Use of membrane and bone grafts in the reconstruction of orbital fractures

Discovery of CTSK+ Periosteal Stem Cells Mediating Bone Repair in Orbital Reconstruction

Purpose

The purpose of this study was to explore the role of cathepsin K positive (CTSK+) periosteal stem cells (PSCs) in orbital bone repair and to clarify the source of endogenous stem cells for orbital bone self-repair.

Methods

Periosteum samples obtained by clinical orbital bone repair surgery were analyzed, after which immunofluorescence and immunohistochemical staining were used to detect the content of bone marrow-derived cells and CTSK+ PSCs in periosteum as well as the mobilization of PSCs. CTSK+ PSCs were characterized by flow cytometry. Transcriptome sequencing was used to compare the transcriptomic characteristics of CTSK+ PSCs and bone marrow mesenchymal stem cells (BMSCs).

Results

The orbital periosteum contained CTSK+CD200+ cell lineage, including CD200+CD105- PSCs and CD200+CD105+ progenitor cells. CTSK and osteocalcin (OCN) colocalized in the inner layer of the orbital periosteum, suggesting the osteogenic differentiation potential of CTSK+ PSCs. CTSK expression was much higher in periosteum after mobilization. Immunofluorescence showed low amounts of scattered CD31+ and CD45+ cells in the orbital periosteum. The stem cell characteristics of CTSK+ PSCs were verified by multidirectional differentiation. Flow cytometry found CD200+CD105- CTSK+ PSCs and CD200variantCD105+ progenitor cells. Transcriptome sequencing of CTSK+ PSCs and BMSCs found 3613 differential genes with significant differences. Gene Ontology (GO) analysis showed the differences between the two types of stem cells, revealing that PSCs were more suitable for intramembranous osteogenesis.

Conclusions

CTSK+ PSCs may be endogenous stem cells for orbital bone repair. They are mobilized after orbital fracture and have unique features suitable for intramembranous osteogenesis, completely different from BMSCs.

Diagnosis and surgical treatment of defects in the wall of the orbit of children and adults using demineralized bone allografts

Accuracy of diagnosis defines the quality of treatment in patients with traumatic damage to eyelet walls. In this area, complex functional and anatomical breaches are typical and require full characterization of pathological changes in bone and soft tissue structures. A new plastic material with a high degree level of demineralization called "Perfoost" can be used to treat defects in the bones of the face of children and adults. In the present study, 79 patients with fractured eyelet walls were treated between 1999 and 2006 by grafting the defect wall with demineralized bone allografts. Grafts were applied from 2 days to 18 months after trauma. Magnetic resonance computer CT was used to check the realignment of allografts every 6 months after the reconstructive operation. The post-operative period of the observation was from 6 months to 7 years after the operation. Good or satisfactory results were obtained for 97.47 % of patients.

Controversies in orbital reconstruction--I. Defect-driven orbital reconstruction: a systematic review

In the 1980s, computed tomography was introduced as an imaging modality for diagnosing orbital fractures. Since then, new light has been shed on the field of orbital fracture management. Currently, most surgeons are likely to repair orbital fractures based on clinical findings and particularly on data obtained from computed tomography scans. However, an important but unresolved issue is the fracture size, which dictates the extent and type of reconstruction. In other fields of trauma surgery, an increasing body of evidence is stressing the importance of complexity-based treatment models. The aim of this study was to systematically review all articles on orbital reconstruction, with a focus on the indication for surgery and the defect size and location, in order to identify the reconstruction methods that show the best results for the different types of orbital fractures.

A review of materials currently used in orbital floor reconstruction

Orbital fractures are common fractures of the midface. As such, numerous techniques and materials exist for the repair of this region, each with inherent advantages and disadvantages. But does the ideal implant material exist? Should we stop and simply use readily available materials, or should the cycle of need and discovery continue? A comprehensive review of materials used in orbital reconstruction and possible new directions in orbital floor reconstruction are presented.

Customized orbital floor soft tissue retractor

For the correction of blow out fractures of the orbit, the retraction of orbital floor contents are necessary. We are here in presenting a customized orbital floor soft tissue retractor to overcome the disadvantages of the conventional Rows orbital floor retractor.

