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Reconstruction of orbital wall defects: critical review of 72 patients
Int. J. Oral Maxillofac. Surg. 2007; 36: 193–199 doi:10.1016/j.ijom.2006.11.002, available online at http://www.sciencedirect.com
Leading Clinical Paper Trauma
Reconstruction of orbital wall defects: critical review of 72 patients
C. Jaquie´ry1, C. Aeppli1, P. Cornelius2, A. Palmowsky3, C. Kunz1, B. Hammer4 1 Clinic for Reconstructive Surgery, Maxillofacial Unit, University Hospital, Basel, Switzerland; 2Maxillofacial Unit, Bundeswehrkrankenhaus, Ulm, Germany; 3 Eye Clinic, University Hospital, Basel, Switzerland; 4Craniofacial Center Hirslanden, Aarau, Switzerland
C. Jaquie´ry, C. Aeppli, P. Cornelius, A. Palmowsky, C. Kunz, B. Hammer: Reconstruction of orbital wall defects: critical review of 72 patients. Int. J. Oral Maxillofac. Surg. 2007; 36: 193–199. # 2006 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved. Abstract. Between January 1996 and December 2001, 72 out of 354 patients were included in a retrospective study analysing the outcome of repaired orbital wall defects. Selection was dependent on the availability of pre and postoperative CT scans and on ophthalmologic examination. In particular, orthoptical assessment was performed up to 1 year after operation. In 72 patients, 83 orbital wall defects were analysed and allocated to one of five categories. Accuracy and type of reconstruction were assessed in unilateral orbital wall defects (n = 61) and compared with functional outcome. Reconstruction was performed by using PDS membrane (39%), calvarian bone (13%), titanium mesh (7%) or a combination of these materials (37%). Postoperatively, 91% of the patients had normal vision without double images within 208 at every gaze. Accuracy of reconstruction correlated with severity of orbital injury and functional outcome. Functional outcome between category II and III fractures showed no significant difference. The medial margin of the lateral infraorbital fissure being preserved (category II fracture) facilitates reconstruction technically. Accuracy of orbital reconstruction is one important factor to obtain best functional outcome, but other determinants like displacement and/or atrophy of intramuscular cone fat should be considered.
Orbital fractures are common facial injuries6. They usually occur in the context of zygomatic-orbital fractures, as pure blow-out fractures or are part of panfacial injuries. If the size of the orbital defect is considered to be functionally relevant and reconstruction is indicated, best functional and cosmetic results can be obtained with early revision and repair 9. Reconstruction of orbital defects has to be preceded by reposition and rigid fixation of the orbital rim and 0901-5027/030193 + 07 $30.00/0
the zygomatic complex, in order to achieve an intact outer facial frame 10. Meticulous dissection back into the posterior orbit until uninjured areas are reached is crucial and establishes the basis for further reconstruction12. It has been previously reported that enlargement and deformation of the orbit give rise to visible enophthalmos2,21. As a consequence, disturbance of eye motility together with double images is likely to occur. The severity of an orbital trauma
Key words: orbital defects; orbital reconstruction; functional outcome; Harms’ tangent screen. Accepted for publication 8 November 2006
is not only dependent on the size of a defect and the number of orbital walls involved, but also on the localization of the defect and any technical difficulties during surgical repair. Defects of the anterior part of the orbital floor only slightly influence the position of the globe, whereas defects within the postero-medial wall may lead to relapse of the orbital content resulting in enophthalmos 13. Surgically, a defect of the orbital floor with intact medial
# 2006 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
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Table 1. Classification of orbital wall defects Category Category I Category II Category III Category IV Category V
Description Isolated defect of the orbital floor or the medial wall, 1–2 cm2, within zones 1 and 2 Defect of the orbital floor and/or of the medial wall, >2 cm2, within zones 1 and 2 Defect of the orbital floor and/or of the medial wall, >2 cm2, within zones 1 and 2 Defect of the entire orbital floor and the medial wall, extending into the posterior third (zone 3) Same as IV, defect extending into the orbital roof
border of the lateral infraorbital fissure can easily be repaired, the angle between orbital floor and lateral wall being preserved. Lack of this anatomical landmark increases technical difficulties and compromises the accuracy of reconstruction. The aim of the present study was the critical analysis of 83 orbital fractures considering (i) size of defect, (ii) localization of defect and (iii) distinct anatomical landmarks involved, all of which determine the technical demands during surgical repair. The strategy of reconstruction (surgical approach, one or a combination of different materials used) was dependent on the results of the preoperative analysis of the defect. Ophthalmological outcome was assessed quantitatively and compared with accuracy of orbital reconstruction.
Note
Bony ledge preserved at the medial margin of the infraorbital fissure Missing bony ledge medial to the infraorbital fissure Missing bony ledge medial to the infraorbital fissure
the defect in the two-dimensional orbital sketch. Patient data
Between January 1996 and December 2001 a total of 354 patients were operated in the clinic for reconstructive surgery, maxillofacial unit, University Hospital Basel, following orbital fractures. Of these, 72 (17 females, 65 males) could be included in the retrospective study. Patient inclusion was dependent on the following criteria: (i) preoperative
and postoperative CT scans (axial and coronal sections), (ii) detailed surgeon’s report on the reconstruction and materials used, (iii) preoperative and postoperative ophthalmologic examination and postoperative ophthalmologic follow up, until no further improvement of double vision could be achieved. Mean age at time of surgery was 39 years (range 13–82) and mean follow-up time was 4.3 years (2–9). On an average of 2.8 days after trauma (0–30) the patients were operated on by a maxillofacial surgeon. The different reasons for orbital trauma
Patients and methods Classification of orbital wall defects
Due to the complex three-dimensional osseous structure of the internal orbit, a clinically relevant description of orbital fractures including different sizes of defects cannot be achieved without simplification. It was therefore decided to use a two-dimensional model, aiming to visualize the missing third dimension and display the volume-relevant areas. By de-folding a three-dimensional orbital model, a trefoil-like orbital scheme can be obtained. Using this diagram, most orbital defects can be described and evaluated semi-quantitatively (Fig. 1). Defects of the lateral wall were not considered, for the reasons discussed below. A detailed description of the classification of orbital defects is shown in Table 1 and illustrated in (Figs. 2–6). Two experienced maxillofacial surgeons independently assigned the fracture and defect pattern of every patient to one of the five categories, using preoperative computed tomographic (CT) scans (axial and coronal sections), and depicted the extent and localization of
Fig. 1. Left and right orbital sketch: (1) orbital floor, anterior third, (2) orbital floor, middle third, (3) orbital floor, dorsal third, (4) infraorbital fissure, (5) supraorbital fissure, (6) optical nerve, (7) lateral wall, (8) nasal–lachrymal duct, (9) medial border of the infraorbital fissure.
