3D-Printed Visceral Aneurysm Models Based on CT Data for Simulations of Endovascular Embolization: Evaluation of Size and Shape Accuracy

3D-printed patient-specific models provide added value for initial clinical diagnosis, preoperative surgical and implant planning and patient and trainee education. 3D spine models are usually designed using CT data, due to the ability to rapidly image osseous structures with high spatial resolution. Combining CT and MRI to derive a composite model of bony and neurological anatomy can potentially provide even more useful information for complex cases. We describe such a case involving an adolescent with a grade V spondylolisthesis in which a composite model was manufactured for preoperative and intraoperative evaluation and guidance. We provide a detailed workflow for creating such models and outline their potential benefit in guiding a multidisciplinary team approach.

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Impact of processing parameters and post-treatment on the shape accuracy of 3D-printed baking dough

International Journal of Food Science & Technology ◽

10.1111/ijfs.13904 ◽

2018 ◽

Vol 54 (1) ◽

pp. 68-74 ◽

Cited By ~ 13

Author(s):

Fan Yang ◽

Min Zhang ◽

Zhongxiang Fang ◽

Yaping Liu

Keyword(s):

Processing Parameters ◽

Post Treatment ◽

Shape Accuracy ◽

3D Printed

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Generic design of an anatomical heart model optimized for additive manufacturing with silicone

Rapid Prototyping Journal ◽

10.1108/rpj-11-2019-0283 ◽

2020 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Hannah Riedle ◽

Ahmed Ghazy ◽

Anna Seufert ◽

Vera Seitz ◽

Bernhard Dorweiler ◽

...

Keyword(s):

Surgical Simulation ◽

Patient Specific ◽

Heart Model ◽

Single Model ◽

Content Type ◽

Anatomical Features ◽

3D Printed ◽

Ct Data ◽

Silicone Model ◽

Generic Design

Purpose The purpose of this study is the generation of a thorough generic heart model optimized for direct 3D printing with silicone elastomers. Design/methodology/approach The base of the model design is segmentation of CT data, followed by a generic adaption and a constructive enhancement. The model is 3D printed with silicone. An evaluation of the physical model gives indications about its benefits and weaknesses. Findings The results show the feasibility of a generic design while maintaining anatomical correctness and the benefit of the generic approach to quickly derive a multiplicity of healthy and pathological versions from one single model. The material properties of the silicone model are sufficient for simulation, but the results of the evaluation indicate possible improvements, as for most anatomical features, the used silicone is too hard and too stretchable. Originality/value Previous developments mostly focus on patient-specific heart models. In contrast, this study sets out to explore the possibility and benefits of a generic approach. Standardized validated models would allow comparability in surgical simulation.

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Individualized Ophthalmic Exoplants by Means of Reverse Engineering and 3D Printing Technologies for Treating High Myopia Complications with Macular Buckles

Biomimetics ◽

10.3390/biomimetics5040054 ◽

2020 ◽

Vol 5 (4) ◽

pp. 54

Author(s):

George Pappas ◽

Nectarios Vidakis ◽

Markos Petousis ◽

Athena Maniadi

Keyword(s):

High Myopia ◽

Surgical Intervention ◽

Polymer Materials ◽

Eye Disease ◽

Pattern Recognition Techniques ◽

Surgical Methods ◽

3D Geometry ◽

Myopic Traction Maculopathy ◽

3D Printed ◽

Ct Data

Myopic macular foveoschisis maculopathy is an eye disease that is treated, in most cases, with surgical intervention, in which a macular buckle is applied to restore eye anatomy and functionality. A macular buckle is a type of exoplant that comes in various designs and sizes. Often, they are difficult to apply or they do not fit properly in the eye geometry since they have a generic form. In this work, the effort to develop the most suitable tailor-made macular buckle for each individual patient for treating myopic traction maculopathy is studied. Pattern recognition techniques are applied to the patient’s Computed Tomography (CT) data to develop the exact 3D geometry of the eye. Using this 3D geometry, the trajectory of the buckle is fitted and the buckle is formed, which is then 3D-printed with biocompatible polymer materials. It is expected that the power of technology will be used to activate the most precise approach for each individual patient. Considering the possible complications and technical difficulties of other surgical methods, the customized macular buckle is an appropriate, easy-to-use, and most precise piece of medical equipment for the treatment of myopic traction maculopathy.

