Can customized implants correct enophthalmos and delayed diplopia in post-traumatic orbital deformities? A volumetric analysis

Advances in Three-Dimensional Printing for Craniomaxillofacial Trauma Reconstruction: A Systematic Review

Craniomaxillofacial (CMF) fractures present significant challenges for plastic surgeons due to their intricate nature. Conventional methods such as autologous bone grafts have limitations, necessitating advancements in reconstructive surgery techniques. This study reviewed the use of three-dimensional printing for CMF trauma reconstruction using human studies. A systematic search of PubMed, EMBASE, and Google Scholar was conducted in February 2024 for case reports, case series, and clinical trials related to CMF trauma reconstruction using three-dimensional printing technology. The authors' systematic review included 20 studies and a total of 170 participants with CMF bone defects. In general, the authors observed low bias risk in analyzed case reports and series, serious bias risk in nonrandomized controlled trials, and moderate bias risk in randomized controlled trials. The printed objects included CMF structure model prototypes, patient-specific implants, and other custom surgical devices. Studies reveal successful outcomes, including restored facial symmetry and function, restored orbital occlusion, resolved enophthalmos and diplopia, achieved cosmetically symmetrical lower face reconstruction, and precise fitting of surgical devices, enhancing patient and surgeon comfort. However, complications such as local infection, implant exposure, and persistent diplopia were reported. Three-dimensional printed devices reduced surgery time but increased preparation time and production costs. In-house production options could mitigate these time and cost expenditures. Three-dimensional printing holds potential in CMF trauma reconstruction, addressing both functional and esthetic restoration. Nevertheless, challenges persist in implementing this advanced technology in resource-limited environments.

The impact of polydioxanone (PDS) foil thickness on reconstruction of the orbital geometry after isolated orbital floor fractures

PURPOSE

The orbital floor is frequently involved in head trauma. Current evidence on the use of reconstruction materials for orbital floor repair is inconclusive. Accordingly, this study aimed to compare the impact of polydioxanone (PDS) foil thickness on reconstruction of the orbital geometry after isolated orbital floor fractures.

METHODS

Standardized isolated orbital floor fractures were symmetrically created in 11 cadaver heads that provided 22 orbits. PDS foils with thicknesses of 0.25-0.5 mm were inserted. Computed tomography (CT) scans of the native, fractured, and reconstructed orbits were obtained, and orbital volume, orbital height, and foil bending were measured.

RESULTS

Orbital volume and height significantly (p < 0.01) increased after the creation of isolated orbital floor fractures and significantly (p = 0.001) decreased with overcorrection of the orbital geometry after orbital floor reconstruction with PDS 0.25 mm or PDS 0.5 mm. The orbital geometry reconstruction rate did not differ significantly with respect to foil thickness. However, compared to PDS 0.5 mm, the use of PDS 0.25 mm resulted in quantitatively higher reconstructive accuracy and a restored orbital volume that did not significantly differ from the initial volume.

CONCLUSION

Orbital floors subjected to isolated fractures were successfully reconstructed using PDS regardless of foil thickness, with overcorrection of the orbital geometry. Due to its lower flexural stiffness, PDS 0.25 mm appeared to provide more accurate orbital geometry reconstruction than PDS 0.5 mm, although no significant difference in reconstructive accuracy between PDS 0.25 mm and PDS 0.5 mm was observed in this cadaveric study.

Virtual Surgical Planning and 3-Dimensional Printing for the Treatment of Zygomaticomaxillary Complex and/or Orbital Fracture

BACKGROUND

Traditionally, in zygomaticomaxillary complex and orbital fractures, miniplates and titanium orbital mesh are used and adapted intraoperatively, which may cause fatigue of the metal and increase the surgical time. Recently, computer-assisted surgery and 3-dimensional printing enable the surgeon to employ 3-dimensional segmentation and mirroring tools, which mimic the pretraumatized anatomy on which the miniplates and titanium orbital mesh are preoperatively molded to precisely duplicate the orbital volume, enophthalmos, and zygomatic bone position.

AIM

To evaluate the results of computer technology using 3-dimensional printing model to prebend miniplates and titanium orbital mesh in the restoration of orbital volume, enophthalmos, and zygomatic bone position in the initial management of patients with zygomaticomaxillary complex and/or orbital fractures.

