Original Investigation

Surgical Timing and Postoperative Ocular Motility in Type B Orbital Blowout Fractures Janice C. Liao, M.D.*, Valerie I. Elmalem, M.D.†, Timothy S. Wells, M.D.*, and Gerald J. Harris, M.D.* *Department of Ophthalmology, Medical College of Wisconsin—The Eye Institute, Milwaukee, Wisconsin; and †Department of Ophthalmology, SUNY Downstate Medical Center, Brooklyn, New York, U.S.A.

Purpose: To determine whether patients with Type B orbital blowout fractures (soft-tissue distortion disproportionate to bone-fragment displacement) repaired within 7 days of injury have statistically greater postoperative vertical binocular fusion than similar patients who undergo later surgery. Methods: Prospective and retrospective surgical case series. Inclusion criteria were orbital floor (with or without medial wall) blowout fracture repair, preoperative coronal orbital CT scans, and patient age of at least 12 years at time of postoperative binocular visual field. Results: Twenty-five patients met inclusion criteria. Ten patients (group 1) had surgery within 7 days of injury, and 15 patients (group 2) had surgery more than 7 days after injury. The total cohort had a median postoperative vertical binocular fusion of 90°. Group 1 had postoperative vertical binocular fusion averaging 100°. Nine of 10 patients (90%) were above and 1 of 10 (10%) were below the median for the entire cohort. Group 2 had postoperative vertical binocular fusion averaging 70°. Three of 15 patients (20%) were above and 12 of 15 patients (80%) were below the median for the entire cohort. The difference between the average postoperative vertical binocular fusion of the 2 groups was statistically significant by two-tailed unpaired t test with p value 0.0022. Conclusions: Patients with Type B orbital blowout fractures (soft-tissue distortion disproportionate to bone-fragment displacement) have statistically greater average postoperative vertical binocular fusion if repaired within 7 days of injury than similar patients who undergo later surgery. (Ophthal Plast Reconstr Surg 2015;31:29–33)

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rbital blowout fractures are frequent sequelae of blunt facial trauma. They may involve herniation of orbital soft tissues—fat, connective tissue, or extraocular muscle—through the fracture opening, with resulting entrapment or compression.1,2 Soft-tissue damage can ultimately lead to muscular or perimuscular fibrosis, with limited motility and disabling diplopia in adults or amblyopia in children. The indications and optimal timing for surgical repair have been debated for decades, and controversy continues. Accepted for publication January 28, 2014. Partially supported by an unrestricted grant from Research to Prevent Blindness, Inc., New York, NY. Poster presentation at ASOPRS 44th Annual Fall Scientific Symposium, November 15, 2013, New Orleans, LA. The authors have no financial or conflicts of interest to disclose. Address correspondence and reprint requests to Janice C. Liao, M.D., 925 N. 87th St., Milwaukee, WI 53226. E-mail: [email protected] DOI: 10.1097/IOP.0000000000000161

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Although some sources,3,4 including a meta-analysis of 64 publications,3 support surgery within 2 weeks for patients with significant diplopia and signs of entrapment or for large fractures that portend enophthalmos, Dal Canto and Linberg5 reported equivalent results if repairs were performed within 2 weeks or were delayed for up to 29 days. While the data provided in many published studies do not allow confirmation, the authors suspect that reported outcomes may be influenced by the fracture subtypes in each study cohort. Based on the hypothesis that ongoing compression, attenuation, and ischemia of soft tissues between bone fragments might increase late-term fibrosis, Harris et al.2 retrospectively analyzed soft-tissue distortion relative to bone-fragment separation in the preoperative CT scans of 30 blowout fractures. Fractures were broadly divided into Types A and B, based on whether these 2 features were, respectively, proportionate or disproportionate (Fig. 1). Postoperative motility was quantified with binocular visual fields (BVFs) (Fig. 2), and the range of vertical binocular fusion (VBF) among the 30 patients was ordered by degrees. Among the 15 patients with motility outcomes poorer than the median (VBF ≤ 86°), 27% had A fractures and 73% had B fractures. Among the 15 patients with outcomes better than the median (VBF ≥ 88°), 67% had A fractures and 33% had B fractures. Differences were even more pronounced away from the median VBF. In addition, although numbers were small, the data suggested that early intervention might benefit patients with B fractures. Among the 5 patients with better-than-median outcomes, 3 had surgery within the first week; among the 11 with poorer-than-median outcomes, only 1 had surgery within the first week. The current study aims to elucidate further the impact of surgical timing on Type B fractures—those with soft-tissue displacement and distortion that exceed or are disproportionate to the separation between bone fragments. The group includes pediatric trapdoor (“white-eyed blowout”)1 fractures but is not limited to that well-defined, specific syndrome.

