A patient-specific proof of concept with a 3D-printed model before performing an endovascular bentall procedure

Bone defects are extremely common in children with cleft-craniofacial conditions, especially those with alveolar cleft defects and cranial defects. This study used patient-specific 3D-printed molds derived from computed tomography and cryogel scaffold fabrication as a proof of concept for the creation of site-specific implants for bone reconstruction. Cryogel scaffolds are unique tissue-engineered constructs formed at sub-zero temperatures. When thawed, the resulting structure is macroporous, sponge-like, and mechanically durable. Due to these unique properties, cryogels have excellent potential for the treatment of patient-specific bone defects; however, there is little literature on their use in cleft-craniofacial defects. While 3D-printing technology currently lacks the spatial resolution to print the microstructure necessary for bone regeneration, it can be used to create site-specific molds. Thus, it is ideal to integrate these techniques for the fabrication of scaffolds with patient-specific geometry. Overall, all cryogels possessed appropriate geometry to allow for cell infiltration after 28 days. Additionally, suitable mechanical durability was demonstrated where, despite mold geometry, all cryogels could be compressed without exhibiting crack propagation. Such a patient-specific scaffold would be ideal in pediatric cleft-craniofacial defects, as these are complex 3D defects and children have less donor bone availability.

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Quality Control in 3D Printing: Accuracy Analysis of 3D-Printed Models of Patient-Specific Anatomy

Materials ◽

10.3390/ma14041021 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1021

Author(s):

Bernhard Dorweiler ◽

Pia Elisabeth Baqué ◽

Rayan Chaban ◽

Ahmed Ghazy ◽

Oroa Salem

Keyword(s):

Wall Thickness ◽

Large Scale ◽

Fused Deposition Modeling ◽

Vascular Anatomy ◽

3D Models ◽

Patient Specific ◽

Stl File ◽

Fused Deposition ◽

3D Printed ◽

The Mean

As comparative data on the precision of 3D-printed anatomical models are sparse, the aim of this study was to evaluate the accuracy of 3D-printed models of vascular anatomy generated by two commonly used printing technologies. Thirty-five 3D models of large (aortic, wall thickness of 2 mm, n = 30) and small (coronary, wall thickness of 1.25 mm, n = 5) vessels printed with fused deposition modeling (FDM) (rigid, n = 20) and PolyJet (flexible, n = 15) technology were subjected to high-resolution CT scans. From the resulting DICOM (Digital Imaging and Communications in Medicine) dataset, an STL file was generated and wall thickness as well as surface congruency were compared with the original STL file using dedicated 3D engineering software. The mean wall thickness for the large-scale aortic models was 2.11 µm (+5%), and 1.26 µm (+0.8%) for the coronary models, resulting in an overall mean wall thickness of +5% for all 35 3D models when compared to the original STL file. The mean surface deviation was found to be +120 µm for all models, with +100 µm for the aortic and +180 µm for the coronary 3D models, respectively. Both printing technologies were found to conform with the currently set standards of accuracy (<1 mm), demonstrating that accurate 3D models of large and small vessel anatomy can be generated by both FDM and PolyJet printing technology using rigid and flexible polymers.

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Total Meniscus Reconstruction Using a Polymeric Hybrid-Scaffold: Combined with 3D-Printed Biomimetic Framework and Micro-Particle

Polymers ◽

10.3390/polym13121910 ◽

2021 ◽

Vol 13 (12) ◽

pp. 1910

Author(s):

Hun-Jin Jeong ◽

Se-Won Lee ◽

Myoung Wha Hong ◽

Young Yul Kim ◽

Kyoung Duck Seo ◽

...

