A case series of rapid prototyping and intraoperative imaging in orbital reconstruction

Advances in Personalized Orbital Implants for Surgical Repair and Reconstruction

Adopting digital workflows in orbital reconstruction enhances surgical precision, minimizes complications, and improves patient outcomes postoperatively. Personalized orbital implants (POIs), tailored to each patient's specific anatomy, offer superior functional and esthetic restoration compared with traditional stock implants. However, widespread adoption of POI is limited by high costs, low-resource settings, untrained personnel, and regulatory concerns, underscoring the continued necessity of traditional methods. This article provides insight into POI in orbital reconstruction, covering key advancements in digital planning, biomaterials, surgical techniques, and strategies for balancing technological innovations with clinical validation.

Orbital Fractures Treated in Auckland From 2016 to 2020: Review of Patient Outcomes

Orbital reconstruction is a complex procedure demanding accurate placement of implants to restore volume and anatomic shape to the orbits. Intra-operative computed-tomography (CT) and rapid-prototype (RP) biomodels have been recently introduced as surgical aids to improve outcomes. Investigation is required to determine if there is a reduction in post-operative ophthalmic complications.

Study Design

Retrospective cohort study.

Objective

To evaluate the impact of intra-operative CT and RP biomodels on the incidence of post-operative diplopia, paraesthesia, cosmetic issues and ability to return to work following orbital reconstruction surgery.

Methods

Adult (>18 years) patients treated at Counties Manukau District Health Board, Auckland, by the Department of Oral and Maxillofacial Surgery for isolated orbital fractures were retrospectively enrolled into this study. An audit of clinical records was undertaken to determine incidences of diplopia, altered sensation, cosmetic concerns and ability to return to work. These findings were compared against our previous audit which documented these findings in patients treated between 2010 and 2015, prior to the introduction of intra-operative CT and RP biomodels.

Results

Routine use of intra-operative CT and RP biomodels was associated with a reduced incidence of post-operative diplopia. No significant difference was observed with regards to paraesthesia and cosmetic deficits.

Conclusions

The relatively low radiation exposure and cost associated with intra-operative CT and RP biomodels is justified with improved outcomes in subjective diplopia. Titanium as a material for orbital reconstruction was confirmed to be associated with low complication rates.

The Use and Outcomes of 3D Printing in Pediatric Craniofacial Surgery: A Systematic Review

Three-dimensional (3D) printing has demonstrated efficacy in multiple surgical specialties. As accessibility improves, its use in specific fields deserves further attention. We conducted a systematic review of the implementation and outcomes of 3D printing in pediatric craniofacial surgery, as none has been performed. A systematic review was conducted according to Cochrane and PRISMA guidelines. PubMed, Embase, Cochrane library, and Clinicaltrials.gov were queried with combinations of the terms: "3D printing," "craniofacial," "surgery," and "pediatric." Original human studies containing patients <18 years old implementing 3D printing to aid in craniofacial surgery were included. Study selection, grading, and data extraction were performed independently by multiple authors. After screening 120 articles, 7 (3 case series and 4 case reports) were included, published from 2017 to 2022. All studies addressed patients with different disease processes including craniosynostosis, cleft lip/palate, and mandibular hypoplasia. 3D printing was used to create mock surgical models in 2 studies, intraoperative cutting guides/molds (CGs) in 6 studies, and cranioplasty implants in 2 studies. Two case series determined the accuracy of the CGs was acceptable within historical comparison, while 4 articles included subjective statements on improved accuracy. Five studies noted reduced operating time, 2 noted reduced intraoperative blood loss, and 1 felt the use of 3D printed materials was responsible for shorter hospitalization duration. No adverse events were reported. Despite the limitations of the current literature, all studies concluded that the use of 3D printing in pediatric craniofacial surgery was beneficial. Definitive conclusions cannot be made until further controlled research is performed.

Intraoperative computed tomography for orbital reconstruction: a systematic review

Orbital reconstruction is a common procedure with inherent challenges and important consequences. Intraoperative use of computed tomography (CT) is an emerging application that facilitates accurate intraoperative evaluation to improve clinical outcomes. This review aims to investigate the intraoperative and postoperative outcomes of intraoperative CT use in orbital reconstruction. PubMed and Scopus databases were systematically searched. Inclusion criteria were: clinical studies investigating intraoperative CT use in orbital reconstruction. Exclusion criteria were: duplicates; non-English publications; non-full-text publications; studies with insufficient data. Of the 1022 articles identified, seven eligible articles representing 256 cases were included. The mean age was 39 years. Most cases were male (69.9%). With regards to intraoperative outcomes, the mean revision rate was 34.1%, with plate repositioning being the most common type (51.1%). Intraoperative time was variably reported. With regards to postoperative outcomes, there were no revisions, and only one case that had a complication (transient exophthalmos). Mean volumetric difference between the repaired and contralateral orbits was reported in two studies. The findings of this review present an updated evidence-based summary of the intraoperative and postoperative outcomes of intraoperative CT use in orbital reconstruction. Robust longitudinal comparisons of clinical outcomes between intraoperative and non-intraoperative CT cases are required.