METHODS Institutional Review Board approval was obtained from the Medical College of Wisconsin, and guidelines of the Health Insurance Portability and Accountability Act were observed. The Medical College of Wisconsin database was searched for Current Procedural Terminology code 21390 from January, 2003, to March, 2011. Records were initially reviewed for the following inclusion criteria: orbital floor (with or without medial wall) blowout fracture repair, with uniform surgical technique by either of the senior authors (G.J.H., T.S.W.); preoperative coronal CT scans of the orbit; and patient age of at least 12 years at time of the postoperative BVF. Coronal CT scans were then reviewed to identify patients with Type B orbital blowout fractures2 (Fig. 3). Patients were excluded for any

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VBF of group 1 statistically significant by two-tailed unpaired Student t test with p value 0.0097.

DISCUSSION

FIG. 1.  Schematic classification of blowout fractures, based on lesser (A) or greater (B) soft-tissue distortion relative to bone fragment configuration. Reprinted with permission from Harris et al.2

of the following criteria: inability to give informed consent; inability to perform a BVF; or amblyopia or poor vision in 1 eye precluding diplopia. BVFs, as described by Feibel and Roper-Hall,6 were performed 8 or more weeks after surgery (Fig. 2). One patient with a full BVF at 5 weeks after surgery did not return for subsequent visits. The case was included with the assumption that full motility would not diminish over time. To prevent bias, the visual field administrator was not aware of the timing of surgery relative to the orbital injury. The intervals between orbital injury and fracture repair were determined. From March, 2011, to August, 2013, new patients meeting the same inclusion criteria were prospectively enrolled. Patients with Type B fractures and postoperative BVFs managed by the authors from 1992 to 19972 were also included to increase the power of the study. Results were analyzed to determine whether subjects who underwent surgery within 7 days of injury had significantly greater postoperative VBF than those who did not. Outcomes were additionally divided into groups greater or lesser than the median VBF for the cohort. Data were analyzed for statistical significance by Student t test (significance defined as p ≤ 0.05).

RESULTS Twenty-five patients met inclusion criteria. Ten patients (group 1) had surgery within 7 days of injury (range, 0–6 days; average, 3 days; median, 4 days) (Table 1). Fifteen patients (group 2) had later surgery (range, 8–2920 days; average, 231 days; median, 14 days) (Table 2). The median postoperative VBF for the entire cohort was 90°. Group 1 had postoperative VBF averaging 100° (range, 65°–110°; median, 106.5°). Nine of 10 patients (90%) were above and 1 of 10 (10%) were below the median for the entire cohort. Group 2 had postoperative VBF averaging 70° (range, 13°–110°; median, 74°). Three of 15 patients (20%) were above and 12 of 15 patients (80%) were below the median for the entire cohort. The difference between the average postoperative VBF of group 1 and group 2 was statistically significant by 2-tailed unpaired Student t test with p value 0.0022. Within group 2, the average VBF for those patients repaired within 8 to 14 days of injury was 65°, with the difference from the average postoperative VBF of group 1 remaining statistically significant by two-tailed unpaired Student t test with p value 0.0318. In addition, if the 2 patients in group 2 with the longest time intervals to surgery were excluded, the average postoperative VBF was 73°, with the difference from the average postoperative

