significance but seems to be less important in the association with ocular damage, this born out clinically and by finite element analysis, which illustrates that the failure threshold for globe rupture is less than that of bone.

The surgical principle is to convert impure to pure orbital injuries and then treat the floor and medial walls accordingly. The size of the defect and position have both profound influence on surgical complexity and prognostic implications in terms of both aesthetics and function. Most surgeons will agree that fractures toward the posterior floor and upper medial third are more technically challenging and take longer to return to normal function postoperatively. Ahmad proposed a quantitative assessment of orbital fractures by splitting the floor and medial wall into separate thirds, as well as quantifying fracture severity in the rest of the facial skeleton, with recognition of the presence or absence of the posterior medial ledge. Jaquiery classified orbital fractures into 5 types according to surgical complexity, focusing on the size of defect and presence or absence of the posterior bone ledge medial to the infraorbital nerve, which facilitates anatomic dissection, and in addition, seating of the implant ( Table 2 ).

Table 2
Jaquiery classification
Stage Size of Defect (cm 2 ) Bone Ledge Medial To Orbital Fissure
I 1–2 Yes
II >2 Yes
III >2 No
IV Entire orbital floor/medial wall No
V Extension to roof No


Functional classification

Facilitation of binocular single vision requires the integration of a complex neuromuscular system involving 4 cranial nerves and 6 extraocular muscles working in a highly coordinated syncytium. The nuclei of the cranial nerves supplying these muscles are linked by the medial longitudinal fasciculus, which allows coordination with integration of the vestibular nerve. Disruption by intracranial damage can cause internuclear ophthalmoplegia. The muscles themselves are easily damaged or trapped in certain fracture patterns ( Table 3 ).

Table 3
Neurology of the orbit
Structure Function Pathologic Conditions
Oculomotor nerve
  • Motor to

    • Medial rectus

    • Inferior rectus

    • Superior rectus

    • Inferior oblique

  • Entrapment

  • Contusion

  • Snagging

  • Tearing

  • Neuromuscular

Trochlear nerve Motor to superior oblique
  • Contusion

  • Snagging

  • Tearing

  • Neuromuscular

Abducent nerve Motor to lateral rectus
  • Contusion

  • Snagging

  • Tearing

  • Neuromuscular

Medial longitudinal fasciculus Linking all intracranial nuclei
  • Head injury

  • Neurologic pathologic condition

Fracture progression is influenced by the mechanism and biomechanics of the orbit itself. In paediatric mechanisms, energy transfer commonly produces a linear fracture resulting herniation of the orbital contents with entrapment due to the elastic biomechanical nature of the orbital floor. Linear fracture pattern may occur with comparatively low-energy transfer and produce the so-called white-eye blowout fracture, which could be initially missed in accident and emergency departments. One of the symptoms is persistent postinjury nausea and vomiting, so a computed tomographic (CT) scan of the brain could incidentally expose the orbital fracture. Nevertheless, experience shows that CT scan is not always conclusive, and a trapdoor fracture could be missed easily.


Indications for surgery

The decision to operate follows comprehensive assessment of the fracture pattern in concert with the patient, in which clinical, medical, anatomic, and functional considerations are supported by objective evidence from detailed imaging and formal quantified orthoptic examination. With the exception of a vision-threatening condition that demands immediate surgical treatment, all indications are relative. Ultimately, it is a balanced decision between the surgeon and the patient according to individualization of the risk-benefit ratio.


Restoration of anatomy

The aesthetic form of the orbit involves harmony between the soft and hard tissues.

The orbital floor and medial wall have several key strategic landmarks, which maintain globe position. These landmarks have been described by Hammer with reference to the posterior medial bulge ( Fig. 2 ). Note the normal left side in this low orbital axial view (blue arrow) and the fractured right side (right arrow), and the sigmoid nature of the floor in sagittal view ( Fig. 3 ). In this view, the blue zone maintains the vertical height of the globe, and the sigmoid green zone maintains projection.

Axial CT scan at the level of the mid to lower orbit demonstrating Hammer’s key area ( blue arrow ). The fracture of the medial orbital wall compromises this ( red arrow ).
Fig. 2
Axial CT scan at the level of the mid to lower orbit demonstrating Hammer’s key area (
blue arrow ). The fracture of the medial orbital wall compromises this (
red arrow ).

Sagittal view of an intact orbit. Fractures involving the posterior and middle third of the orbital floor ( green line ) reduce globe projection; fractures of the anterior third ( blue line ) contribute to vertical discrepancy (hypoglobus).
Fig. 3
Sagittal view of an intact orbit. Fractures involving the posterior and middle third of the orbital floor (
green line ) reduce globe projection; fractures of the anterior third (
blue line ) contribute to vertical discrepancy (hypoglobus).

The concept of orbital volume remains but is, of course, related to the geometry of the bone orbit. It should also be appreciated that the volume comprises all the orbital adnexae, which includes fat and muscle, but in addition, the globe itself.


Restoration of function

In order to facilitate free movement of the globe, any trapped tissue within linear fractures, or physical limitation by sharp bone fragments, needs to be removed.


Primary orbital trauma decision making

Decision making for Orbital Reconstruction should follow a logical and stereotypical process which includes appraisal of physical findings, and assessment of hard and soft tissue subunits, with didactic surgical treatment planning ( Fig. 4 ).

Pathway and decision making in orbital trauma.
Fig. 4
Pathway and decision making in orbital trauma.


Emergency management

The orbit is described as a 4-walled pyramid contained by the orbital septum constrained by the lateral and medial canthal tendons, making the orbital contents vulnerable to compartment syndrome. Although an expanding retrobulbar hematoma is recognized, it must also be appreciated that intraorbital surgical emphysema, cerebrospinal fluid, and displaced bone fragments can be implicated.

Although medical management in the form of acetazolamide, mannitol, and hydrocortisone is described, lateral cantholysis in a timely manner is frequently vision saving.

Fig. 5 demonstrates an axial view of a medial wall fracture (red arrows) and a retrobulbar hematoma (blue arrows).

Axial view of a medial wall fracture ( red arrows ) and a retrobulbar hematoma ( blue arrows ).
Fig. 5
Axial view of a medial wall fracture (
red arrows ) and a retrobulbar hematoma (
blue arrows ).


Physical signs of ocular compartment syndrome

  • Ophthalmoplegia

  • Tense and proptosed globe

  • Loss of red vision

  • Loss of visual acuity

  • Escalating pain

The risk of ocular damage in facial injuries has been described many times, and the famous mnemonic device of BAD ACT has been constructed to raise awareness:

B: Blow out

A: Acquity

D: Diplopia

A: Amnesia

CT: Comminuted trauma

These injuries can frequently be difficult to assess because of acute periorbital swelling or may be masked by substance or alcohol abuse and a lowered level of consciousness. High-energy mechanism injured patients with multisystem injuries may mask orbital injuries that are not life threatening ( Box 1 ).

Box 1
Risk factors for ocular involvement

  • Significant volume of trauma

  • Orbital fracture: increased probability with increasing size

  • Multiple fractures: particularly involving orbital cancellous bone

  • Impaired consciousness: pain is less of a feature


Diagnosis, quantification, and prognostication of fracture pattern

CT scan analysis is central to diagnosis and planning treatment as well as to prognostication.

The sequential analysis of axial-coronal-sagittal formatted scans with measurement of bone loss and even angulation of fragments can be conducted near the patient with modern PACS systems.

Interpretation will influence the incision with the need for lateral and medial extensions to achieve predictable access, which materials to reconstruct, and risks to anatomic structures.

