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Abstract

The paper describes an innovative ultrasound imaging method called Doppler Tomography (DT), otherwise known as Continuous Wave Ultrasonic Tomography (CWUT). Thanks to this method, it is possible to image the tissue cross-section in vivo using a simple two-transducer ultrasonic probe and using the Doppler effect. It should be noted that DT significantly differs from the conventional ultrasound Doppler method of measuring blood flow velocity. The main difference is that when measuring blood flow, we receive information with an image of the velocity distribution in a given blood vessel (Nowicki, 1995), while DT allows us to obtain a cross-sectional image of stationary tissue structure. In the conventional method, the probe remains stationary, while in the DT method, the probe moves and the examined tissue remains stationary.

This paper presents a method of image reconstruction using the DT method. First, the basic principle of correlation of generated Doppler frequencies with the location of inclusions from which they originate is explained. Then the exact process and algorithm in this method are presented. Finally, the impact of several key parameters on imaging quality is examined. As a result, the conclusions of the research allow to improve the image reconstruction process using the DT method.

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Authors and Affiliations

Tomasz Świetlik
Krzysztof J. Opieliński
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Abstract

Designers of all types of equipment applied in oxygenation and aeration need to get to know the mechanism behind the gas bubble formation. This paper presents a measurement method used for determination of parameters of bubbles forming at jet attachment from which the bubles are displaced upward. The measuring system is based on an optical tomograph containing five projections. An image from the tomograph contains shapes of the forming bubbles and determine their volumes and formation rate. Additionally, this paper presents selected theoretical models known from literature. The measurement results have been compared with simple theoretical models predictions. The paper also contains a study of the potential to apply the presented method for determination of bubble structures and observation of intermediate states.

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Authors and Affiliations

Mariusz R. Rząsa
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Abstract

Ultrasound is used for breast cancer detection as a technique complementary to mammography, the standard screening method. Current practice is based on reflectivity images obtained with conventional instruments by an operator who positions the ultrasonic transducer by hand over the patient’s body. It is a non-ionizing radiation, pain-free and not expensive technique that provides a higher contrast than mammography to discriminate among fluid-filled cysts and solid masses, especially for dense breast tissue. However, results are quite dependent on the operator’s skills, images are difficult to reproduce, and state-of-the-art instruments have a limited resolution and contrast to show micro-calcifications and to discriminate between lesions and the surrounding tissue. In spite of their advantages, these factors have precluded the use of ultrasound for screening.

This work approaches the ultrasound-based early detection of breast cancer with a different concept. A ring array with many elements to cover 360◦ around a hanging breast allows obtaining repeatable and operator-independent coronal slice images. Such an arrangement is well suited for multi-modal imaging that includes reflectivity, compounded, tomography, and phase coherence images for increased specificity in breast cancer detection. Preliminary work carried out with a mechanical emulation of the ring array and a standard breast phantom shows a high resolution and contrast, with an artifact-free capability provided by phase coherence processing.

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Authors and Affiliations

Jorge Camacho
Luis Medina
Jorge F. Cruza
José M. Moreno
Carlos Fritsch
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Abstract

Extremely intense development of civilization requires from foundry casting technologies very high quality and not expensive castings. In

the foundries, there are many treatments that allow increasing of the final properties of produced castings such as refining, modification,

heat treatment, etc. One of the methods of increasing the quality of the casting by removing inclusions from the liquid alloy is filtration.

The use of ceramic-carbon foam filters in filtration process is still analysed phenomenon that allows improving the final properties of

castings. A modern method of research, testing and synthesis of innovative chemical compositions allows improving the properties of such

filters. In the paper the evaluation of application properties of developed ceramic-carbon bonded foam filters is presented. The quality of

the foam filters is evaluated by Computer Tomography and foundry trials in pouring of liquid metal in test molds. Additionally computer

simulations were made to visualize the flow characteristics in the foam filter. The analysed filters are the result of the research work of

Foundry Research Institute and the Institute of Ceramics and Building Materials, Refractory Materials Department in Gliwice.

