Update on orbital trauma

The Predictive Value of Computed Tomography Findings for Poor Visual Outcome in Traumatic Eye Injury

Background. The prognosis of visual outcome is important for patients and healthcare providers and guides proper decision-making in traumatic eye injury. In this study, we have evaluated the predictive value of computed tomography (CT) scan findings for poor visual outcomes in patients with traumatic eye injuries. Methods. In a retrospective survey, documents of 200 patients with traumatic eye injury who underwent a diagnostic orbital CT scan were reviewed. Disorganized or collapsed globe, intraocular foreign body or gas, increased or decreased anterior chamber size, hemorrhage in the anterior or posterior chamber, crystalline or intraocular lens dislocation, posterior sclera thickening, globe borders haziness, orbital fracture, orbital hemorrhage, and foreign body, optic canal, and optic nerve injuries are the diagnostic clues for eye injury in CT scan. The predictive value of CT scan findings for poor visual outcome was calculated by sensitivity, specificity, accuracy, predictive values, hazard ratios, and binary logistic regression model. Results. The sensitivity, specificity, accuracy, and positive predictive values showed to be high. However, there was a low negative predictive value of CT findings for the prediction of poor vision. Among the investigated factors, disorganized/collapsed globe (HR 47.72, CI 6.13–371.62), increased/decreased anterior chamber size (HR 5.04, CI 2.57–9.88), hemorrhage in anterior/posterior chamber (HR 3.58, CI 1.900–6.774/3.62, CI 1.90–6.89), globe borders haziness (HR 3.06, CI 1.33–7.01), orbital foreign body (HR 3.66, CI 1.11–12.05), and optic canal/nerve injury (HR 21.62, CI 4.73–98.78) reached the statistical significance for increasing the hazard ratio for poor visual outcome in patients with a traumatic eye injury. Logistic regression analysis showed only evidence for disorganized/collapsed globe and optic canal/nerve injury in orbital CT scan as independent predictive factors for poor visual outcome. Conclusion. CT scan findings can be used as prognostic factors for visual outcomes in patients with a traumatic eye injury.

Outpatient Surgical Management of Orbital Blowout Fractures

There is ample investigation into the optimal timing and approach to orbital blowout fracture (OBF) repair; however, less attention has been directed toward postoperative care. This is a multicenter IRB-approved retrospective review of patients with OBF presenting to our study sites between November 2008 and August 2016. Those with isolated OBF, over 18 years of age, and who had not suffered additional facial injuries or globe trauma were included. A total of 126 surgical cases of isolated OBF repair were identified that met our inclusion and exclusion criteria; 42.1% were outpatient repairs while the remaining 57.9% were admitted for overnight monitoring. Time elapsed prior to repair differed between the two groups at a mean of 8.4 days versus 5.2 days for the outpatient and inpatient cohorts, respectively ( p  = 0.001). A majority of inpatient cases underwent immediate repair, while a majority of outpatient cases were delayed. There were two cases of RBH in the outpatient cohort resulting in an overall incidence of 1.6%. In both instances, a significant change in clinical exam including decreased visual acuity, diplopia, and eye pain prompted repeat evaluation and immediate intervention for hematoma evacuation. Estimated hospital charges to the patient's insurance for key components of an inpatient versus outpatient isolated OBF repair amounted to a total cost of $9,598.22 for inpatient management and $7,265.02 for outpatient management without reflexive postoperative imaging. Reflexive postoperative CT scans were obtained in 76.7% of inpatient cases and only two led to a reoperation. No outpatient repairs included reflexive postoperative imaging. Outpatient OBF repair is an attractive alternative to inpatient management. The potential cost savings of outpatient management of OBF, which do not detract from quality or safety of patient care, should not be ignored. Our results will hopefully contribute to updated shared practice patterns for all subspecialties that participate in the surgical management of OBF.

