Do Patient-Specific Implants Decrease Complications and Increase Orbital Volume Reconstruction Accuracy in Primary Orbital Fracture Reconstruction?

Orbital Patient-Specific (Customized) Implants: A Report by the American Academy of Ophthalmology

PURPOSE

To review systematically the literature on the efficacy and safety of the use of patient-specific implants (PSIs) in orbital reconstructive surgery.

METHODS

A literature search was last conducted in January 2025 in the PubMed database for English language original research that assessed the use of any PSI reported for orbital reconstructive surgery. Of the 219 articles identified, 51 met the inclusion criteria for this assessment and were selected for full-text review and data abstraction. A total of 19 studies met the study criteria, and the panel methodologist assigned a level III rating to each study.

RESULTS

No study met the criteria for level I or II evidence. Eight of the 19 studies compared a PSI group with a control group (other forms of implants such as preformed, prebent sheets)-5 studies involved acute fracture repair and 3 involved a mixture of acute, delayed, or revision surgery. The remaining 11 studies did not have a comparison group, and indications included acute fracture repair (n = 2), delayed or secondary fracture repair (n = 3), or an after-tumor resection (n = 5). One study compared outcomes using PSIs designed using automated software with PSIs designed manually. Patient-specific implant material included titanium (n = 12), polyether ether ketone (PEEK) (n = 3), porous polyethylene (n = 2), and ceramic (n = 2). Time to manufacture implants ranged from 1 to 35 days, with most under 10 days. Volumetric analysis generally reported greater improvement in postoperative orbital volume for PSIs compared with non-PSIs. Clinical improvement in diplopia, enophthalmos, and extraocular motility was variably reported and largely not statistically analyzed or significant. Complications were variably reported and included expected complications after orbital fracture repair.

CONCLUSIONS

The existing literature on PSIs for orbital surgery contains a heterogeneity of indications, designs, materials, and reporting. Because all studies met level III criteria for evidence, definitive conclusions were limited. Although anecdotal and low-quality evidence reports showed possible improved outcomes with PSIs compared with non-PSIs, determination of the best applications, designs, outcomes, and safety will require well-designed prospective studies with sufficient postoperative follow-up and outcome metrics.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Orbital Remodeling and 3-dimensional Printing in Delayed Orbital Floor Fracture Reconstructions

The mechanism and physiology of orbital cavity remodeling after orbital fractures is not well described. This poses a challenge in the delayed operative treatment of orbital floor fractures due to variations from expected anatomy and may risk injury to critical structures during exploration as well as misguided reconstruction, causing persistent ocular dystopia. We report a case where significant orbital remodeling caused unexpected challenges to orbital floor reconstruction, highlighting the need for further research in this field. A 23-year-old previously healthy man was treated conservatively for a left orbital floor fracture sustained during a rugby match. At a 4-month follow-up, the patient was found to have significant ocular dystopia with vertical diplopia and cosmetically significant enophthalmos. A discrepancy of 4 mm was noted on exophthalmometry. Intraoperatively, the neo-floor was found to have fully healed but with significant downsloping angulation and clinically appreciable depression. Furthermore, no fracture ledges were able to be used to guide the height of the titanium reconstruction plate, posing a significant challenge. Therefore, a 3-dimensional printed model of the orbit using a recent computed tomography scan was used to conform the plate to the required dimensions. The patient made a good recovery without ocular symptoms. Fracture remodeling of the orbital cavity is poorly described and may not be considered in the delayed treatment of orbital fractures. Further research to describe the mechanism and pattern of how this occurs is necessary. Computer-assisted design with 3-dimensional printing is a useful tool that can help overcome technical challenges in complex maxillofacial cases.

Need for Redo Surgery of Maxillofacial Fractures

The purpose of the present study was to describe the demographic and clinical features of patients having undergone redo surgery for mandibular and/or midfacial fractures and to identify factors that increase the odds of redo surgery. Included were the files of all patients who had undergone open reduction and fixation of one or more mandibular and/or midfacial fracture or orbital reconstructions at the Department of Oral and Maxillofacial Surgery, Helsinki University Hospital, Helsinki, Finland, between 1 January 2013-31 October 2020. Patients having undergone redo surgery were identified, and descriptive characteristics were calculated. In the data analysis, the association between redo surgery and explanatory variables was analyzed. Altogether, 1176 patients were identified for the analysis. Of these, 25 (2.1%) underwent redo surgery for 28 fracture sites. The most common reasons for redo surgery were inadequate fracture reductions of the zygomatic process or the mandible (19 patients) and inadequate orbital reconstructions (four patients). Compared with surgery of only the mandible, combined surgery of the mandible and midface had almost four times greater odds of redo surgery (95% CI 3.8, 0.8-18.4), but the finding was not statistically significant. Although redo surgery was required fairly infrequently, the findings highlight the relevance of surgical competence to treatment success; suboptimal surgical procedure was the most common reason for redo surgery. The literature supports the use of intraoperative CT scanning as a useful tool in association with the treatment of complex midfacial fractures in general and orbital fractures in particular. The success of orbital reconstruction can be promoted by using patient-specific implants.