CT scans can also be interrogated to both diagnose and prognosticate functional deficits because of muscular involvement. The classic description of a trapdoor fracture typically seen in the pediatric or adolescent, otherwise known as the white-eye blowout fracture, is an example.

The CT scans visualized in coronal format demonstrate the region (blue square) of the fracture that is typically close to the infraorbital canal (green arrow) ( Fig. 6 ).

Coronal CT scan demonstrating region of an orbital floor fracture with herniation of contents ( blue zone ); the infraorbital canal is demonstrated by the green arrow.
Fig. 6
Coronal CT scan demonstrating region of an orbital floor fracture with herniation of contents (
blue zone ); the infraorbital canal is demonstrated by the green arrow.

The sagittal view illustrates the small size of the fracture (T), and soft tissue windows may distinguish between muscle and fat prolapse ( Fig. 7 ).

Sagittal fracture of the orbital floor trapdoor fracture T.
Fig. 7
Sagittal fracture of the orbital floor trapdoor fracture T.

This fracture pattern is not exclusively seen in young patients and is not always confined to the floor. The author has seen this pattern in older patients and affecting the medial wall involving medial rectus and superior oblique.

The scan, soft tissue windows, coronal format demonstrates the fracture (blue arrow) and the superior oblique (red arrows) ( Fig. 8 ).

Coronal CT scan. Soft tissue windows demonstrating a high medial wall fracture ( blue arrow ) with distortion and incarceration of superior oblique ( red arrows ).
Fig. 8
Coronal CT scan. Soft tissue windows demonstrating a high medial wall fracture (
blue arrow ) with distortion and incarceration of superior oblique (
red arrows ).

CT scans may also support orthoptic diagnosis and prognosticate on the possibility of postoperative functional defect. Orthoptic examination is mandatory for all clinical diagnoses of diplopia and will help prognosticate ( Table 4 ).

Table 4
Classification of diplopia
Binocular Diplopia Upgaze Downgaze Postoperative
I Yes No Possible, self-limiting
II No No Likely
III Yes Yes Very likely
Complex Yes Yes Extremely likely

Diplopia on downgaze is a predictor of the likelihood of postoperative diplopia, although it must be appreciated that the Hess chart only examines to 30° of elevation/depression, so type II and III may be more common than first appreciated.

Radiological predictors of postoperative diplopia included bone spurs in close proximity (blue arrow showing involvement with inferior rectus) ( Fig. 9 ).

Sagittal CT scan. Soft tissue windows demonstrating involvement of inferior rectus (IR) with the anterior fracture margin ( arrow ).
Fig. 9
Sagittal CT scan. Soft tissue windows demonstrating involvement of inferior rectus (IR) with the anterior fracture margin (
arrow ).

Another prognostic indicator is the change in shape of the muscle bellies, seen in coronal section.

This can be seen in both the medial rectus and, in this case, the inferior rectus. Note the ribbon shape of the normal side (blue arrow) compared with the rounder fractured side (red arrow) ( Fig. 10 ).

Coronal CT scan. Soft tissue window demonstrating the normal shape of inferior rectus ( blue arrow ) and the abnormal contour of inferior rectus caused by a floor fracture ( red arrow ).
Fig. 10
Coronal CT scan. Soft tissue window demonstrating the normal shape of inferior rectus (
blue arrow ) and the abnormal contour of inferior rectus caused by a floor fracture (
red arrow ).


Choice of material

The function of reconstruction material for primary repair has now become more objective. The choice of material depends on the anatomic and functional deficit ( Table 5 ).

Table 5
Justification of choice of orbital reconstruction material
Defect Defect Material Special consideration
Single wall Trapdoor Polydiaoxanone sulfate
Single wall, loss contour Anatomic loss Preshaped titanium
Floor, medial wall Anatomic loss Preshaped titanium
Approach, apex Anatomic loss Custom-made Navigation
Approach, skull base Anatomic loss Custom-made Navigation
Large combined defect Anatomic Loss 2-part custom-made Navigation

For simple defects, which in essence simply partition the orbit from adjacent anatomy, the polydiaoxanone sulfate (PDS) membrane is a very acceptable choice, easy to use, and well tolerated.

If the fracture size according to local anatomy and relationship to key structures is considered, then treatment planning becomes logical. In the schematic of the right orbit ( Fig. 11 ), floor (light blue defect) and medial wall (blue defect), which do not transgress the white line described by Jaquiery, are extremely predictable when reconstructed by preformed plates. The red areas of the apical third have close proximity to the optic nerve, and the high medial wall can be technically challenging to check plate positioning; for that reason, a custom plate with or without support by navigation is required.

Three-dimensional image of the right orbit. The anatomic structures with distances are illustrated, and the position of the fracture pattern within the orbit will dictate the strategic choice of material (see text). AE, anterior ethmoidal; ALC, anterior lacrimal crest; FZ frontozygomatic; ION Infraorbital nerve; ON, optic nerve; PE, posterior ethmoidal; SON; superior orbital nerve.
Fig. 11
Three-dimensional image of the right orbit. The anatomic structures with distances are illustrated, and the position of the fracture pattern within the orbit will dictate the strategic choice of material (see text). AE, anterior ethmoidal; ALC, anterior lacrimal crest; FZ frontozygomatic; ION Infraorbital nerve; ON, optic nerve; PE, posterior ethmoidal; SON; superior orbital nerve.

The prefabricated plates are deficient laterally (purple zone), and for that reason a second plate (PDS), or alternatively a custom plate, is required.

The anterior ethmoidal and posterior ethmoidal foramina are illustrated but are anatomically inconsistent, and vessels are invariably thrombosed in primary surgery.

The dimensions of a typical prefabricated plate are illustrated in Fig. 12 in millimeters. The plate may be divided according to reconstructive requirements. Moderate defects floor (green), junctional zone (red), and medial wall (yellow) can be reconstructed, but lateral defects (blue) need further support. The footplate needs to remain in only the largest defects and can often be removed, simplifying plate placement.

A typical preformed plate as favored by the author for moderate orbital floor defects with loss of 3D contour. The various regions of the plate are illustrated in color regions, and the dimensions of the components are in millimeters.
Fig. 12
A typical preformed plate as favored by the author for moderate orbital floor defects with loss of 3D contour. The various regions of the plate are illustrated in color regions, and the dimensions of the components are in millimeters.


Timing of surgery

There is anecdotal and published evidence to suggest that pediatric trapdoor defects are best operated on as soon as possible. Although this is the ideal, often presentation is delayed. The author has had good outcomes even in delayed cases. The surgical approach is easiest performed following resolution of chemises and lower-eyelid swelling, which occurs between 4 and 10 days after injury. The timeframe allows for treatment planning on a semielective pathway and also for fabrication of a custom plate if indicated. After 3 to 4 weeks, fibrous adhesions start to be noticeable, and by 6 weeks, the orbit begins to behave as a revision case.


Surgical approach

Historical access to the orbit has undergone a significant evolution to achieve adequate surgical access in a cosmetically privileged region. Modern reconstructive principles have driven the development of more cosmetic incisions around the orbit that deliver at least equivalent, but, in fact, better surgical access. The eyelid can be divided anatomically and philosophically into 2 distinct zones:

  • Anterior lamella, which consists of skin and orbicularis oculi

  • Posterior lamella, which consists of conjunctiva and tarsal plate

Approaches to the orbit can be described in terms of the position of the initial incision; both techniques separate the anterior and posterior lamellae along the plane of the middle lamella, scarring of which is implicated in both the pathologic condition and the secondary correction of ectropion and entropion. Further subclassification of the approaches is indicated in Table 6 .

