Ординатура / Офтальмология / Английские материалы / Surgical Atlas of Orbital Diseases_Mallajosyula_2009

reconstructing the orbital bony support, and restoring normal orbital volume and structure.

FLOORFRACTURES

Orbital floor fractures are common, and result from blunt orbital trauma in which force is delivered to the thin bones of the orbital floor, typically along the infraorbital canal. Often, an orbital floor fracture will not involve the orbital rim, which is much thicker and stronger. In such an instance, the term "blowout fracture" is often applied. The term was first used by Smith and Regan in 1956 to describe orbital fractures caused by striking the orbital rim with a hurling ball.74-76

The orbital floor is the shortest of the walls. It consists of the roof of the maxillary sinus with a small contribution posteriorly from the palatine bone, and contains the infraorbital groove and canal. The edge of the canal forms a weak spot in the floor structure. Hence, most floor fractures extend up to the canal, but the canal is often left mostly intact.

Concomitant displaced zygomatic fractures should be repaired first, since reduction and fixation of the ZMC fracture will often reduce the floor fracture as well.65 Floor fractures are often associated with medial wall fractures. When making the decision to proceed with or forgo surgery, the total wall area involved by the fracture, including the floor and medial wall, must be taken into account and addressed.

The evaluation of a suspected floor fracture often requires CT scanning with coronal sections, which facilitates the assessment of bone displacement and extraocular muscle findings. It must be emphasized again that muscle entrapment is a clinical diagnosis, which should be supported by the radiologic evidence but need not be.

Extraocular muscle entrapment in the context of orbital floor fractures is not uncommon.(Figure 17.4) However, the finding of muscle entrapment can be subtle, and a high level of suspicion must be maintained (Figure 17.3). Tissue herniation is very common in the context of orbital floor blow-out fractures. All orbital tissues must be retrieved and repositioned into the orbit at the time of repair; otherwise, tissue incarceration can lead to necrosis and permanent muscle dysfunction.

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Our favored approach to the inferior orbit is through a transconjunctival approach.77-80 We usually avoid the lateral canthotomy and inferior cantholysis, but at times, when better exposure is required for a larger fracture, a tighter orbit, or more extensive herniation, the canthotomy and cantholysis can greatly aid in obtaining adequate exposure. Care must be taken to perform the exposure correctly to avoid postoperative complications.81 The inferior fornix and lateral canthus are infiltrated with 2-3 ml of local anesthetic containing 1% Lidocaine, 0.25% Bupivicaine, and 1:100,000 dilution of epinephrine. The patient's face and any wounds are carefully prepped with 5% Betadine solution, and sterile drapes are placed. We routinely place a lubricated plastic corneal protective shield on the globe.

First, forced ductions are performed to assess for muscle entrapment (Figure 17.7). Next, the assistant retracts the lower eyelid down with a Desmarres retractor. The surgeon uses a malleable retractor to sweep the orbital fat posteriorly and drape the conjunctiva and lower lid retractors over the inferior orbital rim (Figure 17.15A). The surgeon then uses a monopolar electrocautery device with a microdissection needle (such as the Colorado needle, Colorado biomedical, Evergreen, CO, USA) to cut through conjunctiva, lid retractors and orbital rim periosteum to reveal the bony rim. The incision is made inferiorly in the fornix (at least half way between the inferior edge of the tarsus and the deepest part of the fornix) to help minimize cicatricial changes (retraction or entropion) of the eyelid margin (Figure 17.15B). We then use a Freer elevator to lift the periorbita off of the orbital floor. Our dissection is guided by the CT findings: the initial sub-periosteal dissection is performed away from the fracture and then brought to the fracture site. The fracture edges are carefully defined and visualized. A malleable retractor is used to gently retract the globe superiorly while the herniated orbital contents are lifted back into the orbit using a Freer elevator. Often, the herniated tissues need to be bluntly separated from any early scars that form at the edge of the fracture and in the maxillary sinus; this must be done slowly and carefully, taking care to avoid injury to the infraorbital neurovascular bundle and the perforating artery. The maxillary sinus is typically well visualized through the fracture (Figure 17.15C).

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When the sinus is full of blood, we typically evacuate the blood using suction, which also improves visibility.

Once the herniated tissue is released, a Teflon sizer (DuPont, Wilmington, DE, USA) is used to assess the size of the needed implant (Figures 17.15D and E). In the absence of a sizer, aluminum foil from a suture packing, sterilized X-ray film, or any other similar strong and sterile material can be used. Adequate overlap with the fracture edges must be confirmed. Particular attention must be given to avoidance of orbital tissue incarceration between the implant and the fracture's bony ledges.

