Accuracy of free-hand positioned patient specific implants (PSI) in primary reconstruction after inferior and/or medial orbital wall fractures

Efficacy of Nasal Septal Complex in the Endoscopic Reconstruction of Medial Orbital Wall

The aim of this study is to investigate the efficacy of nasal septal complex reconstructing the medial orbital wall under some specific circumstances. The authors performed a study that included 10 patients who underwent isolated medial orbital wall fracture (blow-out fracture). All the reconstruction surgery of the patient included in this study fixed defect of medial orbital wall using autologous nasal septal complex (composed of nasal septal cartilage and perpendicular plate of ethmoid). The authors observed postoperative improvements of diplopia or ocular motility disorders of the affected orbit. The surgeries had gained satisfactory results, and without severe postoperative complications. After long-term follow-up, postoperative CT indicated the implant-covered defect of medial orbital wall, and there's no incarceration of the medial rectus. Meanwhile, the authors found there is no crack in the implant, and the surgery using nasal septal complex achieved premorbid orbital form. Autologous nasal septal complex provides a better complement to endoscopic reconstruction of medial orbital wall; this strategy allows nasal septum to reconstruct isolated medial orbital wall defects of various degrees, such as nasal septum fracture and dysplasia of perpendicular plate of ethmoid.

Orbital Floor Fractures: Treatment and Diagnostics - A Survey Among Swiss, German and Austrian Maxillofacial Units

Study Design

N/A.

Objective

This study investigated the different ways of orbital floor reconstruction with special focus on reconstruction materials, imaging modalities (intra-/ post-operative), 3D printing and navigation.

Methods

The heads of all governmental-run or associated cranio-maxillofacial surgery units in Switzerland, Austria and Germany were asked in person or received an email link for an online survey with 12 questions.

Results

The return rate was 57%. The most often selected number of reconstructions was between 10 and 50 per year. Resorbable polydioxanone (PDS) foils (41%) and titanium mesh (18 %) were most often used to reconstruct the orbital floor. 31% use 3D Navigation intraoperative. Post-operative imaging was most often performed with CBCT (34.5%) in patients without complications, whereas CT scans were most often performed (63.3%) in patients with persisting complications. In total, 27% stated that they never use preformed orbital plates, and the remaining units use them more or less regularly. 48% have access to a 3D printer and 75% of the respondents use patient specific implants.

Conclusions

The majority of the participating units prefer to use resorbable material for the reconstruction of the orbital floor defects. 3D printing facilities are not available in the majority of units, but it can be expected that the number of units with 3D printing facilities will rise in the near future.

Comparison of patient specific implant reconstruction vs conventional titanium mesh reconstruction of orbital fractures using a novel method

To compare the reconstruction of orbital fractures using patient-specific implants (PSI) and conventional pre-formed titanium mesh; to develop a method of three-dimensional (3D) superimposition and analysis of the reconstructed orbits; and to present the pitfalls in 3D planning of orbital PSI and how to avoid them. This was a retrospective study of patients with orbital fractures who were treated in our institution between the years 2022 and 2023 using PSI or conservative prefabricated titanium mesh. Three different methods for virtual reconstruction of orbital fractures were used and are detailed with advantages, disadvantages and indications. Data acquired included age, gender, method of reconstruction, functional outcomes and aesthetic outcomes. 3D analysis for accuracy of reconstruction was performed. A total of 23 patients were included; 12 were treated using PSI and 11 using prefabricated titanium meshes. There were 8 male and 4 female patients in the PSI group comparted to 5 and 6 in the prefabricated group. All three virtual methods for reconstruction were used successfully, each with the proper indications. When comparing PSI reconstruction to conventional mesh, a significant difference in accuracy was observed; PSI cases showed an inaccuracy of 0.58 mm compared to 1.54 mm with the conventional method. Complications are presented, and tips for avoiding them are detailed. Three different methods for virtual reconstruction were used successfully; automated computerized reconstruction is used for small defects, repositioning is the superior method for non-comminuted cases while mirroring is the method of choice in comminuted fractures. 3D analysis can be performed using a novel method detailed in this report. PSI reconstruction showed superior results, indicating it should be the method of choice when possible. Pitfalls are presented and approaches to prevent them are discussed. Orbital reconstruction is a very important entity in maxillofacial surgery with crucial functional and esthetical implications, and one should use virtual planning and PSI implants, as they significantly improve outcomes.

Comparison of Anatomical Preformed Titanium Implants and Patient-Specific CAD/CAM Implants in the Primary Reconstruction of Isolated Orbital Fractures-A Retrospective Study

BACKGROUND/AIM

Reconstruction of the fractured orbit remains a challenge. The aim of this study was to compare anatomical preformed titanium orbital implants with patient-specific CAD/CAM implants for precision and intraoperative applicability.

MATERIAL AND METHODS

A total of 75 orbital reconstructions from 2012 to 2022 were retrospectively assessed for their precision of implant position and intra- and postoperative revision rates. For this purpose, the implant position after digital orbital reconstruction was checked for deviations by mirroring the healthy orbit at 5 defined points, and the medical records of the patients were checked for revisions.

RESULTS

The evaluation of the 45 anatomical preformed orbital implant cases showed significantly higher deviations and an implant inaccuracy of 66.6% than the 30 CAD/CAM cases with only 10% inaccuracy. In particular, the CAD/CAM implants were significantly more precise in medial and posterior positioning. In addition, the intraoperative revision rates of 26.6% vs. 11% after 3D intraoperative imaging and the postoperative revision rates of 13% vs. 0 for the anatomical preformed implants were significantly higher than for patient-specific implants.

CONCLUSION

We conclude that patient-specific CAD/CAM orbital implants are highly suitable for primary orbital reconstruction. These seem to be preferable to anatomical preformed implants in terms of precision and revision rates.

Is the Pre-Shaping of an Orbital Implant on a Patient-Specific 3D-Printed Model Advantageous Compared to Conventional Free-Hand Shaping? A Systematic Review and Meta-Analysis

This study aimed to perform a systematic review and meta-analysis to compare pre-shaped implants on a patient-specific 3D-printed (3DP) model to manual free-hand shaping (MFS) for orbital wall reconstruction. The PRISMA protocol was followed in this study, and the review was registered in the PROSPERO database (CRD42021261594). A search was conducted in MEDLINE (PubMed), Embase, Cochrane Library, Clinicaltrials.gov, Google Scholar, and the grey literature. Ten articles were included, and six outcomes were analyzed. In total, 281 patients were in the 3DP group and 283 were in the MFS group. The studies had an overall high risk of bias. 3DP models resulted in a better accuracy of fit, anatomical angle reproduction, and defect area coverage. The correction of orbital volume was also superior with statistical significance. There was a higher percentage of the correction of enophthalmos and diplopia in the 3DP group. Intraoperative bleeding and hospital stay were reduced in the 3DP group. The meta-analysis of operative time showed a reduction in the average operative time by 23.58 min (95% CI: -43.98 to -3.19), which was statistically significant (t(6) = -2.8299, p = 0.0300). The 3DP models appear advantageous for an accurate orbital wall reconstruction, with fewer complications than those for conventional free-hand-shaped implants.