PATIENTS AND METHODS

This prospective clinical study included 10 Iraqi male patients who met the eligibility criteria and subjected to open reduction and internal fixation utilizing virtual surgical planning and a 3-dimensional model to prebend miniplates and titanium orbital mesh as a treatment modality for facial fractures. The data were analyzed according to the orbital volume, enophthalmos, zygomatic bone position, age, gender, etiology of the fracture, and complications. The patients were radiographically followed up with a computed tomography scan at 4 months postoperatively. The statistical analysis was performed using percentages, the mean±SD, Shapiro-Wilk test, Paired t test, One Way Anova, and Independent t test.

RESULTS

The age of the patients ranged from 18 to 66 years, with an average of 28.6 years and a SD of±14.5 years. Regarding gender, all patients were males. By utilizing virtual surgical planning and 3-dimentional model to prebend miniplates and titanium orbital mesh and concerning the fracture types, which include the zygomaticomaxillary complex, orbital, and combined fractures, there was no significant difference between the measurement of intact side and 4 months postoperatively in orbital volume, enophthalmos, and zygomatic bone position ( P >0.05).

CONCLUSION

This study demonstrated that computer-aided techniques, virtual planning, and the use of prebend miniplates and titanium orbital mesh enable anatomically precise reduction and fixation of the orbital, zygomaticomaxillary complex, and combined fractures regarding orbital volume, enophthalmos, and zygomatic bone position.

Patient Specific Implants for Orbital Reconstruction in the Treatment of Silent Sinus Syndrome: Two Case Reports

Silent sinus syndrome is a rare disorder characterized by ipsilateral enophthalmos and hypoglobus following a collapse of the orbital floor, in the presence of asymptomatic long-term maxillary sinusitis. It results in enophthalmos, hypoglobus and deepening of the superior palpebral sulcus. A standardized treatment protocol for this infrequent syndrome has not yet been established. The management includes restoration of maxillary sinus ventilation with functional endoscopic sinus surgery and orbital reconstruction, either concurrently or separately. In this paper, the authors presented two patients successfully treated with patient-specific implants, and intraoperative navigation. These cases highlight the benefit of computer-assisted planning and titanium patient-specific implants in the management of silent sinus syndrome. To the best of our knowledge, this is the first report that described the use of PSI with titanium spacers performed with the aid of intraoperative navigation for SSS treatment. Advantages, drawbacks of this technique and treatment alternatives currently available in the literature were also discussed.

Technical considerations of computer-aided planning in severe orbital trauma: A retrospective study

The aim of this study was to evaluate the clinical outcomes of linear and orbital volume measurements in severe orbital trauma. Patients with severe orbital trauma that involved more than two walls and entailed a marked degree of comminution were included in this retrospective analysis. However, patients with incomplete clinical records and a simple blowout or zygmatico-orbital fractures were excluded. All the cases underwent surgical correction guided by virtual surgical planning and 3D-printed templates. The measurement protocol depended on assessing orbital dimensions, orbital volumetry, and the zygomatic bone's position in the three-dimensional planes. All patients' preoperative 3D CT scans were obtained, and DICOM files were imported into a three-dimensional image processing software. Data were then converted for 3D reconstruction in the axial, coronal, and sagittal views. A total of 18 patients with a mean age was 39.28 ± 6.28 were included in this study. The results revealed a significant difference between the pre and postoperative differences in distances in relation to the FHP (Frankfurt Horizontal Plane) (P = 0.0014) and sagittal planes (P < 0.0001). The orbital width and height of the traumatized orbit were significantly decreased from 45.26 ± 6.72 mm and 45.30 ± 2.89 mm to 39.74 ± 3.91 mm (P = 0.0022), and 40.34 ± 0.86 mm (P < 0.0001), respectively. Clinically, there was a satisfactory degree of symmetry regarding the zygomatic bones' position and orbital dimensions postoperatively. Moreover, the mean orbital volume on the traumatized side decreased significantly from 23.16 ± 1.91 cm³ preoperatively to 20.7 ± 1.96 cm³ postoperatively (P < 0.0001). These findings were associated with a low incidence of complications. Within the limitations of the study it seems that the described methodology is a relevant addition to clinical treatment options. It incorporates all the latest technology to plan virtual reconstruction surgery in the treatment of complex orbital trauma and should be adapted accordingly in cases of severe displacement and comminution.