Table 6
Classification of orbital approaches
Approach Lamellar
Infraorbital Anterior
Blepharoplasty Anterior
Lower lid Anterior
Transconjunctival: retroseptal Posterior
Transconjunctival: preseptal Posterior

Although it is accepted that good results can be achieved by all the orbital approaches, there is increasing evidence that the posterior lamellar approaches provide for excellent surgical access with superb aesthetic outcomes. In view of the fact that there is no disturbance of the orbicularis oculi muscle, the postoperative bruising and swelling are very much reduced, as is the time to resolution.

Improved lateral exposure with an anterior lamellar approach requires a cutaneous extension that can be very visible postoperatively, and even compromises lymphatic drainage if extensive. In the case of the posterior lamellar approach, the addition of a McCord swinging lid greatly increases the surgical access to the whole orbital floor and lateral wall. Medial exposure through an anterior approach is difficult and may require an additional incision Lynch incision, whereas, in the posterior approach, extension into the transcaruncular zone will achieve a predictable exposure to the whole medial wall.

The surgical exposure resulting from a lateral cantholysis with transcaruncular extension is very satisfactory and highly predictable, allowing access from above the frontozygomatic suture laterally to the skull base medially and well into the posterior third of the orbital floor.

There has been debate about the relative merits of surgical incision of the orbital septum. It must be appreciated that the septum may be violated in more significant orbital trauma, and in those cases, surgical exploration is more challenging, and postoperative results are less predictable. There is increasing understanding in the literature to support this, and the author has practiced the preseptal approach for 15 years with a low-complication and returned-to-theater rate, in a significant quantitative and qualitative trauma practice. It is for this reason that this approach is presented.


The technique

Initial assessment of the approach requires testing the integrity of the medial and lateral canthal tendons ( Fig. 13 ). The shape and integrity of the lateral canthus (blue arrow) are demonstrated here. At this time, the presence or absence of a “crow’s foot” can be determined to site the position of the lateral canthal release (red line). Note that the length of the incision is short, and simply enough to access the lateral tarsal plate.

Preoperative view of patient prepared for a transconjunctival incision with a McCord swinging lid ( red line ), at the lateral canthus ( blue arrow ).
Fig. 13
Preoperative view of patient prepared for a transconjunctival incision with a McCord swinging lid (
red line ), at the lateral canthus (
blue arrow ).

The cantholysis can be planned (blue arrow) ( Fig. 13 ) (red line) and made before the conjunctiva incision, or in a “cut as you go,” if during the subsequent dissection further access is required.

A 4/0 suture is placed through the midpoint of the lower eyelid ( Fig. 14 ), and evert the lid over a Desmarres retractor. This view demonstrates the tarsal plate (red arrows) nicely. Note that the tension within the eyelid causes an avascular zone; it is here that the incision is best sited (green arrows). The assistant applies gentle downward traction with both the Desmarres retractor and the suture.

The conjunctiva is everted over a Desmarres retractor, and the retractor is used to gently retract anteriorly ( blue arrows ). The tarsal plate is indicated by the red arrows. The incision line is sited where the conjunctival arcade blanches ( green arrows ). It is important to leave a cuff of conjunctiva below the tarsal plate.
Fig. 14
The conjunctiva is everted over a Desmarres retractor, and the retractor is used to gently retract anteriorly (
blue arrows ). The tarsal plate is indicated by the red arrows. The incision line is sited where the conjunctival arcade blanches (
green arrows ). It is important to leave a cuff of conjunctiva below the tarsal plate.

It is extremely important to ensure that there is a low-power setting of the diathermy. The settings required are “10to 10 blend and spray.”

The initial incisions are mapped out using a postage-stamp technique ( Fig. 15 ) using the cutting setting. It is important to have the lightest touch on the surgical instrument until just the conjunctiva is incised.

The conjunctival incision is marked using the cutting setting of the diathermy using a postage-stamp technique. The settings are 10 to 10 blend and spray.
Fig. 15
The conjunctival incision is marked using the cutting setting of the diathermy using a postage-stamp technique. The settings are 10 to 10 blend and spray.

This is then completed by joining each postage stamp, extending to the posterior aspect of the caruncle medially to the lateral canthus posteriorly.

The conjunctiva is then picked up with a small-toothed forceps, and tension is applied cranially (blue arrows) ( Fig. 16 ), leading to exposure of the middle lamella, which can be either incised with the diathermy or sharply cut with scissors.

The surgeon then retracts the free edge of the conjunctiva cranially ( blue arrows ). This demonstrated the middle lamella ( red arrows ). This plane is usually bloodless.
Fig. 16
The surgeon then retracts the free edge of the conjunctiva cranially (
blue arrows ). This demonstrated the middle lamella (
red arrows ). This plane is usually bloodless.

The free edge of the conjunctiva can then be advanced cranially, and this acts as an eye shield. Note the integrity of the orbital septum (blue arrows) ( Fig. 17 ).

The free edge of the conjunctiva is then used as a physiologic eye shield by gentle traction ( green arrows ). Note the intact orbital septum, which controls the orbital fat ( blue arrows ).
Fig. 17
The free edge of the conjunctiva is then used as a physiologic eye shield by gentle traction (
green arrows ). Note the intact orbital septum, which controls the orbital fat (
blue arrows ).

In this case, the skin incision is made with a number 15 scalpel ( Fig. 18 ).

In this case, the cantholysis is performed following the initial conjunctival incision, in a cut-as-you-go manner. The anterior tension of the eyelid is a key maneuver in facilitating this incision ( arrows ). The cantholysis can be performed before the conjunctival incision. This may be useful in revision cases.
Fig. 18
In this case, the cantholysis is performed following the initial conjunctival incision, in a cut-as-you-go manner. The anterior tension of the eyelid is a key maneuver in facilitating this incision (
arrows ). The cantholysis can be performed before the conjunctival incision. This may be useful in revision cases.

The incision is then clipped with a mosquito forceps for a period of not less than 25 seconds, with the curve extending cranially ( Fig. 19 ).

Following the skin incision, the canthal tendon is clipped with a hemostat for a minimum of 20 seconds.
Fig. 19
Following the skin incision, the canthal tendon is clipped with a hemostat for a minimum of 20 seconds.

The lateral tendon is then visualized, and this can be divided along the blue line ( Fig. 20 ). The downward traction (red arrows) allows the tendon to be tight, which greatly facilitates cutting the ligament with a pair of tenotomy scissors.

The canthal tendon is clearly demonstrated and can be cut with a pair of tenotomy scissors along the blue line. The incision is facilitated by the anterior traction ( arrows ).
Fig. 20
The canthal tendon is clearly demonstrated and can be cut with a pair of tenotomy scissors along the blue line. The incision is facilitated by the anterior traction (
arrows ).

Downward traction of the lower eyelid is crucial to facilitate separation of the tendon (blue arrows) ( Fig. 21 ).

The curve of the scissors is concave caudally. It is important to maintain traction on the lower eyelid in the direction go the blue arrows.
Fig. 21
The curve of the scissors is concave caudally. It is important to maintain traction on the lower eyelid in the direction go the blue arrows.

It is important to ensure that the tendon is freely mobile as demonstrated here ( Fig. 22 ).

The freedom of movement of the lateral canthus.
Fig. 22
The freedom of movement of the lateral canthus.

A Lacks tongue retractor is then placed on the orbital margin to control the septum. It is crucially important that Lacks retractor remains stable and static. The soft tissues can then be scooped forward using a Mitchell’s trimmer to mobilize the orbicularis forward ( Fig. 23 ).

Orbicularis oculi can now be swept forward off the periosteum. The tissue overlying the orbital rim is tented between the Lacks tongue retractor and the Desmarres.
Fig. 23
Orbicularis oculi can now be swept forward off the periosteum. The tissue overlying the orbital rim is tented between the Lacks tongue retractor and the Desmarres.