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Authors and Affiliations

A. Karwiński
P. Wieliczko
M. Małysza
A. Gil
B. Lipowska
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Abstract

The paper presents an analysis of the results of ultrasound transmission tomography (UTT) imaging of the internal structure of a breast elastography phantom used for biopsy training, and compares them with the results of CT, MRI and, conventional US imaging; the results of the phantom examination were the basis for the analysis of UTT method resolution. The obtained UTT, CT and MRI images of the CIRS Model 059 breast phantom structure show comparable (in the context of size and location) heterogeneities inside it. The UTT image of distribution of the ultrasound velocity clearly demonstrates continuous changes of density. The UTT image of derivative of attenuation coefficient in relation to frequency is better for visualising sharp edges, and the UTT image of the distribution of attenuation coefficient visualises continuous and stepped changes in an indirect way. The inclusions visualized by CT have sharply delineated edges but are hardly distinguishable from the phantom gel background even with increased image contrast. MRI images of the studied phantom relatively clearly show inclusions in the structure. Ultrasonography images do not show any diversification of the structure of the phantom. The obtained examination results indicate that, if the scanning process is accelerated, ultrasound transmission tomography method can be successfully used to detect and diagnose early breast malignant lesions. Ultrasonic transmission tomography imaging can be applied in medicine for diagnostic examination of women’s breasts and similarly for X-ray computed tomography, while eliminating the need to expose patients to the harmful ionising radiation.
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Authors and Affiliations

Krzysztof J. Opieliński
Tadeusz Gudra
Piotr Pruchnicki
Przemysław Podgórski
Tomasz Kraśnicki
Jacek Kurcz
Marek Sąsiadek
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Abstract

The exact measurement of multiphase flow is an important and essential task in the oil and petrochemical related industries. Several methods have already been proposed in this field. In the existing methods, flow rate measurement depends on the fluid flow pattern. Flow pattern recognition requiring calibration has created instability in such systems. In this paper, a imple and reliable method is proposed which is based on ultrasonic tomography. It is free from calibration and instability problems that existing methods have. The obtained data from a 32-digit array of ultrasonic sensors have been used and the two-phase flow rate including liquid and gas phases have been calculated through a simple algebraic algorithm. Simulation results show that while applying this method the measurement technique is independent from the fluid flow pattern and the system error is decreased. For the proposed algorithm, the average amount of the spatial imaging error (SIE) for a bubble at different positions inside the pipe is about 5%.

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Authors and Affiliations

Omid Qorbani
Esmaeil Najafi Aghdam
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Abstract

Optical coherence tomography (OCT) – a kind of optical counterpart of ultrasound imaging – is continually being improved as image contrast boosting techniques are developed.

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Authors and Affiliations

Karol Karnowski
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Abstract

Computed tomography is opening up new possibilities for the diagnosis of coronary artery disease. If used routinely as a future screening method, it can detect the disease at a very early stage.
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Authors and Affiliations

Cezary Kępka
1

  1. Institute of Cardiology in Warsaw
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Abstract

During four Polish Geodynamical Expeditions to West Antarctica between 1979 and 1991, seismic measurements were made along 21 deep refraction profiles in the Bransfield Strait and along the coastal area of Antarctic Peninsula using explosion sources. Recordings were made by 16 land stations and 8 ocean bottom seismometers. Good quality recordings were obtained up to about 250 km distance. This allowed a detailed study of the seismic wave field and crustal structure. Three-dimensional tomographic inversion was carried out using first arriv­als from the complete data set including off-line recordings. As a result, we obtained a 3-D model of the P-wave velocity distribution in the study area. In the area adjacent to the Antarctic Peninsula coast, sedimentary cover of 0.2 to 3 km thickness was found, whereas in the shelf area and in the Bransfield Strait sedimentary basins with thickness from 5 to 8 km were observed. In the Bransfield Strait a high velocity body with Vp > 7.5 km/s was found at 12 km depth. The use of the off-line data allowed for determination of the horizontal extent of the body. The thickness of the crust varies from more than 35-40 km in the coastal area south of the Hero Fracture Zone to 30-35 km in the area of Bransfield Strait and South Shetland Islands and about 12 km in the Pacific Ocean NW of South Shetland Islands.

