**Acknowledgements**

This research was supported by Australian Research Council Discovery Project (DP150101717). Jingyu Liu acknowledges the financial support from the China Scholarship Council and a Top-Up scholarship from Queensland University of Technology.

#### **Author details**

Jingyu Liu and Cheng Yan\*

\*Address all correspondence to: c2.yan@qut.edu.au

School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), Brisbane, Queensland, Australia

#### **References**


[3] Fischenich KM, Lewis JT, Bailey TS, Haut Donahue TL. Mechanical viability of a thermoplastic elastomer hydrogel as a soft tissue replacement material. Journal of the Mechanical Behavior of Biomedical Materials. 2018;**79**:341-347

**4. Conclusion**

148 3D Printing

and respond to it.

**Author details**

**References**

Jingyu Liu and Cheng Yan\*

**Acknowledgements**

In conclusion, it is clear from the results discussed in this review that there is a huge potential for applying 3D printing in tissue engineering. 3D printing offers unique advantages toward flexible manufacturing, which can be employed to fabricate scaffolds with complex shape and internal porous structure. To improve the biological performance of printed scaffolds, it is crucial to choose suitable biomaterials introduced in Section 2, and it is equally important to select an appropriate printing technology discussed in Section 3. Although we have got great progress in the processing technique, we are still a long way from printing functional artificial tissue to completely substitute human tissue. To the best of our knowledge, 3D printing cannot build a bulk scaffold over one centimeter while possessing feature size at nanoscale. The precise control of scaffold structure, surface morphology and pore size is still a huge challenge for current 3D printing methods. In addition, post-processing is inevitable for most 3D printing methods, which limit the development of in-situ printing method. Moreover, there is a need for a significant amount of research to be carried out in order to understand the bioactive reaction between host tissue and biomaterials. With increasing research efforts in this field, we believe that future developments of novel biomaterials and processing techniques will lead us to a biocompatible artificial tissue that is smart enough to detect an event

This research was supported by Australian Research Council Discovery Project (DP150101717). Jingyu Liu acknowledges the financial support from the China Scholarship Council and a

School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty,

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\*Address all correspondence to: c2.yan@qut.edu.au


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**Chapter 8**

**Provisional chapter**

**3D Printing Planning Stereotactic Radiosurgery in**

**3D Printing Planning Stereotactic Radiosurgery in** 

DOI: 10.5772/intechopen.79032

The aim of our work is to use a new modality for visualization of intraocular tumors in three-dimensional space for planning of stereotactic radiosurgery procedure on linear accelerator. Malignant uveal melanoma is the most common malignant tumor of the inner eye structures in adults. Stereotactic radiosurgery on linear accelerator is the method of treatment that requires precise planning. However, in some cases, it is very difficult to imagine the structures based only on fusion of two-dimensional computed tomography (CT) and magnetic resonance imaging (MRI) scans. For the team of specialists planning the procedure, 3D printed models represent the way how to perceive the real shape of the tumor and its location considering the important structures of the eye globe. By using the open-source software for segmentation (3D Slicer), we created a virtual 3D model of the eye globe with a tumor that utilized tissue density information based on CT and/or MRI dataset. By creating and introducing a new imaging modality for tumor visualization, we provided real 3D model of the eye globe for the specialists that enabled them more effective planning of the stereotactic

**Keywords:** fused deposition modeling, intraocular melanoma, stereotactic

Recent development of 3D printing enables to produce models of things, shapes, objects, and structures that before seemed more or less not possible to achieve. These technologies can

radiosurgery, 3D printer, 3D eye globe model

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,

distribution, and reproduction in any medium, provided the original work is properly cited.

**Uveal Melanoma Patients**

**Uveal Melanoma Patients**

Robert Furda and Gabriel Kralik

Robert Furda and Gabriel Kralik

http://dx.doi.org/10.5772/intechopen.79032

**Abstract**

radiosurgery.

**1. Introduction**

Alena Furdova, Adriana Furdova, Miron Sramka,

Alena Furdova, Adriana Furdova, Miron Sramka,

Additional information is available at the end of the chapter

Additional information is available at the end of the chapter


#### **3D Printing Planning Stereotactic Radiosurgery in Uveal Melanoma Patients 3D Printing Planning Stereotactic Radiosurgery in Uveal Melanoma Patients**

DOI: 10.5772/intechopen.79032

Alena Furdova, Adriana Furdova, Miron Sramka, Robert Furda and Gabriel Kralik Alena Furdova, Adriana Furdova, Miron Sramka, Robert Furda and Gabriel Kralik

Additional information is available at the end of the chapter Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.79032

#### **Abstract**

[72] Miao S, Zhu W, Castro NJ, Nowicki M, Zhou X, Cui H, Fisher JP, Zhang LG. 4D printing smart biomedical scaffolds with novel soybean oil epoxidized acrylate. Scientific