This allows full exposure of the orbital periosteum, which is sharply incised using diathermy ( Fig. 24 ).

The infraorbital bone is exposed using a cutting diathermy on coagulation setting.
Fig. 24
The infraorbital bone is exposed using a cutting diathermy on coagulation setting.

The orbit can then be entered laterally, and initial dissection continues along the subperiosteal pocket. The lateral wall is robust, and this is an easily developed plane, “the lateral wall is your friend” ( Fig. 25 ).

The approach to the subperiosteal plane is achieved by a lateral vector, “the lateral wall is your friend.”
Fig. 25
The approach to the subperiosteal plane is achieved by a lateral vector, “the lateral wall is your friend.”


Transcaruncular extension

One of the many advantages of the preseptal approach is that the surgical plane can readily be identified medially. The dissection is made easier by the use of multiple traction sutures (blue arrows). The mucosa can be cut with scissors along the green retrocaruncular line ( Fig. 26 ).

The preseptal dissection facilitates a straightforward exposure of the medial wall. Note the conjunctival traction sutures( blue arrows ), which facilitate the approach. The retrocaruncular mucosal incision can be made along the green line.
Fig. 26
The preseptal dissection facilitates a straightforward exposure of the medial wall. Note the conjunctival traction sutures(
blue arrows ), which facilitate the approach. The retrocaruncular mucosal incision can be made along the green line.

Subsequently, the orbital periosteum is incised along the rim and the soft tissue retracted along the green arrows and the medial orbit readily entered (blue arrow) ( Fig. 27 ).

Following incision to infraorbital periosteum, the plane of the subperiosteal approach to the medial wall is now straightforward ( blue arrow ). A quarter Langenbeck retractor along the free edge ( green arrows ) would greatly facilitate progress.
Fig. 27
Following incision to infraorbital periosteum, the plane of the subperiosteal approach to the medial wall is now straightforward (
blue arrow ). A quarter Langenbeck retractor along the free edge (
green arrows ) would greatly facilitate progress.


Dissection

The approach to the orbit follows a stereotypical route ( Fig. 28 ). Following subperiosteal access at the inferior orbital rim (1), the dissection proceeds laterally (2). The sphenozygomatic region allows a firm surface to develop the surgical plane. Following bipolar diathermy in the inferior orbital fissure (4), the posterior orbit is dissected to the palatine bone; this is the ledge that Jaquiery references.

The “zones of surgical bleeding.” The orange line indicates the stepwise progression in a strict numerical order (1-6). Each region must be fully dissected to facilitate onward progress. Laterally ( Blue zone ), the bone may be perforated by a branch of the maxillary artery; the yellow zone may contain branches of the infraorbital vessels, and the green and red zones may contain branches of the antral mucosae. The anterior and posterior ethmoidal vessels represent a theoretic risk.
Fig. 28
The “zones of surgical bleeding.” The orange line indicates the stepwise progression in a strict numerical order (1-6). Each region must be fully dissected to facilitate onward progress. Laterally (
Blue zone ), the bone may be perforated by a branch of the maxillary artery; the yellow zone may contain branches of the infraorbital vessels, and the green and red zones may contain branches of the antral mucosae. The anterior and posterior ethmoidal vessels represent a theoretic risk.

The medial dissection then proceeds (6). The medial tissue can usually be delivered by traction (indicated by the dotted lines).

The clinical view shows the fracture margins (blue arrows) ( Fig. 29 ) and the herniated contents. Should there be a sharp bone edge, then this is best removed with a “Mitchell’s trimmer” to enlarge the hole. The contents should be delivered very gently.

The margins of the fracture are identified ( arrows ), and the herniated contents (HC) are retrieved.
Fig. 29
The margins of the fracture are identified (
arrows ), and the herniated contents (HC) are retrieved.

The plate can then be gently insinuated between the bone and the soft tissues and fixed with screws.


Control of hemorrhage

Preseptal dissection is crucial to help avoid bleeding in a potentially closed space.

Operative bleeding can be managed according to the operating site ( Fig. 28 ).

  • 1.

    Lateral bleed (blue zone): This is usually from the zygomaticofacial vessel; the vessel can be diathermied, and the foramen can be packed with bone wax.

  • 2.

    Inferior orbital vessel tributary (yellow zone): This manifests as a small leak; the bleeding point can readily be identified, and bipolar cautery will normally arrest it.

  • 3.

    Maxillary floor (green zone): This manifests as a persistent and slow ooze. This is managed by use of a ribbon gauze soaked in 1:1000 adrenaline placed in the bleeding point for 2 minutes. This allows for slowing of the bleeding point for diathermy to be used. Occasionally the maxillary antrum itself will need packing, if necessary with removal of the orbital floor to facilitate access. The packing with a saline soaked swab maintained for 2 minutes is usually all that is required.

  • 4.

    Medial wall (red zone): This manifests as a persistent ooze that is complicated by reduced surgical vision due to the position. This is managed in a similar way to the maxillary sinus using an 1:1000 adrenaline soaked ribbon gauze. This area must be surgically dry to facilitate further surgery and patient safety.