The implant is soaked in an antibiotic solution (e.g. bacitracin solution), and cut to size with the

appropriate scissors (Figure 17.15F). It is then molded into the proper curvature. It is slipped carefully into the orbit to cover the fracture (Figures 17.15G to I). If a porous polyethylene implant with high density "barrier" surface is used, the barrier side is oriented toward the orbital soft tissue and the porous surface turned toward the maxillary sinus. Care must be taken to avoid an implant that is too long which might cause damage to the orbital apex. The support of the implant by the bony ledges is confirmed, and any tissue incarceration is reduced. The end point should be a stable implant that can slide 1 mm with gentle force but is otherwise immobile. When implant stability is in question, the implant should be rigidly fixated to the bony rim with a titanium microscrew.

Figure 17.15A: The lower lid is retracted and the rim palpated. A malleable retractor is used to protect the globe, expose the rim, and keep the fat pads pushed posteriorly

Figure 17.15B: The monopolar unit with a micro-dissection needle is used to incise conjunctiva, eyelid retractors and orbital rim periosteum deep in the inferior fornix

Figure 17.15C: After elevation of the periorbita with a freer elevator, the orbital floor fracture is exposed. A combination of the freer elevator and thin retractors is used to retrieve any prolapsing orbital contents from the maxillary sinus

Figure 17.15D: The position, dimensions and posterior-most aspect of the floor fracture are measured with the help of a probe

236 Surgical Atlas of Orbital Diseases

Figure 17.15J: Once the implant is stable, the eyelid retractors are reapproximated using buried interrupted sutures

A screw can be placed right through the Medpor Barrier implant or through the TITAN MTB implant. Some surgeons favor surgical glue for fixating the implant temporarily. The Desmarres retractor is then removed, and the eyelid retractors sutured with buried, interrupted 7-0 polyglactin (Vicryl) suture using 3-point fixation (Figure 17.15H). The conjunctiva is left unsutured.

When no bony ledge is present to support the fracture, cantilevering of the TITAN implant or a Medpor Channel plate over the rim can provide rigid fixation. Some surgeons favor titanium mesh in this situation.

Other methods of fixation include the use of fibrin sealant (such as Tisseel, Baxter, Deerfield, IL, USA) and biological glue. BioGlue (CryoLife, Kennesaw, GA, USA) is a two-component glue, containing engineered bovine albumin in one tube and a glutaraldehyde solution in the other. When the two substances mix, the glutaraldehyde cross-links albumin molecules to each other and to the surrounding proteins. Glutaraldehyde cross-linking resembles a peptide bond, and hence can easily form covalent bonds among proteins in contact with the chemical. When a porous implant is used, the albumin infiltrates through the pores as it gets cross-linked, resulting in strong biocompatible chemical bonding of the implant to the surrounding tissues. The use of biological glues and sealants is particularly useful when implant stability is in question, yet the surgical exposure is inadequate for complete rigid fixation (often because the globe should only be retracted gently and carefully).

MEDIAL WALL FRACTURES

Medial wall blowout fractures are common but historically were under-diagnosed because they can be asymptomatic in the acute post-traumatic phase.4, 65 The nearly ubiquitous use of CT scanning in the United States in the evaluation of facial fractures has made the diagnosis of medial fractures much easier.82 However, when CT is unavailable, the evaluating physician must maintain a high level of suspicion. Epistaxis can be associated with medial wall fractures because of tears in the sinus mucosa. The epistaxis is typically self-limited. Visionthreatening orbital hemorrhage can occur if the anterior or posterior ethmoidal vessels are injured. It is important to remind patients to avoid blowing their nose, since this can lead to orbital emphysema and a compartment syndrome (Figures 17.16A and

B).43, 83

The thin lamina papyracea constitutes most of the medial wall of the orbit, behind the posterior lacrimal crest. The medial orbital wall is completed posteriorly by the lesser wing of the sphenoid, and anteriorly by the lacrimal bone. Both the sphenoid and the lacrimal bones are thicker. Hence, medial wall fractures occur because of the weakness of the thin lamina papyracea, and are typically localized at the boundary between the lamina papyracea and one of the thicker bones. Medial wall fractures commonly occur in the context of orbital floor blowout fractures, but can also occur in isolation.4, 26 They can also be associated with nasal fractures, which can lead to

