Point-of-care 3D printing: a low-cost approach to teaching carotid artery stenting

Abstract Background Carotid Artery Stenting (CAS) is increasingly being used in selected patients as a minimal invasive approach to carotid endarterectomy. Despite the long standing tradition of endovascular treatments, visual feedback during stent-deployment is impossible to obtain as deployment is performed under fluoroscopic imaging. Furthermore, the concept of stent-placement is often still unclear to patients. 3D Printing allows to replicate patient-specific anatomies and deploy stents inside them to simulate procedures. As such these models are being used for endovascular training as well as patient education. Purpose To our knowledge, this study reports the first use of a low-cost patient-specific 3D printed model for teaching CAS deployment under direct visualization, without fluoroscopy. Methodology A CT-angiogram was segmented and converted to STL format using Mimics inPrint™ software. The carotid arteries were bilaterally truncated to fit the whole model on a Formlabs 2 printer without omitting the internal vessel diameter. Next, this model was offset using a 1 mm margin. A ridge was modelled on the original vessel anatomy which was subsequently subtracted from the offset model in order to obtain a deroofed 3D model. All vessels were truncated to facilitate post-processing, flow and guide wire placement. Results Carotid artery stents were successfully deployed inside the vessel. The deroofing allows for clear visualization of the bottlenecks and characteristics of CAS deployment and positioning, including stent foreshortening, tapering and recoil. This low-cost 3D model provides visual insights in stent deployment and positioning, and can allow for patient-specific procedure planning. Conclusions The presented approach demonstrates the use of low-cost 3D Printed CAS models in teaching complex stent behavior as observed during deployment. Two main findings are illustrated. On one hand, the feasibility of low-cost in-hospital model production is shown. On the other hand, the teaching of CAS deployment bottlenecks at the carotid level without the need for fluoroscopic guidance, is illustrated. The observed stent characteristics as shown during deployment are difficult to assess in radiologic models. Furthermore, printing patient-specific 3D models preoperatively could possibly assist in accurate patient selection, preoperative planning, case-specific training and patient education.

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Point-of-Care 3D Printing: a Low-Cost Approach to Teaching Carotid Artery Stenting

10.21203/rs.3.rs-164067/v1 ◽

2021 ◽

Author(s):

Pieter De Backer ◽

Charlotte Allaeys ◽

Charlotte Debbaut ◽

Roel Beelen

Keyword(s):

3D Printing ◽

Carotid Artery ◽

Carotid Artery Stenting ◽

3D Model ◽

Point Of Care ◽

Low Cost ◽

Patient Specific ◽

Stent Deployment ◽

Invasive Approach ◽

Minimal Invasive Approach

Abstract Background Carotid Artery Stenting (CAS) is increasingly being used in selected patients as a minimal invasive approach to carotid endarterectomy. Despite the abundance of performed endovascular treatments, the concept of stent-placement is still unclear to many patients. Furthermore, visual feedback on stent-deployment is difficult to obtain as it is always performed under radiographic feedback. Three-Dimensional (3D) printing might tackle both challenges. A particular use case of Point-of-Care 3D Printing is the pretreatment printing of vascular anatomy in support of endovascular procedures. Purpose This study reports the first use of a low-cost patient-specific 3D printed model for CAS education to both experienced surgeons and patients. Methodology An angio computed tomography (CT) scan was segmented and converted to STL format using Mimics inPrint™ software. The carotid arteries were bilaterally truncated to fit the whole model on a Formlabs 2 printer without omitting the internal vessel diameter. Next, this model was offset using a 1 mm margin. A ridge was modelled on the original vessel anatomy which was subsequently subtracted from the offset model in order to obtain a deroofed 3D model. All vessels were truncated as to facilitate flow on the inside. Results Date-expired carotid artery stents were successfully deployed inside the vessel. The deroofing allows for clear visualization of the bottlenecks and characteristics of CAS deployment and positioning, including foreshortening and tapering of the stent. This low-cost 3D model provides insights in stent deployment and positioning, and allows for patient-specific procedure planning. Conclusion Printing patient-specific 3D models preoperatively could assist in accurate patient selection, a better preoperative planning and case-specific training. Furthermore, this 3D model also allows for better patient education and informed consent. However, more research is warranted to evaluate the added value of these models.