Long-term enophthalmos after complex orbital bone loss successfully treated with patient-specific porous titanium implants: A case series

INTRODUCTION

Long-term enophthalmos and diplopia resulting from orbital bone loss pose significant challenges in reconstructive surgery. This study evaluated the effectiveness of patient-specific porous titanium implants (PSIs) for addressing these conditions.

MATERIALS AND METHODS

This retrospective study involved 12 patients treated at Croix-Rousse Hospital, Lyon, from April 2015 to April 2022 who underwent late reconstruction via PSI for unilateral complex orbital bone loss. These implants were customized via 3D mirroring techniques on the basis of high-resolution computed tomography (CT) scans of the patients' unaffected orbits.

RESULTS

All 12 patients presented with significant preoperative enophthalmos, with an average displacement of 3.24 mm, which was effectively corrected postoperatively to an average of 0.17 mm (p < 0.001). Orbital volume notably improved from a preoperative average of 3.38 mL to 0.37 mL postsurgery (p < 0.001). Functional improvements were evident as both enophthalmos and diplopia resolved completely. The Lancaster test revealed an improvement in the visual field, with 83.3 % of patients achieving normal results postoperatively.

DISCUSSION

By ensuring anatomical accuracy, patient-specific porous titanium implants, tailored from patient-specific imaging and fabricated via advanced 3D printing technology, provide a precise, effective, and reliable solution for reconstructing complex orbital defects and performing complicated revision surgeries.

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.

Does a Point-of-Care 3-Dimensional Printer Result in a Decreased Length of Surgery for Orbital Fractures?

BACKGROUND

Utilization of point-of-care 3-dimensional printing (3DP) has decreased length of surgery in facial trauma. Little is known regarding 3DP's impact on length of surgery in orbital fracture.

PURPOSE

The purpose of this study was to compare length of surgery between 3DP/preadapted (3DPPA) orbital plates and intraoperative adapted plates (IOAP) for orbital fracture reconstruction.

STUDY DESIGN, SETTING, SAMPLE

This was a prospective, non-blinded, randomized clinical study of consecutive subjects with orbital fractures presented to Grady Memorial Hospital in Atlanta, Georgia, between January 2018 and June 2021. Subjects ≥ 18 years, unilateral fracture, no previous orbital surgery, and/or congenital craniofacial anomaly were included. We excluded subjects <18 years and bilateral fractures.

PREDICTOR/EXPOSURE/INDEPENDENT VARIABLE

Primary predictor variable was the treatment approach. Randomization software was used, and subjects were randomized to 3DPPA or IOAP groups.

MAIN OUTCOME VARIABLE(S)

Primary outcome variable was length of surgery in minutes. Secondary outcomes were the time required for plate insertion and fixation in minutes, operating room (OR) charges, and orbital volume (OV) calculation.

COVARIATES

Age, sex, race, etiology, laterality, location, dimension, indication for surgery, postoperative enophthalmos, and diplopia.

ANALYSES

Univariate and bivariate analyses were calculated. Statistical significance was P < .05.

RESULTS

Twenty-five subjects met the inclusion criteria. Mean ages in 3DPPA and conventional IOAP groups were 41.5 (±9) and 38.2 (±10, P = .31), respectively. The mean length of surgery was 32.6 (±13.7) in 3DPPA and 53.3 (±12.8, P < .001) in conventional IOAP. The mean time required for plate insertion and fixation was 15.8n (±14.4) in 3DPPA and 41.4 (±9.4, P < .001) in conventional IOAP. The mean OR charges were $1,072.5 (±524.6) in 3DPPA and $1,757.3 (±422.6, P ≤ 0.001) in conventional IOAP. The mean calculated OV of uninjured and reconstructed orbit for the 3DPPA was 23.5 (±3.2)cm3 and 23 (±3.5, P = .37)cm3, respectively. The mean calculated OV of uninjured and reconstructed orbit for conventional IOAP was 28.6 (±3.6)cm3 and 22.8 (±2.6, P < .001)cm3, respectively.

CONCLUSION AND RELEVANCE

Using 3DP to produce a model that enables preoperative plate bending/adaptation reduces the length of surgery, decreases OR charges, and results in predictable OV.

