3D-Printed Coronary Plaques to Simulate High Calcification in the Coronary Arteries for Investigation of Blooming Artifacts

The diagnostic value of coronary computed tomography angiography (CCTA) is significantly affected by high calcification in the coronary arteries owing to blooming artifacts limiting its accuracy in assessing the calcified plaques. This study aimed to simulate highly calcified plaques in 3D-printed coronary models. A combination of silicone + 32.8% calcium carbonate was found to produce 800 HU, representing extensive calcification. Six patient-specific coronary artery models were printed using the photosensitive polyurethane resin and a total of 22 calcified plaques with diameters ranging from 1 to 4 mm were inserted into different segments of these 3D-printed coronary models. The coronary models were scanned on a 192-slice CT scanner with 70 kV, pitch of 1.4, and slice thickness of 1 mm. Plaque attenuation was measured between 1100 and 1400 HU. Both maximum-intensity projection (MIP) and volume rendering (VR) images (wide and narrow window widths) were generated for measuring the diameters of these calcified plaques. An overestimation of plaque diameters was noticed on both MIP and VR images, with measurements on the MIP images close to those of the actual plaque sizes (<10% deviation), and a large measurement discrepancy observed on the VR images (up to 50% overestimation). This study proves the feasibility of simulating extensive calcification in coronary arteries using a 3D printing technique to develop calcified plaques and generate 3D-printed coronary models.

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Method to simulate distal flow resistance in coronary arteries in 3D printed patient specific coronary models

3D Printing in Medicine ◽

10.1186/s41205-020-00072-7 ◽

2020 ◽

Vol 6 (1) ◽

Cited By ~ 1

Author(s):

Kelsey N. Sommer ◽

Vijay Iyer ◽

Kanako Kunishima Kumamaru ◽

Ryan A. Rava ◽

Ciprian N. Ionita

Keyword(s):

Coronary Arteries ◽

Flow Resistance ◽

Patient Specific ◽

3D Printed ◽

Distal Flow

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Patient-Specific 3-Dimensional Printed Models for Planning Nasal Osteotomy to Correct Nasal Deformities Due to Trauma

OTO Open ◽

10.1177/2473974x20924342 ◽

2020 ◽

Vol 4 (2) ◽

pp. 2473974X2092434

Author(s):

Yong Gi Jung ◽

Hanaro Park ◽

Jiwon Seo

Keyword(s):

Fused Deposition Modeling ◽

Nasal Bone ◽

Patient Specific ◽

3 Dimensional ◽

Fused Deposition ◽

Computed Tomography Images ◽

Real Size ◽

Deposition Modeling ◽

3D Printed ◽

3D Printing Technique

Nasal deformities due to trauma are more challenging to correct with rhinoplasty than nasal deformities of nontraumatic causes. Nasal osteotomy is an essential procedure for bone deviations. Preoperative planning is vital in these cases, but it is challenging to comprehend 3-dimensional (3D) structures of the nasal bone on 2-dimensional facial photographs and computed tomography images. We used a 3D-printing technique to fabricate real-size facial bone models with similar physical properties and texture as the actual bone. Furthermore, we established a precise surgical plan using simulated osteotomy on the 3D-printed model. Fused deposition modeling–type desktop 3D printer with polylactic acid filaments was used. A surgical plan was established using simulated osteotomy in 11 cases, and the actual surgery was performed as planned in 10 cases (90.9%). The 3D-printed model and stimulated osteotomy were useful for precise planning of osteotomy to correct nasal deformities due to trauma.

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3D printing in modern cardiology

Current Pharmaceutical Design ◽

10.2174/1381612826666200622132440 ◽

2020 ◽

Vol 26 ◽

Cited By ~ 1

Author(s):

Simona Celi ◽

Emanuele Gasparotti ◽

Katia Capellini ◽

Emanuele Vignali ◽

Benigno Marco Fanni ◽

...

Keyword(s):

3D Printing ◽

Clinical Utility ◽

Surgical Planning ◽

Image Data ◽

Patient Specific ◽

Cardiovascular Medicine ◽

Printing Technique ◽

3D Printed ◽

Intervention Planning ◽

3D Printing Technique

Background: 3D printing represents an emerging technology in the field of cardiovascular medicine. 3D printing can help to perform a better analysis of complex anatomies to optimize intervention planning. Methods: A systematic review was performed to illustrate the 3D printing technology and to describe the workflow to obtain 3D printed models from patient-specific images. Examples from our laboratory of the benefit of 3D printing in planning interventions were also reported. Results: 3D printing technique is reliable when applied to high-quality 3D image data (CTA, CMR, 3D echography) but it still need the involvement of expert operators for image segmentation and mesh refinement. 3D printed models could be useful in interventional planning, although prospective studies with comprehensive and clinically meaningful endpoints are required to demonstrate the clinical utility. Conclusion: 3D printing can be used to improve anatomy understanding and surgical planning.

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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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