The advancement of technology and digitization has made reproductions of art omnipresent. However, 3D printing stands apart from previous and current reproduction methods due to its unique ability... Show moreThe advancement of technology and digitization has made reproductions of art omnipresent. However, 3D printing stands apart from previous and current reproduction methods due to its unique ability to accurately replicate all material characteristics of a painting, such as three-dimensionality, translucency, and glossiness, at a high level of detail. Additionally, its digital nature enables limitless possibilities for adding, modifying, and manipulating new or existing data. Indistinguishable Likeness investigates how the original and its 3D-printed twin disrupt the Western emphasis on the materially unique artwork. Utilizing an interdisciplinary approach, this dissertation integrates technical art history, 3D printing, contemporary museum and conservation studies, philosophy, cognitive psychology, neuroscience, and ethics to achieve a profound understanding of this technology. Applied to several case studies, the research demonstrates how 3D-printed reproductions provide new perspectives on original artworks, deepening our understanding of art history, conservation methods, and public engagement with art. Show less
OBJECTIVES: In complex double outlet right ventricle (DORV) patients, the optimal surgical approach may be difficult to assess based on conventional 2-dimensional (2D) ultrasound (US) and computed... Show moreOBJECTIVES: In complex double outlet right ventricle (DORV) patients, the optimal surgical approach may be difficult to assess based on conventional 2-dimensional (2D) ultrasound (US) and computed tomography (CT) imaging. The aim of this study is to assess the added value of 3-dimensional (3D) printed and 3D virtual reality (3D-VR) models of the heart used for surgical planning in DORV patients, supplementary to the gold standard 2D imaging modalities.METHODS: Five patients with different DORV subtypes and high-quality CT scans were selected retrospectively. 3D prints and 3D-VR models were created. Twelve congenital cardiac surgeons and paediatric cardiologists, from 3 different hospitals, were shown 2D-CT first, after which they assessed the 3D print and 3D-VR models in random order. After each imaging method, a questionnaire was filled in on the visibility of essential structures and the surgical plan.RESULTS: Spatial relationships were generally better visualized using 3D methods (3D printing/3D-VR) than in 2D. The feasibility of ventricular septum defect patch closure could be determined best using 3D-VR reconstructions (3D-VR 92%, 3D print 66% and US/CT 46%, P < 0.01). The percentage of proposed surgical plans corresponding to the performed surgical approach was 66% for plans based on US/CT, 78% for plans based on 3D printing and 80% for plans based on 3D-VR visualization.CONCLUSIONS: This study shows that both 3D printing and 3D-VR have additional value for cardiac surgeons and cardiologists over 2D imaging, because of better visualization of spatial relationships. As a result, the proposed surgical plans based on the 3D visualizations matched the actual performed surgery to a greater extent. Show less
Background: Accuracy and precision assessment in radiomic features is important for the determination of their potential to characterize cancer lesions. In this regard, simulation of different... Show moreBackground: Accuracy and precision assessment in radiomic features is important for the determination of their potential to characterize cancer lesions. In this regard, simulation of different imaging conditions using specialized phantoms is increasingly being investigated. In this study, the design and evaluation of a modular multimodality imaging phantom to simulate heterogeneous uptake and enhancement patterns for radiomics quantification in hybrid imaging is presented. Methods: A modular multimodality imaging phantom was constructed that could simulate different patterns of heterogeneous uptake and enhancement patterns in positron emission tomography (PET), single-photon emission computed tomography (SPECT), computed tomography (CT), and magnetic resonance (MR) imaging. The phantom was designed to be used as an insert in the standard NEMA-NU2 IEC body phantom casing. The entire phantom insert is composed of three segments, each containing three separately fillable compartments. The fillable compartments between segments had different sizes in order to simulate heterogeneous patterns at different spatial scales. The compartments were separately filled with different ratios of Tc-99m-pertechnetate, F-18-fluorodeoxyglucose ([F-18]FDG), iodine- and gadolinium-based contrast agents for SPECT, PET, CT, and T-1-weighted MR imaging respectively. Image acquisition was performed using standard oncological protocols on all modalities and repeated five times for repeatability assessment. A total of 93 radiomic features were calculated. Variability was assessed by determining the coefficient of quartile