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Authors and Affiliations

Piotr Środa
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Abstract

The main objective of this study was to assess the environmental impact of the subsurface geological structure in Nam Son landfill by hydrogeophysical method. The Electrical Resistivity Tomography (ERT), Self- -Potential (SP) and Very Low Frequency (VLF) method was used for geological structure investigation. Three profiles (total 900 m long) of two-dimensional ERT, VLF density sections and 180 SP data points scattered within the study area near the disposal site were implemented. Surface water and groundwater samples were collected from 10 sites in the area for hydrochemical analysis. Interpretations of geophysical data show a low resistivity zone (<15 Ω m), which appears to be a fully saturated zone with leachate from an open dumpsite. There is a good correlation between the geophysical investigations and the results of hydrochemical analysis.
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Authors and Affiliations

Nguyen Van Giang
Nguyen Trong Vu
Nguyen Ba Duan
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Abstract

This paper presents and analyses the results of a simulation of the acoustic field distribution in sectors of a 1024-element ring array, intended for the diagnosis of female breast tissue with the use of ultrasonic tomography. The array was tested for the possibility to equip an ultrasonic tomograph with an additional modality - conventional ultrasonic imaging with the use of individual fragments (sections) of the ring array. To determine the acoustic field for sectors of the ring array with a varying number of activated ultrasonic transducers, a combined sum of all acoustic fields created by each elementary transducer was calculated. By the use of MATLAB software, a unique algorithm was developed, for a numerical determination of the distribution of pressure of an ultrasonic wave on any surface or area of the medium generated by the concave curvilinear structure of rectangular ultrasound transducers with a geometric focus of the beam. The analysis of the obtained results of the acoustic field distribution inside the ultrasonic ring array used in tomography allows to conclude that the optimal number of transducers in a sector enabling to obtain ultrasound images using linear echographic scanning is 32 ≤ n ≤ 128, taking into account that due to an increased temporal resolution of ultrasonic imaging, this number should be as low as possible.

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Authors and Affiliations

Wiktor Staszewski
Tadeusz Gudra
Krzysztof J. Opieliński
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Abstract

The paper presents a review of current achievements in the Electrical Capacitance Tomography (ECT) in relation to its possible applications in the study of phenomena occurring in fluidised bed reactors. Reactors of that kind are being increasingly used in chemical engineering, energetics (fluidised bed boilers) or industrial dryers. However, not all phenomena in the fluidised bed have been thoroughly understood. This results in the need to explore and develop new research methods. Various aspects of ECT operation and data processing are described with their applicability in scientific research. The idea for investigation of temperature distribution in the fluidised bed, using multimodal tomography, is also introduced. Metrological requirements of process tomography such as sensitivity, resolution, and speed of data acquiring are noted.

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Authors and Affiliations

Jan Porzuczek
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Abstract

An optical tomograph in which a tested object is illuminated from five directions has been presented in the paper. The measurements of luminous intensity after changing into discrete signals (0 or 1) in the detectors equipped with 64 optical sensors were subjected to reconstruction by means of the matrix algorithm. Detailed description of the measuring sensor, as well as the principles of operation of the electronic system, has been given in the paper. Optical phenomena occurring at the phase boundary while transmitted through the sensor wall and phenomena inside the measuring space have also been taken into account. The method of the sensor calibration has been analysed and a way of technical solution of the problem under consideration has been discussed. The elaborated method has been tested using objects of the known shape and dimensions. It was found that reconstruction of the shapes of moving bubbles and determination of their main parameters is also possible with a reasonable accuracy.

