Three-dimensional printed models in multidisciplinary planning of complex tracheal reconstruction

Creating Patient-Specific 3D-Printed Airway Models for Slide Tracheoplasty

This protocol describes the method for creating 3D-printed trachea models for use in high-fidelity simulation-based training and advanced surgical planning for pediatric patients undergoing slide tracheoplasty. The goal is to provide a template and methodology to allow for replicability and more widespread dissemination of these models to improve clinical training and patient care. Laryngoscope, 134:4409-4413, 2024.

Three-dimensional modelling and printing in anterior chest wall reconstruction and stabilisation

Anterior chest wall instability as a result of sternocostal non-union is a rare complication but can give rise to invalidating pain and cardiac arrhythmias. A woman in her 40s was referred to us with anterior chest wall pain and instability after a modified Ravitch procedure. Sternocostal pseudoarthrosis was seen for which multiple operations were performed which were complicated by low-grade infections. A patient-specific three-dimensional modelled and printed prostheses was used in an operation to both lift the sternum for pectus correction and to reconnect the sternum and the sternal costal junction to regain anterior chest wall stability.

Multidisciplinary Advanced Surgical Planning for Slide Tracheoplasty Using 3D-Printed Models

OBJECTIVE

The objective of this study was to develop and assess multidisciplinary advanced surgical planning (ASP) sessions using three dimensional (3D) printed models for cervicothoracic slide tracheoplasty (CST). We hypothesized that these sessions would improve surgeon confidence, streamline intraoperative planning, and highlight the utility of 3D modeling.

METHODS

3D-printed patient-specific trachea models were used in pre-operative ASP sessions consisting of a multidisciplinary case discussion and hands-on slide tracheoplasty simulation. Participants completed a survey rating realism, utility, impact on the final surgical plan, and pre- and post-session confidence. Statistical analysis was performed via Wilcoxon and Kruskal-Wallis tests.

RESULTS

Forty-eight surveys were collected across nine sessions and 27 different physicians. On a 5-point Likert scale, models were rated as "very realistic", "very useful" (both median of 4, IQR 3-4 and 4-5, respectively). Overall confidence increased by 1.4 points (+/- 0.7, p < 0.0001), with the largest change seen in those with minimal prior slide tracheoplasty experience (p = 0.005). Participants felt that the sessions "strongly" impacted their surgical plan or anticipated performance (median 4, IQR 4-5), regardless of training level or experience.

CONCLUSION

3D-printed patient-specific models were successfully implemented in ASP sessions for CST. Models were deemed very realistic and very useful by surgeons across multiple specialties and training levels. Surgical planning sessions also strongly impacted the final surgical plan and increased surgeon confidence for CST.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:3395-3401, 2024.

Application of 3D-Printed Model in the Cervical Spine Osteochondroma Surgery: A Case Report

A 73-year-old woman having a throat lump sensation and dysphagia for the past several months presented at our otorhinolaryngology outpatient clinic. A physical examination disclosed a protruding subepithelial mass over the right tonsil fossa. The mass was not tender and had no mucosal lesions or signs of active infection. Therefore, we arranged face and neck computed tomography scans, which reported a solitary osseous lesion over the anterior-right aspect of the C1-2 joint. Considering the rarity and unfamiliar anatomy of this disease, we built a 3D-printed model to assist with the surgical rehearsal of the procedure as well as with a preoperation discussion with the patient and her family. We arranged a combined Otolaryngology-Neurosurgery department approach after discussion with the neurosurgeon and successfully removed the lesion without sacrificing the overlying longus capitis muscle. The pathology examination revealed no evidence of malignancy. The final diagnosis was cervical spine solitary osteochondroma. The patient had a complete recovery of both oral cavity and normal swallowing function. No tumor recurred during the 3-year follow-up. On the basis of this case, in-house 3D-printing technology can offer a rapid, reliable model for an interdisciplinary team to use to enhance personalized presurgical planning, thus providing better patient engagement during hospitalization.

Simulated slide tracheoplasty for congenital tracheal stenosis using three-dimensional printed models

PURPOSE

The slide tracheoplasty (STP) is the standard treatment for severe congenital tracheal stenosis (CTS). Understanding the features of the tracheal stenosis in each case and choosing an appropriate incision design are very important for successfully executing the procedure. The present study aimed to evaluate the advantages of three-dimensional (3D) printed models of the trachea for improving CTS.