Figures 17.16A and B: Orbital/periorbital emphysema. Monocular patient was assaulted with a blow to the left orbit. He presented to the emergency department after blowing his nose, leading to severe pain and reduced vision. In the ER, his intraocular pressure was measured at 60 mm Hg. Emergent lateral canthotomy and inferior cantholysis were performed, resulting in decompression of the orbit, restoration of vision and rapid decline in intraocular pressure to the teens. A CT scan following the cantholysis revealed air in the orbit. His lateral canthus was repaired 4 days later

telecanthus and possible damage to the nasolacrimal drainage apparatus.84, 85

Described approaches to the medial wall fracture include a Lynch incision in the medial canthus, a bicoronal incision, a medial upper lid crease incision, or a transconjunctival incision. However, our preferred approach is the transcaruncular incision.8688 When the medial wall fracture is large, or associated with a floor fracture, multiple incisions may be necessary, such as a secondary lower lid fornix incision.26, 89

The transcaruncular approach requires meticulous hemostasis in order to properly expose and visualize the fracture,. Pinpoint cautery with a micro-dissection needle (e.g. Colorado needle, Colorado Biomedical, Evergreen, CO, USA) is very helpful, as is the use of thrombin solution, absorbable gelatin sponge (Gelfoam, Pfizer), FloSeal (a combination of gelatin foam and thrombin, Baxter) or 3% hydrogen peroxide solution. Care must be taken with hydrogen peroxide, since it can inhibit tissue healing, and its use has been associated with air embolization.

Good lighting is also important, and a head-mounted light source is nearly always used in our cases.

Prior to initiating surgical repair, forced ductions are performed to assess for muscle entrapment

Orbital Fractures 237

(Figure 17.7). The transcaruncular approach begins with infiltration of the medial fornix with local anesthetic containing 1:100,000 dilution of epinephrine. An incision is made through the caruncle anterior to the plica semilunaris using Westcott scissors.86, 87 The incision is extended superiorly and inferiorly along the conjunctival fornices in order to create sufficient exposure and prevent uncontrolled tearing of the conjunctiva intraoperatively. A sufficient distance away from the canaliculi is maintained. Curved Stevens tenotomy scissors are then used to bluntly dissect along Horner's muscle, which inserts on the posterior lacrimal crest. Care must be taken not to iatrogenically fracture the lamina papyracea just posterior to the crest, since this will make subsequent elevation of the periorbita more challenging. Once the posterior crest is exposed, the periorbita is incised with a monopolar unit and a microdissection needle. Achieving excellent hemostasis is critical at this point. Next, a Freer elevator is used to lift the periorbita anteriorly in order to fully expose the posterior lacrimal crest. The periorbita is then lifted posteriorly to create a subperiosteal dissection plane along the lamina papyracea (Figures 17.17A and B). The anterior ethmoidal neurovascular bundle is typically found approximately 24 mm posterior to the posterior lacrimal crest, along the fronto-ethmoidal suture line. This neurovascular bundle is carefully and thoroughly cauterized with a bipolar cautery unit, and then divided with the monopolar unit. The subperiosteal dissection is then completed to fully expose the fracture.

Figure 17.17A: Transcaruncular exposure of the left medial wall following disinsertion of the inferior oblique muscle

Figure 17.17B: Inferior oblique isolation. The IO muscle may be tagged with 6-0 polyglactin sutures and the origin disinserted to provide good exposure

238 Surgical Atlas of Orbital Diseases

If the fracture is very posterior, the posterior ethmoidal bundle may be encountered. In such cases, the posterior ethmoidal bundle should be carefully cauterized with the bipolar cautery to avoid intraor postoperative hemorrhaging. The posterior bundle is typically found approximately 12 mm from the anterior bundle, and on average only 6 mm from the optic canal.

After adequate hemostasis and exposure are achieved, herniated orbital tissues are retrieved and repositioned into the orbit. The fracture size is measured, and implant properly sized. We have found Teflon implant sizers to be very useful at this step. The implant is then placed over the fracture, ensuring that no orbital tissues are left incarcerated. When using a Medpor Barrier plate, the barrier side should be turned toward the orbit to reduce the risk of tissue scarring to the implant.

If the fracture extends inferiorly to involve the orbital floor, an inferior fornix transconjunctival incision can be made to increase exposure. At times, the inferior oblique muscle must be disinserted from its origin. At the end of the case, the oblique is then reapproximated to its origin with 6-0 polyglactin suture. The floor and medial wall fractures can be repaired with a single implant. For this, the Medpor TITAN Barrier implant is ideal, since it can be molded into the required semi-cylindrical shape and will maintain this shape. Such a large implant is better placed through the inferior fornix incision, and then the positioning adjusted through the caruncular incision. Some surgeons advocate multiple implants that can overlap, using very thin implants.26

Closing the transcaruncular incision involves placing one to three buried interrupted 6-0 fastabsorbing plain gut sutures to close the caruncular conjunctiva.