Fig. 2. Orbital wall defects, category I. Schematic depiction of defects and corresponding coronal section of CT scan. Borders of defect are marked by arrows.
195
Orbital wall defects
Fig. 3. Orbital wall defects, category II. (a) Schematic depiction of defects, (b) corresponding coronal section of CT scan, and (c) orbital model visualizing extent and topography of a middle-sized defect. Preserved bony ledge of the infraorbital fissure marked by arrow.
Fig. 4. Orbital wall defects, category III (see legend to Fig. 3; missing bony ledge of the infraorbital fissure marked by arrow).
are listed in Table 2. In 72 patients, a total of 83 fractures were treated. From each patient’s history the following data were extracted:
Fig. 5. Orbital wall defects, category IV (see legend to Fig. 2).
- type of incision (low mid-eyelid incision, lateral canthothomy, upper blepharoblasty incision, coronal approach); - pattern of the fracture, especially whether the lateral wall of the orbit was involved or not; - type of material used for reconstruction (bone grafts, resorbable membrane (PDS, Ethicon, Germany), titanium meshes (orbital plate, Synthes, Switzerland)). Assessment of reconstruction
Accuracy of unilateral reconstruction (n = 61) was assessed according to ELLIS & TAN7 using selected coronal sections of Table 2. Orbital fracture: social context of the trauma (n = 72) Reason
Fig. 6. Orbital wall defects, category V (see legend to Fig. 2).
Number
Percentage
Traffic Sports Fall Job Violence
20 17 13 11 11
28 24 18 15 15
Total
72
100
196
Jaquie´ry et al. Table 3. Distribution of orbital fractures (n = 83) Category
Number
Percentage
I II III IV V
4 34 34 4 7
5 41 41 5 8
Total
83
100
Table 4. Fractures with displacement of the lateral wall (n = 83) I
II
III
IV
V
0/4
1/34
6/34
3/4
6/7
Table 5. Fractures where coronal approaches were used (n = 83) I Fig. 7. Harms’ tangent screen. This depicts a quantitative assessment of binocular single vision. The clear area marks the area of binocular single vision, the striped background the area of binocular double vision. This example shows double vision in up-gaze starting from 208 within a lateral view of 208 and double vision in down-gaze starting from 308 within a lateral view of 308.
0/4
II
III
IV
V
1/34
5/34
4/4
7/7
examination was performed prior to surgery. In addition to impaired vision, presence of double vision was examined quantitatively using the Harms’ tangent screen (Fig. 7). After reconstruction, the patients were followed up orthoptically until no further improvement of vision could be observed. In general, a stable ophthalmologic situation was achieved after 9–12 months of observation. Results
Fig. 8. Reconstructed orbital wall defect (category III). Postoperative CT (coronal section) showing reconstruction of orbital wall defect (category III) using titanium mesh (""). As compared to the unaffected side, the level of the reconstructed orbital floor is lower, due to the fact that the medial margin of the infraorbital fissure as an anatomical landmark is missing. This may result in visible enophthalmos and functional disorders (double images).
postoperative CT scans. The quality of reconstruction was considered to be ideal (3), satisfactory (2) or poor (1). In particular, the transition between the medial wall and the orbital floor as well as the transition between floor and lateral wall was evaluated at three distinct localizations (i.e. directly dorsal to the orbital rim, in the middle of the reconstructed area and slightly anterior to the end of the reconstruction) and compared with the unaffected contra-lateral orbit. For each
reconstruction the mean of the three assessments was taken for further evaluation. Ophthalmologic examination
All 72 patients were assessed ophthalmologically. If both orbits were fractured (n = 11), the patient was assigned to the fracture site with the ‘higher’ category. Depending on the patient’s compliance, an ophthalmologic or, if possible, orthoptic
In 72 patients, 83 orbital wall fractures could be evaluated. The distribution of the fractures is listed in Table 3. Accurate reduction of the lateral wall is a prerequisite for adequate orbital reconstruction. Involvement of the lateral wall is described in Table 4. Many orbital fractures can be managed by local approaches, but if the defect involves more than the entire floor (category III) a coronal approach may be required. The number of coronal approaches as a fraction of the total number of operated fractures in each category is listed in Table 5. Material used for reconstruction
Three different types of material were used for reconstruction of orbital wall defects (Fig. 8): bone grafts harvested from the calvaria (tabula externa), titanium meshes and resorbable membranes. The use of these materials, as well as a combination of autologous bone grafts and alloplastic material, is described in Table 6.
Orbital wall defects Table 6. Materials used for reconstruction (n = 83) I (n = 4) No material PDS Titanium meshes Bone Bone + PDS/Ti mesh
II (n = 34)
III (n = 34)
IV (n = 4)
V (n = 7)
10/34 5/34 7/34 7/34
16/34 1/34 4/34 13/34
4/4
7/7
3/4 1/4
Table 7. Assessment of reconstruction (n = 61) I (n = 3) 3
II (n = 24)
III (n = 30)
2.73
IV (n = 1)
V (n = 3)
3
2.22
2.37
Table 8. Ophthalmologic examination, post-traumatic (n = 72) No examination No double vision No double vision within 208 No double vision within 108 Double vision at all gaze Amaurosis
I (n = 3)
II (n = 29)
III (n = 31)
IV (n = 3)
V (n = 6)
3/3
10/29 10/29 6/29 2/29 1/29
11/31 13/31 2/31 1/31 2/31 2/31
2/3
3/6 2/6
1/3
1/6
197
was followed up orthoptically. Out of 72 patients 47 (65%) had normal vision without double images at any gaze (ideal). Using the Harm’s tangent screen, normal vision up to 208 (good) was assessed in 19 (26%) and normal vision up to 108 (satisfactory) in 4 (5%) patients. Impaired vision was present in three additional patients, who recovered completely during the observation period. In another two patients elevation of the globe within the operated orbit, together with eye motility disturbance and double images, was noticed. Magnetic resonance imaging (MRI) and CT scans revealed inflammation related thickening of the soft tissue around the PDS sheeting (Fig. 9). Total recovery of vision and eye motility within 6 months could be observed in both patients. Presence and degree of postoperative double vision are summarized in Table 9. Enophthalmos, defined as more than 2 mm of difference in projection measured by exophthalmometry 18, was found in only 4 (5%) out of 72 patients.