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Authors and Affiliations

Mariusz R. Rząsa
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Abstract

Optical Coherence Tomography (OCT) is one of the most rapidly advancing techniques. This method is capable of non-contact and non-destructive investigation of the inner structure of a broad range of materials. Compared with other methods which belong to the NDE/NDT group (Non-Destructive Evaluation/Non-Destructive Testing methods), OCT is capable of a broad range of scattering material structure visualization. Such a non-invasive and versatile method is very demanded by the industry. The authors applied the OCT method to examine the corrosion process in metal samples coated by polymer films. The main aim of the research was the evaluation of the anti-corrosion protective coatings using the OCT method. The tested samples were exposed to a harsh environment. The OCT measurements have been taken at different stages of the samples degradation. The research and tests results have been presented, as well as a brief discussion has been carried out.

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Authors and Affiliations

Paulina Antoniuk
Marcin Strąkowski
Jerzy Pluciński
Bogdan Kosmowski
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Abstract

This paper presents a preoperative hip reconstruction method with diagnosed osteoarthritis using Durom Hip Resurfacing System (DHRS). The method is based on selection and application of the resurfacing to the pelvis reconstructed on the basis of computed tomography. Quality and geometrical parameters of distinguished tissues have a fundamental significance for locating and positioning the acetabular and femoral components. The application precedes the measurements of anatomical structures on a complex numerical model. The developed procedure enables functional selection of endo-prosthesis and its positioning in such a way that it secures geometric parameters within the bone bed and the depth , inclination angles and ante-version of the acetabular component, the neck-shaft angle and ante-torsion angle of the neck of the femoral bone, and reconstruction of the biomechanical axis of the limb and the physiological point of rotation in the implanted joint. Proper biomechanics of the bone-joint complex of the lower limb is determined by correlation of anatomical-geometrical parameters of the acetabular component and parameters of the femoral bone.

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Authors and Affiliations

Anna M. Ryniewicz
Łukasz Bojko
Tomasz Madej
Andrzej Ryniewicz
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Abstract

Hydroxyapatite (HAp) has been attracting widespread interest in medical applications. In a form of coating, it enables to create a durable bond between an implant and surrounding bone tissues. With addition of silver nanoparticles HAp should also provide antibacterial activity. The aim of this research was to evaluate the composition of hydroxyapatite with silver nanoparticles in a non-destructive and non-contact way. For control measurements of HAp molecular composition and solvent evaporation efficiency the Raman spectroscopy has been chosen. In order to evaluate dispersion and concentration of the silver nanoparticles inside the hydroxyapatite matrix, the optical coherence tomography (OCT) has been used. Five samples were developed and examined ‒ a reference sample of pure HAp sol and four samples of HAp colloids with different silver nanoparticle solution volume ratios. The Raman spectra for each solution have been obtained and analyzed. Furthermore, a transverse-sectional visualization of every sample has been created and examined by means of OCT.

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Authors and Affiliations

Maciej J. Głowacki
Marcin Gnyba
Paulina Strąkowska
Mateusz Gardas
Maciej Kraszewski
Michał Trojanowski
Marcin R. Strąkowski
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Abstract

The electrical impedance diagnostic methods and instrumentation developed at the Gdansk and Warsaw Universities of Technology are described. On the basis of knowledge of their features, several original approaches to the broad field of electrical impedance applications are discussed. Analysis of electrical field distribution after external excitation, including electrode impedance, is of primary importance for measurement accuracy and determining the properties of the structures tested.

Firstly, the problem of electrical tissue properties is discussed. Particular cells are specified for in vitro and in vivo measurements and for impedance spectrometry. Of especial importance are the findings concerning the electrical properties of breast cancer, muscle anisotropy and the properties of heart tissue and flowing blood. The applications are both important and wide-ranging but, for the present, special attention has been focused on the evaluation of cardiosurgical interventions.

Secondly, methods of instrument construction are presented which use an electrical change in conductance, such as impedance pletysmography and cardiography, for the examination of total systemic blood flow. A new method for the study of right pulmonary artery blood flow is also introduced. The basic applications cover examination of the mechanical activity of the heart and evaluation of many haemodynamic parameters related to this. Understanding the features that occur during blood flow is of major importance for the proper interpretation of measurement data.

Thirdly, the development of electrical impedance tomography (EIT) is traced for the purposes of determining the internal structure of organs within the broad field of 2-D and 3-D analysis and including modelling of the organs being tested, the development of reconstruction algorithms and the construction of hardware.

