scholarly journals A Simulation-Based Methodology of Developing 3D Printed Anthropomorphic Phantoms for Microwave Imaging Systems

Diagnostics ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 376
Author(s):  
Soroush Abedi ◽  
Nadine Joachimowicz ◽  
Nicolas Phillips ◽  
Hélène Roussel
Keyword(s):  
Biological Tissues ◽  
Wide Frequency Range ◽  
Microwave Imaging ◽  
3 Dimensional ◽  
Simulation Based ◽  
Liquid Solutions ◽  
Experimental Parameters ◽  
Anthropomorphic Phantoms ◽  
3D Printed ◽  
Coupling Medium

This work is devoted to the development and manufacturing of realistic benchmark phantoms to evaluate the performance of microwave imaging devices. The 3D (3 dimensional) printed phantoms contain several cavities, designed to be filled with liquid solutions that mimic biological tissues in terms of complex permittivity over a wide frequency range. Numerical versions (stereolithography (STL) format files) of these phantoms were used to perform simulations to investigate experimental parameters. The purpose of this paper is two-fold. First, a general methodology for the development of a biological phantom is presented. Second, this approach is applied to the particular case of the experimental device developed by the Department of Electronics and Telecommunications at Politecnico di Torino (POLITO) that currently uses a homogeneous version of the head phantom considered in this paper. Numerical versions of the introduced inhomogeneous head phantoms were used to evaluate the effect of various parameters related to their development, such as the permittivity of the equivalent biological tissue, coupling medium, thickness and nature of the phantom walls, and number of compartments. To shed light on the effects of blood circulation on the recognition of a randomly shaped stroke, a numerical brain model including blood vessels was considered.

scholarly journals Development of a 3-dimensional printed tube thoracostomy task trainer: An improved methodology

2021 ◽  
Vol 6 (1) ◽  
pp. 109-113
Author(s):  
Wen Hao Chen ◽  
Shairah Radzi ◽  
Li Qi Chiu ◽  
Wai Yee Yeong ◽  
Sreenivasulu Reddy Mogali
Keyword(s):  
3D Printing ◽  
Chest Tube ◽  
Fused Deposition Modelling ◽  
3 Dimensional ◽  
Fused Deposition ◽  
Simulation Based ◽  
3D Printed ◽  
Medical Educators ◽  
Based Instruction ◽  
Training Modalities

Introduction: Simulation-based training has become a popular tool for chest tube training, but existing training modalities face inherent limitations. Cadaveric and animal models are limited by access and cost, while commercial models are often too costly for widespread use. Hence, medical educators seek a new modality for simulation-based instruction. 3D printing has seen growing applications in medicine, owing to its advantages in recreating anatomical detail using readily available medical images. Methods: Anonymised computer tomography data of a patient’s thorax was processed using modelling software to create a printable model. Compared to a previous study, 3D printing was applied extensively to this task trainer. A mixture of fused deposition modelling and material jetting technology allowed us to introduce superior haptics while keeping costs low. Given material limitations, the chest wall thickness was reduced to preserve the ease of incision and dissection. Results: The complete thoracostomy task trainer costs approximately SGD$130 (or USD$97), which is significantly cheaper compared to the average commercial task trainer. It requires approximately 118 hours of print time. The complete task trainer simulates the consistencies of ribs, intercostal muscles and skin. Conclusion: By utilising multiple 3D printing technologies, this paper aims to outline an improved methodology to produce a 3D printed chest tube simulator. An accurate evaluation can only be carried out after we improve on the anatomical fidelity of this prototype. A 3D printed task trainer has great potential to provide sustainable simulation-based education in the future.

Simulation of Cerebrospinal Fluid Leak Repair Using a 3-Dimensional Printed Model

2021 ◽  
pp. 194589242110035
Author(s):  
Muhamed A. Masalha ◽  
Kyle K. VanKoevering ◽  
Omar S. Latif ◽  
Allison R. Powell ◽  
Ashley Zhang ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Great Part ◽  
Cerebrospinal Fluid Leak ◽  
Csf Leak ◽  
Clinical Environment ◽  
Training Tool ◽  
3 Dimensional ◽  
Clinical Scenarios ◽  
Before And After ◽  
3D Printed