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Accessing 3D Printed Vascular Phantoms for Procedural Simulation

Frontiers in Surgery ◽

10.3389/fsurg.2020.626212 ◽

2021 ◽

Vol 7 ◽

Author(s):

Jasamine Coles-Black ◽

Damien Bolton ◽

Jason Chuen

Keyword(s):

3D Printing ◽

Endovascular Procedures ◽

Low Cost ◽

3D Models ◽

Routine Care ◽

Aortic Aneurysms ◽

Patient Specific ◽

Ct Angiogram ◽

Abdominal Aortic ◽

3D Printed

Introduction: 3D printed patient-specific vascular phantoms provide superior anatomical insights for simulating complex endovascular procedures. Currently, lack of exposure to the technology poses a barrier for adoption. We offer an accessible, low-cost guide to producing vascular anatomical models using routine CT angiography, open source software packages and a variety of 3D printing technologies.Methods: Although applicable to all vascular territories, we illustrate our methodology using Abdominal Aortic Aneurysms (AAAs) due to the strong interest in this area. CT aortograms acquired as part of routine care were converted to representative patient-specific 3D models, and then printed using a variety of 3D printing technologies to assess their material suitability as aortic phantoms. Depending on the technology, phantoms cost $20–$1,000 and were produced in 12–48 h. This technique was used to generate hollow 3D printed thoracoabdominal aortas visible under fluoroscopy.Results: 3D printed AAA phantoms were a valuable addition to standard CT angiogram reconstructions in the simulation of complex cases, such as short or very angulated necks, or for positioning fenestrations in juxtarenal aneurysms. Hollow flexible models were particularly useful for device selection and in planning of fenestrated EVAR. In addition, these models have demonstrated utility other settings, such as patient education and engagement, and trainee and anatomical education. Further study is required to establish a material with optimal cost, haptic and fluoroscopic fidelity.Conclusion: We share our experiences and methodology for developing inexpensive 3D printed vascular phantoms which despite material limitations, successfully mimic the procedural challenges encountered during live endovascular surgery. As the technology continues to improve, 3D printed vascular phantoms have the potential to disrupt how endovascular procedures are planned and taught.

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Affordable and Faster Transradial Prosthetic Socket Production Using Photogrammetry and 3D Printing

Electronics ◽

10.3390/electronics9091456 ◽

2020 ◽

Vol 9 (9) ◽

pp. 1456

Author(s):

Rifky Ismail ◽

Rilo Berdin Taqriban ◽

Mochammad Ariyanto ◽

Ali Tri Atmaja ◽

Sugiyanto ◽

...

Keyword(s):

3D Printing ◽

3D Model ◽

Low Cost ◽

Digital Camera ◽

Processing Method ◽

3D Printer ◽

Casting Method ◽

Conventional Casting ◽

Prosthetic Socket ◽

3D Printed

This study aims to invent a new, low-cost, and faster method of prosthetic socket fabrication, especially in Indonesia. In this paper, the photogrammetry with the 3D printing method is introduced as the new applicative way for transradial prosthetic making. Photogrammetry is used to retrieve a 3D model of the amputated hand stump using a digital camera. A digital camera is used for photogrammetry technique and the resulting 3D model is printed using a circular 3D printer with Polylactic acid (PLA) material. The conventional casting socket fabrication method was also conducted in this study as a comparison. Both prosthetic sockets were analyzed for usability, and sectional area conformities to determine the size deviation using the image processing method. This study concludes that the manufacturing of transradial prosthetic sockets incorporating the photogrammetry technique reduces the total man-hour production. Based on the results, it can be implied that the photogrammetry technique is a more efficient and economical method compared to the conventional casting method. The 3D printed socket resulting from the photogrammetry method has a 5–19% area deviation to the casting socket but it is still preferable and adjustable for the transradial amputee when applied to the stump of the remaining hand.