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Authors and Affiliations

A. Nowakowski
T. Palko
J. Wtorek
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Abstract

At the current stage of diagnostics and therapy, it is necessary to perform a geometric evaluation of facial skull bone structures basing upon virtually reconstructed objects or replicated objects with reverse engineering. The objective hereof is an analysis of imaging precision for cranial bone structures basing upon spiral tomography and in relation to the reference model with the use of laser scanning. Evaluated was the precision of skull reconstruction in 3D printing, and it was compared with the real object, topography model and reference model. The performed investigations allowed identifying the CT imaging accuracy for cranial bone structures the development of and 3D models as well as replicating its shape in printed models. The execution of the project permits one to determine the uncertainty of components in the following procedures: CT imaging, development of numerical models and 3D printing of objects, which allows one to determine the complex uncertainty in medical applications.

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Bibliography

[1] D. Mitsouras, P. Liacouras, A. Imanzadeh, A.A. Giannopoulos, T. Cai, K.K. Kumamaru, and V.B. Ho. Medical 3D printing for the radiologist. RadioGraphics, 35(7):1965–1988, 2015. doi: 10.1148/rg.2015140320.
[2] F. Paulsen and J. Wasche. Sobotta Atlas of Human Anatomy, General anatomy and musculoskeletal system. Vol. 1, 2013.
[3] G.B. Kim, S. Lee, H. Kim, D.H. Yang, Y.H. Kim, Y.S. Kyung, and S.U. Kwon. Threedimensional printing: basic principles and applications in medicine and radiology. Korean Journal of Radiology, 17(2):182–197, 2016. doi: 10.3348/kjr.2016.17.2.182.
[4] J.W. Choi and N. Kim. Clinical application of three-dimensional printing technology in craniofacial plastic surgery. Archives of Plastic Surgery, 42(3):267–277, 2015. doi: 10.5999/aps.2015.42.3.267.
[5] J.E. Loster, M.A. Osiewicz, M. Groch, W. Ryniewicz, and A. Wieczorek. The prevalence of TMD in Polish young adults. Journal of Prosthodontics, 26(4):284–288, 2017. doi: 10.1111/jopr.12414.
[6] A.S. Soliman, L. Burns, A. Owrangi, Y. Lee,W.Y. Song, G. Stanisz, and B.P. Chugh. A realistic phantom for validating MRI-based synthetic CT images of the human skull. Medical Physics, 44:4687–4694, 2017. doi: 10.1002/mp.12428.
[7] F. Heckel, S. Zidowitz, T. Neumuth, M. Tittmann, M. Pirlich, and M. Hofer. Influence of image quality on semi-automatic 3D reconstructions of the lateral skull base for cochlear implantation. In CURAC, 129–134, 2016.
[8] G. Budzik, T. Dziubek, and P. Turek. Basic factors affecting the quality of tomographic images. Problems of Applied Sciences, 3:77–84, 2015. (in Polish)
[9] S. Singare, C. Shenggui and N. Li. The Benefit of 3D Printing in Medical Field: Example Frontal Defect Reconstruction. Journal of Material Sciences & Engineering, 6(2):335, 2017. doi: 10.4172/2169-0022.1000335.
[10] A. Ryniewicz, K. Ostrowska, R. Knapik, W. Ryniewicz, M. Krawczyk, J. Sładek, and Ł. Bojko. Evaluation of mapping of selected geometrical parameters in computer tomography using standards. Przegląd Elektrotechniczny, 91(6):88–91, 2015. (in Polish) doi: 10.15199/48.2015.06.17.
[11] R. Kaye, T. Goldstein, D. Zeltsman, D.A. Grande, and L.P. Smith. Three dimensional printing: a review on the utility within medicine and otolaryngology. International Journal of Pediatric Otorhinolaryngology, 89:145-148, 2016. doi: 10.1016/j.ijporl.2016.08.007.
[12] G.T. Grant and P.C. Liacouras. Craniofacial Applications of 3D Printing. In: 3D Printing in Medicine: A Practical Guide for Medical Professionals. Rybicki, Frank J., Grant, Gerald T. (Eds.), Springer, Cham, Switzerland, pp. 43–50, 2017. doi: 10.1007/978-3-319-61924-8_5.
[13] T. Cai, F.J. Rybicki, A.A. Giannopoulos, K. Schultz, K.K. Kumamaru, P. Liacouras, and D. Mitsouras. The residual STL volume as a metric to evaluate accuracy and reproducibility of anatomic models for 3D printing: application in the validation of 3D-printable models of maxillofacial bone from reduced radiation dose CT images. 3D Printing in Medicine, 1(1):2, 2015. doi: 10.1186/s41205-015-0003-3.
[14] T.Y. Hsieh, B. Cervenka, R. Dedhia, E.B. Strong, and T. Steele. Assessment of a patient- specific, 3-dimensionally printed endoscopic sinus and skull base surgical model. JAMA Otolaryngology–Head & Neck Surgery, 144(7):574-579, 2018. doi: 10.1001/jamaoto.2018.0473.