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.

Patient-specific implants for reconstruction of orbit and skull following resection of spheno-orbital meningiomas: A two-implant concept

INTRODUCTION

The surgical treatment of spheno-orbital meningioma (SOM) is challenging. In addition to anatomical constraints that lead to a difficult resection, the reconstruction of the resulting defect is demanding. Uniform recommendations concerning the best reconstruction technique are not available in the existing literature. We propose a novel two-piece concept for reconstructing post-ablative defects using patient-specific implants.

MATERIAL AND METHODS

Between 2018 and 2021, seven patients underwent SOM resection using two digitally planned patient-specific implants for orbit and skull reconstruction. To analyze the accuracy of the reconstruction, preoperative plans were merged with postoperative data sets. The clinical outcome was evaluated by comparing the pre- and postoperative exophthalmos index (EI).

RESULTS

In all cases, adequate reconstruction and a satisfactory match between the final implant position and preoperative planning were achieved. The EI was reduced in all cases from a mean of 1.27 to 1.09 (p = 0.003).

CONCLUSIONS

The proposed concept of a two-piece reconstruction after SOM resection is an excellent way to manage the concern around post-ablative defects. The current technical conditions allow for a precise, safe, and predictable reconstruction.

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.

Personalized Medicine Workflow in Post-Traumatic Orbital Reconstruction

Restoration of the orbit is the first and most predictable step in the surgical treatment of orbital fractures. Orbital reconstruction is keyhole surgery performed in a confined space. A technology-supported workflow called computer-assisted surgery (CAS) has become the standard for complex orbital traumatology in many hospitals. CAS technology has catalyzed the incorporation of personalized medicine in orbital reconstruction. The complete workflow consists of diagnostics, planning, surgery and evaluation. Advanced diagnostics and virtual surgical planning are techniques utilized in the preoperative phase to optimally prepare for surgery and adapt the treatment to the patient. Further personalization of the treatment is possible if reconstruction is performed with a patient-specific implant and several design options are available to tailor the implant to individual needs. Intraoperatively, visual appraisal is used to assess the obtained implant position. Surgical navigation, intraoperative imaging, and specific PSI design options are able to enhance feedback in the CAS workflow. Evaluation of the surgical result can be performed both qualitatively and quantitatively. Throughout the entire workflow, the concepts of CAS and personalized medicine are intertwined. A combination of the techniques may be applied in order to achieve the most optimal clinical outcome. The goal of this article is to provide a complete overview of the workflow for post-traumatic orbital reconstruction, with an in-depth description of the available personalization and CAS options.

Orbital reconstruction: a systematic review and meta-analysis evaluating the role of patient-specific implants

The purpose of this study is to execute an evidence-based review answering the following question (PICO): "Do patient-specific implants (PSI), manufactured or designed using computer-assisted technology, improve outcomes (orbital volume change, enophthalmos, diplopia, and operative duration) compared to conventional methods in orbital reconstruction following traumatic orbital injury in the adult patient population?" We performed a systematic review and meta-analysis in accordance with PRISMA guidelines. Inclusion criteria included any comparative paper whereby computer-assisted technology was used in the prefabrication or design process of implants for use in post-traumatic orbital reconstruction. Paediatric patient populations were excluded. Eight databases were systematically searched for relevant studies. Risk of bias was assessed through the NOS and RoB2 tools. Random-effects models were used to identify differences in outcomes between groups where possible. Analysis was performed using R 4.0.0. Eleven of 4784 identified studies were included, comprising 628 adult patients, with 302 and 326 patients in the patient-specific and conventional groups, respectively. Weighted mean difference between unaffected and post-operative orbital volume was 0.32 ml (SD 0.75) and 0.95 ml (SD 1.03) for patient-specific and conventional groups, respectively. Significant improvement was identified in post-operative orbital volume reconstitution with the use of PSI, compared to conventional implants, in 3 of the 5 reporting studies. Equally, post-operative enophthalmos trended towards lower severity in the patient-specific group, with 11.2% of patients affected in the patient-specific group and 19.2% in the conventional group, and operative duration was significantly reduced with the use of PSI in 3 of the 6 reporting studies. Despite a tendency to favour PSI, no statistically significant differences in key outcomes were identified on meta-analysis. Although there is some encouraging data to support improved outcomes with the use of patient-specific orbital implants in post-traumatic reconstruction, there is, at present, no statistically significant evidence to objectively support their use over conventional implants based on the currently available comparative studies. Based on the results of this study, the choice of implant used should, thus, be left to the discretion of the surgeon.