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In-Hospital 3D Printed Scaphoid Prosthesis Using Medical-Grade Polyetheretherketone (PEEK) Biomaterial

BioMed Research International ◽

10.1155/2021/1301028 ◽

2021 ◽

Vol 2021 ◽

pp. 1-7

Author(s):

Philipp Honigmann ◽

Neha Sharma ◽

Ralf Schumacher ◽

Jasmine Rueegg ◽

Mathias Haefeli ◽

...

Keyword(s):

3D Printing ◽

Point Of Care ◽

Low Cost ◽

Three Dimensional ◽

Patient Specific ◽

Fused Filament Fabrication ◽

Patient Specific Implants ◽

Surgical Guides ◽

3D Printed ◽

Medical Grade

Recently, three-dimensional (3D) printing has become increasingly popular in the medical sector for the production of anatomical biomodels, surgical guides, and prosthetics. With the availability of low-cost desktop 3D printers and affordable materials, the in-house or point-of-care manufacturing of biomodels and Class II medical devices has gained considerable attention in personalized medicine. Another projected development in medical 3D printing for personalized treatment is the in-house production of patient-specific implants (PSIs) for partial and total bone replacements made of medical-grade material such as polyetheretherketone (PEEK). We present the first in-hospital 3D printed scaphoid prosthesis using medical-grade PEEK with fused filament fabrication (FFF) 3D printing technology.

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3D Printing Improved Testicular Prostheses: Using Lattice Infill Structure to Modify Mechanical Properties

Frontiers in Surgery ◽

10.3389/fsurg.2021.626143 ◽

2021 ◽

Vol 8 ◽

Author(s):

Jacob Skewes ◽

Michael Y. Chen ◽

David Forrestal ◽

Nicholas J. Rukin ◽

Maria A. Woodruff

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

3D Model ◽

Patient Specific ◽

Shore Hardness ◽

Elastomeric Material ◽

Hardness Tests ◽

3D Printed ◽

Manufacturing Methods ◽

Materials Used

Patients often opt for implantation of testicular prostheses following orchidectomy for cancer or torsion. Recipients of testicular prostheses report issues regarding firmness, shape, size, and position, aspects of which relate to current limitations of silicone materials used and manufacturing methods for soft prostheses. We aim to create a 3D printable testicular prosthesis which mimics the natural shape and stiffness of a human testicle using a lattice infill structure. Porous testicular prostheses were engineered with relative densities from 0.1 to 0.9 using a repeating cubic unit cell lattice inside an anatomically accurate testicle 3D model. These models were printed using a multi-jetting process with an elastomeric material and compared with current market prostheses using shore hardness tests. Additionally, standard sized porous specimens were printed for compression testing to verify and match the stiffness to human testicle elastic modulus (E-modulus) values from literature. The resulting 3D printed testicular prosthesis of relative density between 0.3 and 0.4 successfully achieved a reduction of its bulk compressive E-modulus from 360 KPa to a human testicle at 28 Kpa. Additionally, this is the first study to quantitatively show that current commercial testicular prostheses are too firm compared to native tissue. 3D printing allows us to create metamaterials that match the properties of human tissue to create customisable patient specific prostheses. This method expands the use cases for existing biomaterials by tuning their properties and could be applied to other implants mimicking native tissues.

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Three-dimensional printing versus conventional machining in the creation of a meatal urethral dilator: a cost and mechanical strength analysis

10.21203/rs.2.21033/v1 ◽

2020 ◽

Author(s):

Michael Yue-Cheng Chen ◽

Jacob Skewes ◽

Ryan Daley ◽

Maria Ann Woodruff ◽

Nicholas John Rukin

Keyword(s):