Utilizing 3D Printing for the Surgical Management of Orbital Floor Fractures

We present a technique for treating orbital floor fractures using three-dimensional (3D) printing technology and a preoperative template based on the mirror image of the unaffected orbit. Our patient, a 56-year-old man, experienced persistent diplopia in the upward direction and left enophthalmos after previous open reduction internal fixation surgery. To address these complications, we used a simulation of the ideal orbital floor from computed tomography images and used a 3D printer to create a template. Subsequently, an absorbable plate was molded intraoperatively based on this template. Notably, the plate fit seamlessly into the fracture site without requiring any adjustment, reducing the operation time. Postoperative computed tomography scans confirmed successful reduction, improved visual function, and the absence of complications. Our method offers a precise and efficient approach to reconstructing fractured orbital floors. By leveraging 3D printing technology and preoperative templates, surgeons can enhance postoperative outcomes and minimize patient burden. Further investigations are warranted to assess the long-term effectiveness and cost-effectiveness of this technique. Our findings highlight the potential of this approach to improve treatment strategies for patients with orbital floor fractures.

Outcome of Precontoured Titanium Mesh in the Reconstruction of Orbital Blowout Fractures

Background Orbital blowout fractures are peculiar injuries causing disruption of both ocular function and symmetry. We present our experience with the use of a precontoured titanium mesh in orbital blowout fractures.

Methods A retrospective study of patients undergoing correction of orbital blowout fractures with a precontoured titanium mesh was done at a tertiary care center in Mumbai. Data regarding demographics and pre- and postoperative clinical and radiological attributes were retrieved and compared.

Results A total of 21 patients (19 males and 2 females) underwent correction of blowout fractures with a precontoured titanium mesh. The follow-up period ranged from 6 to 10 months. Road traffic accident (76%) was the most common etiology. Twenty (95%) patients had impure blowout fractures and 1 (5%) patient had a pure blowout. The orbital floor was most commonly fractured (16 [76%]). Associated fractures of the zygomaticomaxillary complex were found in 71% of patients. All patients were operated on within 3 weeks of trauma. A comparison of the operated and uninjured sides on coronal views of computed tomography (CT) scan in nine patients by Photopea application revealed a correction of the increased cross-sectional area in all cases. Enophthalmos was completely corrected in 94% patients, while 92% patients had complete correction of diplopia. One patient with a comminuted zygomatic fracture had persistent diplopia and mild enophthalmos. Infraorbital paresthesia persisted in 58% patients at 6 months of follow-up. No significant postoperative complications were noted.

Conclusion The precontoured titanium mesh restores orbital wall anatomy and is safe, quick, fairly easy, and reproducible with a shorter learning curve. With proper patient selection and execution, prefabricated titanium mesh can serve as an excellent reconstructive option in blowout fractures of the orbit.

A Literature Review of Rapid Prototyping and Patient Specific Implants for the Treatment of Orbital Fractures

Post-traumatic reconstruction of the orbit can pose a challenge due to inherent intraoperative problems. Intra-orbital adipose tissue is difficult to manipulate and retract making visualization of the posterior orbital contents difficult. Rapid prototyping (RP) is a cost-effective method of anatomical model production allowing the surgeon to produce a patient specific implant (PSI) which can be pre-surgically adapted to the orbital defect with exact reconstruction. Intraoperative imaging allows immediate assessment of reconstruction at the time of surgery. Utilization and combination of both technologies improves accuracy of reconstruction with orbital implants and reduces cost, surgical time, and the rate of revision surgery.

Establishing a point-of-care additive manufacturing workflow for clinical use

Additive manufacturing, or 3-Dimensional (3-D) Printing, is built with technology that utilizes layering techniques to build 3-D structures. Today, its use in medicine includes tissue and organ engineering, creation of prosthetics, the manufacturing of anatomical models for preoperative planning, education with high-fidelity simulations, and the production of surgical guides. Traditionally, these 3-D prints have been manufactured by commercial vendors. However, there are various limitations in the adaptability of these vendors to program-specific needs. Therefore, the implementation of a point-of-care in-house 3-D modeling and printing workflow that allows for customization of 3-D model production is desired. In this manuscript, we detail the process of additive manufacturing within the scope of medicine, focusing on the individual components to create a centralized in-house point-of-care manufacturing workflow. Finally, we highlight a myriad of clinical examples to demonstrate the impact that additive manufacturing brings to the field of medicine.