Discussion
Fig. 9. Soft-tissue inflammation around PDS sheeting. Postoperative MRI (coronal section) showing thickening of the tissue around the PDS sheeting, which corresponds to soft-tissue inflammation (arrows).
Accuracy of reconstruction
Ophthalmologic examination
Assessment of orbital reconstruction is summarized in Table 7. Almost ideal reconstruction could be observed for category II defects (2.73 out of 3 scores). Due to technical difficulties during surgical repair, reconstruction of category III defects was less accurate (2.37 out of 3 scores). But even in category V fractures, satisfactory results could be achieved (2.22 out of 3 scores).
Prior to surgery 44 (61%) out of 72 patients could be examined. Normal vision without double images was assessed in 25 (35%) of the patients. Due to rupture of the globe (n = 2) and injured optical nerve (n = 2), four patients suffered from amaurosis of the affected eye. Presence and degree of post-traumatic double vision are summarized in Table 8. Postoperatively, every patient
The aim of this report was to critically review the outcome of 72 patients with 83 orbital fractures considering (i) extent and severity of the defect, (ii) the difficulty and technical demands during surgical repair, (iii) accuracy of reconstruction, and (iv) degree of functional and morphological disorders in long-term follow up. Selection of patients was dependent on the availability of preoperative and postoperative clinical and radiological data. In particular, a postoperative orthoptical examination was performed in order to quantitatively assess functional outcome. The question as to whether or not orbital wall defects of limited size should be operated on and reconstructed is not discussed here. More than 80% of the orbital wall fractures assessed were allocated to category II (n = 34) or III (n = 34). These types of fractures, involving the orbital floor and the medial wall, are mainly caused by indirect and blunt high-energy trauma and are encountered frequently 14,25.
Table 9. Ophthalmologic examination, postoperative (n = 72) No double vision (ideal) No double vision within 208 (good) No double vision within 108 (satisfactory) Double vision at all gaze (poor) Amaurosis
I (n = 3)
II (n = 29)
3/3)
17/29 12/29
III (n = 31)
IV (n = 3)
V (n = 6)
22/31 6/31 1/31
1/3 1/3
2/6 1/6 2/6
2/31
1/3
1/6
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The incidence of complex and comminuted orbital fractures, represented by categories IV (n = 4) and V (n = 7), has been dramatically decreased by airbag deployment 5. Displacement of the lateral wall of the orbit
As shown in Table 4, involvement of the lateral wall is dependent on the complexity of injury to the zygomatic complex and should be classified separately from defects of the orbital walls. Anatomical repositioning of the zygomatic complex restores the continuity of the lateral wall. Every reconstruction of an orbital defect should be preceded by proper reduction and fixation of a zygomatic complex fracture. In category III fractures displacement of the lateral wall was found in 18% (6/34) whereas in category II fractures it was found in 3% (1/34) only. Functional outcome (Table 9) showed no significant difference between category II and III fractures. This suggests that involvement of the lateral wall does not increase the difficulty of repairing an orbital wall defect. Coronal approach
Operating on pan-facial fractures, the use of a coronal approach together with local incisions is unquestioned in order to entirely expose every fracture line and subsequently define the sequence of repair 3,10 . Concomitant injury (i.e. skull-base fracture) may influence the technique of surgical exposition, especially if the repair of the fractures and revision of the skull base can be carried out simultaneously. A coronal incision facilitates access to the upper half of the whole orbit and may be required even in a middle-sized defect of the medial wall (category II), under the condition that the defect is localized in the upper and dorsal part of the medial wall 22. Category II and III fractures generally can be managed by local approaches (Table 5). It has previously been demonstrated that most postoperative complications in the context of pan-facial injuries are due to insufficient exposure and inadequate reposition and fixation of fractures 11. This supports the importance of thorough and meticulous exposure as well as accurate repair of orbital wall defects. Reconstruction of orbital wall defects
Anatomical reconstruction of the entire orbit is a prerequisite of normal position and motility of the eye. Defects less than
1 cm2 and localized anteriorly of the equator of the eye ball were surgically exposed and revised but not repaired. Defects of the orbital floor and the medial wall of limited size were managed by resorbable membranes like PDS sheeting 4. Reconstruction of larger defects requires a stable material in order to support the orbital content and to prevent the risk of secondary enophthalmos24. MRI and CT scans of two patients whose orbits were repaired by using the flexible PDS sheeting only showed the presence of fibrotic scar tissue around the membrane followed by functional disorders (reduced eye motility, double vision) (Fig. 9)17. For reconstruction of middle-sized defects (II and III), the PDS sheeting was replaced by a nonresorbable polyethylene membrane (Medpor1, Porex, Surgical Inc., USA) in order to avoid inflammatory reactions during degradation19, and by using rigid titanium meshes where support of the orbital content was needed 7. Complex orbital fractures required in general more than one material for reconstruction (Table 6). After thorough dissection of the orbital content, flexible PDS sheeting was placed around the peri-orbital tissue in order to protect the soft tissue during reconstruction and to facilitate accurate placement of reconstructive material. After completion of reconstruction this sheeting was usually left in place. Titanium meshes or larger autologous bone grafts were used to provide stability; additional bone chips were introduced to fill up gaps and to tune projection by comparing the reconstruction with the unaffected orbit. Cranial bone grafts were preferentially used as they are easy to harvest 26, and remain stable and preserve their volume if adequately fixed 16. The choice of material (alloplastic or autologous, or a combination of both) is essentially dependent on the size and localization of the defect. With correct use, complications of orbital reconstruction are not material related, as demonstrated by ELLIS & TAN7. In terms of anatomical accuracy, titanium meshes may be favoured over autologous bone grafts, but functionally no significant differences were found 7. Placement of a single reconstructive piece (cranial bone graft or titanium mesh) to repair a large defect (III, IV or V) is often restricted by limited access to the internal orbit and bears the risk of iatrogenic damage to periorbital tissue. Precise reconstitution of orbital volume and ‘tuning’ of projection can more easily be achieved by using more than one piece of reconstructive material. As recently demonstrated8, computer-assisted surgery (CAS) may be a