Background Acquiring proficiency for the repair of a cerebrospinal fluid (CSF) leak is challenging in great part due to its relative rarity, which offers a finite number of training opportunities. Objective The purpose of this study was to evaluates the use of a 3-dimensional (3D) printed, anatomically accurate model to simulate CSF leak closure. Methods Volunteer participants completed two simulation sessions. Questionnaires to assess their professional qualifications and a standardized 5-point Likert scale to estimate the level of confidence, were completed before and after each session. Participants were also queried on the overall educational utility of the simulation. Results Thirteen otolaryngologists and 11 neurosurgeons, met the inclusion criteria. A successful repair of the CSF leak was achieved by 20/24 (83.33%), and 24/24 (100%) during the first and second simulation sessions respectively (average time 04:04 ± 1.39 and 02:10 ± 01:11). Time-to-close-the-CSF-leak during the second session was significantly shorter than the first (p < 0.001). Confidence scores increased across the training sessions (3.3 ± 1.0, before the simulation, 3.7 ± 0.6 after the first simulation, and 4.2 ± 0.4 after the second simulation; p < 0.001). All participants reported an increase in confidence and believed that the model represented a valuable training tool. Conclusions Despite significant differences with varying clinical scenarios, 3D printed models for cerebrospinal leak repair offer a feasible simulation for the training of residents and novice surgeons outside the constrictions of a clinical environment.

Strategies for inclusion of growth factors into 3D printed bone grafts

2021 ◽  
Author(s):  
Alessia Longoni ◽  
Jun Li ◽  
Gabriella C.J. Lindberg ◽  
Jelena Rnjak-Kovacina ◽  
Lyn M. Wise ◽  
...  
Keyword(s):  
Growth Factors ◽  
Bone Regeneration ◽  
New Technologies ◽  
Healing Process ◽  
Bone Grafts ◽  
Biological Properties ◽  
3 Dimensional ◽  
3D Printed ◽  
Physical And Chemical ◽  
Large Bone

Abstract There remains a critical need to develop new technologies and materials that can meet the demands of treating large bone defects. The advancement of 3-dimensional (3D) printing technologies has allowed the creation of personalized and customized bone grafts, with specific control in both macro- and micro-architecture, and desired mechanical properties. Nevertheless, the biomaterials used for the production of these bone grafts often possess poor biological properties. The incorporation of growth factors (GFs), which are the natural orchestrators of the physiological healing process, into 3D printed bone grafts, represents a promising strategy to achieve the bioactivity required to enhance bone regeneration. In this review, the possible strategies used to incorporate GFs to 3D printed constructs are presented with a specific focus on bone regeneration. In particular, the strengths and limitations of different methods, such as physical and chemical cross-linking, which are currently used to incorporate GFs to the engineered constructs are critically reviewed. Different strategies used to present one or more GFs to achieve simultaneous angiogenesis and vasculogenesis for enhanced bone regeneration are also covered in this review. In addition, the possibility of combining several manufacturing approaches to fabricate hybrid constructs, which better mimic the complexity of biological niches, is presented. Finally, the clinical relevance of these approaches and the future steps that should be taken are discussed.

scholarly journals Reference Breast Phantoms for Low-Cost Microwave Imaging

2020 ◽  
Vol 14 (4) ◽  
pp. 411-415
Author(s):  
Emine Avşar Aydin ◽  
Selin Yabaci Karaoğlan
Keyword(s):  
Breast Cancer ◽  
Low Cost ◽  
Microwave Frequency ◽  
Biological Tissues ◽  
Microwave Imaging ◽  
Vector Network Analyzers ◽  
Network Analyzers ◽  
Computer Based ◽  
Breast Phantoms ◽  
Inverse Radon Transform

Microwave imaging provides an alternative method for breast cancer screening and the diagnosis of cerebrovascular accidents. Before a surgical operation, the performance of microwave imaging systems should be evaluated on anatomically detailed anthropomorphic phantoms. This paper puts forward the advances in the development of breast phantoms based on 3D printing structures filled with liquid solutions that mimic biological tissues in terms of complex permittivity in a wide microwave frequency band. In this paper; four different experimental scenarios were created, and measurements were performed, and although there are many vector network analyzers on the market, the miniVNA used in this study has been shown to have potential in many biomedical applications such as portable computer-based breast cancer detection studies. We especially investigated the reproducibility of a particular mixture and the ability of some mixes to mimic various breast tissues. Afterwards, the images similar to the experimentally created scenarios were obtained by implementing the inverse radon transform to the obtained data.

scholarly journals A Tomograph Prototype for Quantitative Microwave Imaging: Preliminary Experimental Results

2018 ◽  
Vol 4 (12) ◽  
pp. 139 ◽  
Author(s):  
Alessandro Fedeli ◽  
Manuela Maffongelli ◽  
Ricardo Monleone ◽  
Claudio Pagnamenta ◽  
Matteo Pastorino ◽  
...  
Keyword(s):  
Ad Hoc ◽  
Microwave Imaging ◽  
Experimental Results ◽  
Network Analyzer ◽  
Reconstruction Algorithms ◽  
Quantitative Reconstruction ◽  
Qualitative And Quantitative ◽  
Switching Matrix ◽  
3D Printed ◽  
Transmission Measurements

A new prototype of a tomographic system for microwave imaging is presented in this paper. The target being tested is surrounded by an ad-hoc 3D-printed structure, which supports sixteen custom antenna elements. The transmission measurements between each pair of antennas are acquired through a vector network analyzer connected to a modular switching matrix. The collected data are inverted by a hybrid nonlinear procedure combining qualitative and quantitative reconstruction algorithms. Preliminary experimental results, showing the capabilities of the developed system, are reported.