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Primary Orbital Fracture Repair Simon Holmes FDS, RCS, FRCS Atlas of the Oral and Maxillofacial Surgery Clinics of North America, 2021-03-01, Volume 29, Issue 1, Pages 51-77, Copyright © 2020 Key points Predictable outcomes of complex orbital fracture patterns may be achieved by a structured and evidence-based approach. Full anatomic and physiologic assessment of the fracture pattern using computed tomographic data and quantitative orthoptic analysis allows for precise planning of the surgical technique. Preseptal transconjunctival access with transcaruncular extension and lateral swinging lid technique allows for ultimate exposure of the fracture complex. Incarcerated orbital tissues must be identified and planned for released without surgical duress to the musculature. Surgical momentum is progressing toward patient-specific implants for larger and more strategic fracture patterns. Medial and floor reconstruction to the apex can now be achieved. Introduction The nature of the problem Fracture patterns of the anatomic orbit are common in contemporaneous oral and maxillofacial practice and exist in isolation or in concert with adjacent skeletal components. There is variance in complexity according to volume of energy transfer, and clinical heterogeneity in presentation because of soft tissue involvement, some of which may be vision threatening. Predicable outcomes therefore depend on prompt clinical diagnosis augmented by full anatomic description of the fracture configuration in conjunction with formal physiologic assessment. This full clinical data set then will inform prompt surgical management followed by evidence-based indications for surgery, approach, materials and methods used, together with prognostication to manage both surgeon and patient expectation. Changes within the UK acute trust infrastructure have led to the adoption of major trauma centers, of which the Royal London Hospital was the prototype example, with 30 years of dedicated multidisciplinary trauma experience. This multidisciplinary trauma experience has led to proven increased survival rates in complex high-energy injury mechanisms, and greater survival rates resulting in higher numbers of complex facial injuries coming to surgery. The social demographic of East London, with a substantial history of criminal and even political violence, is well known. The UK Crime statistics indicate 30,000 violent crimes reported per year in East London, representing 19.5% of all crimes reported . The map of London in Fig. 1 demonstrates the significantly increased crime levels in the region. Fig. 1 Map of London demonstrating the significantly increased crime levels in the region. RLH, Royal London Hospital. Surgical pathologic condition Anatomic classification Classically, orbital fracture patterns were described as either pure or impure. Impure fractures follow failure of the orbital rim, which can either be localized to the inferior orbital rim and associated with the orbital floor or propagate to the orbit from an adjacent facial bone fracture ( Table 1 ). Table 1 Classification of orbital floor and wall fractures Pure Impure Roof Floor Segmental lower-orbital rim Isolated Medial wall Nasomaxillary Craniofacial Zygomatic Maxillary Nasoethmoid The distinction of pure and impure of course has surgical significance but seems to be less important in the association with ocular damage, this born out clinically and by finite element analysis, which illustrates that the failure threshold for globe rupture is less than that of bone. The surgical principle is to convert impure to pure orbital injuries and then treat the floor and medial walls accordingly. The size of the defect and position have both profound influence on surgical complexity and prognostic implications in terms of both aesthetics and function. Most surgeons will agree that fractures toward the posterior floor and upper medial third are more technically challenging and take longer to return to normal function postoperatively. Ahmad proposed a quantitative assessment of orbital fractures by splitting the floor and medial wall into separate thirds, as well as quantifying fracture severity in the rest of the facial skeleton, with recognition of the presence or absence of the posterior medial ledge. Jaquiery classified orbital fractures into 5 types according to surgical complexity, focusing on the size of defect and presence or absence of the posterior bone ledge medial to the infraorbital nerve, which facilitates anatomic dissection, and in addition, seating of the implant ( Table 2 ). Table 2 Jaquiery classification Stage Size of Defect (cm 2 ) Bone Ledge Medial To Orbital Fissure I 1–2 Yes II >2 Yes III >2 No IV Entire orbital floor/medial wall No V Extension to roof No Functional classification Facilitation of binocular single vision requires the integration of a complex neuromuscular system involving 4 cranial nerves and 6 extraocular muscles working in a highly coordinated syncytium. The nuclei of the cranial nerves supplying these muscles are linked by the medial longitudinal fasciculus, which allows coordination with integration of the vestibular nerve. Disruption by intracranial damage can cause internuclear ophthalmoplegia. The muscles themselves are easily damaged or trapped in certain fracture patterns ( Table 3 ). Table 3 Neurology of the orbit Structure Function Pathologic Conditions Oculomotor nerve Motor to Medial rectus Inferior rectus Superior rectus Inferior oblique Entrapment Contusion Snagging Tearing Neuromuscular Trochlear nerve Motor to superior oblique Contusion Snagging Tearing Neuromuscular Abducent nerve Motor to lateral rectus Contusion Snagging Tearing Neuromuscular Medial longitudinal fasciculus Linking all intracranial nuclei Head injury Neurologic pathologic condition Fracture progression is influenced by the mechanism and biomechanics of the orbit itself. In paediatric mechanisms, energy transfer commonly produces a linear fracture resulting herniation of the orbital contents with entrapment due to the elastic biomechanical nature of the orbital floor. Linear fracture pattern may occur with comparatively low-energy transfer and produce the so-called white-eye blowout fracture, which could be initially missed in accident and emergency departments. One of the symptoms is persistent postinjury nausea and vomiting, so a computed tomographic (CT) scan of the brain could incidentally expose the orbital fracture. Nevertheless, experience shows that CT scan is not always conclusive, and a trapdoor fracture could be missed easily. Indications for surgery The decision to operate follows comprehensive assessment of the fracture pattern in concert with the patient, in which clinical, medical, anatomic, and functional considerations are supported by objective evidence from detailed imaging and formal quantified orthoptic examination. With the exception of a vision-threatening condition that demands immediate surgical treatment, all indications are relative. Ultimately, it is a balanced decision between the surgeon and the patient according to individualization of the risk-benefit ratio. Restoration of anatomy The aesthetic form of the orbit involves harmony between the soft and hard tissues. The orbital floor and medial wall have several key strategic landmarks, which maintain globe position. These landmarks have been described by Hammer with reference to the posterior medial bulge ( Fig. 2 ). Note the normal left side in this low orbital axial view (blue arrow) and the fractured right side (right arrow), and the sigmoid nature of the floor in sagittal view ( Fig. 3 ). In this view, the blue zone maintains the vertical height of the globe, and the sigmoid green zone maintains projection. Fig. 2 Axial CT scan at the level of the mid to lower orbit demonstrating Hammer’s key area ( blue arrow ). The fracture of the medial orbital wall compromises this ( red arrow ). Fig. 3 Sagittal view of an intact orbit. Fractures involving the posterior and middle third of the orbital floor ( green line ) reduce globe projection; fractures of the anterior third ( blue line ) contribute to vertical discrepancy (hypoglobus). The concept of orbital volume remains but is, of course, related to the geometry of the bone orbit. It should also be appreciated that the volume comprises all the orbital adnexae, which includes fat and muscle, but in addition, the globe itself. Restoration of function In order to facilitate free movement of the globe, any trapped tissue within linear fractures, or physical limitation by sharp bone fragments, needs to be removed. Primary orbital trauma decision making Decision making for Orbital Reconstruction should follow a logical and stereotypical process which includes appraisal of physical findings, and assessment of hard and soft tissue subunits, with didactic surgical treatment planning ( Fig. 4 ). Fig. 4 Pathway and decision making in orbital trauma. Emergency management The orbit is described as a 4-walled pyramid contained by the orbital septum constrained by the lateral and medial canthal tendons, making the orbital contents vulnerable to compartment syndrome. Although an expanding retrobulbar hematoma is recognized, it must also be appreciated that intraorbital surgical emphysema, cerebrospinal fluid, and displaced bone fragments can be implicated. Although medical management in the form of acetazolamide, mannitol, and hydrocortisone is described, lateral cantholysis in a timely