A 3D-printed airway model for optimal double-lumen tube: A case report

The purpose of this systematic review is to collate and analyse the current literature which examines clinical applications of 3D printing for renal disease, alongside cost and time duration factors associated with the printing process. A comprehensive search of the literature was performed across five different databases to identify studies that qualitatively and quantitatively assessed the value of 3D-printed kidney models for renal disease. Twenty-seven studies met the selection criteria for inclusion in the review. Twenty-five were original studies, and two were case reports. Of the 22 studies reporting a qualitative evaluation, the analysis of findings demonstrated the value of the 3D-printed models in areas of clinician and patient education, and pre-surgical simulation for complex cases of renal disease. Of five studies performing a quantitative analysis, the analysis of results displayed a high level of spatial and anatomical accuracy amongst models, with benefits including reducing estimated blood loss and risk of intra-operative complications. Fourteen studies evaluated manufacturing costs and time duration, with costs ranging from USD 1 to 1000 per model, and time duration ranging from 15 min to 9 days. This review shows that the use of customised 3D-printed models is valuable in the education of junior surgeons as well as the enhancement of operative skills for senior surgeons due to a superior visualisation of anatomical networks and pathologic morphology compared to volumetric imaging alone. Furthermore, 3D-printed kidney models may facilitate interdisciplinary communication and decision-making regarding the management of patients undergoing operative treatment for renal disease. It cannot be suggested that a more expensive material constitutes a higher level of user-satisfaction and model accuracy. However, higher costs in the manufacturing of the 3D-printed models reported, on average, a slightly shorter time duration for the 3D-printing process and total manufacturing time.

An 8-year-old girl, diagnosed with mid-aortic syndrome (MAS) at the age of 2 months and under antihypertensive therapy, presented with severe systemic hypertension (>200/120 mmHg). Computed tomography (CT) examination revealed aortic aneurysm between severe stenoses at pre- and infra-renal segments, and occlusion of principal splanchnic arteries with peripheral collateral revascularization. Based on CT imaging, preoperative three-dimensional (3D) anatomy was reconstructed to assess aortic dimensions and a dedicated in vitro planning platform was designed to investigate the feasibility of a stenting procedure under fluoroscopic guidance. The in vitro system was designed to incorporate a translucent flexible 3D-printed patient-specific model filled with saline. A covered 8-zig 45-mm-long Cheatham-Platinum (CP) stent and a bare 8-zig, 34-mm-long CP stent were implanted with partial overlap to treat the stenoses (global peak-to-peak pressure gradient > 60 mmHg), excluding the aneurysm and avoiding risk of renal arteries occlusion. Percutaneous procedure was successfully performed with no residual pressure gradient and exactly replicating the strategy tested in vitro. Also, as investigated on the 3D-printed model, additional angioplasty was feasible across the frames of the stent to improve bilateral renal flow. Postoperative systemic pressure significantly reduced (130/70 mmHg) as well as dosage of antihypertensive therapy. This is the first report demonstrating the use of a 3D-printed model to effectively plan percutaneous intervention in a complex pediatric MAS case: taking full advantage of the combined use of a patient-specific 3D model and a dedicated in vitro platform, feasibility of the stenting procedure was successfully tested during pre-procedural assessment. Hence, use of patient-specific 3D-printed models and in vitro dedicated platforms is encouraged to assist pre-procedural planning and personalize treatment, thus enhancing intervention success.

Use of three-dimensional (3D) printed models for preoperative planning, patient-specific surgical guides, and implants in orthopaedic surgery is a burgeoning technology. It has not been established if 3D-printed models for preoperative planning are associated with improved clinical outcomes or if they are cost-effective for hip surgeries including total hip arthroplasty (THA), periacetabular osteotomy (PAO), proximal femoral osteotomy (PFO), and/or hip fractures. The purpose of this study was to conduct a systematic search and literature review to determine if preoperative planning for hip surgery using 3D-printed models was associated with improved intra- and postoperative outcomes. Specific aims were to determine the (1) types of applications and studies conducted, (2) types of 3D printing/materials used, (3) specific outcomes evaluated, (4) efficacy of 3D printing in planning for hip surgery, and (5) limitations of current research. The authors searched Medline, Embase, Cochrane Database of Systematic Reviews, CINAHL, and PubMed from inception through July 2017. Original research publications were included if the primary purpose was to evaluate 3D-printed models' ability to assist with the planning of hip surgeries. Papers were excluded if they were reviews, abstracts, and not available in English, their models were not patient-specific, or their research did not evaluate surgery of the acetabulofemoral joint or pelvis. Of the 3,369 unique papers identified, 21 met inclusion criteria after full-text review. Among the included studies, six evaluated 3D printing in THA, seven in PAO/PFO, and eight in fracture repairs/reconstruction. The research included nine case reports, three case series, one retrospective uncontrolled study, six prospective uncontrolled studies, and two prospective controlled studies. 3D printed models resulted in: reduced intraoperative improvisation, operating room time, blood loss/transfusions, improved positioning of plates/screws/implants, clinical scores, measures of realignment, and functional status. Recent innovations in 3D printing are promising but unproven to improve clinical outcomes in hip surgeries due to limitations of published research. This may impact utilization and reimbursement of 3D-printed models in hip surgery. Studies of resource utilization, cost-effectiveness, and controlled trials with standardized methods and clinical outcomes of relevance are needed.