Biomaterials and implants for orbital floor repair

Treatment of orbital floor fractures and defects is often a complex issue. Repair of these injuries essentially aims to restore the continuity of the orbital floor and to provide an adequate support to the orbital content. Several materials and implants have been proposed over the years for orbital floor reconstruction, in the hope of achieving the best clinical outcome for the patient. Autografts have been traditionally considered as the "gold standard" choice due to the absence of an adverse immunological response, but they are available in limited amounts and carry the need for extra surgery. In order to overcome the drawbacks related to autografts, researchers' and surgeons' attention has been progressively attracted by alloplastic materials, which can be commercially produced and easily tailored to fit a wide range of specific clinical needs. In this review the advantages and limitations of the various biomaterials proposed and tested for orbital floor repair are critically examined and discussed. Criteria and guidelines for optimal material/implant choice, as well as future research directions, are also presented, in an attempt to understand whether an ideal biomaterial already exists or a truly functional implant will eventually materialise in the next few years.

Orbital floor reconstruction: a retrospective study of 21 cases

OBJECTIVE

The purpose of this retrospective study was to investigate the diagnostic methods, therapeutic principles, surgical approach, and materials used for orbital floor reconstruction.

STUDY DESIGN

This study consisted of 21 cases with orbital fractures treated at the Hospital of Stomatology, Sichuan University, China, between July 2002 and June 2006. Inclusion criteria were patients with fractures of the orbital floor with bone defects. Patients were retrospectively analyzed for gender, age, mechanism of injury, classification of fracture, and complications.

RESULTS

CT scans were 100% accurate in diagnosing the fractures. Shaped autogenous bone, titanium mesh, and Medpor were respectively implanted under the periosteum of the orbital floor in 5 cases, 10 cases, and 6 cases. All the patients had good results including significant improvements in appearance and function after surgery. There were no severe permanent complications. Two cases had postoperative wound infections, and 1 case had temporary blindness that resolved completely.

CONCLUSIONS

CT scan is the first choice of investigation for an orbital floor fractures. The objectives of treatment for an orbital floor fracture with a bony defect are reduction of the prolapsed orbital contents and reconstruction of the orbital floor with repair materials, to restore the normal orbital floor and orbital capacity. A subciliary incision was adopted in our surgery. At present, porous polyethylene and titanium mesh are considered to be the ideal orbital floor repair materials. Titanium mesh was used in fractures with large defects that were not easy to fix without obvious enophthalmos. Porous polyethylene can be used in fractures when there is a need to restore the orbital volume.

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.

Reconstruction of an orbital floor fracture in a 4-year-old child

The authors present a case of a 4-year-old girl with an orbital floor fracture. During surgery absorbable collagenous mesh (Pelvicol) was placed between the bone wall and the orbital periosteum. Pelvicol was selected as a natural xenogeneic tissue (porcine dermis) ready for first use in the reconstruction of the orbital floor fracture. The patient has fully recovered without any symptoms.

Blow-out fractures in children: six years’ experience

OBJECTIVES

To present and analyze our experience in treating blow-out fractures in children, over a 6-year period.

STUDY DESIGN

The study was retrospective with 16 consecutive cases of blow-out fractures in children aged 5 to 15 years. All patients presented with impairment of eye motility and diplopia together with radiological findings. Treatment included fracture reduction, release of entrapped periorbital soft tissues, and placement of an alloplastic membrane on the orbital floor. Fractures were linear in 11 cases (trapdoor) and severe or comminuted in 5 cases.

RESULTS

Clinical symptoms subsided in all cases. Complete recovery of eye motility was achieved after surgical procedure in 13 cases; 2 patients presented late but had full recovery, and 1 patient, 4 years postoperatively, still had slight motility impairment.

CONCLUSIONS

Surgical treatment of blow-out fractures, including periorbital tissue release and placement of a membrane lining on the orbital floor, presented satisfactory results in our cases.

Reconstruction of Internal Orbital Wall Fracture with Iliac Crest Free Bone Graft: Clinical, Computed Tomography, and Magnetic Resonance Imaging Follow-Up Study

BACKGROUND

The purpose of this study was to clinically and radiologically assess the outcome of internal orbital reconstruction with an iliac bone graft.

METHODS

Twenty-four consecutive patients with unilateral orbital wall fractures were enrolled in this prospective study. A medial cortical wall from the anterior ilium was used for reconstruction. At each follow-up visit, globe posture, diplopia, and eye movements were assessed. Coronal and sagittal computed tomography and magnetic resonance imaging were used to observe graft posture, bone defects, and intraorbital soft-tissue changes.