manner is frequently vision saving. Fig. 5 demonstrates an axial view of a medial wall fracture (red arrows) and a retrobulbar hematoma (blue arrows). Fig. 5 Axial view of a medial wall fracture ( red arrows ) and a retrobulbar hematoma ( blue arrows ). Physical signs of ocular compartment syndrome Ophthalmoplegia Tense and proptosed globe Loss of red vision Loss of visual acuity Escalating pain The risk of ocular damage in facial injuries has been described many times, and the famous mnemonic device of BAD ACT has been constructed to raise awareness: B: Blow out A: Acquity D: Diplopia A: Amnesia CT: Comminuted trauma These injuries can frequently be difficult to assess because of acute periorbital swelling or may be masked by substance or alcohol abuse and a lowered level of consciousness. High-energy mechanism injured patients with multisystem injuries may mask orbital injuries that are not life threatening ( Box 1 ). Box 1 Risk factors for ocular involvement Significant volume of trauma Orbital fracture: increased probability with increasing size Multiple fractures: particularly involving orbital cancellous bone Impaired consciousness: pain is less of a feature Diagnosis, quantification, and prognostication of fracture pattern CT scan analysis is central to diagnosis and planning treatment as well as to prognostication. The sequential analysis of axial-coronal-sagittal formatted scans with measurement of bone loss and even angulation of fragments can be conducted near the patient with modern PACS systems. Interpretation will influence the incision with the need for lateral and medial extensions to achieve predictable access, which materials to reconstruct, and risks to anatomic structures. CT scans can also be interrogated to both diagnose and prognosticate functional deficits because of muscular involvement. The classic description of a trapdoor fracture typically seen in the pediatric or adolescent, otherwise known as the white-eye blowout fracture, is an example. The CT scans visualized in coronal format demonstrate the region (blue square) of the fracture that is typically close to the infraorbital canal (green arrow) ( Fig. 6 ). Fig. 6 Coronal CT scan demonstrating region of an orbital floor fracture with herniation of contents ( blue zone ); the infraorbital canal is demonstrated by the green arrow. The sagittal view illustrates the small size of the fracture (T), and soft tissue windows may distinguish between muscle and fat prolapse ( Fig. 7 ). Fig. 7 Sagittal fracture of the orbital floor trapdoor fracture T. This fracture pattern is not exclusively seen in young patients and is not always confined to the floor. The author has seen this pattern in older patients and affecting the medial wall involving medial rectus and superior oblique. The scan, soft tissue windows, coronal format demonstrates the fracture (blue arrow) and the superior oblique (red arrows) ( Fig. 8 ). Fig. 8 Coronal CT scan. Soft tissue windows demonstrating a high medial wall fracture ( blue arrow ) with distortion and incarceration of superior oblique ( red arrows ). CT scans may also support orthoptic diagnosis and prognosticate on the possibility of postoperative functional defect. Orthoptic examination is mandatory for all clinical diagnoses of diplopia and will help prognosticate ( Table 4 ). Table 4 Classification of diplopia Binocular Diplopia Upgaze Downgaze Postoperative I Yes No Possible, self-limiting II No No Likely III Yes Yes Very likely Complex Yes Yes Extremely likely Diplopia on downgaze is a predictor of the likelihood of postoperative diplopia, although it must be appreciated that the Hess chart only examines to 30° of elevation/depression, so type II and III may be more common than first appreciated. Radiological predictors of postoperative diplopia included bone spurs in close proximity (blue arrow showing involvement with inferior rectus) ( Fig. 9 ). Fig. 9 Sagittal CT scan. Soft tissue windows demonstrating involvement of inferior rectus (IR) with the anterior fracture margin ( arrow ). Another prognostic indicator is the change in shape of the muscle bellies, seen in coronal section. This can be seen in both the medial rectus and, in this case, the inferior rectus. Note the ribbon shape of the normal side (blue arrow) compared with the rounder fractured side (red arrow) ( Fig. 10 ). Fig. 10 Coronal CT scan. Soft tissue window demonstrating the normal shape of inferior rectus ( blue arrow ) and the abnormal contour of inferior rectus caused by a floor fracture ( red arrow ). Choice of material The function of reconstruction material for primary repair has now become more objective. The choice of material depends on the anatomic and functional deficit ( Table 5 ). Table 5 Justification of choice of orbital reconstruction material Defect Defect Material Special consideration Single wall Trapdoor Polydiaoxanone sulfate Single wall, loss contour Anatomic loss Preshaped titanium Floor, medial wall Anatomic loss Preshaped titanium Approach, apex Anatomic loss Custom-made Navigation Approach, skull base Anatomic loss Custom-made Navigation Large combined defect Anatomic Loss 2-part custom-made Navigation For simple defects, which in essence simply partition the orbit from adjacent anatomy, the polydiaoxanone sulfate (PDS) membrane is a very acceptable choice, easy to use, and well tolerated. If the fracture size according to local anatomy and relationship to key structures is considered, then treatment planning becomes logical. In the schematic of the right orbit ( Fig. 11 ), floor (light blue defect) and medial wall (blue defect), which do not transgress the white line described by Jaquiery, are extremely predictable when reconstructed by preformed plates. The red areas of the apical third have close proximity to the optic nerve, and the high medial wall can be technically challenging to check plate positioning; for that reason, a custom plate with or without support by navigation is required. Fig. 11 Three-dimensional image of the right orbit. The anatomic structures with distances are illustrated, and the position of the fracture pattern within the orbit will dictate the strategic choice of material (see text). AE, anterior ethmoidal; ALC, anterior lacrimal crest; FZ frontozygomatic; ION Infraorbital nerve; ON, optic nerve; PE, posterior ethmoidal; SON; superior orbital nerve. The prefabricated plates are deficient laterally (purple zone), and for that reason a second plate (PDS), or alternatively a custom plate, is required. The anterior ethmoidal and posterior ethmoidal foramina are illustrated but are anatomically inconsistent, and vessels are invariably thrombosed in primary surgery. The dimensions of a typical prefabricated plate are illustrated in Fig. 12 in millimeters. The plate may be divided according to reconstructive requirements. Moderate defects floor (green), junctional zone (red), and medial wall (yellow) can be reconstructed, but lateral defects (blue) need further support. The footplate needs to remain in only the largest defects and can often be removed, simplifying plate placement. Fig. 12 A typical preformed plate as favored by the author for moderate orbital floor defects with loss of 3D contour. The various regions of the plate are illustrated in color regions, and the dimensions of the components are in millimeters. Timing of surgery There is anecdotal and published evidence to suggest that pediatric trapdoor defects are best operated on as soon as possible. Although this is the ideal, often presentation is delayed. The author has had good outcomes even in delayed cases. The surgical approach is easiest performed following resolution of chemises and lower-eyelid swelling, which occurs between 4 and 10 days after injury. The timeframe allows for treatment planning on a semielective pathway and also for fabrication of a custom plate if indicated. After 3 to 4 weeks, fibrous adhesions start to be noticeable, and by 6 weeks, the orbit begins to behave as a revision case. Surgical approach Historical access to the orbit has undergone a significant evolution to achieve adequate surgical access in a cosmetically privileged region. Modern reconstructive principles have driven the development of more cosmetic incisions around the orbit that deliver at least equivalent, but, in fact, better surgical access. The eyelid can be divided anatomically and philosophically into 2 distinct zones: Anterior lamella, which consists of skin and orbicularis oculi Posterior lamella, which consists of conjunctiva and tarsal plate Approaches to the orbit can be described in terms of the position of the initial incision; both techniques separate the anterior and posterior lamellae along the plane of the middle lamella, scarring of which is implicated in both the pathologic condition and the secondary correction of ectropion and entropion. Further subclassification of the approaches is indicated in Table 6 . Table 6 Classification of orbital approaches Approach Lamellar Infraorbital Anterior Blepharoplasty Anterior Lower lid Anterior Transconjunctival: retroseptal Posterior Transconjunctival: preseptal Posterior Although it is accepted that good results can be achieved by all the orbital approaches, there is increasing evidence that the posterior lamellar approaches provide for excellent surgical access with superb aesthetic outcomes. In view of the fact that there is no disturbance of the orbicularis oculi muscle, the postoperative bruising and swelling are very much reduced, as is the