variation (CQV) of the features. Comparison of feature repeatability at different modalities and spatial scales was performed using Kruskal-Wallis-, Mann-Whitney U-, one-way ANOVA- and independent t-tests. Results: Heterogeneous uptake and enhancement could be simulated on all four imaging modalities. Radiomic features in SPECT were significantly less stable than in all other modalities. Features in PET were significantly less stable than in MR and CT. A total of 20 features, particularly in the gray-level co-occurrence matrix (GLCM) and gray-level run-length matrix (GLRLM) class, were found to be relatively stable in all four modalities for all three spatial scales of heterogeneous patterns (with CQV < 10%). Conclusion: The phantom was suitable for simulating heterogeneous uptake and enhancement patterns in [F-18]FDG-PET, Tc-99m-SPECT, CT, and T-1-weighted MR images. The results of this work indicate that the phantom might be useful for the further development and optimization of imaging protocols for radiomic quantification in hybrid imaging modalities. Show less
3D printing of pediatric-centered drug formulations can provide suitable alternatives to current treatment options, though further research is still warranted for successful clinical implementation... Show more3D printing of pediatric-centered drug formulations can provide suitable alternatives to current treatment options, though further research is still warranted for successful clinical implementation of these innovative drug products. Extensive research has been conducted on the compliance of 3D-printed drug products to a pediatric quality target product profile. The 3D-printed tablets were of particular interest in providing superior dosing and release profile similarity compared to conventional drug manipulation and compounding methods, such as oral liquids. In the future, acceptance of 3D-printed tablets in the pediatric patient population might be better than current treatments due to improved palatability. Further research should focus on expanding clinical knowledge, providing regulatory guidance and expansion of the product range, including dosage form possibilities. Moreover, it should enable the use of diverse good manufacturing practice (GMP)-ready 3D printing techniques for the production of various drug products for the pediatric patient population. Show less
Three-dimensional (3D) printing of pharmaceuticals has the potential to revolutionise personalised medicine but is as yet largely unexplored. A proof-of-concept study of a novel heated, piston... Show moreThree-dimensional (3D) printing of pharmaceuticals has the potential to revolutionise personalised medicine but is as yet largely unexplored. A proof-of-concept study of a novel heated, piston-driven semi-solid extrusion 3D printer was performed by producing furosemide and sildenafil tablets for paediatric patients. The average weight of the tablets was 141.1 mg (RSD 1.26%). The acceptance values of the content uniformity were 4.2 & ndash;10.6 (concentration RSD 0.41 & ndash;0.63%), 4.8 & ndash;8.9 (concentration RSD 0.76 & ndash;0.97%) and 6.6 & ndash;9.2 (concentration RSD 0.94 & ndash;1.44%) for furosemide 2 mg, 10 mg and sildenafil 4 mg, respectively. The dissolution rate limiting step was the dissolving and eroding of the tablet matrix and showed an immediate release. The tablets complied to the requirements of the European Pharmacopoeia (EP) for uniformity of mass (EP 2.9.5), content uniformity (EP 2.9.40) and conventional release (EP 2.9.3). While they complied, not all of these quality tests for tablets might be suitable for 3D printed tablets due to the layering of the tablets and the small batch production. To assess adequate layer adhesion adjusted friability (EP 2.9.7) and resistance to crushing (EP 2.9.8) tests are proposed. Show less
Iuliano, A.; Wal, E. van der; Ruijmbeek, C.W.B.; in't Groen, S.L.M.; Pijnappel, W.W.M.P.; Greef, J.C. de; Saggiomo, V. 2020
The transition from 2D to 3D engineered tissue cultures is changing the way biologists can perform in vitro functional studies. However, there has been a paucity in the establishment of methods... Show moreThe transition from 2D to 3D engineered tissue cultures is changing the way biologists can perform in vitro functional studies. However, there has been a paucity in the establishment of methods required for the generation of microdevices and cost-effective scaling up. To date, approaches including multistep photolithography, milling and 3D printing have been used that involve specialized and expensive equipment or time-consuming steps with variable success. Here, a fabrication pipeline is presented based on affordable off-the-shelf 3D printers and novel replica molding strategies for rapid and easy in-house production of hundreds of 3D culture devices per day, with customizable size and geometry. This pipeline is applied to generate tissue engineered skeletal muscles in vitro using human induced pluripotent stem cell-derived myogenic progenitors. These production methods can be employed in any standard biomedical laboratory. Show less