helpful tool in the context of orbital reconstruction. This technique enables the surgeon to virtually plan the reconstruction and pre-form alloplastic material to be used intraoperatively. The reconstruction can be checked immediately, if CT is available during the operation. CAS may shorten the time required for orbital repair and possibly improve the quality of reconstruction, but cannot replace a surgeon’s experience. Ophthalmologic examination
Injuries of the orbit are frequently combined with impaired vision (double images) due to reduced eye motility caused by hematoma, ischemia of the eye muscles, and entrapment of orbital soft tissue as well as nerve injuries1,17. Defect-dependent enlargement of the orbital volume together with traumainduced atrophy of the periorbital tissue leads to relapse of the eyeball within the orbit and to visible enophthalmos followed again by disturbed motility of the affected eye 23. Postoperatively, enophthalmos was found in only 4 (5%) out of 72 patients and was therefore not an issue in this study. Extent of reduced eye motility can be related to the degree of orbital destruction 15. More important from a functional point of view is the ability of the patient to achieve binocular single vision, the area of which can be measured using the Harms’ tangent screen. In Switzerland, driving of a motor vehicle may be permitted if drivers have double-image free vision of at least 208 at every gaze. Examination of binocular single vision using the Harms’ tangent screen requires cooperation of the patient; hence, due to the severity of the trauma it was not possible to measure the degree of binocular single vision in every patient preoperatively. Follow up within 12 months (Table 9) demonstrates that, with increasing complexity of the orbital fracture, reduced binocular single vision can be expected. Within the category II and III fractures, only one patient was left with binocular single vision of equal to or less than 108. Interestingly, no significant difference between functional outcomes of category II and III fractures could be found, although reconstruction of category III fractures was technically more demanding and the result less accurate. Apart from precise reconstruction of shape and volume of the bony orbit2, postoperative disturbance of eye motility including enophthalmos could also be due to displacement and/or atrophy of intramuscular cone fat20. This additional
Orbital wall defects aspect should not be underestimated and may contribute to the functional outcomes observed in this study. In conclusion, best functional and cosmetic results of functionally relevant orbital defect fractures can be achieved by early revision and repair. Small and middle-sized defects (categories I, II and III) can be repaired using a single material only, whereas reconstruction of complex orbital defect fractures requires in general a combination of different materials. Accuracy of reconstruction is a prerequisite for anatomical positioning of the eyeball in order to prevent functional disorders. Postoperative functional (disturbed eye motility) and morphological (enophthalmos) disorders are also influenced by displacement and/or atrophy of periorbital soft tissue. Acknowledgements. The authors would like to thank Peter Bucher and Stephan de Maddalena for photographic work up.
References 1. Burnstine MA. Clinical recommendations for repair of isolated orbital floor fractures: an evidence-based analysis. Ophthalmology 2002: 109: 1207–1210 discussion 1210-1201; quiz 1212-1203. 2. Cunningham LL, Peterson GP, Haug RH. The relationship between enophthalmos, linear displacement, and volume change in experimentally recreated orbital fractures. J Oral Maxillofac Surg 2005: 63: 1169–1173. 3. Dempf R, Hausamen JE. Fractures of the facial skull. Unfallchirurg 2000: 103: 301–313. 4. Dietz A, Ziegler CM, Dacho A, Althof F, Conradt C, Kolling G, von Boehmer H, Steffen H. Effectiveness of a new perforated 0.15 mm poly-pdioxanon-foil versus titanium-dynamic mesh in reconstruction of the orbital floor. J Craniomaxillofac Surg 2001: 29: 82–88. 5. Duma SM, Jernigan MV. The effects of airbags on orbital fracture patterns in frontal automobile crashes. Ophthal Plast Reconstr Surg 2003: 19: 107–111. 6. Ellis 3rd E, el-Attar A, Moos KF. An analysis of 2067 cases of zygomaticoorbital fracture. J Oral Maxillofac Surg 1985: 43: 417–428.
7. Ellis 3rd E, Tan Y. Assessment of internal orbital reconstructions for pure blowout fractures: cranial bone grafts versus titanium mesh. J Oral Maxillofac Surg 2003: 61: 442–453. 8. Gellrich NC, Schramm A, Hammer B, Rojas S, Cufi D, Lagreze W, Schmelzeisen R. Computer-assisted secondary reconstruction of unilateral posttraumatic orbital deformity. Plast Reconstr Surg 2002: 110: 1417–1429. 9. Girotto JA, MacKenzie E, Fowler C, Redett R, Robertson B, Manson PN. Long-term physical impairment and functional outcomes after complex facial fractures. Plast Reconstr Surg 2001: 108(2):312–327. 10. Gruss JS, Bubak PJ, Egbert MA. Craniofacial fractures. An algorithm to optimize results. Clin Plast Surg 1992: 19: 195–206. 11. Gruss JS, Whelan MF, Rand RP, Ellenbogen RG. Lessons learnt from the management of 1500 complex facial fractures. Ann Acad Med Singapore 1999: 28: 677–686. 12. Hammer B. Orbital Fractures: Diagnosis, Operative Treatment, Secondary Corrections. Seattle: Hogrefe & Huber Publishers 1995. 13. Hammer B, Prein J. Correction of posttraumatic orbital deformities: operative techniques and review of 26 patients. J Craniomaxillofac Surg 1995: 23: 81–90. 14. Haug RH, Van Sickels JE, Jenkins WS. Demographics and treatment options for orbital roof fractures. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2002: 93: 238–246. 15. Jank S, Schuchter B, Strobl H, Emshoff R, Baldissera I, Nicasi A, Norer B. Post-traumatic ocular motility in orbital floor fractures. Mund Kiefer Gesichtschir 2003: 7: 19–24. 16. Kelly CP, Cohen AJ, Yavuzer R, Jackson IT. Cranial bone grafting for orbital reconstruction: is it still the best? J Craniofac Surg 2005: 16: 181–185. 17. Kontio R, Suuronen R, Salonen O, Paukku P, Konttinen YT, Lindqvist C. Effectiveness of operative treatment of internal orbital wall fracture with polydioxanone implant. Int J Oral Maxillofac Surg 2001: 30: 278–285. 18. Lahbabi M, Lockhart R, Fleuridas G, Chikhani L, Bertrand JC, Guilbert F. Post-traumatic enophthalmos. Physiopathologic considerations and current therapeutics. Rev Stomatol Chir Maxillofac 1999: 100: 165–174.