Keyword(s):

Shape Matching ◽

Femoral Condyle ◽

Immunohistochemical Analysis ◽

Cartilage Degeneration ◽

Patient Specific ◽

Hybrid Scaffold ◽

Meniscus Tissue ◽

Cell Source ◽

3D Printed ◽

Meniscus Regeneration

The meniscus has poor intrinsic regenerative capability, and its injury inevitably leads to articular cartilage degeneration. Although there are commercialized off-the-shelf alternatives to achieve total meniscus regeneration, each has its own shortcomings such as individualized size matching issues and inappropriate mechanical properties. We manufactured a polycaprolactone-based patient-specific designed framework via a Computed Tomography scan images and 3D-printing technique. Then, we completed the hybrid-scaffold by combining the 3D-printed framework and mixture micro-size composite which consists of polycaprolactone and sodium chloride to create a cell-friendly microenvironment. Based on this hybrid-scaffold with an autograft cell source (fibrochondrocyte), we assessed mechanical and histological results using the rabbit total meniscectomy model. At postoperative 12-week, hybrid-scaffold achieved neo-meniscus tissue formation, and its shape was maintained without rupture or break away from the knee joint. Histological and immunohistochemical analysis results showed obvious ingrowth of the fibroblast-like cells and chondrocyte cells as well as mature lacunae that were embedded in the extracellular matrix. Hybrid-scaffolding resulted in superior shape matching as compared to original meniscus tissue. Histological analysis showed evidence of extensive neo-meniscus cell ingrowth. Additionally, the hybrid-scaffold did not induce osteoarthritis on the femoral condyle surface. The 3D-printed hybrid-scaffold may provide a promising approach that can be applied to those who received total meniscal resection, using patient-specific design and autogenous cell source.

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Design, Fabrication, and Accuracy of a Novel Noncovering Lock-Mechanism Bilateral Patient-Specific Drill Guide Template for Nondeformed and Deformed Thoracic Spines

HSS Journal ® ◽

10.1177/1556331621996331 ◽

2021 ◽

pp. 155633162199633

Author(s):

Mehran Ashouri-Sanjani ◽

Shima Mohammadi-Moghadam ◽

Parisa Azimi ◽

Navid Arjmand

Keyword(s):

Thoracic Spine ◽

Sagittal Plane ◽

Ct Scanning ◽

Entry Point ◽

In Vivo Studies ◽

Patient Specific ◽

Plane Angle ◽

Severe Scoliosis ◽

3D Printed

Background: Pedicle screw (PS) placement has been widely used in fusion surgeries on the thoracic spine. Achieving cost-effective yet accurate placements through nonradiation techniques remains challenging. Questions/Purposes: Novel noncovering lock-mechanism bilateral vertebra-specific drill guides for PS placement were designed/fabricated, and their accuracy for both nondeformed and deformed thoracic spines was tested. Methods: One nondeformed and 1 severe scoliosis human thoracic spine underwent computed tomographic (CT) scanning, and 2 identical proportions of each were 3-dimensional (3D) printed. Pedicle-specific optimal (no perforation) drilling trajectories were determined on the CT images based on the entry point/orientation/diameter/length of each PS. Vertebra-specific templates were designed and 3D printed, assuring minimal yet firm contacts with the vertebrae through a noncovering lock mechanism. One model of each patient was drilled using the freehand and one using the template guides (96 pedicle drillings). Postoperative CT scans from the models with the inserted PSs were obtained and superimposed on the preoperative planned models to evaluate deviations of the PSs. Results: All templates fitted their corresponding vertebra during the simulated operations. As compared with the freehand approach, PS placement deviations from their preplanned positions were significantly reduced: for the nonscoliosis model, from 2.4 to 0.9 mm for the entry point, 5.0° to 3.3° for the transverse plane angle, 7.1° to 2.2° for the sagittal plane angle, and 8.5° to 4.1° for the 3D angle, improving the success rate from 71.7% to 93.5%. Conclusions: These guides are valuable, as the accurate PS trajectory could be customized preoperatively to match the patients’ unique anatomy. In vivo studies will be required to validate this approach.

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3D‐printed, patient‐specific intracranial aneurysm models: From clinical data to flow experiments with endovascular devices

Medical Physics ◽

10.1002/mp.14714 ◽

2021 ◽

Author(s):

Mariya S. Pravdivtseva ◽

Eva Peschke ◽

Thomas Lindner ◽

Fritz Wodarg ◽

Johannes Hensler ◽

...