RESULTS

Most fractures (46 percent) were pure orbital floor fractures. The mean follow-up was 7.8 months. One patient with medial wall and floor fractures required reoperation because of insufficient bone graft. At the last follow-up, this was the only patient (4 percent) with both enophthalmos (2 mm) and hypophthalmos (3 mm). Five patients (21 percent) had hypophthalmos (> 1 mm) at the end of the study. Resorption and remodeling were detected in all grafts, but no grafts were totally resorbed. Sagittal or coronal bone graft postures were assessed as good in 18 orbits (75 percent). Bone defects (> 10 mm) at reconstructed areas were detected in 13 orbits (54 percent). Scar tissue was observed only in three reconstructed orbits (13 percent). Diplopia in central field of vision was registered in seven patients preoperatively but in none at the end of the study.

CONCLUSIONS

The resorption rate was high, but most of it was advantageous remodeling. Overall outcome was good. Secondary operations led to poor outcomes. Thin computed tomography and magnetic resonance imaging sections (< or = 2 mm) are needed to evaluate accurately bone graft placement and posture and orbital volume.

[Secondary midfacial reconstruction using different surgical techniques and computer assisted surgery]

AIM

Aim of this retrospective study was to assess the outcome after secondary midfacial reconstruction using different operation techniques and computer assisted surgery. Functional and aesthetic aspects as well as experiences are reported.

PATIENTS AND METHODS

18 patients were assessed for enophthalmos, diplopia, and aesthetics during a follow-up period of up to 2.5 years.

RESULTS

In 40% of the patients several techniques for soft and hard tissue reconstruction were used. In 5 of the 9 patients diplopia was improved; in 4 patients there was no change. A significant enophthalmos was corrected in 8 out of 12 patients. After additional surgery 6 patients had a good aesthetic result, 7 a satisfactory and 5 a poor.

CONCLUSION

For secondary midfacial reconstruction often a combination of different surgical techniques is necessary. Bony asymmetries and enophthalmos were successfully corrected, however, functional and aesthetic impairment due to bad soft tissue condition are difficult to correct. Computer assisted surgery is helpful for dissection within the orbit, for graft placement, and for positioning of osteotomized segments.

Efficacy of computer-assisted surgery in secondary orbital reconstruction

PURPOSE

In this study the efficacy of computer-assisted surgery (CAS) used for secondary orbital reconstruction after midfacial fractures was evaluated, comparing the clinical outcome with that after conventional surgery (CS). Special consideration was given to whether CAS can reduce the number of secondary corrections.

PATIENTS AND METHODS

Twenty consecutive patients (24 orbits; 12 in each group) were assessed for enophthalmos, diplopia, and aesthetics during a follow-up period of up to 3 years.

RESULTS

After CAS, enophthalmos was fully corrected in 8 of 11 orbits but after CS in only 6 of 10 orbits. Improvement of diplopia was achieved in 1 of 7 (CAS) and in 3 of 4 (CS) patients. The aesthetic result after secondary reconstruction and additional surgery was better in the CAS group. Additional surgery to correct bony structures was only necessary in 3 patients of the CS group. Additional soft tissue surgery was necessary in both groups.

CONCLUSION

CAS can improve the clinical outcome of reconstructive bone surgery reducing the amount of additional hard tissue procedures. It was helpful during dissection of the scarred orbital tissue and placement of a graft. However, it had no impact on soft tissue correction especially with respect to function.

Repair of Traumatic Orbital Wall Defects Using Conchal Cartilage

BACKGROUND

The authors' aim was to investigate the efficiency of conchal cartilage grafts in defective orbital wall fractures, which are encountered isolated or in combination with other orbitozygomatic fractures. The authors assessed, for this purpose, the follow-up results of patients treated by using conchal cartilage grafts.

METHODS

Ten patients who had defective orbital wall fractures and were treated by using conchal cartilage graft among those treated for facial fractures in the authors' clinic were included in the study. The wall defects in the patients were detected either with preoperative radiologic images or with orbital exploration performed to look for a possible defect accompanying the fracture with orbital extension during the operation. In all patients (four isolated and six combined orbital fractures), who had defects varying from 100 to 400 mm, conchal cartilage grafts were adapted to the defect. In the postoperative follow-up, Hertel exophthalmometry was also performed together with clinical examination so that enophthalmos that might develop as a complication could be assessed.

RESULTS

In the postoperative period, cartilage graft was palpated slightly in two patients at the edge of the infraorbital rim. Limitation in eye movement, diplopia, and enophthalmos did not occur in our patients, except for one who reported to us 1 year after the primary trauma. No complication in the donor area was observed.

CONCLUSIONS

Conchal cartilage could be considered one of the autogenous materials among those materials suitable for the repair of defective orbital wall fractures that are not oversized. It has the advantages of being adequate for reconstruction of the fracture, easy to obtain, easily adaptable to the orbital walls, and having minimum morbidity at the donor site.