[Current developments in primary and secondary surgical treatment of midface and periorbital trauma]

Fractures of the periorbita and the midface are among the most common bony facial injuries. Aesthetic and functional reconstruction is a challenge in clinical routine. This article illustrates recent developments in the primary and secondary surgical treatment of midface and periorbital trauma. Resorbable patches and films increase the anatomic reconstructive capacity and enable treatment of extensive orbital fractures. Orbital fractures with involvement of supporting key structures are advantageously reconstructed using patient-specific implants (PSI), which are fabricated by computer-assisted manufacturing techniques and positioned by intraoperative navigation. If late complications such as bulbar malposition and enophthalmos have occurred after the initial procedure, they can be addressed by overcorrective restoration of orbital volume. The use of PSI for initial fracture restoration of the midface is not yet established but may be useful in re-osteotomies of misconsolidated fragments. Extensive midface defects with significant soft tissue involvement can be reconstructed using microvascular grafts. Consecutive reconstructive procedures may include orthognathic surgery and local flap reconstruction. In summary, the integration and advancement of computer-assisted techniques now offers individualized reconstruction procedures, which may be a viable alternative to conventional implants and compression miniplates. Future developments may focus on the search for innovative biomaterials, which can be integrated into computer-aided design and manufacturing processes.

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.

Primary reconstruction of extensive orbital fractures using two-piece patient-specific implants: the Helsinki protocol

PURPOSE

We present our experience of titanium-milled two-piece patient-specific implants (PSIs) for primary reconstructions of extensive orbital floor and medial wall fractures (EOFMFs) and evaluate their postoperative functional and aesthetic outcomes in relation to commercially available implants.

METHODS

We included all patients with primary reconstructions (< 22 days from injury) of EOFMFs treated in our department between January 2011 and October 2020. Extensive orbital floor and medial wall fracture was defined as involvement of orbital floor, medial wall and maxilloethmoidal junction; a fracture defect 5 mm or more; defect size more than a third of both inferior and medial walls; and Jaquiéry classification III or more. Patient characteristics, details of fracture defects and surgeries, postoperative outcomes and implant positions were retrospectively evaluated and compared between study groups.

RESULTS

Nineteen patients were included: 5 with two-piece PSIs and 14 with commercial implants. Implant position was good in 4/5 patients with two-piece PSIs and 2/14 with commercial implants. Revision surgery, globe malposition (GMP) > 2 mm, significant diplopia and poor implant position were more frequent in patients with commercial implants than two-piece PSIs. None of the patients with a good overall implant position had any significant postoperative symptoms.

CONCLUSION

Extensive orbital fracture reconstructions are somewhat rare, and surgical treatment is associated with a high rate of complications and postoperative symptoms. Titanium-milled two-piece PSIs are well suited for primary reconstructions of EOFMFs, as they lead to more precise reconstructions and fewer postoperative symptoms than commercially available implants.

Critical appraisal of patient-specific implants for secondary post-traumatic orbital reconstruction

In orbital reconstruction, a patient-specific implant (PSI) may provide accurate reconstruction in complex cases, since the design can be tailored to the anatomy. Several design options may be embedded, for ease of positioning and precision of reconstruction. This study describes a cohort of 22 patients treated for secondary orbital reconstruction with a PSI; one patient received two PSI. The preoperative clinical characteristics and implant design options used are presented. When compared to preoperative characteristics, the postoperative clinical outcomes showed significant improvements in terms of enophthalmos (P < 0.001), diplopia (P < 0.001), and hypoglobus (P = 0.002). The implant position in all previous reconstructions was considered inadequate. Quantitative analysis after PSI reconstruction showed accurate positioning of the implant, with small median and 90th percentile deviations (roll: median 1.3°, 90th percentile 4.6°; pitch: median 1.4°, 90th percentile 3.9°; yaw: median 1.0°, 90th percentile 4.4°; translation: median 1.4 mm, 90th percentile 2.7 mm). Rim support proved to be a significant predictor of roll and rim extension for yaw. No significant relationship between design options or PSI position and clinical outcomes could be established. The results of this study show the benefits of PSI for the clinical outcomes in a large cohort of secondary post-traumatic orbital reconstructions.