time to resolution. Improved lateral exposure with an anterior lamellar approach requires a cutaneous extension that can be very visible postoperatively, and even compromises lymphatic drainage if extensive. In the case of the posterior lamellar approach, the addition of a McCord swinging lid greatly increases the surgical access to the whole orbital floor and lateral wall. Medial exposure through an anterior approach is difficult and may require an additional incision Lynch incision, whereas, in the posterior approach, extension into the transcaruncular zone will achieve a predictable exposure to the whole medial wall. The surgical exposure resulting from a lateral cantholysis with transcaruncular extension is very satisfactory and highly predictable, allowing access from above the frontozygomatic suture laterally to the skull base medially and well into the posterior third of the orbital floor. There has been debate about the relative merits of surgical incision of the orbital septum. It must be appreciated that the septum may be violated in more significant orbital trauma, and in those cases, surgical exploration is more challenging, and postoperative results are less predictable. There is increasing understanding in the literature to support this, and the author has practiced the preseptal approach for 15 years with a low-complication and returned-to-theater rate, in a significant quantitative and qualitative trauma practice. It is for this reason that this approach is presented. The technique Initial assessment of the approach requires testing the integrity of the medial and lateral canthal tendons ( Fig. 13 ). The shape and integrity of the lateral canthus (blue arrow) are demonstrated here. At this time, the presence or absence of a “crow’s foot” can be determined to site the position of the lateral canthal release (red line). Note that the length of the incision is short, and simply enough to access the lateral tarsal plate. Fig. 13 Preoperative view of patient prepared for a transconjunctival incision with a McCord swinging lid ( red line ), at the lateral canthus ( blue arrow ). The cantholysis can be planned (blue arrow) ( Fig. 13 ) (red line) and made before the conjunctiva incision, or in a “cut as you go,” if during the subsequent dissection further access is required. A 4/0 suture is placed through the midpoint of the lower eyelid ( Fig. 14 ), and evert the lid over a Desmarres retractor. This view demonstrates the tarsal plate (red arrows) nicely. Note that the tension within the eyelid causes an avascular zone; it is here that the incision is best sited (green arrows). The assistant applies gentle downward traction with both the Desmarres retractor and the suture. Fig. 14 The conjunctiva is everted over a Desmarres retractor, and the retractor is used to gently retract anteriorly ( blue arrows ). The tarsal plate is indicated by the red arrows. The incision line is sited where the conjunctival arcade blanches ( green arrows ). It is important to leave a cuff of conjunctiva below the tarsal plate. It is extremely important to ensure that there is a low-power setting of the diathermy. The settings required are “10to 10 blend and spray.” The initial incisions are mapped out using a postage-stamp technique ( Fig. 15 ) using the cutting setting. It is important to have the lightest touch on the surgical instrument until just the conjunctiva is incised. Fig. 15 The conjunctival incision is marked using the cutting setting of the diathermy using a postage-stamp technique. The settings are 10 to 10 blend and spray. This is then completed by joining each postage stamp, extending to the posterior aspect of the caruncle medially to the lateral canthus posteriorly. The conjunctiva is then picked up with a small-toothed forceps, and tension is applied cranially (blue arrows) ( Fig. 16 ), leading to exposure of the middle lamella, which can be either incised with the diathermy or sharply cut with scissors. Fig. 16 The surgeon then retracts the free edge of the conjunctiva cranially ( blue arrows ). This demonstrated the middle lamella ( red arrows ). This plane is usually bloodless. The free edge of the conjunctiva can then be advanced cranially, and this acts as an eye shield. Note the integrity of the orbital septum (blue arrows) ( Fig. 17 ). Fig. 17 The free edge of the conjunctiva is then used as a physiologic eye shield by gentle traction ( green arrows ). Note the intact orbital septum, which controls the orbital fat ( blue arrows ). In this case, the skin incision is made with a number 15 scalpel ( Fig. 18 ). Fig. 18 In this case, the cantholysis is performed following the initial conjunctival incision, in a cut-as-you-go manner. The anterior tension of the eyelid is a key maneuver in facilitating this incision ( arrows ). The cantholysis can be performed before the conjunctival incision. This may be useful in revision cases. The incision is then clipped with a mosquito forceps for a period of not less than 25 seconds, with the curve extending cranially ( Fig. 19 ). Fig. 19 Following the skin incision, the canthal tendon is clipped with a hemostat for a minimum of 20 seconds. The lateral tendon is then visualized, and this can be divided along the blue line ( Fig. 20 ). The downward traction (red arrows) allows the tendon to be tight, which greatly facilitates cutting the ligament with a pair of tenotomy scissors. Fig. 20 The canthal tendon is clearly demonstrated and can be cut with a pair of tenotomy scissors along the blue line. The incision is facilitated by the anterior traction ( arrows ). Downward traction of the lower eyelid is crucial to facilitate separation of the tendon (blue arrows) ( Fig. 21 ). Fig. 21 The curve of the scissors is concave caudally. It is important to maintain traction on the lower eyelid in the direction go the blue arrows. It is important to ensure that the tendon is freely mobile as demonstrated here ( Fig. 22 ). Fig. 22 The freedom of movement of the lateral canthus. A Lacks tongue retractor is then placed on the orbital margin to control the septum. It is crucially important that Lacks retractor remains stable and static. The soft tissues can then be scooped forward using a Mitchell’s trimmer to mobilize the orbicularis forward ( Fig. 23 ). Fig. 23 Orbicularis oculi can now be swept forward off the periosteum. The tissue overlying the orbital rim is tented between the Lacks tongue retractor and the Desmarres. This allows full exposure of the orbital periosteum, which is sharply incised using diathermy ( Fig. 24 ). Fig. 24 The infraorbital bone is exposed using a cutting diathermy on coagulation setting. The orbit can then be entered laterally, and initial dissection continues along the subperiosteal pocket. The lateral wall is robust, and this is an easily developed plane, “the lateral wall is your friend” ( Fig. 25 ). Fig. 25 The approach to the subperiosteal plane is achieved by a lateral vector, “the lateral wall is your friend.” Transcaruncular extension One of the many advantages of the preseptal approach is that the surgical plane can readily be identified medially. The dissection is made easier by the use of multiple traction sutures (blue arrows). The mucosa can be cut with scissors along the green retrocaruncular line ( Fig. 26 ). Fig. 26 The preseptal dissection facilitates a straightforward exposure of the medial wall. Note the conjunctival traction sutures( blue arrows ), which facilitate the approach. The retrocaruncular mucosal incision can be made along the green line. Subsequently, the orbital periosteum is incised along the rim and the soft tissue retracted along the green arrows and the medial orbit readily entered (blue arrow) ( Fig. 27 ). Fig. 27 Following incision to infraorbital periosteum, the plane of the subperiosteal approach to the medial wall is now straightforward ( blue arrow ). A quarter Langenbeck retractor along the free edge ( green arrows ) would greatly facilitate progress. Dissection The approach to the orbit follows a stereotypical route ( Fig. 28 ). Following subperiosteal access at the inferior orbital rim (1), the dissection proceeds laterally (2). The sphenozygomatic region allows a firm surface to develop the surgical plane. Following bipolar diathermy in the inferior orbital fissure (4), the posterior orbit is dissected to the palatine bone; this is the ledge that Jaquiery references. Fig. 28 The “zones of surgical bleeding.” The orange line indicates the stepwise progression in a strict numerical order (1-6). Each region must be fully dissected to facilitate onward progress. Laterally ( Blue zone ), the bone may be perforated by a branch of the maxillary artery; the yellow zone may contain branches of the infraorbital vessels, and the green and red zones may contain branches of the antral mucosae. The anterior and posterior ethmoidal vessels represent a theoretic risk. The medial dissection then proceeds (6). The medial tissue can usually be delivered by traction (indicated by the dotted lines). The clinical view shows the fracture margins (blue arrows) ( Fig. 29 ) and the herniated contents. Should there be a sharp bone edge, then this is best removed with a “Mitchell’s trimmer” to enlarge the hole. The contents should be delivered very gently. Fig. 29 The margins of the fracture are identified ( arrows ), and the herniated contents (HC) are retrieved. The plate can then be gently insinuated between the bone and the soft tissues and fixed with screws. Control of hemorrhage Preseptal dissection is crucial to help avoid bleeding in a potentially closed space. Operative bleeding can be managed according to the operating site ( Fig. 28 ). 