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The management of orbital blowout fractures has evolved since 1957 when they were first described by Smith and Regan7: from early repair in all cases recommended by those authors, to observation of all patients for 4 to 6 months (with delayed repair, if necessary) advocated by Putterman et al.8 in 1974, and to less absolute views today.2–5,9–13 However, even current management philosophies differ. Although most surgeons agree on urgent intervention for some specific conditions (i.e., entrapment causing oculovagal reflex phenomena; the pediatric “white-eyed blowout” fracture; complete globe prolapse into the maxillary sinus),1,3,8,11,12 opinions vary about more routine fractures. Some authors advocate surgery within the first 2 weeks for persistent diplopia, for large fractures, or for enophthalmos greater than 2 mm2–4,9,14; others prefer observation for more than 2 weeks to allow edema and hemorrhage to subside.4,8,9 Anatomical reduction of entrapped orbital soft tissue does not necessarily correlate with a fully normal functional outcome. As noted by Koornneef,15–17 the orbital soft tissues are interconnected by a network of fibrous septa that unite the sheaths of the inferior rectus and oblique muscles, the extraconal fibrofatty matrix, and the periosteum of the orbital floor. In an earlier study,2 the authors postulated that this connective tissue complex is variably sheared, lacerated, or crushed during the initial trauma. In addition, depending on the volume and displacement of herniated tissue and the configuration of surrounding bone fragments, there may be ongoing constriction or attenuation of the tissue and its blood supply. The net effect is late intrinsic fibrosis that can limit full excursion despite anatomically successful surgery. The authors believe that this mechanism more plausibly explains late diplopia after complete soft-tissue release than often-cited “neurogenic” injury. In the earlier study,2 the authors examined the relationship between blowout fracture configuration and motility outcome. Using preoperative CT scans to divide patients into lesser (Type A) or greater (Type B) soft-tissue distortion relative to bone-fragment displacement and using BVFs to assess late motility, they found that patients with Type B fractures were more likely to have limited VBF. Those findings prompted their interest in the relationship, if any, between the time of intervention and the late outcome. Other authors have addressed postoperative outcomes relative to surgical timing. Aggregate series suggest that repair within the first 2 weeks yields superior postoperative function in cases of significant diplopia with evidence of entrapment or in large orbital floor fractures.3 Emery et al.18 found that repair within 7 days of injury, versus 8 to 14 days, did not factor in the presence of late diplopia experienced by 24 of 49 patients evaluated 7 or more months after surgery. Hwang et al.19 found no significant difference in the incidence of diplopia 12 months after surgery among patients with preoperative diplopia who underwent surgery within 7 days (94 patients), 8 to 14 days (45 patients), or more than 14 days (14 patients) after injury. In a large series, Shin et al.10 found a significant reduction in the incidence of observer-determined motility limitation and enophthalmos among patients repaired within 1 week of injury compared with patients repaired later, but they did not find a significant reduction in the incidence of subjective diplopia when comparing the 2 groups. Ben Simon et al.13 acknowledged that surgery should be performed promptly in cases of inferior rectus entrapment but reported similar postoperative improvement

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FIG. 2.  Binocular visual field (BVF). Area of single binocular vision in a sample patient (64° vertically). Shaded area represents diplopia and depicts the full normal BVF (110° vertically) according to the format of Feibel and Roper-Hall.6 Reprinted with permission from Harris et al.2

in ocular ductions between 27 patients repaired within 2 weeks and 23 patients repaired after 2 weeks. In 2 of the foregoing studies, outcomes were examined in the context of preoperative anatomical factors. Hwang et al.19 found no difference in postsurgical diplopia between patients with initial bony defects that were less than 1 cm2, 1.1 to 2.0 cm2, 2.1 to 3.0 cm2, or greater than 3.0 cm2. Ben Simon et al.13 noted greater limitation of vertical ductions on presentation, and greater improvement in postsurgical motility, in patients with clinical and radiographic inferior rectus entrapment versus patients without evidence of entrapment. However, neither group of authors further analyzed these anatomical variables with respect to surgical timing. In this series of patients with Type B orbital blowout fractures, the authors found that repair within 7 days of injury yielded statistically better motility than later surgery, including surgery 8 to 14 days after injury. Furthermore, the average VBF in group 2 was similar and remained statistically significantly different from the average VBF of group 1, with and without the inclusion of the 2 patients with the longest intervals to surgery. This study differs from earlier investigations in 2 important respects that should be considered in interpreting and comparing the results

of such studies. First, the authors limited their focus to Type B fractures (soft-tissue distortion disproportionate to bone-fragment displacement), in which orbital tissue is arguably subject to ongoing post-injury damage. Without knowledge of blowout fracture subtypes in earlier reports, the results are difficult to interpret. For example, if a study involved a preponderance of Type A fractures (Fig. 1), with little constriction or attenuation of soft tissue, it would likely show little negative impact of delayed repair. Second, the authors quantified late ocular motility by measuring the range of VBF, which they believe allows more precise, standardized, and reproducible assessment than methods used in some other studies. Fibrosis in the inferior fibrofatty-muscular complex can limit both upgaze and downgaze. Therefore, the range in degrees through which fusion is maintained may more accurately reflect recovery than the patient’s symptomatic diplopia (which varies with individual patient activity and sensitivity) or an observer’s light-reflex estimate of vertical ductions (which varies with patient head posture). The study is limited by small sample size due to stringent inclusion criteria and variable follow up in the trauma population. However, the sample was sufficient to demonstrate statistical significance of the results.

© 2014 The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc.