Medial wall fractures are particularly challenging to repair when they are part of a comminuted nasoethmoid fracture.93 In these circumstances, posttraumatic telecanthus is common, and can be quite disfiguring (Figure 17.9). Repair of the fractured posterior lacrimal crest and stabilization of the medial canthal tendon should be attempted during primary repair. Good exposure is critical, and when the nasoethmoid fractures are part of panfacial trauma, a bicoronal approach has many merits.94 Transnasal wiring has been described for the repair of post-

traumatic telecanthus,93, 95 and may be necessary in combination with miniplate fixation when repairing severely comminuted naso-ethmoid fractures. However, whenever possible, we favor miniplate fixation of the comminuted bones and the medial canthal tendon (Figures 17.10A and B).96

LATERAL WALL AND

ZYGOMATICO MAXILLARY

FRACTURES

Fractures of the lateral wall of the orbit are common, and typically result from direct blunt trauma to the zygoma and lateral orbital rim. The zygoma articulates with the sphenoid, maxillary, frontal and temporal bones. Therefore, fractures of the zygoma can often disrupt the architecture of the entire region, and hence are often referred to as zygomaticomalar complex fractures (ZMC fractures). Importantly, the orbital floor is always fractured in the context of a displaced zygomatic fracture, but will typically reduce once the zygoma fracture is reduced.65

Numerous surgical approaches to the ZMC fracture have been described for open reduction, including transconjunctival,78, 97-99 intraoral,100 temporal (Gillies), brow incision and bicoronal flap. In addition, some surgeons advocate closed reduction or observation for non-comminuted and uncomplicated zygoma fractures.101, 102 The approach to the ZMC fracture is greatly aided by careful evaluation of the CT scan, and different classification systems have been proposed in an effort to provide guidance to proper preoperative planning. Whichever approach is chosen, a reduction of the zygoma should attempt to replace the zygoma back into its normal anatomic location. Because the zygoma can rotate around an axis formed by the inferolateral orbital rim, reduction of just the fronto-zygomatic and zygomatico-maxillary sutures is not sufficient: a third point of alignment should be confirmed in order to ensure proper reduction and avoid late enophthalmos.65 Exploration of the lateral floor of the orbit can greatly assist in the fracture reduction, as well as help avoid orbital tissue incarceration between the zygoma and the sphenoid bones.

When non-comminuted fracture displacement is noted on examination and CT scans, we favor surgical exploration and repair through a subconjunctival

inferior fornix and lateral canthotomy approach.99 First, forced ductions are performed to assess for possible muscle entrapment. The lateral canthus and inferior fornix are infiltrated with local anesthetic containing 1:100,000 dilution of epinephrine, and a lubricated plastic corneal protective shield is placed on the eye. A lateral canthotomy and inferior cantholysis (and sometimes superior cantholysis, too), are performed to release the lateral canthal attachments and provide good exposure of the lateral rim. The lateral inferior fornix is then incised to reveal the inferolateral rim. The periosteum is incised along the entire exposed rim, and a freer elevator is used to lift the periosteum and expose the rim from above the fronto-zygomatic suture down to below the maxillo-zygomatic suture and medially to the infraorbital canal. When a depressed floor fracture is present, the inferior fornix incision can be carried out medially to provide full exposure of the floor.

Next, the zygoma must be properly reduced and aligned along three points: the fronto-zygomatic suture, the maxillo-zygomatic suture at the inferior rim, and a third point that can be the zygomaticsphenoid suture at the lateral orbital floor, the zygomatico-maxillary buttress, and/or the zygomatic arch.65, 69, 70, 99 The first two points ensure anterior alignment, whereas a third point ensures posterior alignment. Failure to achieve posterior alignment can predispose to enophthalmos by enlarging the posterior orbital volume (Figure 17.8).

A useful tool in ZMC fracture alignment has been the T-bar screw, also known as the Carroll-Girard screw (Walter Lorenz Surgical, Jacksonville, FL, USA).99, 103 This cork-screw-like instrument is screwed onto the thick bone at the malar eminence and used to manipulate the zygoma into proper position (Figure 17.18A and B). This tool is particularly useful in minimally-comminuted fractures, and allows for exceptional control of the zygoma through a smallincision approach. However, when severe comminution exists without solid bone for placement of the screw, multiple incisions would be required to achieve complete reduction and rigid fixation.