METHODS

Three-D tracheal models were created using computed tomography (CT) data from ten patients undergoing STP for CTS. Simulated surgery was performed using the hollow models after reinforcing with them with a coating of gum spray. Clinical outcomes, including patient survival, postoperative surgical interventions, and time required for STP, were compared with the corresponding values in the last ten patients before the introduction of 3D model simulations.

RESULTS

All ten patients for whom simulated surgery using a 3D tracheal model were conducted achieved good airway patency after their STP. The surgeons reported feeling that the 3D model simulations were highly effective although there was no significant difference in the clinical outcomes of the groups with or without simulated STP. The models were useful not only for surgical planning but also for sharing important information among the multidisciplinary team and the patients' family.

CONCLUSION

Our experience using 3D tracheal models demonstrated several features enabling improvement in the surgical treatment of CTS.

A Laboratory Model and Scope of Three Dimensional Printing in Pediatric Airway Surgery Practice for Developing Nations Like Nepal

Pediatric airway surgery, one of the complex procedures in otolaryngology, often demands a good surgical dexterity. To improve the surgical skills, a simulation laboratory can be a good option. Here we present a model of an airway surgery laboratory which is very minimalist and can be easily established in any hospital setup. Also, we discuss briefly on how a three dimensional (3D) model of an airway can be generated and printed from the digital imaging and communications in medicine (DICOM) CT imaging data of the patients along with the scope of 3D printing in airway surgery.

Novel airway-cartilage combined model for medialization laryngoplasty and laryngotracheal reconstruction surgery planning

BACKGROUND

The clinical outcomes of surgical treatments for vocal cord paralysis and tracheal stenosis, such as medialization laryngoplasty and laryngotracheal reconstruction, vary owing to the complex anatomy and physiology of the human upper airway. However, advances in three-dimensional (3D) simulation and printing ushered its use on an office-based workstation to aid in several surgical areas.

METHODS

The preoperation neck computed tomography image was loaded into the InVesalius 3.0 software for manual segmentation of airway and nearby important anatomic landmarks including hyoid bone, thyroid cartilage, and cricoid cartilage. The 3D model of the desired anatomy structure was manufactured and used for presurgical planning and rehearsal of the surgery.

RESULTS

We review cases of four patients: two cases of unilateral vocal palsy undergoing medialization laryngoplasty and two cases of tracheal stenosis patients who used the air-cartilage combined model.

CONCLUSION

Preoperation planning of the medialization thyroplasty could be more precise by prevision of the paralyzed vocal cord plane. Tracheal surgery could benefit from a preoperative design of segmented length. The novel airway-cartilage combined model offers new insight into vocal cord and trachea surgery.

Comparison of Slide Tracheoplasty Technique on Postoperative Anatomic Outcomes in Three-Dimensional Printed Models

OBJECTIVES/HYPOTHESIS

We hypothesized that the use of three-dimensional (3D) printed tracheal models to reproducibly simulate surgical technique variations in slide tracheoplasty would demonstrate the quantitative impact of surgical variables on postoperative tracheal dimensions.

STUDY DESIGN

Prospective analysis of three-dimensional printed surgical simulation models.

METHODS

Slide tracheoplasty was performed on 3D printed long segment tracheal stenosis models with combinations of tracheal transection incision angle (90°, 45° beveled superior to inferior, 45° beveled inferior to superior) and tracheal transection location relative to the stenosis (at midpoint, 2 mm each superior and inferior to midpoint). Postoperative computed tomography (CT) scans measured changes in tracheal length, volume, and cross-sectional area compared to controls. Statistical analysis was performed using one-way analysis of variance and unpaired two-tailed t-tests.

RESULTS

Slide tracheoplasty yielded 27 reconstructed tracheas. On average, slide tracheoplasty reduced total tracheal length by 36%. Beveled tracheal incisions yielded 9.5% longer final tracheas than straight transection incisions (P < .0001). Cross-sectional area at the stenosis midpoint increased from 9.0 mm² to 45 mm² but did not vary with technique (P > .05). Total tracheal luminal volume increased from 900 mm³ to 1378 mm³ overall and was largest with beveled incisions (P = .03). More material was discarded with straight incisions compared to beveled (89 mg vs. 19 mg, P < .0001).