3D Printing ◽

Low Cost ◽

Three Dimensional ◽

Patient Specific ◽

Strength Analysis ◽

3D Printer ◽

Fused Deposition ◽

3D Printed ◽

The Cost ◽

Conventional Machining

Abstract Background Three-dimensional (3D) printing is a promising technology in medicine. Low-cost 3D printing options are accessible but the limitations are often poorly understood. We aim to compare fused deposition modelling (FDM), the most common and low cost 3D printing technique, with selective laser sintering (SLS) and conventional machining techniques in manufacturing meatal urethral dilators which were recently removed from the Australian market.Methods A meatal urethral dilator was designed using computer-aided design (CAD). The dilator was 3D printed vertically orientated on a low cost FDM 3D printer in polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS). It was also 3D printed horizontally orientated in ABS on a high-end FDM 3D printer with soluble support material, as well as on a SLS 3D printer in medical nylon. The dilator was also machined in medical stainless steel using a lathe. All dilators were tested mechanically in a custom rig by hanging calibrated weights from the handle until the dilator snapped.Results The horizontally printed ABS dilator experienced failure at a greater load than the vertically printed PLA and ABS dilators respectively (503g vs 283g vs 163g, p < 0.001). The SLS nylon dilator did not fail but began to bend and deformed at around 5,000g of pressure. The steel dilator did not bend even at 10,000g of pressure. The cost per dilator is highest for the steel dilator if assuming a low quantity of five at 98 USD, but this decreases to 30 USD for a quantity of 1000. In contrast, the cost for the SLS dilator is 33 USD for a quantity of five but relatively unchanged at 27 for a quantity of 1000.Conclusions SLS and conventional machining created clinically functional meatal dilators but low-cost FDM printing could not. We suggest that at the current time 3D printing is not a replacement for conventional manufacturing techniques which are still the most reliable way to produce large quantities of parts with a simple geometry such as the meatal dilator. 3D printing is best used for patient-specific parts, prototyping or manufacturing complex parts that have additional functionality that cannot be achieved with conventional machining methods.

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3D Printing for Complex Cranial Surgery Education: Technical Overview and Preliminary Validation Study

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0040-1722719 ◽

2021 ◽

Author(s):

Christopher S Graffeo ◽

Avital Perry ◽

Lucas P Carlstrom ◽

Maria Peris-Celda ◽

Amy Alexander ◽

...

Keyword(s):

3D Printing ◽

Skull Base ◽

Low Cost ◽

Patient Specific ◽

Cross Sectional ◽

Case Examples ◽

Cranial Surgery ◽

Selection Accuracy ◽

Wide Range ◽

3D Printed

Abstract Background: 3D printing—also known as additive manufacturing—has a wide range of applications. Reproduction of low-cost, high-fidelity, disease- or patient-specific models presents a key developmental area in simulation and education research for complex cranial surgery. Methods: Using cadaveric dissections as source materials, skull base models were created, printed, and tested for educational value in teaching complex cranial approaches. In this pilot study, assessments were made on the value of 3D printed models demonstrating the retrosigmoid and posterior petrosectomy approaches. Models were assessed and tested in a small cohort of neurosurgery resident subjects (n = 3) using a series of 10 radiographic and 2 printed case examples, with efficacy determined via agreement survey and approach selection accuracy. Results: All subjects indicated agreement or strong agreement for all study endpoints that 3D printed models provided significant improvements in understanding of neuroanatomic relationships and principles of approach selection, as compared to 2D dissections or patient cross-sectional imaging alone. Models were not superior to in-person hands-on teaching. Mean approach selection accuracy was 90% ( ± 13%) for 10 imaging-based cases, or 92% ( ± 7%) overall. Trainees strongly agreed that approach decision-making was enhanced by adjunctive use of 3D models for both radiographic and printed cases. Conclusion: 3D printed models incorporating skull base approaches and/or pathologies provide a compelling addition to the complex cranial education armamentarium. Based on our preliminary analysis, 3D printed models offer substantial potential for pedagogical value as dissection guides, adjuncts to preoperative study and case preparation, or tools for approach selection training and evaluation.

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Microstructured Surface Plasmon Resonance Sensor Based on Inkjet 3D Printing Using Photocurable Resins with Tailored Refractive Index

Polymers ◽

10.3390/polym13152518 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2518

Author(s):

Nunzio Cennamo ◽

Lorena Saitta ◽

Claudio Tosto ◽

Francesco Arcadio ◽

Luigi Zeni ◽

...