3D printing in adult cardiac and vascular surgery has been evaluated over the last 10 years, and all of the available literature reports benefits from the use of 3D models. In the present study, we analyzed the current applications of 3D printing for adult cardiovascular disease treated with surgical or catheter-based interventions, including the clinical medical simulation of physiological or pathology conducted with 3D printing in this field. A search of PubMed and MEDLINE databases were supplemented by searching through bibliographies of key articles. Thereafter, data on demographic, clinical scenarios and application, imaging modality, purposes of using with 3D printing, outcomes and follow-up were extracted. A total of 43 articles were deemed eligible and included. 296 patients (mean age: 65.4±14.2 years; male, 58.2%) received 3D printing for cardiac and vascular surgery or conditions [percutaneous left atrial appendage occlusion (LAAO), TAVR, mitral valve disease, aortic valve replacement, coronary artery abnormality, HOCM, aortic aneurysm and aortic dissection, Kommerell’s diverticulum, primary cardiac tumor and ventricular aneurysm]. Eight papers reported the utility of 3D printing in the medical simulator and training fields. Most studies were conducted starting in 2014. Twenty-six was case report. The major scenario used with 3D printing technology was LAAO (50.3%) and followed by TAVR (17.6%). CT and echocardiography were two main imaging techniques that were used to generate 3D-printed heart models. All studies showed that 3D-printed models were helpful for preoperative planning, orientation, and medical teaching. The important finding is that 3D printing provides a unique patient-specific method to assess complex anatomy and is helpful for intraoperative orientation, decision-making, creating functional models, and teaching adult cardiac and vascular surgery, including catheter-based heart surgery.

Usefulness of 3D Printing to Manage Complex Tracheal Stenosis.

BackgroundPeripheral pulmonary lesion (PPL) incidence is rising because of increasedchest imaging sensitivity and frequency. For PPLs suspicious for lungcancer, current clinical guidelines recommend tissue diagnosis. Radialendobronchial ultrasound (R-EBUS) is a bronchoscopic technique used for thispurpose. It has been observed that diagnostic yield is impacted by theability to accurately manipulate the radial probe. However, such skills canbe acquired, in part, from simulation training. Three-dimensional (3D)printing has been used to produce training simulators for standardbronchoscopy but has not been specifically used to develop similar tools forR-EBUS.ObjectiveWe report the development of a novel ultrasound-compatible, anatomicallyaccurate 3D-printed R-EBUS simulator and evaluation of its utility as atraining tool.MethodsComputed tomography images were used to develop 3D-printed airway models withultrasound-compatible PPLs of “low” and “high”technical difficulty. Twenty-one participants were allocated to two groupsmatched for prior R-EBUS experience. The intervention group received 15minutes to pretrain R-EBUS using a 3D-printed model, whereas thenonintervention group did not. Both groups then performed R-EBUS on3D-printed models and were evaluated using a specifically developedassessment tool.ResultsFor the “low-difficulty” model, the intervention group achieveda higher score (21.5 ± 2.02) than the noninterventiongroup (17.1 ± 5.7), reflecting 26% improvementin performance (P = 0.03). For the“high-difficulty” model, the intervention group scored20.2 ± 4.21 versus 13.3 ± 7.36,corresponding to 52% improvement in performance(P = 0.02). Participants derivedbenefit from pretraining with the 3D-printed model, regardless of priorexperience level.Conclusion3D-printing can be used to develop simulators for R-EBUS education. Trainingusing these models significantly improves procedural performance and iseffective in both novice and experienced trainees.