CONCLUSIONS

Beveled tracheal transection incisions resulted in increased tracheal length, longer anastomotic segments, increased volume, and reduced tissue waste as compared to straight incisions. Offsetting the incision from the midpoint of stenosis did not significantly affect reconstructed tracheal morphology. Using 3D printed models for surgical simulation can be helpful for the quantitative study of the effect isolated surgical variables on technical outcomes.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

Three dimensional printed models of the airway for preoperative planning of open Laryngotracheal surgery in children: Surgeon's perception of utility

BACKGROUND

Preoperative planning of open laryngotracheal surgery is important for achieving good results. This study examines the surgeon's perception of the importance of using life size 3D printed models of the pediatric airway on surgical decision making.

METHODS

Life-size three-dimensional models of the upper airway were created based on CT images of children scheduled for laryngotracheal-reconstruction and cricotracheal resection with anastomosis. Five pediatric airway surgeons evaluated the three-dimensional models for determining the surgical approach, incision location and length, graft length, and need for single or double-stage surgery of seven children (median age 4.4 years, M:F ratio 4:3). They rated the importance of the three-dimensional model findings compared to the direct laryngoscopy videos and CT findings for each domain on a validated Likert scale of 1-5.

RESULTS

The mean rating for all domains was 3.6 ± 0.63 ("moderately important" to "very important"), and the median rating was 4 ("very important"). There was full agreement between raters for length of incision and length of graft. The between-rater agreement was 0.608 ("good") for surgical approach, 0.585 ("moderate") for incision location, and 0.429 ("moderate") for need for single- or two-stage surgery.

CONCLUSION

Patient-specific three-dimensional printed models of children's upper airways were scored by pediatric airway surgeons as being moderately to very important for preoperative planning of open laryngotracheal surgery. Large-scale, objective outcome studies are warranted to establish the reliability and efficiency of these models.

The role of 3D printing in pediatric airway obstruction: A systematic review

BACKGROUND

Tracheomalacia and tracheal stenosis are complicated, patient-specific diseases that require a multidisciplinary approach to diagnose and treat. Surgical interventions such as aortopexy, slide tracheoplasty, and stents potentially have high rates of morbidity. Given the emergence of three-dimensional (3D) printing as a versatile adjunct in managing complex pathology, there is a growing body of evidence that there is a strong role for 3D printing in both surgical planning and implant creation for pediatric airway obstruction.

METHODS

A structured PubMed.gov literature search was utilized, and a two-researcher systematic review was performed following the PRISMA criteria. The following search query was utilized: (((((3D printing) OR three-dimensional printing) OR 3D printed) OR three-dimensional printed) AND trachea) OR airway.

RESULTS

Over 23,000 publications were screened. Eight literature reviews and thirty-seven original papers met inclusion criteria. Of the thirty-seven original papers, eleven discussed 3D printing for surgical planning and twenty-six discussed 3D printing implants for interventions.

CONCLUSION

The reported application of 3D printing for management of pediatric airway obstruction is emerging with positive and broad applications. 3D printing for surgical planning not only improves pre-operative assessment of surgical approach and stent customization, but also helps facilitate patient/family education. 3D printing for custom implantable interventions is focused on bioresorbable external airway splints and biological grafts, with both animal studies and human case reports showing good results in improving symptoms.

Coordinated approach to spinal and tracheal reconstruction in a patient with morquio syndrome

Morquio syndrome (Mucopolysaccharidosis IVA) is an autosomal recessive lysosomal storage disease with manifestations ranging from mild to severe phenotype. Mechanical spinal cord injury and airway insufficiency are major causes of mortality. A 17-year-old male patient with severe Morquio syndrome presented with cervical and upper thoracic spinal stenosis with spinal cord myelopathy, and progressive severe tracheal stenosis. Coordinated care among otolaryngology, orthopedic surgery, neurosurgery, anesthesiology, cardiovascular surgery, radiology, and pulmonology teams facilitated the successful planning and execution of two major surgical interventions in rapid succession. This is the first description of a successful coordinated spine and airway repair in the literature.