A Protocol to Reduce Interobserver Variability in the Computed Tomography Measurement of Orbital Floor Fractures

Orbital fracture detection and size determination from computed tomography (CT) scans affect the decision to operate, the type of surgical implant used, and postoperative outcomes. However, the lack of standardization of radiological signs often leads to the false-positive detection of orbital fractures, while nonstandardized landmarks lead to inaccurate defect measurements. We aim to design a novel protocol for CT measurement of orbital floor fractures and evaluate the interobserver variability on CT scan images. Qualitative aspects of this protocol include identifying direct and indirect signs of orbital fractures on CT scan images. Quantitative aspects of this protocol include measuring the surface area of pure orbital floor fractures using computer software. In this study, 15 independent observers without clinical experience in orbital fracture detection and measurement measured the orbital floor fractures of three randomly selected patients following the protocol. The time required for each measurement was recorded. The intraclass correlation coefficient of the surface area measurements is 0.999 (0.997-1.000) with p-value < 0.001. This suggests that any observer measuring the surface area will obtain a similar estimation of the fractured surface area. The maximum error limit was 0.901 cm(2) which is less than the margin of error of 1 cm(2) in mesh trimming for orbital reconstruction. The average duration required for each measurement was 3 minutes 19 seconds (ranging from 1 minute 35 seconds to 5 minutes). Measurements performed with our novel protocol resulted in minimal interobserver variability. This protocol is effective and generated reproducible results, is easy to teach and utilize, and its findings can be interpreted easily.

Remote penetrating orbital trauma due to a snooker cue through the mouth

PURPOSE

 This is a unique case report of a self-inflicted orbital injury that presented as a simple upper vestibulum laceration. A 43-year-old man presented to the Oral and Maxillofacial Surgery Unit with a small laceration in his mouth and complaints of pain in his left eye due to a snooker cue penetration. Upon admission, clinical findings included a small laceration on the upper left vestibulum and a subdermal hematoma in the left eye lid with restricted movements of the left eye. Further examination revealed remote trauma to the orbit, penetrating through the oral cavity, passing the maxillary sinus, and the orbital floor causing traumatic optic neuropathy with partial visual loss. The patient was treated conservatively with antibiotics and corticosteroids and a 6-week follow up.

CONCLUSION

 In cases of remote penetrating injury, meticulous examination revealing precise injury mechanism is crucial. All cases of Dento-maxillofacial trauma should include a high degree of clinical suspicion for ocular injury, requiring early diagnosis and treatment to reduce risk of visual loss.

Update on orbital reconstruction

PURPOSE OF REVIEW

Orbital trauma is common and frequently complicated by ocular injuries. The recent literature on orbital fracture is analyzed with emphasis on epidemiological data assessment, surgical timing, method of approach and reconstruction materials.

RECENT FINDINGS

Computed tomographic (CT) scan has become a routine evaluation tool for orbital trauma, and mobile CT can be applied intraoperatively if necessary. Concomitant serious ocular injury should be carefully evaluated preoperatively. Patients presenting with nonresolving oculocardiac reflex, 'white-eyed' blowout fracture, or diplopia with a positive forced duction test and CT evidence of orbital tissue entrapment require early surgical repair. Otherwise, enophthalmos can be corrected by late surgery with a similar outcome to early surgery. The use of an endoscope-assisted approach for orbital reconstruction continues to grow, offering an alternative method. Advances in alloplastic materials have improved surgical outcome and shortened operating time.

SUMMARY

In this review of modern orbital reconstruction, several controversial issues such as surgical indication, surgical timing, method of approach and choice of reconstruction material are discussed. Preoperative fine-cut CT image and thorough ophthalmologic examination are key elements to determine surgical indications. The choice of surgical approach and reconstruction materials much depends on the surgeon's experience and the reconstruction area. Prefabricated alloplastic implants together with image software and stereolithographic models are significant advances that help to more accurately reconstruct the traumatized orbit. The recent evolution of orbit reconstruction improves functional and aesthetic results and minimizes surgical complications.

Treatment with individual orbital wall implants in humans - 1-Year ophthalmologic evaluation

BACKGROUND

In 2009 a method of creating individual, patient specific orbital wall implants using rapid prototyping (RP) was shown in a preliminary human study. That study showed that it is financially viable to produce anatomical models and that this technology could be used in the repair of orbital floor fractures.

MATERIALS AND METHODS

In this study, 24 consecutive subjects who had sustained orbital fractures (14 males, 6 females) without any coexisting central nervous system or globe injury were assessed post-operatively. The first series of 12 patients, recruited during the period 2005-2006, were treated with classical method (CM) of forming titanium mesh by manual manipulation, based on individual subjective assessment of the extent and shape of damaged orbital walls. The following 12 cases, recruited between 2007 and 2008, were treated with patient specific titanium mesh implants designed with an RP method. Early (2 weeks) and late (12 months) follow-up was performed. Patients were evaluated by binocular single vision (BSV) test and an assessment of eye globe motility.

RESULTS

The superiority of the RP treatment method over CM was shown on the basis of early results when BSV loss area and reduction of vertical visual disparity (VVD) in upgaze were considered. Better outcomes for the RP group were confirmed in the late follow-up results which showed a reduction of BSV loss area, correction of primary globe position and a very significant improvement in upgaze.