Keyword(s):

Surface Plasmon Resonance ◽

3D Printing ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Optical Sensor ◽

Low Cost ◽

3D Print ◽

Spr Sensor ◽

Resonance Sensor ◽

3D Printed

In this work, a novel approach to realize a plasmonic sensor is presented. The proposed optical sensor device is designed, manufactured, and experimentally tested. Two photo-curable resins are used to 3D print a surface plasmon resonance (SPR) sensor. Both numerical and experimental analyses are presented in the paper. The numerical and experimental results confirm that the 3D printed SPR sensor presents performances, in term of figure of merit (FOM), very similar to other SPR sensors made using plastic optical fibers (POFs). For the 3D printed sensor, the measured FOM is 13.6 versus 13.4 for the SPR-POF configuration. The cost analysis shows that the 3D printed SPR sensor can be manufactured at low cost (∼15 €) that is competitive with traditional sensors. The approach presented here allows to realize an innovative SPR sensor showing low-cost, 3D-printing manufacturing free design and the feasibility to be integrated with other optical devices on the same plastic planar support, thus opening undisclosed future for the optical sensor systems.

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Hybrid Spine Simulator Prototype for X-ray Free Pedicle Screws Fixation Training

Applied Sciences ◽

10.3390/app11031038 ◽

2021 ◽

Vol 11 (3) ◽

pp. 1038

Author(s):

Sara Condino ◽

Giuseppe Turini ◽

Virginia Mamone ◽

Paolo Domenico Parchi ◽

Vincenzo Ferrari

Keyword(s):

Augmented Reality ◽

Low Cost ◽

Lumbar Vertebrae ◽

Pedicle Screws ◽

Simulation Software ◽

Patient Specific ◽

Innovative Strategy ◽

X Ray ◽

3D Printed ◽

Harmful Radiation

Simulation for surgical training is increasingly being considered a valuable addition to traditional teaching methods. 3D-printed physical simulators can be used for preoperative planning and rehearsal in spine surgery to improve surgical workflows and postoperative patient outcomes. This paper proposes an innovative strategy to build a hybrid simulation platform for training of pedicle screws fixation: the proposed method combines 3D-printed patient-specific spine models with augmented reality functionalities and virtual X-ray visualization, thus avoiding any exposure to harmful radiation during the simulation. Software functionalities are implemented by using a low-cost tracking strategy based on fiducial marker detection. Quantitative tests demonstrate the accuracy of the method to track the vertebral model and surgical tools, and to coherently visualize them in either the augmented reality or virtual fluoroscopic modalities. The obtained results encourage further research and clinical validation towards the use of the simulator as an effective tool for training in pedicle screws insertion in lumbar vertebrae.

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Algorithm to Reduce Leading and Lagging in Conformal Direct-Print

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4040730 ◽

2018 ◽

Vol 140 (10) ◽

Cited By ~ 2

Author(s):

Morteza Vatani ◽

Faez Alkadi ◽

Jae-Won Choi

Keyword(s):

Additive Manufacturing ◽

3D Printing ◽

3D Model ◽

Three Dimensional ◽

Motion Direction ◽

B Spline ◽

And Topology ◽

Printing System ◽

3D Printed ◽

Printed Patterns

A novel additive manufacturing algorithm was developed to increase the consistency of three-dimensional (3D) printed curvilinear or conformal patterns on freeform surfaces. The algorithm dynamically and locally compensates the nozzle location with respect to the pattern geometry, motion direction, and topology of the substrate to minimize lagging or leading during conformal printing. The printing algorithm was implemented in an existing 3D printing system that consists of an extrusion-based dispensing module and an XYZ-stage. A dispensing head is fixed on a Z-axis and moves vertically, while the substrate is installed on an XY-stage and moves in the x–y plane. The printing algorithm approximates the printed pattern using nonuniform rational B-spline (NURBS) curves translated directly from a 3D model. Results showed that the proposed printing algorithm increases the consistency in the width of the printed patterns. It is envisioned that the proposed algorithm can facilitate nonplanar 3D printing using common and commercially available Cartesian-type 3D printing systems.

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