Long-term result of a biodegradable osteo-inductive copolymer for the treatment of orbital blowout fracture

[Potential of bony regrowth after deep lateral orbital decompression]

The article describes a very rare case of bony regrowth after deep lateral orbital decompression for thyroid eye disease. Bony regrowth was observed in the area of the resected «trigone» of the greater wing of the sphenoid bone and in the area of the exposed dura mater. This case demonstrates that bony regrowth can be a possible cause of exophthalmos (proptosis) recurrence after orbital decompression in thyroid eye disease without clinical or laboratory evidence of reactivation of the disease.

Resorbable Implants for Orbital Fractures: A Systematic Review

BACKGROUND

Orbital fractures are one of the most common sequelae of facial trauma.

OBJECTIVE

The objective of this study was to summarize published data for resorbable implants in orbital reconstruction, including polymer composition, degradation characteristics, osteoconductivity, and complications such as enophthalmos, diplopia, and peri-implant inflammation. A literature search of the National Library of Medicine was performed via PubMed using the keyword resorbable orbital implant. A total of 27 studies were reviewed. Strength of data was assessed according to the Oxford Centre criteria.

RESULTS

Most commercially available implants provide adequate tensile strength for up to 6 months (with the exception of polydioxanone, which loses strength within 1 month, and poly(D,L-lactide) within 3 months). This is sufficient for the isolated orbital floor or medial wall (tensile strength, ~300 MPa) but insufficient for reconstruction of load-bearing areas (eg, the inferior orbital rim with tensile strength of ~1.2 GPa). Thicker products (>1 mm) have increased risk for delayed inflammation than thinner products. Postoperative complications including delayed inflammation (0%-9%), eyelid malposition (0%-5%), enophthalmos (5%-16%), diplopia (0%-16%), infection (0%-2%), and infraorbital nerve hypesthesia (2%-18%) are variably distributed across implants with several notable exceptions: poly(L-lactide) has an increased risk of delayed inflammation, and polydioxanone has a risk of delayed enophthalmos and hematoma.

CONCLUSIONS

Resorbable implants are suitable for isolated medial wall or floor fractures with intact bony buttresses and function as a barrier rather than a load-bearing support.

Reconstruction of Medial Wall Blowout Fracture Defect with a Combination of Resorbable Meshed Plate and Cancellous Bone Allograft

Background

Various materials are available for the reconstruction of bone defects in cases of medial wall blowout fracture. This study was conducted to assess the efficacy of the combination of a resorbable meshed plate and cancellous bone allograft.

Methods

From March 2014 to March 2017, a total of 111 patients were evaluated. Sixty-three patients received reconstruction surgery with porous polyethylene plates (control group) and the other forty-eight patients underwent operation with a resorbable meshed plate plus allogenic cancellous bone (combined group). The results were assessed by exophthalmometric measurements, width, and volume discrepancies as compared with the unaffected orbit, and operation time.

Results

The difference in exophthalmometric measurements between the affected and unaffected orbits were 0.94 ± 0.70 mm in the control group and 1.05 ± 0.73 mm in the combined group without statistical significance (p = 0.425). In the analysis of computed tomography images, the width discrepancy was 1.55 ± 0.86 mm and 1.08 ± 0.69 mm, respectively (p = 0.003); however, the volume discrepancy demonstrated no statistically significant difference (2.58 ± 1.40 cm³ versus 2.20 ± 1.80 cm³; p = 0.209). Operation time was significantly shorter in the combined group as compared with the control group (43.0 ± 7.0 versus 38.3 ± 7.0 minutes; p = 0.001).

Conclusion

The combination material composed of resorbable meshed plate and cancellous bone allograft made reconstruction surgery of medial wall blowout fracture easier and quicker to perform with long-lasting results.

Bony Regrowth After Deep Lateral Orbital Decompression

PURPOSE

To report on 2 cases of late bony regrowth with clinically apparent proptosis after deep lateral orbital decompression for thyroid orbitopathy.

METHODS

A retrospective review of 2 cases identified by the authors as having late bony regrowth. The authors review the clinical, historical, radiologic, and anatomical findings and discuss the significance thereof.

RESULTS

Bony regrowth with bowing toward the middle cranial fossa is observed at postoperative month 8 in the first case. Cortical bone and marrow was observed to regrow at 2 years postoperatively in the second case. Both patients underwent successful repeat deep lateral orbital decompression with resolution of proptosis and clinical symptoms.

CONCLUSIONS

Late bony regrowth should be considered as a possible cause of recurrent proptosis after orbital decompression in thyroid eye disease.