3D print model for surgical planning in a case of recurrent osteoblastic osteosarcoma of the left maxilla. A case report

Bilateral pure facet joint dislocation in thoracolumbar junction (T11–T12) without facet fracture using a 3D digital printing model for surgical planning: A case report

To the Editor, The double lumen tube (DLT) is the airway of choice to establish and maintain lung isolation. However, it can be challenging to secure the airway with a DLT in patients with a difficult airway because DLTs are larger, more rigid, and more difficult to place into the trachea than single lumen tubes. Recently, a high level of success was achieved using the GlideScope (GLS) to assist in positioning a single lumen tube (SLT) in situations where the airway was considered or proven to be difficult. The GLS has also been advanced for DLT placement in patients with difficult airways. In collaboration with Verathon Medical Canada ULC, we recently designed a new semi-rigid intubating stylet, the GlideRite DLT Stylet (GR-DLT-S) (Figure), which can be used for primary DLT intubation with the GLS. The GlideRite DLT Stylet (Verathon Medical Canada ULC, Burnaby, BC, Canada) is a reusable device which has been commercially available since March 2010 (In Canada, information on the device is available from CAREstream Medical Ltd., Langley, BC, Canada). We undertook a preliminary study to observe the efficiency of the GR-DLT-S for primary insertion of a DLT with the GLS in patients presenting a normal upper airway. After obtaining Research Ethics Board approval from our institution, 50 adult patients scheduled for thoracic surgery and requiring lung isolation were enrolled after written informed consent. Exclusion criteria included patients with anticipated difficult bag-mask ventilation of the lungs or anticipated difficult tracheal intubation according to the standard criteria, such as Mallampati class [ 3. Following application of routine monitors, pre-oxygenation, induction, and paralysis, tracheal intubation with the DLT was undertaken using both the GLS and the GR-DLT-S. Forty-nine (98%) patients received tracheal intubation using the combination of DLT/GLS/GR-DLT-S. The mean time required for intubation was 46.3 (32.3) sec. The number of attempts was one in 37 patients (74%), two in 11 patients (22%), and three in one patient (2%). None of the subjects experienced complications associated with DLT insertion. Three publications have described the use of the Glidescope to facilitate DLT tracheal intubation. In 2005, Hernandez et al. described the first use of the GLS to introduce a DLT. In 2008, Chen et al. described a failure to insert a DLT with the GLS. They used the GLS to introduce a SLT, and afterwards, they used a tube exchanger to replace the SLT with a DLT, also with the assistance of the GLS. Finally, Bustamante et al. described a case report where bending the malleable stylet and sequential rotation of the DLT enabled them to introduce the DLT successfully. These authors reported a dozen successful cases using this technique. Over the past five years, we had several cases where we failed to intubate the trachea with a DLT using a similar method. The failed cases involved patients with little room to maneuver the DLT due to a large tongue or a small mouth opening. In these cases, the malleable stylet was not sufficiently rigid to maintain the optimal tube curvature. Since the introduction of the GR-DLT-S, tracheal intubation with the DLT has been successful using this new device in more than 15 patients with either a proven or an anticipated difficult airway. In conclusion, based on our initial experience, we suggest that the GR-DLT-S is effective when used in J. S. Bussieres, MD (&) F. Martel, MD J. Somma, MD S. Morin, MSc N. Gagne, PhD RRT Institut Universitaire de Cardiologie et de Pneumologie de Quebec, Quebec City, QC, Canada e-mail: jean.bussieres@anr.ulaval.ca

Background and Objectives Flexible fiberscopy is essential in the examination of the nose to larynx airway. However, the instrument is sensitive to manipulation and can sometimes be damaged when excessive external force is applied. In addition, patients can be injured during fiberscopic examination. In this regard, a airway model mimicking the human airway passage was developed for the education of fiberscopy to minimize the danger to both patient and fiberscope. Materials and Method Neck CT data was used to 3D-print the airway model. Using the 3D doctor software, the outlines of the air-filled cavities were extracted. The outline data was modified to make the inside of the outline empty and the outside filled with 3D ink resin. The airway data was used to 3D-print the replica in three pieces, which were then assembled into one. Flexible laryngoscopic examination of nose to larynx was performed using the nose-to-larynx airway model, and for a male patient enrolled in the study. Virtual endoscopy was performed using the same CT data. The examination data were then compared frame by frame with regards to the shapes and positions of nasal inlet, inferior turbinate, torus tubarius, hypopharynx, epiglottis and vocal cord. Results The airway model was very similar in shape and position of the anatomic landmarks compared with real human airway examined by the fiberscope. Conclusion The results of 3D-printed airway model showed similar shapes as the real human airway, and real time endoscopy could be done using the model. This technique can be extended to make models of tubed organs such as the intestine or the bronchial tree. Key words: Airway model ㆍ Fiberscope ㆍ 3D printer