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Efficiently registering scan point clouds of 3D printed parts for shape accuracy assessment and modeling

Journal of Manufacturing Systems ◽

10.1016/j.jmsy.2020.04.001 ◽

2020 ◽

Vol 56 ◽

pp. 587-597 ◽

Cited By ~ 2

Author(s):

Nathan Decker ◽

Yuanxiang Wang ◽

Qiang Huang

Keyword(s):

Accuracy Assessment ◽

Point Clouds ◽

Shape Accuracy ◽

3D Printed

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Three-Dimensional-Printed Model-Assisted Management of Craniovertebral Junction Abnormalities: An Institutional Experience with Literature Review

Asian Spine Journal ◽

10.31616/asj.2019.0138 ◽

2020 ◽

Vol 14 (2) ◽

pp. 204-211 ◽

Cited By ~ 1

Author(s):

Prashant Agarwal ◽

Sanjeev Chopra ◽

Virendra Deo Sinha ◽

Rashim Kataria

Keyword(s):

Vertebral Artery ◽

Three Dimensional ◽

3D Models ◽

Craniovertebral Junction ◽

Japanese Orthopedic Association ◽

Management Protocol ◽

Irreducible Atlantoaxial Dislocation ◽

3D Printed ◽

Ct Data ◽

Assisted Management

Study Design: Prospective study.Purpose: To evaluate the utility and limitations of using three-dimensional (3D)-printed models for the management of craniovertebral (CV) junction abnormalities.Overview of Literature: In comparison to other bony and vascular anomalies, CV junction abnormalities are difficult to treat. For cases of irreducible atlantoaxial dislocation (AAD), posterior reduction and stabilization have replaced anterior decompression as the standard management protocol. The use of 3D models, such as those described herein, can provide surgeons with in-depth knowledge of the vertebral artery course and bony anomalies associated with CV junction abnormalities.Methods: Clinical and radiological features of 18 patients with CV junction abnormalities were analyzed between March 2017 and February 2019 at Sawai Man Singh Medical College, Jaipur, India. Dynamic computed tomography (CT) of the CV junction and CT angiographies of the neck with respect to the vertebral artery course at the C1–C2 joints were obtained and studied. Customized 3D models of the CV junction were then made based on the CT data, and rehearsal of the surgical procedure was performed using the 3D model one day prior to performing the actual procedure.Results: Seventeen patients had congenital-type AAD, whereas one patient had posttraumatic AAD. Improvements in neck pain and myelopathy were seen in all patients at the follow-up, as analyzed using the Visual Analog Scale and the Japanese Orthopedic Association Scale score, respectively. There were no cases of malpositioning of screws or any direct vertebral artery injury, although in one patient, the distal flow in the dominant vertebral artery was cut off as it got compressed between the bony arch and the screw head.Conclusions: Compared to computer-generated images, 3D-printed models are a more practical approach for dealing with complex CV junction abnormalities. They provide surgeons with deep insights into the complex bony anomalies as well as variations in the vertebral artery courses, thereby improving surgical outcomes.

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3D-printed moulds facilitate making an anatomically matched cement spacer for reconstruction long bone defection after resection of tumors of humerous

Nepalese Journal of Cancer ◽

10.3126/njc.v2i1.25647 ◽

2018 ◽

Vol 2 (1) ◽

pp. 27-31

Author(s):

Haltao Zhao ◽

Arun Sigdel ◽

Xizhi Hou ◽

Ting Zhang ◽

Guochuan Zhang ◽

...