Zhao, S.; Maas, M.; Jansen, K.; Hecke, M.L. van 2019
Additive manufacturing strives to combine any combination of materials into 3D functional structures and devices, ultimately opening up the possibility of 3D printed machines. It remains difficult... Show moreAdditive manufacturing strives to combine any combination of materials into 3D functional structures and devices, ultimately opening up the possibility of 3D printed machines. It remains difficult to actuate such devices, thus limiting the scope of 3D printed machines to passive devices or necessitating the incorporation of external actuators that are manufactured differently. Here, 3D printed hybrid thermoplast/conducter bilayers are explored, which can be actuated by differential heating caused by externally controllable currents flowing through their conducting faces. The functionality of such actuators is uncovered and it is shown that they allow to 3D print, in one pass, simple flexible robotic structures that propel forward under step‐wise applied voltages. Moreover, exploiting the thermoplasticity of the nonconducting plastic parts at elevated temperatures, it is shown that how strong driving leads to irreversible deformations—a form of 4D printing—which also enlarges the range of linear response of the actuators. Finally, it is shown that how to leverage such thermoplastic relaxations to accumulate plastic deformations and obtain very large deformations by alternatively driving both layers of a bilayer; this is called ratcheting. The strategy is scalable and widely applicable, and opens up a new approach to reversible actuation and irreversible 4D printing of arbitrary structures and machines. Show less
Purpose A 3D printer was used to realise compartmental dosage forms containing multiple active pharmaceutical ingredient (API) formulations. This work demonstrates the microstructural... Show morePurpose A 3D printer was used to realise compartmental dosage forms containing multiple active pharmaceutical ingredient (API) formulations. This work demonstrates the microstructural characterisation of 3D printed solid dosage forms using X-ray computed microtomography (X mu CT) and terahertz pulsed imaging (TPI).Methods Printing was performed with either polyvinyl alcohol (PVA) or polylactic acid (PLA). The structures were examined by X mu CT and TPI. Liquid self-nanoemulsifying drug delivery system (SNEDDS) formulations containing saquinavir and halofantrine were incorporated into the 3D printed compartmentalised structures and in vitro drug release determined.Results A clear difference in terms of pore structure between PVA and PLA prints was observed by extracting the porosity (5.5% for PVA and 0.2% for PLA prints), pore length and pore volume from the X mu CT data. The print resolution and accuracy was characterised by X mu CT and TPI on the basis of the computer-aided design (CAD) models of the dosage form (compartmentalised PVA structures were 7.5 +/- 0.75% larger than designed; n = 3).Conclusions The 3D printer can reproduce specific structures very accurately, whereas the 3D prints can deviate from the designed model. The microstructural information extracted by X mu CT and TPI will assist to gain a better understanding about the performance of 3D printed dosage forms. Show less
Canters, R.A.; Lips, I.M.; Wendling, M.; Kusters, M.; Zeeland, M. van; Gerritsen, R.M.; ... ; Verhoef, C.G. 2016
Background and purpose: Creating an individualized tissue equivalent material build-up (i.e. bolus) for electron beam radiation therapy is complex and highly labour-intensive. We implemented a new... Show moreBackground and purpose: Creating an individualized tissue equivalent material build-up (i.e. bolus) for electron beam radiation therapy is complex and highly labour-intensive. We implemented a new clinical workflow in which 3D printing technology is used to create the bolus.Material and methods: A patient-specific bolus is designed in the treatment planning system (TPS) and a shell around it is created in the TPS. The shell is printed and subsequently filled with silicone rubber to make the bolus. Before clinical implementation we performed a planning study with 11 patients to evaluate the difference in tumour coverage between the designed 3D-print bolus and the clinically delivered plan with manually created bolus. For the first 15 clinical patients a second CT scan with the 3D-print bolus was performed to verify the geometrical accuracy.Results: The planning study showed that the V85% of the CTV was on average 97% (3D-print) vs 88% (conventional). Geometric comparison of the 3D-print bolus to the originally contoured bolus showed a high similarity (DSC = 0.89). The dose distributions on the second CT scan with the 3D print bolus in position showed only small differences in comparison to the original planning CT scan.Conclusions: The implemented workflow is feasible, patient friendly, safe, and results in high quality dose distributions. This new technique increases time efficiency. (C) 2016 Elsevier Ireland Ltd. All rights reserved. Show less