A 3-Dimensional Printed Aortic Arch Template to Facilitate the Creation of Physician-Modified Stent-Grafts

2018 ◽  
Vol 25 (5) ◽  
pp. 554-558 ◽  
Author(s):  
Pawel Rynio ◽  
Arkadiusz Kazimierczak ◽  
Tomasz Jedrzejczak ◽  
Piotr Gutowski
Keyword(s):  
Aortic Arch ◽  
Stent Graft ◽  
Left Subclavian Artery ◽  
Thoracic Endovascular Aortic Repair ◽  
Stent Grafts ◽  
Landing Zone ◽  
3 Dimensional ◽  
Improve Accuracy ◽  
3D Printed ◽  
Radiopaque Markers

Purpose: To demonstrate the utility of a 3-dimensional (3D) printed template of the aortic arch in the construction of a fenestrated and scalloped physician-modified stent-graft (PMSG). Case Report: A 73-year-old woman with descending thoracic aneurysm was scheduled for thoracic endovascular aortic repair after being disqualified for open surgery. Computed tomography angiography (CTA) revealed no proximal landing zone as the aneurysm began from the level of the left subclavian artery, so a fenestrated/scalloped PMSG was planned. To facilitate accurate placement of the openings in the graft, a 3D printed aortic arch template was prepared from the CTA data and gas sterilized. In the operating room, a Valiant stent-graft was inserted into the 3D printed template and deployed. Using ophthalmic cautery, a fenestration and a scallop were created; radiopaque markers were added. The PMSG was successfully deployed with no discrepancy between the openings and the target vessels. Conclusion: A 3D printed aortic arch template facilitates handmade fenestrations and scallops in PMSGs and may improve accuracy and quality.

scholarly journals Novel On-Demand 3-Dimensional (3-D) Printed Tablets Using Fill Density as an Effective Release-Controlling Tool

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 1872 ◽  
Author(s):  
Rishi Thakkar ◽  
Amit Raviraj Pillai ◽  
Jiaxiang Zhang ◽  
Yu Zhang ◽  
Vineet Kulkarni ◽  
...  
Keyword(s):  
Drug Release ◽  
Hydroxypropyl Methylcellulose ◽  
Amorphous State ◽  
Dosage Forms ◽  
Water Soluble ◽  
Patient Specific ◽  
3 Dimensional ◽  
Fused Deposition ◽  
3D Printed ◽  
The Impact

This research demonstrates the use of fill density as an effective tool for controlling the drug release without changing the formulation composition. The merger of hot-melt extrusion (HME) with fused deposition modeling (FDM)-based 3-dimensional (3-D) printing processes over the last decade has directed pharmaceutical research towards the possibility of printing personalized medication. One key aspect of printing patient-specific dosage forms is controlling the release dynamics based on the patient’s needs. The purpose of this research was to understand the impact of fill density and interrelate it with the release of a poorly water-soluble, weakly acidic, active pharmaceutical ingredient (API) from a hydroxypropyl methylcellulose acetate succinate (HPMC-AS) matrix, both mathematically and experimentally. Amorphous solid dispersions (ASDs) of ibuprofen with three grades of AquaSolveTM HPMC-AS (HG, MG, and LG) were developed using an HME process and evaluated using solid-state characterization techniques. Differential scanning calorimetry (DSC), powder X-ray diffraction (pXRD), and polarized light microscopy (PLM) confirmed the amorphous state of the drug in both polymeric filaments and 3D printed tablets. The suitability of the manufactured filaments for FDM processes was investigated using texture analysis (TA) which showed robust mechanical properties of the developed filament compositions. Using FDM, tablets with different fill densities (20–80%) and identical dimensions were printed for each polymer. In vitro pH shift dissolution studies revealed that the fill density has a significant impact (F(11, 24) = 15,271.147, p < 0.0001) and a strong negative correlation (r > −0.99; p < 0.0001) with the release performance, where 20% infill demonstrated the fastest and most complete release, whereas 80% infill depicted a more controlled release. The results obtained from this research can be used to develop a robust formulation strategy to control the drug release from 3D printed dosage forms as a function of fill density.

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