Clinical outcome of patients with orbital fractures treated with patient specific CAD/CAM ceramic implants - A retrospective study

The aim of this study was to determine whether patients benefit from a secondary reconstruction since it carries the risks of no improvement or worsening of their current situation. Patients treated with individual computer-aided-design/computer-aided-manufacturing (CAD/CAM) ceramic implants were reviewed. To ascertain changes throughout the secondary reconstruction, the study investigators reviewed ophthalmological examinations, took volumetric measurements of the orbits and asked the patients for evaluation of their situation before and after the reconstruction. Points addressed were double vision, visual acuity, field of vision, limitations in daily life and aesthetic considerations. A total of 14 patients were reviewed and 11 answered the questionnaire. Ophthalmological examinations showed that the physical integrity of the eye was maintained. Volumetric measurements preopeatively (33.94 ± 3.24 cm³) and postoperatively (30.67 ± 2.07 cm³) showed that a statistically significant overcorrection of orbital volume leads to good functional and aesthetic outcomes. Patients' subjective opinions were that they greatly benefitted, especially concerning limitations in daily life, which improved by 4.4 ± 2.8 points out of 10 possible points, and aesthetics, with an improvement of 5.9 ± 1.78 points. Based on these findings, we conclude that secondary reconstructions contribute to improvement of the patients' quality of life and therefore should be considered as an option to improve patients' condition.

Prediction of Post-Traumatic Enophthalmos Based on Orbital Volume Measurements: A Systematic Review

PURPOSE

Enophthalmos greater than 2 mm should be considered clinically relevant and can be responsible for esthetic and functional morbidity. The difficulty has always been the best method to use to accurately determine when the orbital wall displacement will lead to clinically relevant enophthalmos. None of the currently used techniques is able to accurately predict for post-traumatic enophthalmos (PE). The aim of the present study was to systematically review the use of orbital volumetric tools in the prediction of PE after orbital fracture.

MATERIALS AND METHODS

The terms searched in each database were "(orbital volumetry) and enophthalmos," "volumetry and enophthalmos," "volume and enophthalmos," and "volumetric and enophthalmos." The relationship between PE and the orbital volume (OV) was assessed.

RESULTS

The initial search yielded 346 results. Of the 346 studies, 14 were included and analyzed. Every study reported a different numerical relationship between the OV and PE, with a mean enophthalmos of 0.80 mm after a 1-cm³ increase in the OV.

CONCLUSIONS

The present review found that most studies concluded that a direct relationship exists between the OV and PE and defined the degree of PE in relation to the OV expansion. Enophthalmos assessment using radiologic evaluation provides increased accuracy and reproducibility compared with clinical measurement using an exophthalmometer. It has been notoriously difficult to determine when orbital wall displacement will lead to clinically relevant enophthalmos. Measurement of the OV could have a role in the decision for surgical or conservative treatment.

Overview of tools for the measurement of the orbital volume and their applications to orbital surgery

There are numerous applications in craniofacial surgery with orbital volume (OV) modification. The careful management of the OV is fundamental to obtain good esthetic and functional results in orbital surgery. With the growth of computer-aided design - computer-aided manufacturing (CAD-CAM) technologies, patient-specific implants and custom-made reconstruction are being used increasingly. The precise measurement of the OV before surgery is becoming a necessity for craniofacial surgeons. There is no consensus on orbital volume measurements (OVMs). Manual segmentation of computed tomography (CT) images is the most used method to determine the OV, but it is time-consuming and very sensitive to operator errors. Here, we describe the various methods of orbital volumetry validated in the literature that can be used by surgeons in preoperative planning of orbital surgery. We also describe the leading software employed for these methods and discuss clinical use (posttraumatic enophthalmos prediction and orbital reconstruction) in which OVMs are important.

Evaluation of orbital volume after orbitozygomatic complex fractures fixation: A radiographical study

Background

Orbitozygomatic complex fractures are one of the most commonly encountered injuries of the craniofacial skeleton. The aim of this study was to implement the orbital volume as an objective evaluation modality for the assessment of the accuracy of unilateral Orbitozygomatic complex fracture fixation, by comparing the postoperative values with the contralateral normal side and the pretreated values.