1. Lateral bleed (blue zone): This is usually from the zygomaticofacial vessel; the vessel can be diathermied, and the foramen can be packed with bone wax. 2. Inferior orbital vessel tributary (yellow zone): This manifests as a small leak; the bleeding point can readily be identified, and bipolar cautery will normally arrest it. 3. Maxillary floor (green zone): This manifests as a persistent and slow ooze. This is managed by use of a ribbon gauze soaked in 1:1000 adrenaline placed in the bleeding point for 2 minutes. This allows for slowing of the bleeding point for diathermy to be used. Occasionally the maxillary antrum itself will need packing, if necessary with removal of the orbital floor to facilitate access. The packing with a saline soaked swab maintained for 2 minutes is usually all that is required. 4. Medial wall (red zone): This manifests as a persistent ooze that is complicated by reduced surgical vision due to the position. This is managed in a similar way to the maxillary sinus using an 1:1000 adrenaline soaked ribbon gauze. This area must be surgically dry to facilitate further surgery and patient safety. Case example 1: pure fracture The axial CT scan demonstrates the fracture (blue arrows) ( Fig. 30 ) and the region of the optic canal (yellow area). Note the extensive surgical emphysema. Fig. 30 Axial CT scan demonstrating a fracture in the right posteromedial third of the orbit ( arrows ). Note the extensive surgical emphysema and proximity to the optic nerve ( yellow area ). The coronal view ( Fig. 31 ) and sagittal view ( Fig. 32 ) again demonstrate the defect. Fig. 31 The coronal CT scan demonstrates the extent of the fracture ( arrows ). Fig. 32 The sagittal CT view again shows the posterior extent of the fracture ( arrows ). The large defect with proximity to the optic canal and medial extension to the orbital roof could only be managed predictably by a custom-made orbital plate. The postoperative views indicate a satisfactory position; the margins are indicated by blue arrows ( Figs. 33–35 ). Fig. 33 The axial CT scan shows a good medial wall reconstruction with good fracture margins ( arrows ). Fig. 34 The coronal CT scan demonstrating accurate reconstruction ( arrows ). Fig. 35 The sagittal CT scan shows adequate reconstruction of the posterior third ( arrow ) in addition the restoration of the S-shaped contour. Case 2: impure orbital fracture The coronal CT scan demonstrates a fracture extending from the medial wall (blue line) ( Fig. 36 ) through the junctional zone (red line), with the orbital plate cantilevered inferiorly (yellow arrows). The extra bone in the sinus (red arrows) is also noted. The lateral margin of the fracture extends on the body of the zygoma (green line). Fig. 36 In this coronal CT scan of an impure blowout fracture, the orbital floor and walls are demonstrated: floor in green, medial wall in blue, and the junctional zone in red. The cantilevered floor is denoted with yellow arrows and the anterior maxillary wall fractures are denoted with red arrows. The sagittal view shows no credible bone ledge posteriorly, and no anterior orbital margin (blue zone) ( Fig. 37 ). Fig. 37 The sagittal CT scan demonstrates a complete absence of the anterior orbital margin ( blue zone ) but an intact posterior ledge ( arrows ). This ledge is key to the reconstruction. The 3-dimensional (3D) reconstruction shows the displaced piriform aperture (blue arrows) and the orbital margin (red arrows) ( Fig. 38 ). Fig. 38 The nasomaxillary component with the piriform rim ( blue arrows ) and the rim ( red arrows ). The lateral extension precluded a standard plate, and a custom orbital plate was required. At surgery, the precise lateral margin articulation and the landing on the medial wall allowed localization of the orbital margin, and the fragments were fixed to the plate following reconstruction of the piriform aperture. The postoperative views show accurate placement of the prosthesis (blue arrows) ( Fig. 39 ), with good reconstruction of the intermediate zone (yellow zone) and the lateral extension (red zone and arrows) ( Fig. 40 ). Fig. 39 The axial CT scan shows a strong reconstruction ( arrow ). Fig. 40 The postoperative coronal CT scan illustrating key reconstructed zones, for which a custom plate is more predictable. The lateral extent of the fracture ( red zone and arrows ) is often deficient in off-the-shelf plates. The medial articulation is accurate ( blue arrows ), and the curve on the plate around the junctional zone ( yellow zone ) is restored perfectly. The sigmoid-shaped blue zone is also reproduced ( Fig. 41 ). Fig. 41 The sagittal CT scan shows the replication of the S-shaped curvature ( blue zone ) and the posterior margin ( arrow ). The 3D view in Fig. 42 shows faithful reconstruction of the orbital margin . Fig. 42 The 3D reconstruction with accurate piriform aperture and infraorbital reconstruction. Soft tissue closure Closure of the lateral canthus is normally problem free provided that some simple rules are observed. The lower eyelid is sutured with a 5/0 suture capturing the lateral aspect and is then sutured to the lateral canthus on the medial free edge (blue arrows) ( Fig. 43 ), allowing for approximation of the lid to the globe when tightened. Fig. 43 The canthal tendon should be considered as a tube and a 5/0 Vicryl suture on the outer quadrant of the lid, to the inner quadrant of the lateral canthus ( blue arrows ). The gray lines of the eyelids are then approximated using a 6/0 suture, which is tied first. The tension suture is then tied, and any skin incision is closed with the 6/0 suture ( Fig. 44 ). Fig. 44 It is important to approximate the lash line/gray lines well. This is with 6/0 Vicryl. Fig. 45 provides a postoperative view following lateral canthal repair. Fig. 45 The finished closure. The long suture Occasionally, particularly in extended dissections, the surgeon may have concerns about postoperative bleeding. There is an option to not tie the suture of the canthus until the following day ( Fig. 46 ). Fig. 46 On occasion in the vulnerable orbit, either technically demanding, difficult to hemostase, or if the patient has a coagulopathy, the suture can be left long and tied on the ward the next day. Postoperative recovery The patient is nursed head up and given icepacks in the recovery ward to self-apply. The patient is forbidden to blow their nose for 3 weeks. Eye observations, including Pain score Visual acuity Pupil size and reactivity Are performed every 15 minutes for 2 hours and thereafter every 30 minutes for 2 hours. Postoperative imaging Although it is appreciated that there is a movement to reduce the exposure to radiation, when large titanium orbital plates are placed, then postoperative imaging is essential. The postoperative view of a secondary referral clearly demonstrates poor positioning; the referring surgeon did not take a postoperative view as “the plate seated well”( Fig. 47 ). Fig. 47 This coronal CT scan demonstrates the need for adequate postoperative imaging. The referring surgeon radiographed the patient because of postoperative pain and was quite sure that the plate was in the correct place postoperatively. Results The author’s operative clinical practice is presented in Fig. 48 over a 5-year period. Fig. 48 The author’s operative clinical practice is presented here over a 5-year period. OMFS, oral and maxillofacial surgery. Although orbital access is required for maxillary and cranioorbital surgery, for the purposes of this article, these were excluded. The breakdown into pure and impure fractures is detailed in Fig. 49 . Fig. 49 The numbers of operated pure and impure blowout fractures. Most impure fractures included zygomatic patterns, nasomaxillary, or those complicated by segmentation of the orbital margin ( Fig. 50 ). Fig. 50 Classification of impure blowout fractures. Outcomes Using the methodology described in the text in the 5 years, there were a total of 329 pure orbital fractures and 289 impure orbits operated on. Complication rates were low; with no loss of sight, 13 cases returned to theater for plate repositioning, and 3 patients requiring lateral canthal revision. The author examined a consecutive series of prefabricated plate reconstructions (in preparation) and found that, out of a case series of 79 patients, with 45% involving the medial wall and a mean Jaquiery score of 3.2, with satisfactory plate position in 86%, only 3 cases returned to theater, all of these because the preformed plate was not large enough. No patients required secondary strabismus surgery. This study has led to the modification of the protocol to lower the threshold for custom plate, leading to greatly increased surgical accuracy approaching 95% in the next 25 cases despite higher Jaquiery scores (in press). Summary Orbital surgery can be performed in a predictable manner provided that an ordered diagnostic and surgical protocol can be followed. A posterior lamellar approach in a preseptal plane with a logical selection of reconstructive material is recommended. The use of a custom-made prosthesis greatly improves surgical accuracy and facilitates reconstruction in high-medial-wall and apical third fracture patterns without the absolute need for surgical navigation. Disclosure The author has nothing to disclose.

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