Surgical treatment of enophthalmos using an endoscope and T-shaped porous polyethylene fabricated with a mirror image

Comparison of Postoperative Enophthalmos Between Fresh and Delayed Unilateral Orbital Fractures After Orbital Reconstruction With Titanium Mesh Using Computer-Assisted Navigation

This study compares postoperative enophthalmos between fresh and delayed unilateral orbital fractures after orbital reconstruction with titanium mesh using computer-assisted navigation. The sample was composed of 45 patients with post-traumatic unilateral enophthalmos who were divided into the fresh fracture group and the delayed fracture group. They underwent orbital reconstruction with standard preformed orbital implants and computer-assisted navigation system. The following parameters were measured with computed tomography images: the degree of enophthalmos, orbital volume, and fracture defect area. Patients were reviewed preoperatively (T0), 1 week postoperatively (T1), and 6 months postoperatively (T2). Computed tomography measurements showed that in both groups, the degree of enophthalmos decreased after surgery but increased significantly from T1 to T2 ( P <0.05). ΔE (difference in the degree of enophthalmos between T1 and T2) was similar in patients with fresh and delayed fractures. There was a significant difference in the degree of ΔE between patients with single-wall orbital fractures and those with two-wall orbital fractures. The findings indicate that postoperative enophthalmos is common in both the groups and is closely related to the degree of preoperative enophthalmos. Furthermore, the recurrence of enophthalmos is similar between the 2 groups, but it is higher in patients with orbital fractures involving 2 walls.

Aging of the Adult Bony Orbit

BACKGROUND

Accurate quantitative data of the adult bony orbital volume and dimension are needed for treatment optimization. In the present study, the authors aim to evaluate adult orbital volume and corresponding linear dimensions according to age, volume, and individual symmetry.

METHODS

Seventy computerized tomography facial scans of adults were randomly chosen from an institutional database and 3-dimensionally reconstructed. Studies were excluded for orbital pathology or incomplete radiographic data. Anatomic landmarks were marked. Interval linear distances and orbital volumes were calculated. Data were analyzed using paired T-tests, independent T-tests, linear regression analysis, and 1-way analysis of variance.

RESULTS

A total of 140 orbits from 70 patients were analyzed (female = 35, male = 35), ranging from 20 to 88 years of age. Orbital volume was similar between an individual's left and right side; however, a difference was observed in vertical orbital height, orbital width, inferior orbital rim position, orbital roof length, orbital width, and medial orbital wall length (0.45, 0.64, 0.4, 0.77, 0.97, and 5.1 mm, respectively; P < 0.05). In comparison to females, males averaged larger orbital volume by 3.07 cm (29.58 cm versus 26.51 cm, P = 0.0002), medial wall length by 2.66 mm (P < 0.05), and orbital width by 2.66 mm (P < 0.05). Orbital volume did not correlate with patient age, while lateral wall length was correlative.

CONCLUSION

This accurate normative data of the adult bony orbit impacts key aspects of patient diagnosis and treatment and also suggest clinical signs of periorbital aging are not due to bony orbital changes.

Porous Polyethylene Coated with Functionalized Hydroxyapatite Particles as a Bone Reconstruction Material

In this study, porous polyethylene scaffolds were examined as bone substitutes in vitro and in vivo in critical-sized calvarial bone defects in transgenic Sprague-Dawley rats. A microscopic examination revealed that the pores appeared to be interconnected across the material, making them suitable for cell growth. The creep recovery behavior of porous polyethylene at different loads indicated that the creep strain had two main portions. In both portions, strain increased with increased applied load and temperature. In terms of the thermographic behavior of the material, remarkable changes in melting temperature and heat fusion were revealed with increased the heating rates. The tensile strength results showed that the material was sensitive to the strain rate and that there was adequate mechanical strength to support cell growth. The in vitro cell culture results showed that human bone marrow mesenchymal stem cells attached to the porous polyethylene scaffold. Calcium sulfate–hydroxyapatite (CS–HA) coating of the scaffold not only improved attachment but also increased the proliferation of human bone marrow mesenchymal stem cells. In vivo, histological analysis showed that the study groups had active bone remodeling at the border of the defect. Bone regeneration at the border was also evident, which confirmed that the polyethylene acted as an osteoconductive bone graft. Furthermore, bone formation inside the pores of the coated polyethylene was also noted, which would enhance the process of osteointegration.

[Posttraumatic enophthalmos correction by bone graft: Why the unpredictable results?]

PURPOSE OF THE STUDY

Posttraumatic enophthalmos cause complex cosmetic problems to fix. In order to get better results, we wanted to calculate the volume of parietal bone graft needed to be put in place, know where to place it in orbit and study soft tissues' participation.

PATIENTS AND METHOD

In a retrospective study, we have calculated on scanner the volume of bone and soft tissue as well as the volume and the location of the graft. We have compared, between two groups ("good result" and "insufficient result"), graft volumes, taking into account differences in bone's volume between the healthy and the traumatized orbit. A comparison of the locations of the graft was also made. We were trying to find out if these factors were involved in the quality of the result.

RESULTS

Twenty-nine surgeries on 24 patients were analyzed. The average bone's volume of an orbit with enophthalmos was 24.76 cm(3) for 17.12 cm(3) of soft tissue. Retro-lens distance was the most reliable measurement method of enophthalmos (P=0.001). There was a trend to a more substantial over-correction in the group "good result". A significant increase (P=0.0008) of soft tissue volumes in the traumatized orbit was found.

CONCLUSION

This last result is surprising. Many authors believe that there is a scar retraction of soft tissues. But Kronish et al. showed an increase of the fat density and connective tissue. This, together with the assumption of a weathering of the ligament suspension of the globe, may affect our aesthetic results. MRI, ultrasound and anatomopathological studies would allow a better understanding of the fat, muscle and ligament pathophysiologies of an orbit with enophthalmos.