Application of Computer-Aided Designing and Rapid Prototyping Technologies in Reconstruction of Blowout Fractures of the Orbital Floor

INTRODUCTION

Traumatology of the maxillofacial region represents a wide range of different types of facial skeletal injuries and encompasses numerous treatment methods. Application of computer-aided design (CAD) in combination with rapid prototyping (RP) technologies and three-dimensional computed tomography techniques facilitates surgical therapy planning for efficient treatment.

OBJECTIVE

The purpose of this study is to determine the efficiency of individually designed implants of poly-DL-lactide (PDLLA) in the reconstruction of blowout fractures of the orbital floor.

METHODS

In the course of a surgical treatment, individually designed implants manufactured by CAD/RP technologies were used. Preoperative analysis and postoperative monitoring were conducted to evaluate the successfulness of orbital floor reconstruction using customized PDLLA implants, based on: presence of diplopia, paresthesia of infraorbital nerve, and presence of enophthalmos.

RESULTS

In 6 of the 10 patients, diplopia completely disappeared immediately after surgical procedure. Diplopia gradually disappeared after 1 month in 3 patients, whereas in 1, it remained even after 6 months. In 7 patients, paresthesia disappeared within a month after surgery and in 3 patients within 2 months. Postoperative average Orbital volume (OV) of the injured side (13.333 ± 3.177) was significantly reduced in comparison with preoperative OV (15.847 ± 3.361) after reconstruction of the orbital floor with customized PDLLA implant (P < 0.001). Thus, average OV of corrected orbit was not different compared with the OV of the uninjured orbit (P = 0.981).

CONCLUSIONS

Reconstruction of blowout fractures of the orbital floor by an individually designed PDLLA implant combined with virtual preoperative modeling allows easier preoperative preparation and yields satisfactory functional and esthetic outcomes.

The use of anatomically drop-shaped bioactive glass S53P4 implants in the reconstruction of orbital floor fractures--A prospective long-term follow-up study

An isolated fracture of the orbital floor needs reconstruction if there is a clear herniation of adipose tissue or of the rectus inferior muscle into the maxillary sinus. A prospective study was carried out treating 20 patients with an isolated blow-out fracture of the orbital floor or with a combined zygomatico-orbito-maxillary complex fracture, using a newly designed anatomically drop-shaped implants made of bioactive glass (BAG) S53P4. Computed tomography (CT) was performed immediately postoperatively to confirm the correct position of the plate. The patients were followed up for an average of 32 months clinically and radiologically with magnetic resonance imaging (MRI) for an average of 31 months. None of the patients had any signs of complications related to the implant and the clinical outcome was very good. None of the patients had persisting diplopia. The level of the pupillas was normal in 15 of 20 patients. Minor hypo-ophthalmos ranging from 0.5 to 1.0 mm was observed in three patients, and moderate hypo-ophthalmos of 2.0 mm was seen in one patient. Hyperophthalmos of 1.0 mm was seen in one patient. Minor enophthalmos on the operated side ranging from 0.5 to 1.0 mm was seen in eight patients. Mild to moderate paraesthesia of the infraorbital nerve was observed in six patients. The immediate postoperative CT and the long term follow-up MRI revealed that the drop-shaped BAG implants retained their correct position in the orbital floor and did not show any evidence of losing their original shape or material resorption. No adverse tissue reaction was associated with the material. Due to the anatomical drop shape, the implants could successfully maintain the orbital volume and compensate for the retrobulbar adipose tissue atrophy.

Reconstruction of orbital floor blow-out fractures with autogenous iliac crest bone: a retrospective study including maxillofacial and ophthalmology perspectives

This is a 10-year retrospective study of patients with an isolated unilateral orbital floor fracture reconstructed with an autogenous iliac crest bone graft. The following inclusion criteria applied: isolated orbital floor fracture without involvement of the orbital rim or other craniofacial injuries, pre-/post-operative ophthalmological/orthoptic follow-up, pre-operative CT. Variables recorded were patient age and gender, aetiology of injury, time to surgery, follow-up period, surgical morbidity, diplopia pre- and post-operatively (Hess test), eyelid position, visual acuity, and the presence of en-/or exophthalmos (Hertel exophthalmometer). Twenty patients met the inclusion criteria. The mean age was 29 years. The mean follow up period was 26 months. No patient experienced significant donor site morbidity. There were no episodes of post-operative infection or graft extrusion. Three patients had diplopia in extremes of vision post-operatively, but no interference with activities of daily living. One patient had post-operative enophthalmos. Isolated orbital blow-out fractures may be safely and predictably reconstructed using autogenous iliac crest bone. The rate of complications in the group of patients studied was low. The value of pre- and post-operative ophthalmology consultation cannot be underestimated, and should be considered the standard of care in all patients with orbitozygomatic fractures, in particular those with blow-out fractures.