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19. Lee S, Maronian N, Most SP, Whipple ME, McCulloch TM, Stanley RB, Farwell DG. Porous high-density polyethylene for orbital reconstruction. Arch Otolaryngol Head Neck Surg 2005: 131: 446–450. 20. Manson PN, Clifford CM, Su CT, Iliff NT, Morgan R. Mechanisms of global support and post-traumatic enophthalmos: I. The anatomy of the ligament sling and its relation to intramuscular cone orbital fat. Plast Reconstr Surg 1986: 77: 193–202. 21. Manson PN, Grivas A, Rosenbaum A, Vannier M, Zinreich J, Iliff N. Studies on enophthalmos: II. The measurement of orbital injuries and their treatment by quantitative computed tomography. Plast Reconstr Surg 1986: 77: 203–214. 22. Marin PC, Love T, Carpenter R, Iliff NT, Manson PN. Complications of orbital reconstruction: misplacement of bone grafts within the intramuscular cone. Plast Reconstr Surg 1998: 101: 1323– 1327 discussion 1328-1329. 23. Meyer C, Groos N, Sabatier H, Wilk A. Long-term outcome of surgically treated orbital floor fractures. Apropos of a series of 242 patients. Rev Stomatol Chir Maxillofac 1998: 99: 149–154. 24. Potter JK, Ellis E. Biomaterials for reconstruction of the internal orbit. J Oral Maxillofac Surg 2004: 62: 1280–1297. 25. Shere JL, Boole JR, Holtel MR, Amoroso PJ. An analysis of 3599 midfacial and 1141 orbital blowout fractures among 4426 United States Army Soldiers, 1980–2000. Otolaryngol Head Neck Surg 2004: 130: 164–170. 26. Tessier P, Kawamoto H, Posnick J, Raulo Y, Tulasne JF, Wolfe SA. Taking calvarial grafts, either split in situ or splitting of the parietal bone flap ex vivo—tools and techniques: V. A 9650case experience in craniofacial and maxillofacial surgery. Plast Reconstr Surg 2005: 116: 54S–71S discussion 92S-94S. Address: Claude Jaquie´ry Clinic for Reconstructive Surgery Maxillofacial Unit University Hospital Spitalstrasse 21 CH – 4031 Basel Switzerland Tel: +41 61 265 73 40; Fax: +41 61 265 74 58 E-mail: [email protected]
Leading Clinical Paper Trauma
Reconstruction of orbital wall defects: critical review of 72 patients
C. Jaquie´ry1, C. Aeppli1, P. Cornelius2, A. Palmowsky3, C. Kunz1, B. Hammer4 1 Clinic for Reconstructive Surgery, Maxillofacial Unit, University Hospital, Basel, Switzerland; 2Maxillofacial Unit, Bundeswehrkrankenhaus, Ulm, Germany; 3 Eye Clinic, University Hospital, Basel, Switzerland; 4Craniofacial Center Hirslanden, Aarau, Switzerland
C. Jaquie´ry, C. Aeppli, P. Cornelius, A. Palmowsky, C. Kunz, B. Hammer: Reconstruction of orbital wall defects: critical review of 72 patients. Int. J. Oral Maxillofac. Surg. 2007; 36: 193–199. # 2006 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved. Abstract. Between January 1996 and December 2001, 72 out of 354 patients were included in a retrospective study analysing the outcome of repaired orbital wall defects. Selection was dependent on the availability of pre and postoperative CT scans and on ophthalmologic examination. In particular, orthoptical assessment was performed up to 1 year after operation. In 72 patients, 83 orbital wall defects were analysed and allocated to one of five categories. Accuracy and type of reconstruction were assessed in unilateral orbital wall defects (n = 61) and compared with functional outcome. Reconstruction was performed by using PDS membrane (39%), calvarian bone (13%), titanium mesh (7%) or a combination of these materials (37%). Postoperatively, 91% of the patients had normal vision without double images within 208 at every gaze. Accuracy of reconstruction correlated with severity of orbital injury and functional outcome. Functional outcome between category II and III fractures showed no significant difference. The medial margin of the lateral infraorbital fissure being preserved (category II fracture) facilitates reconstruction technically. Accuracy of orbital reconstruction is one important factor to obtain best functional outcome, but other determinants like displacement and/or atrophy of intramuscular cone fat should be considered.