Following reduction of the fracture, fixation is accomplished using titanium miniplates. Forced ductions are performed again to ensure that no entrapment was caused by the fracture reduction. The lateral floor is explored to assess the zygomatico-

Orbital Fractures 239

Figures 17.18A and B: The Carroll-Girard (T-bar) screw is a powerful tool for 3-dimensional control and manipulation of the zygomatic or maxillary bones during orbital fracture repair. After drilling a small guidance hole, the screw is positioned and attached to the T bar

(Photos courtesy of Benjamin Marcus, MD, University of Wisconsin)

sphenoid suture. Next, the periosteum is sutured and the lower lid retractors are reapproximated using buried interrupted 7-0 polyglactin suture. The lateral canthal tendon is resuspended to the periosteum at Whitnall's tubercle. If lower lid laxity is present, horizontal tightening is performed to reduce the risk of postoperative lower lid retraction. Placement of a Frost suture can be done in the presence of concomitant lower lid trauma and when the risk of cicatricial ectropion is felt to be high.

LATE AND SECONDARY

FRACTURE REPAIR

As far back as 1957, Smith and Regan made the point that "late cases are far more difficult to correct."74 Nevertheless, thirty years ago, many surgeons advocated observation and delay of surgery for all but the most severe orbital fractures.104, 105 However, with the advent of CT scanning, an evolution in implants and fixation devices, and greatly improved surgical techniques, primary repair has become the standard of care for symptomatic or large orbital fractures. Still, there are occasions when late repair of orbital fractures is still encountered. Some reasons include lack of access to medical care following trauma, misdiagnosis, multiple medical problems preventing timely repair, or a suboptimal repair that requires reoperation.

The goal of late fracture repair is the same as for early repair, namely to restore orbital anatomy and reduce or eliminate any symptoms. Late repair is nearly always complicated by significant fibrosis and abnormal anatomy that can distort the normal anatomic landmarks. When dysmotility is a significant symptom and its repair a main goal of the operation,

240 Surgical Atlas of Orbital Diseases

good motility measurements are critical, as is the assistance of an expert in adult strabismus. Dysmotility that results from entrapment can be corrected when the muscle entrapment is reduced. However, if the dysmotility is the result of irreversible muscle or nerve damage, further orbital surgery will not restore normal motility, and can cause a significant increase in orbital fibrosis in addition to the risk of an unnecessary orbital surgery. Instead, strabismus surgery would be a better option. Hence, careful diagnosis of the underlying cause of dysmotility is crucial. In our practice, we will obtain a CT scan to evaluate the bony anatomy, and occasionally a dynamic MRI scan to evaluate the cause of dysmotility. In addition, we request a consultation from an expert in strabismus, and employ a teamoriented approach to caring for these patients.

A common reason for late surgical repair is severe enophthalmos (Figure 17.11). In a paper by Koo et al. (2006),64 clinically apparent enophthalmos was found when enophthalmos was measured at 3-4 mm or more. In such cases, patients must weigh their symptoms against the risks of surgical complications. It is important to emphasize that counseling and managing expectations are very important for achieving a result that is satisfactory to both the surgeon and the patient.

Our approach to enophthalmos repair stresses pre-operative counseling in order to clearly define what the patient desires and what we believe can be accomplished safely. Our surgical technique emphasizes good exposure, optimized illumination, and meticulous hemostasis. We employ the same incisions that we utilize for early fracture repair, namely the inferior fornix, lateral canthotomy/ cantholysis, and transcaruncular incisions. Often, the main decision is whether to attempt reduction of a healed fracture or to focus on the enophthalmos and provide orbital volume augmentation through the use of porous polyethylene implants. Given the added risk of re-fracturing and reducing healed fractures, we usually opt for orbital volume enhancement and accept the mild deformities that may be associated with poorly positioned but healed ZMC fractures. For volume enhancement, we typically utilize porous polyethylene wedge implants that are shaped to reduce orbital volume or implants with titanium that can be fixated at the orbital rim (Figure 17.19).

Figure 17.19: Medpor wedge implant. Orbital volume enhancement will often require placement of space-occupying implants. The Medpor wedge implant, which comes in both right-sided and left-sided configurations, is a useful tool. Alternatively, multiple flat implants can be stacked to achieve the appropriate amount of volume augmentation

CONCLUSION

Orbital fractures are commonly encountered by the ophathlmologist, otolaryngologist, and orbitofacial plastic surgeon. Proper treatment requires a complete ophthalmic evaluation, systematic review of the radiographic evidence, and thoughtful surgical planning with careful attention to anatomic principles. The use of smaller and hidden incisions (particularly conjunctival incisions) has made surgical treatment of orbital fractures more esthetically satisfying while reducing the risk of complications. The choice of implant materials has never been greater, providing the surgeon with options that can be tailored to the needs of the patients. While surgical repair of orbital fractures has advanced considerably over the past 50 years, there is no doubt that we will continue to see innovations and further improvements in surgical techniques, to the continued benefit of our patients.