Intraoperative Computed Tomography Image Fusion for Orbital Blowout Fracture Reconstruction

Intraoperative computed tomography (CT) has been previously described and acknowledged for its use in orbital blowout fracture reconstructions. We described a clinical case series managed by this technique combined with intraoperative image fusion for accuracy in orbital implant position. In total, eight patients who sustained a total number of 19 orbital wall fractures were described. From the total number of 19 blowout orbital fracture reconstructions comprised of medial and inferior (floor) orbital fractures, malposition was identified in a total of four orbital implants by using image fusion. All cases of implant malposition were immediately revised intraoperatively. Subsequent fusion was carried out to confirm whether the revision was satisfactorily achieved. We found that the intraoperative image fusion technique utilised to determine orbital implant position, especially at the posterior ledge, further augmented the role of intraoperative CT scanning. Image fusion conceptually provides an immediate, real-time, and objective solution for intraoperative image analysis and potentially eliminates problems with misaligned CT images. It also reduces the need for the surgeon to ‘eye-ball’ the CT images acquired or the need for additional intraoperative time, since the patient’s head orientation is always axially at random during the acquisition of the CT. Conventional methods for CT image assessment are subjected to one’s own interpretation and may introduce inconsistent or longer intraoperative decision-making. The technique facilitates intraoperative decision-making and reduces the risk of orbital implant malposition in orbital blowout fracture reconstructions. Hence, surgical complication in relation to orbital implant malposition in orbital blowout fracture management could be minimised. In addition, no further postoperative imaging is required.

The use of a 3D-printed individualized navigation template to assist in the anatomical reconstruction surgery of the anterior cruciate ligament

Background

To explore the location accuracy and early clinical outcomes of using a 3D-printed individualized navigation template to assist in the reconstruction of the anterior cruciate ligament (ACL).

Methods

A single center randomized control study was conducted. Patients with ACL injury were treated with a conventional operation or an operation assisted by a 3D-printed individualized navigation template (the 3D group). The primary endpoint was the accuracy of the actual reconstruction compared with the planned position.

Results

There were 20 and 23 participants in the conventional group and the 3D group, respectively. There were no differences in the bone tunnel position between the actual postoperative position and the preoperative design in the 3D group (P>0.05). Compared with the 3D group, the positioning of the femoral tunnel was more inferior and shallower in the conventional group (P<0.05). The position of the tibia tunnel was closer to the anterior and medial edge of the tibial platform in the conventional group compared to the 3D group (P<0.05). The intraoperative positioning time was shorter in the 3D group than in the conventional group (3.3±1.0 vs. 5.9±1.8 minutes, P<0.001). The Lysholm and International Knee Documentation Committee scores did not differ between the two groups (P>0.05 for both), and all patients improved after surgery (P<0.001).

Conclusions

The 3D-printed individualized navigation template showed good location accuracy and resulted in reduced intraoperative positioning time compared to the traditional method for ACL reconstruction.

3D printed bone models in oral and cranio-maxillofacial surgery: a systematic review

AIM

This systematic review aimed to evaluate the use of three-dimensional (3D) printed bone models for training, simulating and/or planning interventions in oral and cranio-maxillofacial surgery.

MATERIALS AND METHODS

A systematic search was conducted using PubMed® and SCOPUS® databases, up to March 10, 2019, by following the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) protocol. Study selection, quality assessment (modified Critical Appraisal Skills Program tool) and data extraction were performed by two independent reviewers. All original full papers written in English/French/Italian and dealing with the fabrication of 3D printed models of head bone structures, designed from 3D radiological data were included. Multiple parameters and data were investigated, such as author's purpose, data acquisition systems, printing technologies and materials, accuracy, haptic feedback, variations in treatment time, differences in clinical outcomes, costs, production time and cost-effectiveness.

RESULTS

Among the 1157 retrieved abstracts, only 69 met the inclusion criteria. 3D printed bone models were mainly used as training or simulation models for tumor removal, or bone reconstruction. Material jetting printers showed best performance but the highest cost. Stereolithographic, laser sintering and binder jetting printers allowed to create accurate models with adequate haptic feedback. The cheap fused deposition modeling printers exhibited satisfactory results for creating training models.

CONCLUSION

Patient-specific 3D printed models are known to be useful surgical and educational tools. Faced with the large diversity of software, printing technologies and materials, the clinical team should invest in a 3D printer specifically adapted to the final application.