Orbital fractures are common facial injuries6. They usually occur in the context of zygomatic-orbital fractures, as pure blow-out fractures or are part of panfacial injuries. If the size of the orbital defect is considered to be functionally relevant and reconstruction is indicated, best functional and cosmetic results can be obtained with early revision and repair 9. Reconstruction of orbital defects has to be preceded by reposition and rigid fixation of the orbital rim and 0901-5027/030193 + 07 $30.00/0
the zygomatic complex, in order to achieve an intact outer facial frame 10. Meticulous dissection back into the posterior orbit until uninjured areas are reached is crucial and establishes the basis for further reconstruction12. It has been previously reported that enlargement and deformation of the orbit give rise to visible enophthalmos2,21. As a consequence, disturbance of eye motility together with double images is likely to occur. The severity of an orbital trauma
Key words: orbital defects; orbital reconstruction; functional outcome; Harms’ tangent screen. Accepted for publication 8 November 2006
is not only dependent on the size of a defect and the number of orbital walls involved, but also on the localization of the defect and any technical difficulties during surgical repair. Defects of the anterior part of the orbital floor only slightly influence the position of the globe, whereas defects within the postero-medial wall may lead to relapse of the orbital content resulting in enophthalmos 13. Surgically, a defect of the orbital floor with intact medial
# 2006 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
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Table 1. Classification of orbital wall defects Category Category I Category II Category III Category IV Category V
Description Isolated defect of the orbital floor or the medial wall, 1–2 cm2, within zones 1 and 2 Defect of the orbital floor and/or of the medial wall, >2 cm2, within zones 1 and 2 Defect of the orbital floor and/or of the medial wall, >2 cm2, within zones 1 and 2 Defect of the entire orbital floor and the medial wall, extending into the posterior third (zone 3) Same as IV, defect extending into the orbital roof
border of the lateral infraorbital fissure can easily be repaired, the angle between orbital floor and lateral wall being preserved. Lack of this anatomical landmark increases technical difficulties and compromises the accuracy of reconstruction. The aim of the present study was the critical analysis of 83 orbital fractures considering (i) size of defect, (ii) localization of defect and (iii) distinct anatomical landmarks involved, all of which determine the technical demands during surgical repair. The strategy of reconstruction (surgical approach, one or a combination of different materials used) was dependent on the results of the preoperative analysis of the defect. Ophthalmological outcome was assessed quantitatively and compared with accuracy of orbital reconstruction.
Note
Bony ledge preserved at the medial margin of the infraorbital fissure Missing bony ledge medial to the infraorbital fissure Missing bony ledge medial to the infraorbital fissure
the defect in the two-dimensional orbital sketch. Patient data
Between January 1996 and December 2001 a total of 354 patients were operated in the clinic for reconstructive surgery, maxillofacial unit, University Hospital Basel, following orbital fractures. Of these, 72 (17 females, 65 males) could be included in the retrospective study. Patient inclusion was dependent on the following criteria: (i) preoperative
and postoperative CT scans (axial and coronal sections), (ii) detailed surgeon’s report on the reconstruction and materials used, (iii) preoperative and postoperative ophthalmologic examination and postoperative ophthalmologic follow up, until no further improvement of double vision could be achieved. Mean age at time of surgery was 39 years (range 13–82) and mean follow-up time was 4.3 years (2–9). On an average of 2.8 days after trauma (0–30) the patients were operated on by a maxillofacial surgeon. The different reasons for orbital trauma
Patients and methods Classification of orbital wall defects
Due to the complex three-dimensional osseous structure of the internal orbit, a clinically relevant description of orbital fractures including different sizes of defects cannot be achieved without simplification. It was therefore decided to use a two-dimensional model, aiming to visualize the missing third dimension and display the volume-relevant areas. By de-folding a three-dimensional orbital model, a trefoil-like orbital scheme can be obtained. Using this diagram, most orbital defects can be described and evaluated semi-quantitatively (Fig. 1). Defects of the lateral wall were not considered, for the reasons discussed below. A detailed description of the classification of orbital defects is shown in Table 1 and illustrated in (Figs. 2–6). Two experienced maxillofacial surgeons independently assigned the fracture and defect pattern of every patient to one of the five categories, using preoperative computed tomographic (CT) scans (axial and coronal sections), and depicted the extent and localization of
Fig. 1. Left and right orbital sketch: (1) orbital floor, anterior third, (2) orbital floor, middle third, (3) orbital floor, dorsal third, (4) infraorbital fissure, (5) supraorbital fissure, (6) optical nerve, (7) lateral wall, (8) nasal–lachrymal duct, (9) medial border of the infraorbital fissure.
Fig. 2. Orbital wall defects, category I. Schematic depiction of defects and corresponding coronal section of CT scan. Borders of defect are marked by arrows.
195
Orbital wall defects
Fig. 3. Orbital wall defects, category II. (a) Schematic depiction of defects, (b) corresponding coronal section of CT scan, and (c) orbital model visualizing extent and topography of a middle-sized defect. Preserved bony ledge of the infraorbital fissure marked by arrow.
Fig. 4. Orbital wall defects, category III (see legend to Fig. 3; missing bony ledge of the infraorbital fissure marked by arrow).
are listed in Table 2. In 72 patients, a total of 83 fractures were treated. From each patient’s history the following data were extracted:
Fig. 5. Orbital wall defects, category IV (see legend to Fig. 2).
- type of incision (low mid-eyelid incision, lateral canthothomy, upper blepharoblasty incision, coronal approach); - pattern of the fracture, especially whether the lateral wall of the orbit was involved or not; - type of material used for reconstruction (bone grafts, resorbable membrane (PDS, Ethicon, Germany), titanium meshes (orbital plate, Synthes, Switzerland)). Assessment of reconstruction
Accuracy of unilateral reconstruction (n = 61) was assessed according to ELLIS & TAN7 using selected coronal sections of Table 2. Orbital fracture: social context of the trauma (n = 72) Reason
Fig. 6. Orbital wall defects, category V (see legend to Fig. 2).
Number
Percentage
Traffic Sports Fall Job Violence
20 17 13 11 11
28 24 18 15 15
Total
72
100
196
Jaquie´ry et al. Table 3. Distribution of orbital fractures (n = 83) Category
Number
Percentage
I II III IV V
4 34 34 4 7
5 41 41 5 8
Total
83
100
Table 4. Fractures with displacement of the lateral wall (n = 83) I
II
III
IV
V
0/4
1/34
6/34
3/4
6/7
Table 5. Fractures where coronal approaches were used (n = 83) I Fig. 7. Harms’ tangent screen. This depicts a quantitative assessment of binocular single vision. The clear area marks the area of binocular single vision, the striped background the area of binocular double vision. This example shows double vision in up-gaze starting from 208 within a lateral view of 208 and double vision in down-gaze starting from 308 within a lateral view of 308.