[15] Y.W. Chen, C.T. Shih, C.Y. Cheng, and Y.C. Lin. The development of skull prosthesis through active contour model. Journal of Medical Systems, 41:164, 2017. doi: 10.1007/s10916-017-0808-2.
[16] J.S. Naftulin, E.Y. Kimchi, and S.S. Cash. Streamlined, inexpensive 3D printing of the brain and skull. PLoS One, 10(8):e0136198, 2015. doi: 10.1371/journal.pone.0136198.
[17] A. Ryniewicz, K. Ostrowska, Ł. Bojko, and J. Sładek. Application of non-contact measurement methods for the evaluation of mapping the shape of solids of revolution. Przegląd Eletrotechniczny, 91(5):21–24, 2015. (in Polish). doi: 10.15199/48.2015.05.06.
[18] V. Favier, N. Zemiti, O.C. Mora, G. Subsol, G. Captier, R. Lebrun. and B. Gilles. Geometric and mechanical evaluation of 3D-printing materials for skull base anatomical education and endoscopic surgery simulation – A first step to create reliable customized simulators. PloS One, 12(12): e0189486, 2017. doi: 10.1371/journal.pone.0189486.
[19] M.P. Chae,W.M. Rozen, P.G. McMenamin, M.W. Findlay, R.T. Spychal, and D.J. Hunter-Smith. Emerging applications of bedside 3D printing in plastic surgery. Frontiers in Surgery, 2:25, 2015. doi: 10.3389/fsurg.2015.00025.
[20] J.A. Sładek. Coordinate Metrology. Accuracy of Systems and Measurements. Springer, 2015.
[21] ISO 15530-3:2011: Geometrical product specifications (GPS) – Coordinate measuring machines (CMM): Technique for determining the uncertainty of measurement – Part 3: Use of calibrated workpieces or measurement standards.
[22] A. Marro, T. Bandukwala, and W. Mak. Three-dimensional printing and medical imaging: a review of the methods and applications. Current Problems in Diagnostic Radiology, 45(1): 2–9, 2016. doi: 10.1067/j.cpradiol.2015.07.009.
[23] A. Ryniewicz. Evaluation of the accuracy of the surface shape mapping of elements of biobearings in in vivo and in vitro tests. Scientific Works of the Warsaw University of Technology. Mechanics, 248:3–169, 2013. (in Polish).
[24] B.M. Mendez, M.V. Chiodo, and P.A. Patel. Customized “In-Office” three-dimensional printing for virtual surgical planning in craniofacial surgery. The Journal of Craniofacial Surgery, 26(5):1584–1586, 2015. doi: 10.1097/SCS.0000000000001768.
[25] J.J. de Lima Moreno, G.S. Liedke, R. Soler, H.E.D. da Silveira, and H.L.D. da Silveira. Imaging factors impacting on accuracy and radiation dose in 3D printing. Journal of Maxillofacial and Oral Surgery, 17(4):582–587, 2018. doi: 10.1007/s12663-018-1098-z.
[26] S.W. Park, J.W. Choi, K.S. Koh and T.S. Oh. Mirror-imaged rapid prototype skull model and pre-molded synthetic scaffold to achieve optimal orbital cavity reconstruction. Journal of Oral and Maxillofacial Surgery, 73(8):1540–1553, 2015. doi: 10.1016/j.joms.2015.03.025.
[27] K.M. Day, P.M. Phillips, and L.A. Sargent. Correction of a posttraumatic orbital deformity using three-dimensional modeling. Virtual surgical planning with computer-assisted design, and three-dimensional printing of custom implants. Craniomaxillofacial Trauma and Reconstruction, 11(01):078–082, 2018. doi: 10.1055/s-0037-1601432.
[28] Y.C. Lin, C.Y. Cheng, Y.W. Cheng, and C.T. Shih. Skull repair using active contour models. Procedia Manufacturing, 11: 2164–2169, 2017. doi: 10.1016/j.promfg.2017.07.362.
[29] J.N. Winer, F.J. Verstraete, D.D. Cissell, S. Lucero, K.A. Athanasiou and B. Arzi. The application of 3-dimensional printing for preoperative planning in oral and maxillofacial surgery in dogs and cats. Veterinary Surgery, 46(7):942–951, 2017. doi: 10.1111/vsu.12683.
[30] J.Y. Lim, N. Kim, J.C. Park, S.K. Yoo, D.A. Shin, and K.W. Shim. Exploring for the optimal structural design for the 3D-printing technology for cranial reconstruction: a biomechanical and histological study comparison of solid vs. porous structure. Child’s Nervous System, 33(9):1553–1562, 2017. doi: 10.1007/s00381-017-3486-y.
[31] W. Shui, M. Zhou, S. Chen, Z. Pan, Q. Deng, Y. Yao, H. Pan, T. He, and X. Wang. The production of digital and printed resources from multiple modalities using visualization and three-dimensional printing techniques. International Journal of Computer Assisted Radiology and Surgery, 12(1):13–23, 2017. doi: 10.1007/s11548-016-1461-9.
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Authors and Affiliations