3D printed modeling contributes to reconstruction of complex chest wall instability

Background

Three-dimensional printed models are increasingly used in many fields including medicine and surgery, but their use in the planning and execution of complex chest wall reconstruction has not been adequately described. In cases of non-union or prior attempts at chest wall reconstruction which have failed, there can be substantial deviations from expected chest wall anatomy. We report a novel technique for pre-operative planning and surgical execution of complex chest wall reconstruction, assisted by 3D printing. Our objective was to utilize 3-D volumetric modeling coupled with 3-D printing to produce patient-specific models for chest wall reconstruction in complex cases.

Methods

Soft tissue reconstruction 0.75 mm slice thickness computed tomography (CT) imaging data was loaded into medical CAD software for segmentation. Lung, muscle, foreign bodies, and bony structureswere separated due to the differences in density between them. The 3D volumetric mesh was then quality checked and stereolithography files (STL) were made which were able to be utilized by the 3D printer. The STL files were exported to a Objet 500 material jetting printer that utilized several UV light cured photopolymers.

Results

As an example case, we discuss a 55 year old male who underwent resuscitative thoracotomy. In the early post-operative period, he developed a pulmonary hernia in the 6th intercostal space, repaired with wire cerclage reapproximation of ribs. He developed a symptomatic mobile chest wall at the site of prior repair with additional concern for dissociated anterior cartilage. In preparation for operative repair, a 3D printed model was created, demonstrating fractured cartilage anteriorly as well a saw effect through the six and seventh ribs. An additional model was created using the normal ribs from the right side in mirror image reflection to quantify the degree and precise geometry of mal-alignment to the left chest. These models were then utilized to determine the operative approach via a thoracotomy incision to remove the cerclage wires, followed by parasternal incision, reduction and plating of the sternocostal non-union bursa Rib non-unions were plate stabilized. Repeat imaging in follow-up has demonstrated continued appropriate alignment and the patient reported improvement in his symptoms.

Conclusion

At present, the cost of 3-D printing remains substantial, but given the improved planning in complex cases, this cost may be recaptured in the reduction of operative time and improved outcomes with reduced re-operation rates. We believe that the early adoption of this technology by surgeons can help improve surgical quality and provide enhanced individualized patient care. These patient-specific models facilitate identification of features which are often not detected with standard 3-D reconstructed CT rendering. Centers should pursue the integration of 3-D printed models into their practice and active collaborations between surgeons and modeling experts should be sought at every available opportunity.

Feasibility and potential of three-dimensional printing in laryngotracheal stenosis

Background

The use of three-dimensional printing has been rapidly expanding over the last several decades. Virtual surgical three-dimensional simulation and planning has been shown to increase efficiency and accuracy in various clinical scenarios.

Objectives

To report the feasibility of three-dimensional printing in paediatric laryngotracheal stenosis and discuss potential applications of three-dimensional printed models in airway surgery.

Method

Retrospective case series in a tertiary care aerodigestive centre.

Results

Three-dimensional printing was undertaken in two cases of paediatric laryngotracheal stenosis. One patient with grade 4 subglottic stenosis with posterior glottic involvement underwent an extended partial cricotracheal reconstruction. Another patient with grade 4 tracheal stenosis underwent tracheal resection and end-to-end anastomosis. Models of both tracheas were printed using PolyJet technology from a Stratasys Connex2 printer.

Conclusion

It is feasible to demonstrate stenosis in three-dimensional printed models, allowing for patient-specific pre-operative surgical simulation. The models serve as an educational tool for patients’ understanding of the surgery, and for teaching residents and fellows.

Indirect management of full-thickness tracheal erosion in a complex pediatric patient

Prolonged tracheostomy dependence in pediatric patients can be associated with significant complications, including damage to the tracheal wall requiring reconstruction. We present a case of an 8 year-old female with full-thickness tracheal erosion secondary to the presence of a tracheostomy tube combined with a narrow thoracic inlet. A direct tracheal reconstruction was considered but eliminated due to the poor tissue quality of the trachea. Instead, a multi-disciplinary surgical team conceived of a novel indirect approach to manage the patient's tracheal defect. To our knowledge the use of indirect repair of a full-thickness tracheal defect has not been reported in the literature.