0/4
II
III
IV
V
1/34
5/34
4/4
7/7
examination was performed prior to surgery. In addition to impaired vision, presence of double vision was examined quantitatively using the Harms’ tangent screen (Fig. 7). After reconstruction, the patients were followed up orthoptically until no further improvement of vision could be observed. In general, a stable ophthalmologic situation was achieved after 9–12 months of observation. Results
Fig. 8. Reconstructed orbital wall defect (category III). Postoperative CT (coronal section) showing reconstruction of orbital wall defect (category III) using titanium mesh (""). As compared to the unaffected side, the level of the reconstructed orbital floor is lower, due to the fact that the medial margin of the infraorbital fissure as an anatomical landmark is missing. This may result in visible enophthalmos and functional disorders (double images).
postoperative CT scans. The quality of reconstruction was considered to be ideal (3), satisfactory (2) or poor (1). In particular, the transition between the medial wall and the orbital floor as well as the transition between floor and lateral wall was evaluated at three distinct localizations (i.e. directly dorsal to the orbital rim, in the middle of the reconstructed area and slightly anterior to the end of the reconstruction) and compared with the unaffected contra-lateral orbit. For each
reconstruction the mean of the three assessments was taken for further evaluation. Ophthalmologic examination
All 72 patients were assessed ophthalmologically. If both orbits were fractured (n = 11), the patient was assigned to the fracture site with the ‘higher’ category. Depending on the patient’s compliance, an ophthalmologic or, if possible, orthoptic
In 72 patients, 83 orbital wall fractures could be evaluated. The distribution of the fractures is listed in Table 3. Accurate reduction of the lateral wall is a prerequisite for adequate orbital reconstruction. Involvement of the lateral wall is described in Table 4. Many orbital fractures can be managed by local approaches, but if the defect involves more than the entire floor (category III) a coronal approach may be required. The number of coronal approaches as a fraction of the total number of operated fractures in each category is listed in Table 5. Material used for reconstruction
Three different types of material were used for reconstruction of orbital wall defects (Fig. 8): bone grafts harvested from the calvaria (tabula externa), titanium meshes and resorbable membranes. The use of these materials, as well as a combination of autologous bone grafts and alloplastic material, is described in Table 6.
Orbital wall defects Table 6. Materials used for reconstruction (n = 83) I (n = 4) No material PDS Titanium meshes Bone Bone + PDS/Ti mesh
II (n = 34)
III (n = 34)
IV (n = 4)
V (n = 7)
10/34 5/34 7/34 7/34
16/34 1/34 4/34 13/34
4/4
7/7
3/4 1/4
Table 7. Assessment of reconstruction (n = 61) I (n = 3) 3
II (n = 24)
III (n = 30)
2.73
IV (n = 1)
V (n = 3)
3
2.22
2.37
Table 8. Ophthalmologic examination, post-traumatic (n = 72) No examination No double vision No double vision within 208 No double vision within 108 Double vision at all gaze Amaurosis
I (n = 3)
II (n = 29)
III (n = 31)
IV (n = 3)
V (n = 6)
3/3
10/29 10/29 6/29 2/29 1/29
11/31 13/31 2/31 1/31 2/31 2/31
2/3
3/6 2/6
1/3
1/6
197
was followed up orthoptically. Out of 72 patients 47 (65%) had normal vision without double images at any gaze (ideal). Using the Harm’s tangent screen, normal vision up to 208 (good) was assessed in 19 (26%) and normal vision up to 108 (satisfactory) in 4 (5%) patients. Impaired vision was present in three additional patients, who recovered completely during the observation period. In another two patients elevation of the globe within the operated orbit, together with eye motility disturbance and double images, was noticed. Magnetic resonance imaging (MRI) and CT scans revealed inflammation related thickening of the soft tissue around the PDS sheeting (Fig. 9). Total recovery of vision and eye motility within 6 months could be observed in both patients. Presence and degree of postoperative double vision are summarized in Table 9. Enophthalmos, defined as more than 2 mm of difference in projection measured by exophthalmometry 18, was found in only 4 (5%) out of 72 patients.
Discussion
Fig. 9. Soft-tissue inflammation around PDS sheeting. Postoperative MRI (coronal section) showing thickening of the tissue around the PDS sheeting, which corresponds to soft-tissue inflammation (arrows).
Accuracy of reconstruction
Ophthalmologic examination
Assessment of orbital reconstruction is summarized in Table 7. Almost ideal reconstruction could be observed for category II defects (2.73 out of 3 scores). Due to technical difficulties during surgical repair, reconstruction of category III defects was less accurate (2.37 out of 3 scores). But even in category V fractures, satisfactory results could be achieved (2.22 out of 3 scores).
Prior to surgery 44 (61%) out of 72 patients could be examined. Normal vision without double images was assessed in 25 (35%) of the patients. Due to rupture of the globe (n = 2) and injured optical nerve (n = 2), four patients suffered from amaurosis of the affected eye. Presence and degree of post-traumatic double vision are summarized in Table 8. Postoperatively, every patient
The aim of this report was to critically review the outcome of 72 patients with 83 orbital fractures considering (i) extent and severity of the defect, (ii) the difficulty and technical demands during surgical repair, (iii) accuracy of reconstruction, and (iv) degree of functional and morphological disorders in long-term follow up. Selection of patients was dependent on the availability of preoperative and postoperative clinical and radiological data. In particular, a postoperative orthoptical examination was performed in order to quantitatively assess functional outcome. The question as to whether or not orbital wall defects of limited size should be operated on and reconstructed is not discussed here. More than 80% of the orbital wall fractures assessed were allocated to category II (n = 34) or III (n = 34). These types of fractures, involving the orbital floor and the medial wall, are mainly caused by indirect and blunt high-energy trauma and are encountered frequently 14,25.
Table 9. Ophthalmologic examination, postoperative (n = 72) No double vision (ideal) No double vision within 208 (good) No double vision within 108 (satisfactory) Double vision at all gaze (poor) Amaurosis
I (n = 3)
II (n = 29)
3/3)
17/29 12/29
III (n = 31)
IV (n = 3)
V (n = 6)
22/31 6/31 1/31
1/3 1/3
2/6 1/6 2/6
2/31
1/3
1/6
198
Jaquie´ry et al.