Andrzej Ryniewicz
1 2
Wojciech Ryniewicz
3
Stanisław Wyrąbek
1
Łukasz Bojko
4

  1. Cracow University of Technology, Faculty of Mechanical Engineering, Poland.
  2. State University of Applied Science, Nowy Sącz, Poland.
  3. Jagiellonian University Medical College, Faculty of Medicine, Dental Institute, Department of Dental Prosthodontics, Cracow, Poland.
  4. AGH University of Science and Technology, Faculty of Mechanical Engineering and Robotics, Department of Machine Design and Technology, Cracow, Poland.
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Abstract

Casting porosity is the main factor influencing the fatigue properties of Al-Si alloys. Due to the increasing use of aluminum castings, porosity characterization is useful for estimating their fatigue strength. In principle, a combination of metallographic techniques and statistical pore analysis is a suitable approach for predicting the largest defect size that is critical for the casting. Here, the influence of modifiers and casting technology on the largest pore size population in AlSi7Mg alloy specimens is obtained and discussed adopting the Murakami's approach. However, porosity evaluation is a challenge in the case of microshrinkage pores, which are frequently found in industrial castings. Their complicated morphology prevents a reliable definition of an equivalent defect size based on metallographic techniques. This contribution reports the application of X-ray tomography to the 3D reconstruction of real pores in cast Al-Si alloys and provides insight into the complication of microshrinkage pore sizing by metallography.

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Authors and Affiliations

Stanislava Fintová
Giancarlo Anzelotti
Radomila Konečná
Gianni Nicoletto
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Abstract

Authors paid attention to anatomy and clinical implications which are associated with the variations of the sphenoid sinus. We discuss also anatomical structure of the sphenoid bone implementing clinical application of this bone to diff erent invasive and miniinvasive procedures (i.e. FESS).