Keyword(s):

Proximal Humerus ◽

Tumor Resection ◽

Mirror Image ◽

Long Bone ◽

Wide Resection ◽

Cement Spacer ◽

3D Printed ◽

Ct Data ◽

Neo Adjuvant Chemotherapy ◽

The Right

Background: A nail and cement spacer is one of the option for the reconstruction of the proximal humerus after tumor resection among prosthesis unaffordable patients. However, making the cement spacer anatomically match its replacement remains challenging. Presentation of case: A 12-year-old boy was diagnosed with osteosarcoma in the right proximal humerus by core needle biopsy. After preoperative neo-adjuvant chemotherapy, a wide resection was performed, and the defect was reconstructed with an anatomically matched cement spacer. The cement spacer was fabricated using 3D-printed moulds, which were made according to the mirror image of the left humerus based on CT data. The post-operative course was uneventful, and at the 12-month follow-up, the patient is able to move with only some restriction in abduction and upward lift. The MSTD score was 21. Conclusion: Fabrication of an anatomically matched cement spacer using 3D-printed moulds is a simple, inexpensive, and reproducible procedure for reconstruction complex bone defect.

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Effects of Printing Parameters on the Fit of Implant-Supported 3D Printing Resin Prosthetics

Materials ◽

10.3390/ma12162533 ◽

2019 ◽

Vol 12 (16) ◽

pp. 2533 ◽

Cited By ~ 10

Author(s):

Gang-Seok Park ◽

Seong-Kyun Kim ◽

Seong-Joo Heo ◽

Jai-Young Koak ◽

Deog-Gyu Seo

Keyword(s):

3D Printing ◽

Layer Thickness ◽

Micro Ct ◽

Marginal Fit ◽

Dental Model ◽

Marginal Discrepancy ◽

3D Printed ◽

Ct Data ◽

Internal Gap ◽

Printing Parameters

The purpose of the study was to investigate the influence of 3D printing parameters on fit and internal gap of 3D printed resin dental prosthesis. The dental model was simulated and fabricated for three-unit prostheses with two implants. One hundred prostheses were 3D printed with two-layer thicknesses for five build orientations using a resin (NextDent C&B; 3D systems, Soesterberg, The Netherlands) and ten prostheses were manufactured with a milling resin as control. The prostheses were seated and scanned with micro-CT (computerized tomography). Internal gap volume (IGV) was calculated from 3D reconstructed micro-CT data. IGV, marginal fit, and lengths of internal gaps were measured, and the values were analyzed statistically. For the 3D printed prostheses, IGV was smaller at 45°, 60°, and 90° compared to other build orientations. The marginal fit evaluated by absolute marginal discrepancy was smaller than other build orientations at 45° and 60°. IGV was smaller at 50 µm layer thickness than at 100 µm layer thickness, but the marginal fit was smaller at 100 µm layer thickness than at 50 µm layer thickness. The 3D printed prosthesis had smaller internal gap than the milled prosthesis. The marginal fit of the 3D printed resin prosthesis was clinically acceptable, and build orientation of 45° and 60° would be recommended when considering fit and internal gap.

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Practicable assessment of cochlear size and shape from clinical CT images

Scientific Reports ◽

10.1038/s41598-021-83059-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Andrew H. Gee ◽

Yufeng Zhao ◽

Graham M. Treece ◽

Manohar L. Bance

Keyword(s):

Gold Standard ◽

Ct Images ◽

Statistical Shape Model ◽

Ct Scans ◽

Micro Ct ◽

Convenience Sample ◽

Size And Shape ◽

Statistical Shape ◽

Affine Deformation ◽

Ct Data

AbstractThere is considerable interpersonal variation in the size and shape of the human cochlea, with evident consequences for cochlear implantation. The ability to characterize a specific cochlea, from preoperative computed tomography (CT) images, would allow the clinician to personalize the choice of electrode, surgical approach and postoperative programming. In this study, we present a fast, practicable and freely available method for estimating cochlear size and shape from clinical CT. The approach taken is to fit a template surface to the CT data, using either a statistical shape model or a locally affine deformation (LAD). After fitting, we measure cochlear size, duct length and a novel measure of basal turn non-planarity, which we suggest might correlate with the risk of insertion trauma. Gold-standard measurements from a convenience sample of 18 micro-CT scans are compared with the same quantities estimated from low-resolution, noisy, pseudo-clinical data synthesized from the same micro-CT scans. The best results were obtained using the LAD method, with an expected error of 8–17% of the gold-standard sample range for non-planarity, cochlear size and duct length.

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