The incidence of complex and comminuted orbital fractures, represented by categories IV (n = 4) and V (n = 7), has been dramatically decreased by airbag deployment 5. Displacement of the lateral wall of the orbit
As shown in Table 4, involvement of the lateral wall is dependent on the complexity of injury to the zygomatic complex and should be classified separately from defects of the orbital walls. Anatomical repositioning of the zygomatic complex restores the continuity of the lateral wall. Every reconstruction of an orbital defect should be preceded by proper reduction and fixation of a zygomatic complex fracture. In category III fractures displacement of the lateral wall was found in 18% (6/34) whereas in category II fractures it was found in 3% (1/34) only. Functional outcome (Table 9) showed no significant difference between category II and III fractures. This suggests that involvement of the lateral wall does not increase the difficulty of repairing an orbital wall defect. Coronal approach
Operating on pan-facial fractures, the use of a coronal approach together with local incisions is unquestioned in order to entirely expose every fracture line and subsequently define the sequence of repair 3,10 . Concomitant injury (i.e. skull-base fracture) may influence the technique of surgical exposition, especially if the repair of the fractures and revision of the skull base can be carried out simultaneously. A coronal incision facilitates access to the upper half of the whole orbit and may be required even in a middle-sized defect of the medial wall (category II), under the condition that the defect is localized in the upper and dorsal part of the medial wall 22. Category II and III fractures generally can be managed by local approaches (Table 5). It has previously been demonstrated that most postoperative complications in the context of pan-facial injuries are due to insufficient exposure and inadequate reposition and fixation of fractures 11. This supports the importance of thorough and meticulous exposure as well as accurate repair of orbital wall defects. Reconstruction of orbital wall defects
Anatomical reconstruction of the entire orbit is a prerequisite of normal position and motility of the eye. Defects less than
1 cm2 and localized anteriorly of the equator of the eye ball were surgically exposed and revised but not repaired. Defects of the orbital floor and the medial wall of limited size were managed by resorbable membranes like PDS sheeting 4. Reconstruction of larger defects requires a stable material in order to support the orbital content and to prevent the risk of secondary enophthalmos24. MRI and CT scans of two patients whose orbits were repaired by using the flexible PDS sheeting only showed the presence of fibrotic scar tissue around the membrane followed by functional disorders (reduced eye motility, double vision) (Fig. 9)17. For reconstruction of middle-sized defects (II and III), the PDS sheeting was replaced by a nonresorbable polyethylene membrane (Medpor1, Porex, Surgical Inc., USA) in order to avoid inflammatory reactions during degradation19, and by using rigid titanium meshes where support of the orbital content was needed 7. Complex orbital fractures required in general more than one material for reconstruction (Table 6). After thorough dissection of the orbital content, flexible PDS sheeting was placed around the peri-orbital tissue in order to protect the soft tissue during reconstruction and to facilitate accurate placement of reconstructive material. After completion of reconstruction this sheeting was usually left in place. Titanium meshes or larger autologous bone grafts were used to provide stability; additional bone chips were introduced to fill up gaps and to tune projection by comparing the reconstruction with the unaffected orbit. Cranial bone grafts were preferentially used as they are easy to harvest 26, and remain stable and preserve their volume if adequately fixed 16. The choice of material (alloplastic or autologous, or a combination of both) is essentially dependent on the size and localization of the defect. With correct use, complications of orbital reconstruction are not material related, as demonstrated by ELLIS & TAN7. In terms of anatomical accuracy, titanium meshes may be favoured over autologous bone grafts, but functionally no significant differences were found 7. Placement of a single reconstructive piece (cranial bone graft or titanium mesh) to repair a large defect (III, IV or V) is often restricted by limited access to the internal orbit and bears the risk of iatrogenic damage to periorbital tissue. Precise reconstitution of orbital volume and ‘tuning’ of projection can more easily be achieved by using more than one piece of reconstructive material. As recently demonstrated8, computer-assisted surgery (CAS) may be a
helpful tool in the context of orbital reconstruction. This technique enables the surgeon to virtually plan the reconstruction and pre-form alloplastic material to be used intraoperatively. The reconstruction can be checked immediately, if CT is available during the operation. CAS may shorten the time required for orbital repair and possibly improve the quality of reconstruction, but cannot replace a surgeon’s experience. Ophthalmologic examination
Injuries of the orbit are frequently combined with impaired vision (double images) due to reduced eye motility caused by hematoma, ischemia of the eye muscles, and entrapment of orbital soft tissue as well as nerve injuries1,17. Defect-dependent enlargement of the orbital volume together with traumainduced atrophy of the periorbital tissue leads to relapse of the eyeball within the orbit and to visible enophthalmos followed again by disturbed motility of the affected eye 23. Postoperatively, enophthalmos was found in only 4 (5%) out of 72 patients and was therefore not an issue in this study. Extent of reduced eye motility can be related to the degree of orbital destruction 15. More important from a functional point of view is the ability of the patient to achieve binocular single vision, the area of which can be measured using the Harms’ tangent screen. In Switzerland, driving of a motor vehicle may be permitted if drivers have double-image free vision of at least 208 at every gaze. Examination of binocular single vision using the Harms’ tangent screen requires cooperation of the patient; hence, due to the severity of the trauma it was not possible to measure the degree of binocular single vision in every patient preoperatively. Follow up within 12 months (Table 9) demonstrates that, with increasing complexity of the orbital fracture, reduced binocular single vision can be expected. Within the category II and III fractures, only one patient was left with binocular single vision of equal to or less than 108. Interestingly, no significant difference between functional outcomes of category II and III fractures could be found, although reconstruction of category III fractures was technically more demanding and the result less accurate. Apart from precise reconstruction of shape and volume of the bony orbit2, postoperative disturbance of eye motility including enophthalmos could also be due to displacement and/or atrophy of intramuscular cone fat20. This additional
Orbital wall defects aspect should not be underestimated and may contribute to the functional outcomes observed in this study. In conclusion, best functional and cosmetic results of functionally relevant orbital defect fractures can be achieved by early revision and repair. Small and middle-sized defects (categories I, II and III) can be repaired using a single material only, whereas reconstruction of complex orbital defect fractures requires in general a combination of different materials. Accuracy of reconstruction is a prerequisite for anatomical positioning of the eyeball in order to prevent functional disorders. Postoperative functional (disturbed eye motility) and morphological (enophthalmos) disorders are also influenced by displacement and/or atrophy of periorbital soft tissue. Acknowledgements. The authors would like to thank Peter Bucher and Stephan de Maddalena for photographic work up.
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