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Authors and Affiliations

Joanna Jaworek-Troć
Michał Zarzecki
Anna Bonczar
Lourdes N. Kaythampillai
Bartosz Rutowicz
Małgorzata Mazur
Jacenty Urbaniak
Wojciech Przybycień
Katarzyna Piątek-Koziej
Marcin Kuniewicz
Marcin Lipski
Wojciech Kowalski
Janusz Skrzat
Marios Loukas
Jerzy Walocha
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Abstract

New oil and natural gas deposits can be recognized using X-ray computed tomography (CT) technology, and their potential value can be evaluated using increasingly advanced computational methods.

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Authors and Affiliations

Paulina Krakowska
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Abstract

We present spectral emission characteristics from laser-plasma EUV/SXR sources produced by irradiation of < 1 J energy laser pulse on eleven different double stream gas puff targets, with most intense electronic transitions identified in the spectral range from 1 nm to 70 nm wavelength which corresponds to photon energy from 18 eV to 1240 eV. The spectra were obtained using grazing incidence and transmission spectro- graphs from laser-produced plasma emission, formed by the interaction of a laser beam with a double stream gas puff target. Laser pulses with a duration of 4 ns and energy of 650 mJ were used for the experiment. We present the results obtained from three different spectrometers in the wavelength ranges of SXR (1–5.5 nm), SXR/EUV (4–15.5 nm), and EUV (10–70 nm). In this paper, detailed information about the source, gas targets under investigation, the experimental setup, spectral measurements and the results are presented and discussed. Such data may be useful for the identification of adequate spectral emissions from gasses in the EUV and SXR wavelength ranges dedicated to various experiments (i.e. broadband emission for the X-ray coherence tomography XCT) or may be used for verification of magnetohydrodynamic plasma codes.

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Authors and Affiliations

Antony Jose Arikkatt
Przemysław Wachulak
Henryk Fiedorowicz
Andrzej Bartnik
Joanna Czwartos
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Abstract

This study was carried out to determine the morphometric and volumetric features of the mandible in Van cats by using computed tomography (CT) and a three-dimensional (3D) software program. The study also aimed at presenting the biometrical differences of these mea- surements between genders. A total of 16 adult Van cats (8 males, 8 females) were used in the study. The cats were anesthetized using a ketamine-xylazine combination. They were then scanned using CT under anesthesia and their images were obtained. The scanned images of the mandible in each cat were used for the reconstruction of a 3D model by using the MIMICS 20.1 (The Materialise Group, Leuven, Belgium) software program. Later, morphometric (17 parame- ters), volumetric, and surface area measurements were conducted and statistical analyses were carried out. In our morphometric measurements, it was found that TLM (total length of the mandible), PCD (pogonion to coronoid process distance), CAP (length from the indenta- tion between the condyle process and angular process to pogonion), CAC (length from the inden- tation between the condyle process and the angular process to back of alveole C1), CML (length between C1 - M1), RAH (ramus height), MDM (mandible depth at M1), MHP (height of the mandible in front of P3), and ABC (angular process to back of alveole C1 distance) were greater in male cats; while MWM (mandible width at M1 level) was greater in female cats and was statistically significant (p<0.05). The length and height of the mandible were 6.36±2.42 cm and 3.01±1.81 cm in male cats, respectively. On the other hand, in female cats, the length and height of the mandible were 5.89±2.57 cm and 2.71±1.26 cm, respectively. The volume of the mandible was measured to be 7.39±0.93 cm3 in male cats and 5.40±0.49 cm3 in female cats. The surface areas were 63.50±5.27 cm2 in male cats and 52.73±3.89 cm2 in female cats. In con- clusion, in this study, basic morphometric parameters of the mandible in adult Van cats were found by using CT and a 3D modeling program. The differences between male and female cats were also determined in the study.
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Authors and Affiliations

O. Yilmaz
1
İ. Demircioglu
2

  1. Department of Anatomy, Faculty of Veterinary Medicine, Van Yuzuncu Yil University, 65080, Van, Turkey
  2. Department of Anatomy, Faculty of Veterinary Medicine, Harran University, 63200, Şanlıurfa, Turkey

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