A 31-year-old patient presented with an encapsulated sciatic nerve secondary to extensive hip heterotopic ossification (HO), which prevented visualization of a safe osteotomy site to avoid nerve damage. The 3D-printed model demonstrated an easily identifiable osseous reference point along the inferior aspect of the heterotopic mass, allowing for a vertical osteotomy to be safely performed. HO is associated with loss of normal anatomic topography. The current case report illustrates the use of a 3D-printed model to identify pertinent anatomic landmarks required for safe decompression of an encapsulated sciatic nerve within the anatomic region of the hip.

Sir, We thank the authors for the interest shown in our article[1] and for sharing information about computed tomography-derived volume-rendered virtual dissection.[2] The cost incurred in creating the virtual model (our case report) is indeed due to the technical expertise and the software required. As with all such technologies, we anticipate not only a steep fall in prices but also improvement in the quality of software and wider availability. We note that the model obtained by virtual dissection is computationally more complex and seems to suffer from similar shortfalls of the three-dimensional (3D) print software-derived virtual model. We would like to clarify any number, and a variety of cuts can easily be obtained on the virtual model. Further, baffles or other implants can be “added on” to the virtual model for improved surgical planning. Finally, the virtual model can always be processed to the logical next step – 3D-printed model which has indisputable advantages. A printed or virtual surface-rendered model by 3D printing software offers a more robust technique with solid algorithms to create a true 3D image which we feel is definitely more trustworthy, at least till larger comparative studies are conducted, for clinical and surgical decision-making. We feel that it is early to commit surgical or palliative line of treatment based on virtual dissection as elaborated by Dr. Gupta et al. We predict that the future will see merging of both technologies to create ideal virtual as well as 3D printable heart models. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

Introduction:Developmental dysplasia of hip (DDH) is abnormal development of hip joint causing mild subluxation to complete dislocation of femoral head from acetabulum. Incidence in India is 1–9.2/1000 . Typical risk factors for DDH are said to be female child, first born, breech position, positive family history, left hip, and unilateral involvement. Femoral head and acetabular compressive forces are mutually important stimulators for normal growth (both shape and depth). Deviation from above normal process due to subluxated or dislocated head since birth can lead to abnormal development of both acetabulum and femoral head. Diagnosis of the DDH is made at birth using clinical test and radiologically using ultrasound of hip joint. Management is based on the age of presentation and severity of the instability. Most hips are managed conservatively management depends on the age and symptoms of the patient.Case Report:A 14-year-old female child presented with the complaints of pain in the left hip and difficulty in walking. On clinical and radiological examination, she was diagnosed to have developmental dysplasia of the left hip with partial subluxation of the left hip. Thorough investigation and planning were done using CT PBH and 3D reconstruction of the pelvis to plan the osteotomy. Stages surgery was planned, first, triple innominate osteotomy was performed and later femoral varus derotation osteotomy 6 weeks later. At 3-year follow-up, the patient is pain free and is having no difficulty in doing day-to-day activities. X-ray showing complete coverage of the femoral head with no changes of arthritis in hip.Conclusion:Late presentations of neglected developmental dysplasia poses difficult challenges in management. It can be addressed with osteotomies for improving range of motion and preventing future early arthritis. In our case, good functional range of motion was restored at 3 years follow-up.

3D-printed airway model as a platform for SARS-CoV-2 infection and antiviral drug testing

Vocal cord paralysis is one of the most serious anesthetic complications related to endotracheal intubation. The practitioner should take extreme care, as bilateral vocal cord paralysis can obstruct the airway and lead to disastrous respiratory problems. There have been many papers on bilateral vocal cord paralysis after neck surgery, but reports on such a condition after lung surgery are very rare. We report a case of bilateral vocal cord paralysis detected after removal of a double-lumen endotracheal tube in a 67-year-old patient who underwent wedge resection by video-assisted thoracoscopic surgery. We also note that he recovered spontaneously without complications within a day.