Application of the Guiding Template Designed by Three-dimensional Printing Data for the Insertion of Sacroiliac Screws: a New Clinical Technique

This study is aimed to explore the clinical application of the guiding template designed by three-dimensional printing data for the insertion of sacroiliac screws. A retrospective study of 7 cases (from July 2016 to December 2016), in which the guiding template printed by the threedimensional printing technique was used for the insertion of sacroiliac screws of patients with posterior ring injuries of pelvis, was performed. Totally, 4 males and 3 females were included in template group, aged from 38 to 65 years old (mean 50.86±8.90). Of them, 5 had sacral fractures (3 with Denis type I and 2 with type II) and 2 the separation of sacroiliac joint. Guiding templates were firstly made by the three-dimensional printing technique based on the pre-operative CT data. Surgical operations for the stabilization of pelvic ring by applying the guiding templates were carried out. A group of 8 patients with sacroiliac injuries treated by percutaneous sacroiliac screws were analyzed as a control group retrospectively. The time of each screw insertion, volume of intra-operative blood loss, and the exposure to X ray were analyzed and the Matta's radiological criteria were used to evaluate the reduction quality. The Majeed score was used to evaluate postoperative living quality. The visual analogue scale (VAS) was applied at different time points to judge pain relief of coccydynia. All the 7 patients in the template group were closely followed up radiographically and clinically for 14 to 20 months, mean (16.57±2.44) months. Totally 9 sacroiliac screws for the S1 and S2 vertebra were inserted in the 7 patients. The time length for each screw insertion ranged from 450 to 870 s, mean (690.56±135.68) s, and the number of times of exposure to X ray were 4 to 8, mean (5.78±1.20). The intra-operative blood loss ranged from 45 to 120 mL, mean (75±23.32) mL. According to Matta's radiology criteria, the fracture and dislocation reduction were excellent in 6 cases and good in 1. The pre-operative VAS score ranged from 5.2 to 8.1, mean (7.13±1.00). The average one-week/six-month post-operative VAS was (5.33±0.78) and (1.33±0.66), respectively (P<0.05 when compared with pre-operative VAS). The 12-month postoperative Majeed score ranged from 86 to 92, mean (90.29±2.21). The three-dimensional printed guiding template for sacroiliac screw insertion, which could significantly shorten the operation time, provide a satisfied outcome of the stabilization of the pelvic ring, and protect doctors and patients from X-ray exposure, might be a practical and valuable new clinical technique.

Feasibility and Validity of Printing 3D Heart Models from Rotational Angiography

Rotational angiography (RA) has proven to be an excellent method for evaluating congenital disease (CHD) in the cardiac cath lab, permitting acquisition of 3D datasets with superior spatial resolution. This technique has not been routinely implemented for 3D printing in CHD. We describe our case series of models printed from RA and validate our technique. All patients with models printed from RA were selected. RA acquisitions from a Toshiba Infinix-I system were postprocessed and printed with a Stratasys Eden 260. Two independent observers measured 5-10 points of interest on both the RA and the 3D model. Bland Altman plot was used to compare the measurements on rotational angiography to the printed model. Models were printed from RA in 5 patients (age 2 months-1 year). Diagnoses included (a) coronary artery aneurysm, (b) Glenn shunt, (c) coarctation of the aorta, (d) tetralogy of Fallot with MAPCAs, and (e) pulmonary artery stenosis. There was no significant measurement difference between RA and the printed model (r = 0.990, p < 0.01, Bland Altman p = 0.987). There was also no significant inter-observer variability. The MAPCAs model was referenced by the surgeon intraoperatively and was accurate. Rotational angiography can generate highly accurate 3D models in congenital heart disease, including in small vascular structures. These models can be extremely useful in patient evaluation and management.

3D-printing techniques in a medical setting: a systematic literature review

BACKGROUND

Three-dimensional (3D) printing has numerous applications and has gained much interest in the medical world. The constantly improving quality of 3D-printing applications has contributed to their increased use on patients. This paper summarizes the literature on surgical 3D-printing applications used on patients, with a focus on reported clinical and economic outcomes.

METHODS

Three major literature databases were screened for case series (more than three cases described in the same study) and trials of surgical applications of 3D printing in humans.

RESULTS

227 surgical papers were analyzed and summarized using an evidence table. The papers described the use of 3D printing for surgical guides, anatomical models, and custom implants. 3D printing is used in multiple surgical domains, such as orthopedics, maxillofacial surgery, cranial surgery, and spinal surgery. In general, the advantages of 3D-printed parts are said to include reduced surgical time, improved medical outcome, and decreased radiation exposure. The costs of printing and additional scans generally increase the overall cost of the procedure.

CONCLUSION

3D printing is well integrated in surgical practice and research. Applications vary from anatomical models mainly intended for surgical planning to surgical guides and implants. Our research suggests that there are several advantages to 3D-printed applications, but that further research is needed to determine whether the increased intervention costs can be balanced with the observable advantages of this new technology. There is a need for a formal cost-effectiveness analysis.