REFERENCES

1.Zide BM and Jelks GW, Surgical Anatomy of the Orbit. (1st ed). 1985: Lippincott Williams & Wilkins 88.

2.Morriss-Kay GM. Derivation of the mammalian skull vault. J Anat 2001;199:143-51.

3.Manson PN, Hoopes JE, and Su CT. Structural pillars of the facial skeleton: an approach to the management of Le Fort fractures. Plast Reconstr Surg 1980;66:54-62.

4.Burm JS, Chung CH, and Oh SJ. Pure orbital blowout fracture: new concepts and importance of medial orbital blowout fracture. Plast Reconstr Surg 1999;103:1839-49.

5.Sorni M, Guarinos J, and Penarrocha M. Implants in anatomical buttresses of the upper jaw. Med Oral Patol Oral Cir Bucal 2005;10:163-8.

6.Kreutziger KL. Complex maxillofacial fractures: management and surgical procedures. South Med J 1982; 75:783-93.

7.Karlan MS and Cassisi NJ. Fractures of the zygoma. A geometric, biomechanical, and surgical analysis. Arch Otolaryngol 1979;105:320-7.

8.Gruss JS and Mackinnon SE. Complex maxillary fractures: role of buttress reconstruction and immediate bone grafts. Plast Reconstr Surg 1986;78:9-22.

9.Hopper RA, Salemy S, and Sze RW. Diagnosis of midface fractures with CT: what the surgeon needs to know. Radiographics 2006;26:783-93.

10.Kim JW, Goldberg RA, and Shorr N. The inferomedial orbital strut: an anatomic and radiographic study. Ophthal Plast Reconstr Surg 2002;18:355-64.

11.Goldberg RA, Shorr N, and Cohen MS. The medial orbital strut in the prevention of postdecompression dystopia in dysthyroid ophthalmopathy. Ophthal Plast Reconstr Surg 1992; 8: 32-4.

12.Rubin PA, Hatton MP, and Bilyk JR. Orbital perforating branch of the infraorbital artery: an important landmark in orbital surgery. Ophthal Plast Reconstr Surg 2005; 21: 447-9.

13.Koornneef L. Orbital septa: anatomy and function. Ophthalmology 1979; 86: 876-80.

14.Koornneef L and Zonneveld FW. Orbital anatomy, the direct scanning of the orbit in three planes and their bearings on the treatment of motility disturbances of the eye after orbital "blow-out" fractures. Acta Morphol Neerl Scand 1985; 23: 229-46.

15.Yung CW, Moorthy RS, Lindley D, et al. Efficacy of lateral canthotomy and cantholysis in orbital hemorrhage. Ophthal Plast Reconstr Surg 1994; 10: 137-41.

16.Burkat CN and Lemke BN. Retrobulbar hemorrhage: inferolateral anterior orbitotomy for emergent management. Arch Ophthalmol 2005; 123: 1260-2.

17.Schuknecht B and Graetz K. Radiologic assessment of maxillofacial, mandibular, and skull base trauma. Eur Radiol 2005; 15: 560-8.

18.Hawes MJ and Dortzbach RK. Surgery on orbital floor fractures. Influence of time of repair and fracture size. Ophthalmology 1983; 90: 1066-70.

19.Wolfe SA. Autogenous bone grafts versus alloplastic material in maxillofacial surgery. Clin Plast Surg 1982; 9: 539-40.

20.Rubin PA, Bilyk JR, and Shore JW. Orbital reconstruction using porous polyethylene sheets. Ophthalmology 1994; 101: 1697-708.

21.Ozturk S, Sengezer M, Isik S, et al. Long-term outcomes of ultra-thin porous polyethylene implants used for reconstruction of orbital floor defects. J Craniofac Surg 2005; 16: 973-7.

22.Villarreal PM, Monje F, Morillo AJ, et al. Porous polyethylene implants in orbital floor reconstruction. Plast Reconstr Surg 2002; 109: 877-85; discussion 886-7.

Orbital Fractures 241

23.Gear AJ, Lokeh A, Aldridge JH, et al. Safety of titanium mesh for orbital reconstruction. Ann Plast Surg 2002; 48: 1-7; discussion 7-9.

24.Ellis E, 3rd and Tan Y. Assessment of internal orbital reconstructions for pure blowout fractures: cranial bone grafts versus titanium mesh. J Oral Maxillofac Surg 2003;

61:442-53.

25.Nguyen PN and Sullivan P. Advances in the management of orbital fractures. Clin Plast Surg 1992; 19: 87-98.