Materials and methods

A retrospective radiographic, chart review was performed in order to investigate the primary outcome of the objective quantification of the accuracy of Orbitozygomatic complex fracture reduction utilizing orbital volume analysis. Comparing the postoperative orbital volume values with the preoperative, and the contralateral normal ones was set as the study secondary outcome, along with the percentage of changes in the orbital volume of unilateral Orbitozygomatic complex fracture treated patients. Data reliability was performed using Interclass correlation coefficient and Statistical significance was set at 5% level.

Results

Seventeen records met the inclusion criteria. While a statistically significant difference was found between the preoperative orbital volume values of the affected side and that in the normal unaffected side (P < 0.001), a statistically insignificant difference was encountered between the postoperative values and the control side (P = 0.333). An average percentage of decrease of 6.1%. was reported in the postoperative records when compared to the preoperative ones, with a statistically significant difference (P < 0.001). the study reported high inter (ICC = 0.97) and Intra (ICC = 0.97) observer reliability.

Conclusion

Orbital volume analysis offers a valid modality for the objective evaluation of the efficiency of Orbitozygomatic complex fracture management.

Post-traumatic enophthalmos secondary to orbital fat atrophy: a volumetric analysis

PURPOSE

To investigate via volumetric analysis whether orbital fat atrophy occurs in late post-traumatic enophthalmos.

METHODS

An IRB-approved retrospective cohort study identified patients with diagnoses of both orbital fracture and enophthalmos with a CT orbits >3 months after injury. Exclusion criteria were surgical repair, other orbital disease or surgery, adjacent sinus disease, and an abnormal contralateral orbit. Images were analyzed using OsiriX imaging software (v.9.0.2, Pixmeo, Switzerland). Total orbital volume and orbital fat volume for the fractured and normal contralateral orbits were measured via three-dimensional volume rendering assisted region-of-interest computation. Enophthalmos was measured radiographically. Paired samples t-tests were used to compare orbital fat and total orbital volumes between the fractured and normal contralateral orbits.

RESULTS

Thirteen patients met the inclusion criteria. The numbers of patients with each fracture pattern were floor (4), medial wall (4), floor/medial wall (3), zygomaticomaxillary complex (floor+lateral wall) (1), zygomaticomaxillary complex+medial (inferior/medial/lateral walls) (1). Mean time from injury to CT scan was 21.8 ± 16.3 months. Comparing the fractured and normal contralateral orbits, there was a statistically significant decrease in orbital fat volume (mean difference 0.9 ml (14.2%), p = .0002) and increase in total orbital volume (mean difference 2.0 ml (7.0%), p = .0001). One ml orbital volume change was responsible for 0.83 mm enophthalmos.

CONCLUSIONS

In addition to an increase in total orbital volume, orbital fat loss occurs with late post-traumatic enophthalmos due to unrepaired fractures. This suggests correction of bony change alone may be insufficient in some cases, and the use of custom implants may compensate for fat atrophy.

Craniomaxillofacial patient-specific CAD/CAM implants based on cone-beam tomography data - A feasibility study

Customized implants have simplified surgical procedures and have improved patient outcome in craniomaxillofacial surgery. Traditionally, patient-specific data is gathered by conventional computed tomography (CT). However, cone-beam CT (CBCT) can generate a 3D reconstruction of the area of interest with a lower dose of radiation at reduced cost. In this study, we investigated the feasibility of using CBCT data to design and generate customized implants for patients requiring craniomaxillofacial reconstruction. We used CBCT to generate 62 implants for 51 consecutive patients admitted to our department between January 2015 and December 2017. The indications for reconstruction and types of reconstruction were very variable. In all cases, the implants were well fitted and no implant-related complications were detected. Pre-surgical planning was faster and more efficient as we did not have to consult a radiologist. Although CBCT data is more difficult to process than conventional CT data for the implant provider, the clinical advantages are pronounced and we now use CBCT as standard in our department. In conclusion, we have shown that using CBCT to design and manufacture customized implants for reconstruction of the craniomaxillofacial area is feasible and recommend this approach to other departments.

Correction of Delayed Traumatic Enophthalmos Using Customized Orbital Implants

PURPOSE

To determine the relation between overcorrection of orbital volume and ocular projection in patients with orbital trauma.