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TABLE 2.  Group 2: surgical repair after 7 days of injury Case # 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

Surgical timing (days)

Vertical excursion (degrees)

8 8 8 9 9 11 13 14 44 45 53 63 80 180 2920

74 36 60 110 77 88 13 64 85 110 77 48 107 55 50

fractures warrant urgent intervention, the authors recommend that all Type B fractures be considered for repair within a few days of injury to minimize ongoing soft-tissue compromise. They acknowledge that the impact of late fibrosis will vary from 1 patient to another. Some may be left with disabling diplopia and require strabismus surgery. For others, loss of binocularity only in extreme up- or downgaze may have little clinical significance. Nevertheless, the goal should be restoration of full motility in all patients, and early intervention in selected cases can further that end. Surgical timing often depends on the time of referral, and further education of emergency physicians and primary eye care providers in distinctions among blowout fractures is encouraged. Future studies that incorporate more prospectively enrolled patients, specify fracture subtype, and quantify ocular motility will add to the understanding of timing and outcome.

REFERENCES FIG. 3. Examples of Type B blowout fractures. Top, Right trapdoor fracture with orbital soft tissue extending through narrow bone gap. Arrow indicating herniated orbital fat. Center, Herniated left orbital fat is broader than bone-fragment separation. Bottom, Marked displacement and attenuation of left orbital soft tissue.

High-resolution CT allows more discriminating evaluation of soft-tissue/bone fragment relationships in floor fractures than was available to early oculoplastic surgeons, and it is appropriate that management be refined accordingly. Although it is generally recognized that pediatric white-eyed blowout1 TABLE 1.  Group 1: surgical repair within 7 days of injury Case # 1 2 3 4 5 6 7 8 9 10

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Surgical timing (days)

Vertical excursion (degrees)

0 1 1 1 2 4 4 4 5 6

90 108 110 65 100 110 105 110 90 110

1. 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. 2. Harris GJ, Garcia GH, Logani SC, et al. Correlation of preoperative computed tomography and postoperative ocular motility in orbital blowout fractures. Ophthal Plast Reconstr Surg 2000;16:179–87. 3. 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. 4. Hawes MJ, Dortzbach RK. Surgery on orbital floor fractures. Influence of time of repair and fracture size. Ophthalmology 1983;90:1066–70. 5. Dal Canto AJ, Linberg JV. Comparison of orbital fracture repair performed within 14 days versus 15 to 29 days after trauma. Ophthal Plast Reconstr Surg 2008;24:437–43. 6. Feibel RM, Roper-Hall G. Evaluation of the field of binocular single vision in incomitant strabismus. Am J Ophthalmol 1974;78:800–5. 7. Smith B, Regan WF Jr. Blow-out fracture of the orbit; mechanism and correction of internal orbital fracture. Am J Ophthalmol 1957;44:733–9. 8. Putterman AM, Stevens T, Urist MJ. Nonsurgical management of blow-out fractures of the orbital floor. Am J Ophthalmol 1974;77:232–9. 9. Dutton JJ. Management of blow-out fractures of the orbital floor. Surv Ophthalmol 1991;35:279–80. 10. Shin JW, Lim JS, Yoo G, et al. An analysis of pure blowout fractures and associated ocular symptoms. J Craniofac Surg 2013;24:703–7. 11. Hartstein ME, Roper-Hall G. Update on orbital floor fractures: indications and timing for repair. Facial Plast Surg 2000;16:95–106.

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12. Bansagi ZC, Meyer DR. Internal orbital fractures in the pediatric age group: characterization and management. Ophthalmology 2000;107:829–36. 13. Ben Simon GJ, Syed HM, McCann JD, et al. Early versus late repair of orbital blowout fractures. Ophthalmic Surg Lasers Imaging 2009;40:141–8. 14. Biesman BS, Hornblass A, Lisman R, et al. Diplopia after surgical repair of orbital floor fractures. Ophthal Plast Reconstr Surg 1996;12:9–16; discussion 17. 15. Koornneef L. Orbital septa: anatomy and function. Ophthalmology 1979;86:876–80.

Surgical Timing in Orbital Fractures

16. Koornneef L. Anatomy and function of orbital septa. In: Berstein L, ed. Plastic Reconstructive Surgery of the Head and Neck. Vol 2. New York, NY: Grune & Stratton, 1981:130–9. 17. Koornneef L. Sectional Anatomy of the Orbit. Amsterdam: Van Gorcum; 1981. 18. Emery JM, Noorden GK, Sclernitzauer DA. Orbital floor fractures: long-term follow-up of cases with and without surgical repair. Trans Am Acad Ophthalmol Otolaryngol 1971;75: 802–12. 19. Hwang K, Huan F, Hwang PJ. Diplopia and enophthalmos in blowout fractures. J Craniofac Surg 2012;23:1077–82.

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Surgical timing and postoperative ocular motility in type B orbital blowout fractures.

To determine whether patients with Type B orbital blowout fractures (soft-tissue distortion disproportionate to bone-fragment displacement) repaired w...
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