26.Su GW and Harris GJ. Combined inferior and medial surgical approaches and overlapping thin implants for orbital floor and medial wall fractures. Ophthal Plast Reconstr Surg 2006; 22: 420-3.

27.Custer PL, Lind A, and Trinkaus KM. Complications of supramid orbital implants. Ophthal Plast Reconstr Surg 2003; 19: 62-7.

28.Choi JC, Sims CD, Casanova R, et al. Porous polyethylene implant for orbital wall reconstruction. J Craniomaxillofac Trauma 1995; 1: 42-9.

29.Bilyk JR, Rubin PA, and Shore JW. Correction of enophthalmos with porous polyethylene implants. Int Ophthalmol Clin 1992; 32: 151-6.

30.Romano JJ, Iliff NT, and Manson PN. Use of Medpor porous polyethylene implants in 140 patients with facial fractures. J Craniofac Surg 1993; 4: 142-7.

31.Choi JC, Bstandig S, Iwamoto MA, et al. Porous polyethylene sheet implant with a barrier surface: a rabbit study. Ophthal Plast Reconstr Surg 1998; 14: 32-6.

32.Tessier P, Kawamoto H, Matthews D, et al. Autogenous bone grafts and bone substitutes--tools and techniques: I. A 20,000-case experience in maxillofacial and craniofacial surgery. Plast Reconstr Surg 2005; 116: 6S-24S; discussion 92S-94S.

33.Tessier P. Autogenous bone grafts taken from the calvarium for facial and cranial applications. Clin Plast Surg 1982; 9: 531-8.

34.Kusiak JF, Zins JE, and Whitaker LA. The early revascularization of membranous bone. Plast Reconstr Surg 1985; 76: 510-6.

35.Zins JE and Whitaker LA. Membranous versus endochondral bone: implications for craniofacial reconstruction. Plast Reconstr Surg 1983; 72: 778-85.

36.Craft PD and Sargent LA. Membranous bone healing and techniques in calvarial bone grafting. Clin Plast Surg 1989;

16:11-9.

37.Kline RM, Jr. and Wolfe SA. Complications associated with the harvesting of cranial bone grafts. Plast Reconstr Surg 1995; 95: 5-13; discussion 14-20.

38.Jackson IT, Adham M, Bite U, and Marx R. Update on cranial bone grafts in craniofacial surgery. Ann Plast Surg 1987;

18:37-40.

39.Jackson IT, Costanzo C, Marsh WR, and Adham M. Orbital expansion in plagiocephaly. Br J Plast Surg 1988; 41: 16-9.

40.Zins JE, Weinzweig N, and Hahn J. A simple fail-safe method for the harvesting of cranial bone. Plast Reconstr Surg 1995;

96:1444-7.

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41.Kontio RK, Laine P, Salo A, et al. Reconstruction of internal orbital wall fracture with iliac crest free bone graft: clinical, computed tomography, and magnetic resonance imaging follow-up study. Plast Reconstr Surg 2006; 118: 1365-74.

42.Holck DE and Ng JD, Eds. Evaluation and Treatment of Orbital Fractures: A Multidisciplinary Approach. (1st ed.) 2005, Saunders. 544.

43.Reeves DL, Lucarelli MJ, and Rose JG, Jr. Severe subcutaneous emphysema following orbital blowout fracture. Ophthal Plast Reconstr Surg 2005; 21: 465-7.

44.Messina BA. Herbal supplements: Facts and myths--talking to your patients about herbal supplements. J Perianesth Nurs 2006; 21: 268-78; quiz 279-81.

45.Ang-Lee MK, Moss J, and Yuan CS. Herbal medicines and perioperative care. Jama 2001; 286: 208-16.

46.Ben Simon GJ, Bush S, Selva D, and McNab AA. Orbital cellulitis: a rare complication after orbital blowout fracture. Ophthalmology 2005; 112: 2030-4.

47.Martin B and Ghosh A. Antibiotics in orbital floor fractures. Emerg Med J 2003; 20: 66.

48.Westfall CT and Shore JW. Isolated fractures of the orbital floor: risk of infection and the role of antibiotic prophylaxis. Ophthalmic Surg 1991; 22: 409-11.

49.Miles BA, Potter JK, and Ellis E, 3rd. The efficacy of postoperative antibiotic regimens in the open treatment of mandibular fractures: a prospective randomized trial. J Oral Maxillofac Surg 2006; 64: 576-82.

50.Classen DC, Evans RS, Pestotnik SL, et al. The timing of prophylactic administration of antibiotics and the risk of surgical-wound infection. N Engl J Med 1992; 326: 281-6.

51.Flood TR, McManners J, el-Attar A, and Moos KF. Randomized prospective study of the influence of steroids on postoperative eye-opening after exploration of the orbital floor. Br J Oral Maxillofac Surg 1999; 37: 312-5.