CONCLUSIONS

One-year post-operatively, functional assessment of pre-bent individual implants of the orbital wall has shown the technique to be a predictable reconstruction method. Nevertheless longer follow-up and an increase in the number of cases treated are required for the full evaluation of the technique.

Orbital trauma, bradycardia, and vomiting: trapdoor fracture and the oculocardiac reflex: a case report

The presentation of vomiting and bradycardia after closed head trauma should invariably prompt concern for significant intracranial injury, yet other less common causes for the clinical picture do exist. This case reports one such scenario in which fracture to the patient's inferior orbital wall resulted in the rare though potentially life-threatening oculocardiac reflex, a vagally mediated phenomenon with possible respiratory, cardiovascular, and gastric motility effects.

MOC-PSSM CME article: Zygomatic fractures

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Understand the common signs, symptoms, and treatment options for zygomatic fractures. 2. Answer basic questions on therapy for zygomatic fractures.

SUMMARY

This maintenance of certification article on zygomatic fractures attempts to review the current approaches to the treatment of these fractures. Although the article does not deal with extended approaches to treatment, it does in a general sense present the preoperative, intraoperative, and postoperative thinking for the plastic surgeon approaching these patients in general practice. A further in-depth review can be obtained through the references at the end of the article.

Late Reconstruction of the Complex Orbital Fractures With Computer-Aided Design and Computer-Aided Manufacturing Technique

BACKGROUND

To construct three-dimensional (3D) imaging and computer generated models of complex orbital fractures, and develop a Computer-Aided Design/Computer-Aided Manufacture (CAD/CAM) system to help improve the surgical planning of complex orbital fracture and promote its outcome.

METHODS

A prospective study was carried out on 17 patients with unilateral complex orbital fractures from Mar 2003 to Mar 2006 at the Shanghai ninth people's hospital. The utilization of a CAD/CAM technique based on Helical computer tomography data, with stereolithographical (SLA) modelling as intermediate step, enabled surgeons to plan for the surgical progress of osteotomy, movement, reposition, fixation and material implanting. Orbital volume was calculated pre and post-operatively. Orbital fracture reconstruction and globe repositioning was performed and followed up 3-9 months post-treatment. Ocular function and aesthetic deformities such as enophthalmos, diplopia and extraocular motility problems were accessed. The data was processed with SAS 6.17 statistical software.

RESULTS

17 patients with complex orbital fractures underwent successful orbital fracture reconstruction surgery. The deformities of orbit, medial canthus, nose, zygomata, maxillary and frontal bone were well corrected. The volume of reconstructed orbit was approximately symmetrical with respect to the contralateral orbit. Enophthalmos was corrected and diplopia, extraocular movement were improved.

CONCLUSIONS

CAD/CAM system enables the surgeon to predict reconstructive surgical steps before the operation, and can help to improve the outcome of surgery. This technique may be proved as one of the most useful clinical tools for orbital surgery.

Anatomical 3-dimensional Pre-bent Titanium Implant for Orbital Floor Fractures

PURPOSE

This cadaver study evaluates the use of pre-bent 3-dimensional titanium mesh implants for orbital floor and medial wall reconstruction.

DESIGN

Nonrandomized comparative study.

PARTICIPANTS

Eight human cadaveric heads (n = 16 orbits).

METHODS

Transcutaneous incisions were used to expose both orbital floors in each cadaveric head. Unilateral orbital floor and medial wall fractures were generated in each specimen. The contralateral orbit remained uninjured. The fractures then were repaired with pre-bent titanium mesh fan plates molded from aluminum templates presenting different sizes. The templates were generated from topographical computed tomography (CT) data previously obtained from normal subjects. The accuracy of orbital reconstruction was evaluated with postoperative CT scans.

MAIN OUTCOME MEASURES

The mean value of the distances between the implant and the bony orbit was evaluated.

RESULTS

The mean distance between all 16 plates and their respective orbital floors/medial walls was 0.81+/-0.74 mm. Mean values were 0.68+/-0.63 mm for the unfractured side and 0.93+/-0.82 mm for the fractured side. No significant differences were found between orbits when evaluated for side of injury, gender, or size of defect.

CONCLUSION

Pre-bent 3-dimensional titanium mesh implants provide accurate reconstruction of orbital floor and medial orbital wall fractures. The mean implant error was <1 mm for all orbits studied.