Keyword(s):

Intracranial Aneurysm ◽

Clinical Data ◽

Patient Specific ◽

3D Printed ◽

Flow Experiments ◽

Endovascular Devices

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Custom, spray coated receive coils for magnetic resonance imaging

Scientific Reports ◽

10.1038/s41598-021-81833-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

A. M. Zamarayeva ◽

K. Gopalan ◽

J. R. Corea ◽

M. Z. Liu ◽

K. Pang ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Silver Nanoparticle ◽

Material Selection ◽

Spray Deposition ◽

Dielectric Materials ◽

Patient Specific ◽

High Signal ◽

Resonance Imaging ◽

3D Printed

AbstractWe have developed a process for fabricating patient specific Magnetic Resonance Imaging (MRI) Radio-frequency (RF) receive coil arrays using additive manufacturing. Our process involves spray deposition of silver nanoparticle inks and dielectric materials onto 3D printed substrates to form high-quality resonant circuits. In this paper, we describe the material selection and characterization, process optimization, and design and testing of a prototype 4-channel neck array for carotid imaging. We show that sprayed polystyrene can form a low loss dielectric layer in a parallel plate capacitor. We also demonstrate that by using sprayed silver nanoparticle ink as conductive traces, our devices are still dominated by sample noise, rather than material losses. These results are critical for maintaining high Signal-to-Noise-Ratio (SNR) in clinical settings. Finally, our prototype patient specific coil array exhibits higher SNR (5 × in the periphery, 1.4 × in the center) than a commercially available array designed to fit the majority of subjects when tested on our custom neck phantom. 3D printed substrates ensure an optimum fit to complex body parts, improve diagnostic image quality, and enable reproducible placement on subjects.

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Development of a 3D printed patient-specific neonatal brain simulation model using multimodality imaging for perioperative management

Pediatric Research ◽

10.1038/s41390-021-01421-w ◽

2021 ◽

Author(s):

Michael Wagner ◽

Tobias Werther ◽

Ewald Unger ◽

Gregor Kasprian ◽

Gregor Dovjak ◽

...

Keyword(s):

Simulation Model ◽

Perioperative Management ◽

Multimodality Imaging ◽

Patient Specific ◽

Neonatal Brain ◽

Brain Simulation ◽

3D Printed

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Preparation and Performance Evaluation of Duotone 3D-Printed Polyetheretherketone as Oral Prosthetic Materials: A Proof-of-Concept Study

Polymers ◽

10.3390/polym13121949 ◽

2021 ◽

Vol 13 (12) ◽

pp. 1949

Author(s):

Ling Ding ◽

Wei Lu ◽

Jiaqi Zhang ◽

Chuncheng Yang ◽

Guofeng Wu

Keyword(s):

Titanium Dioxide ◽

Performance Evaluation ◽

Mechanical Performance ◽

Mechanical Tests ◽

Flexural Properties ◽

Proof Of Concept ◽

Tooth Color ◽

Dental Application ◽

3D Printed ◽

And Performance

Literature has reported the successful use of 3D printed polyetheretherketone (PEEK) to fabricate human body implants and oral prostheses. However, the current 3D printed PEEK (brown color) cannot mimic the vivid color of oral tissues and thus cannot meet the esthetical need for dental application. Therefore, titanium dioxide (TiO2) and ferric oxide (Fe2O3) were incorporated into PEEK to prepare a series of tooth-color and gingival-color PEEK composites in this study. Through color measurements and mechanical tests, the color value and mechanical performance of the 3D printed PEEK composites were evaluated. In addition, duotone PEEK specimens were printed by a double nozzle with an interface between tooth-color and gingival-color parts. The mechanical performance of duotone PEEK with two different interfaces (horizontal and vertical) was investigated. With the addition of TiO2 and Fe2O3, the colors of 3D printed PEEK composites become closer to that of dental shade guides. 3D printed PEEK composites generally demonstrated superior tensile and flexural properties and hence have great potential in the dental application. In addition, duotone 3D printed PEEK with a horizontal interfacial orientation presented better mechanical performance than that with a vertical one.

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The Development of Novel 2-in-1 Patient-Specific, 3D-Printed Laminectomy Guides with Integrated Pedicle Screw Drill Guides

World Neurosurgery ◽

10.1016/j.wneu.2021.01.092 ◽

2021 ◽

Author(s):

Andrew Kanawati ◽

Renan Jose Rodrigues Fernandes ◽

Aaron Gee ◽

Jennifer Urquhart ◽

Fawaz Siddiqi ◽

...

Keyword(s):

Pedicle Screw ◽

Patient Specific ◽

3D Printed

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