52.Millman AL, Della Rocca RC, Spector S, et al. Steroids and orbital blowout fractures–a new systematic concept in medical management and surgical decision-making. Adv Ophthalmic Plast Reconstr Surg 1987; 6: 291-300.

53.Courtney DJ, Thomas S, and Whitfield PH. Isolated orbital blowout fractures: survey and review. Br J Oral Maxillofac Surg 2000; 38: 496-504.

54.Jordan DR, Allen LH, White J, et al. Intervention within days for some orbital floor fractures: the white-eyed blowout. Ophthal Plast Reconstr Surg 1998; 14: 379-90.

55.Koltai PJ, Amjad I, Meyer D, and Feustel PJ. Orbital fractures in children. Arch Otolaryngol Head Neck Surg 1995; 121: 1375-9.

56.Chandler DB and Rubin PA. Developments in the understanding and management of pediatric orbital fractures. Int Ophthalmol Clin 2001; 41: 87-104.

57.Hatton MP, Watkins LM, and Rubin PA. Orbital fractures in children. Ophthal Plast Reconstr Surg 2001; 17: 174-9.

58.Egbert JE, May K, Kersten RC, and Kulwin DR. Pediatric orbital floor fracture: direct extraocular muscle involvement. Ophthalmology 2000; 107: 1875-9.

59.Bansagi ZC and Meyer DR. Internal orbital fractures in the pediatric age group: characterization and management. Ophthalmology 2000; 107: 829-36.

60.Burnstine MA. Clinical recommendations for repair of isolated orbital floor fractures: an evidence-based analysis. Ophthalmology 2002; 109: 1207-10; discussion 1210-1; quiz 1212-3.

61.Grant JH, 3rd, Patrinely JR, Weiss AH, et al. Trapdoor fracture of the orbit in a pediatric population. Plast Reconstr Surg 2002; 109: 482-9; discussion 490-5.

62.Mauriello JA, Jr. Complications of orbital trauma surgery. Adv Ophthalmic Plast Reconstr Surg 1987; 7: 99-115.

63.Jordan DR, St Onge P, Anderson RL, et al. Complications associated with alloplastic implants used in orbital fracture repair. Ophthalmology 1992; 99: 1600-8.

64.Koo L, Hatton MP, and Rubin PA. When is enophthalmos "significant"? Ophthal Plast Reconstr Surg 2006; 22: 274-7.

65.Pearl RM. Treatment of enophthalmos. Clin Plast Surg 1992; 19: 99-111.

66.Cooper WC. A method for volume determination of the orbit and its contents by high resolution axial tomography and quantitative digital image analysis. Trans Am Ophthalmol Soc 1985; 83: 546-609.

67.Raskin EM, Millman AL, Lubkin V, et al. Prediction of late enophthalmos by volumetric analysis of orbital fractures. Ophthal Plast Reconstr Surg 1998; 14: 19-26.

68.Fan X, Li J, Zhu J, et al. Computer-assisted orbital volume measurement in the surgical correction of late enophthalmos caused by blowout fractures. Ophthal Plast Reconstr Surg 2003; 19: 207-11.

69.Rohner D, Tay A, Meng CS, et al. The sphenozygomatic suture as a key site for osteosynthesis of the orbitozygomatic complex in panfacial fractures: a biomechanical study in human cadavers based on clinical practice. Plast Reconstr Surg 2002; 110: 1463-71; discussion 1472-5.

70.Gruss JS, Van Wyck L, Phillips JH, and Antonyshyn O. The importance of the zygomatic arch in complex midfacial fracture repair and correction of posttraumatic orbitozygomatic deformities. Plast Reconstr Surg 1990; 85: 878-90.

71.Burnstine MA. Clinical recommendations for repair of orbital facial fractures. Curr Opin Ophthalmol 2003; 14: 236-40.

72.Boush GA and Lemke BN. Progressive infraorbital nerve hypesthesia as a primary indication for blow-out fracture repair. Ophthal Plast Reconstr Surg 1994; 10: 271-5.

73.Anderson AG, Frank TW, and Loftus JM. Fractures of the medial infraorbital rim. Arch Otolaryngol Head Neck Surg 1988; 114: 1461-3.

74.Smith B and Regan WF, Jr. Blow-out fracture of the orbit; mechanism and correction of internal orbital fracture. Am J Ophthalmol 1957; 44: 733-9.

75.Converse JM, Smith B, Obear MF, and Wood-Smith D. Orbital blowout fractures: a ten-year survey. Plast Reconstr Surg 1967; 39: 20-36.