MATERIALS AND METHODS

A prospective cohort study was performed of patients with enophthalmos as a side effect of orbital trauma. The sample included patients older than 18 years who required reconstruction using customized implants to treat enophthalmos with or without diplopia. The exclusion criteria were patients who had multiple or extended fractures and patients with amaurosis or a prosthetic eye. Orbital volumes were calculated and the position of the eyeball in the healthy and traumatized sockets was determined before and after installing the implant and the ratio between these variables was calculated. Two variables were identified: 1) orbital volume and 2) enophthalmos. Analysis of the estimator variables was performed, defining 3 groups: 1) healthy eye socket, 2) traumatized eye socket without implant, and 3) traumatized eye socket with implant. The Shapiro-Wilk test, paired t test, and linear regression analysis were performed. A P value less than .05 (95% confidence interval) indicated significant differences.

RESULTS

Of 294 patients who underwent orbital zygomatic complex reconstruction surgery, 13 required customized implants and only 5 met the inclusion criteria. The average volumetric variation in the groups of traumatized eye sockets with and without implants was statistically significant (P < .05), overcorrecting by an average of 4.2 cm³. The average enophthalmos variation in the groups of traumatized eye sockets with and without implants was statistically significant (P < .05), projecting the eyeball by an average 1.80 mm. The ratio between the average orbital volume and projection of the eyeball was determined to be 1:0.721 (correlation, 45.6%).

CONCLUSION

This study concluded that the eyeball is projected 0.7 mm for every 1 cm³ of volume added in customized orbital implants. However, additional clinical studies with larger samples should be conducted.

Resolution of Diplopia in Late Repair of Enophthalmos Following Facial Trauma

Posttraumatic enophthalmos due to isolated or complex orbital fractures can contribute to diplopia. Current evidence recommends early repair. However, little is known about the outcome of enophthalmos correction when repair occurs beyond 30 days after trauma. In this systematic review, the authors aim to evaluate the current evidence on functional outcomes after delayed repair of posttraumatic enophthalmos.Two independent assessors undertook a systematic review of the literature using multiple databases. The authors' inclusion criteria identified studies involving patients at least 14 years of age who had surgical correction of persistent enophthalmos 30 days after initial trauma. Each eligible paper was included after critical appraisal using validated guidelines. Data on preoperative and postoperative enophthalmos and diplopia in each study was extracted. The pattern of fracture was also noted.The authors' search for the medical databases yielded 1053 articles, of which 6 eligible papers were included. Meta-analysis was performed. In patients with complex injuries involving orbital and mid-facial fractures, diplopia resolution was calculated to be 53%, and enophthalmos was corrected in 83% of the patients. In patients with isolated orbital fractures, 53% had resolution of their diplopia, and enophthalmos was corrected in 88% of the patients.Enophthalmos can be corrected to within 2 mm of the contralateral eye in both the isolated and complex orbital fractures in patients who present 30 days or greater after injury. Based on the studies reviewed, there is less predictability in diplopia resolution.

Three dimensional reconstruction of late post traumatic orbital wall defects by customized implants using CAD-CAM, 3D stereolithographic models: A case report

Aim

Purpose of this case report is to highlight the precision and accuracy obtained with patient specific implants for orbital reconstruction designed on the basis of volumetric analysis of orbital computed tomographic scan (CT) scans using virtual planning, computerised designing and manufacturing and stereolithographic models to correct late post-traumatic orbital deformities such as enophthalmos and diplopia.

Material and methods

This case report describes a patient who visited our outpatient clinic for correction of enophthalmos and persistent diplopia in upward gaze, seven months post trauma. Three dimensional (3D) virtual treatment planning was carried out by using the 3D CT data. The unaffected orbit of the contralateral side was superimposed on the deformed orbit to highlight the defect and a customized implant was designed in the desired size and shape on the virtual model using computer aided designing and manufacturing (CAD-CAM) and milled in titanium mesh for precise anatomic orbital reconstruction.

Results

There was a marked improvement in both the diplopia in upward gaze and enophthalmos post surgery when the customized patient specific orbital implant was used.

Conclusion

The concept of using customized implant with the help of 3D virtual treatment planning, 3D stereolithographic models and CAD-CAM greatly improves the correction of extremely difficult late post-traumatic orbital deformities.