[73] Zarek M, Mansour N, Shapira S, Cohn D. 4D printing of shape memory-based personalized endoluminal medical devices. Macromolecular Rapid Communications. 2017;**38**(2)

[74] Morrison RJ, Hollister SJ, Niedner MF, Mahani MG, Park AH, Mehta DK, Ohye RG, Green GE. Mitigation of tracheobronchomalacia with 3D-printed personalized medical

devices in pediatric patients. Science Translational Medicine. 2015;**7**(285):285ra64

Reports. 2016;**6**:27226

154 3D Printing

The aim of our work is to use a new modality for visualization of intraocular tumors in three-dimensional space for planning of stereotactic radiosurgery procedure on linear accelerator. Malignant uveal melanoma is the most common malignant tumor of the inner eye structures in adults. Stereotactic radiosurgery on linear accelerator is the method of treatment that requires precise planning. However, in some cases, it is very difficult to imagine the structures based only on fusion of two-dimensional computed tomography (CT) and magnetic resonance imaging (MRI) scans. For the team of specialists planning the procedure, 3D printed models represent the way how to perceive the real shape of the tumor and its location considering the important structures of the eye globe. By using the open-source software for segmentation (3D Slicer), we created a virtual 3D model of the eye globe with a tumor that utilized tissue density information based on CT and/or MRI dataset. By creating and introducing a new imaging modality for tumor visualization, we provided real 3D model of the eye globe for the specialists that enabled them more effective planning of the stereotactic radiosurgery.

**Keywords:** fused deposition modeling, intraocular melanoma, stereotactic radiosurgery, 3D printer, 3D eye globe model

#### **1. Introduction**

Recent development of 3D printing enables to produce models of things, shapes, objects, and structures that before seemed more or less not possible to achieve. These technologies can

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

build a 3D object in almost any shape imaginable as defined in a computer-aided design (CAD) file. In a basic setup, the 3D printer first follows the instructions in the CAD file to build the foundation for the object, moving the head of the printer along the x-y plane. The printer then continues to follow the instructions, moving the head of the printer along the z-axis to build the object vertically layer by layer. It is important to note that two-dimensional (2D) radiographic images, such as x-rays, magnetic resonance imaging (MRI), or computed tomography (CT) scans, can be converted to digital 3D print files, allowing the creation of customized anatomical and medical structures [1].

volumes from 10 to 150 picoliters. Droplet size can vary by adjusting the applied temperature

3D Printing Planning Stereotactic Radiosurgery in Uveal Melanoma Patients

http://dx.doi.org/10.5772/intechopen.79032

157

FDM printers are less expensive and more common than the SLS type. An FDM printer uses a head of the printer that is similar with an inkjet printer. However, instead of ink, as the printer's head moves, beads of heated plastic are released and build the object in thin layers. This process is often repeated, allowing precise control of the location and amount of each deposit to shape each layer. Since the plastic is heated as it is extruded, it bonds or fuses with the layers below. As each layer of material cools, it hardens and creates the solid object as the layers build. Depending on the complexity and cost of an FDM printer, it may have features such as multiple heads of the printer. FDM printers can use a variety

3D printing was introduced to medicine at the beginning of this century, when the technology was first used to create dental implants and individualized prosthetics. Since then, the medical applications for 3D printing technology have progressed significantly. The first published reviews describe the importance, utilization and results of 3D printing when applied in the field of orthopedic surgery, cardiovascular surgery, and tissue engineering, as well as in pharmaceutical development (new dosage forms, delivery of medicines, etc.). The current medical application of 3D printing technology is classified into several groups, such as prosthetics, implantation, and precise anatomical models; production of tissues and organs; and research in pharmaceutical industry on drug discovery, design of dispensers, and drug

3D printing technology has progressed to the point when companies print custom-made eyewear with their own design and on demand. The market for customization of eyewear has been made possible by a rapid prototyping. 3D printing enables and simplifies on demand production of medical devices in plastic or metallic form, and in the future, may represent the best way to produce artificial lenses, glaucoma valves and other personalized

3D printed models are already used in institutions for medical education—due to their accurate visualization are being used to introduce surgical techniques to trainees, young doctors or students before they start to treat patients. Surgical simulations using 3D models

gradient, pulse frequency, and viscosity of the ink.

**1.3. Fused deposition modeling**

**2. 3D printing in ophthalmology**

**2.1. 3D printing for eyewear and medical devices**

**2.2. For education and clinical practice**

of plastics [3].

dosage forms [4].

implants.

Charles Hull invented 3D printing, which he called "stereolithography," in the early 1980s. Stereolithography uses the ".stl" file format to interpret the data in a CAD file, allowing specific instructions to be electronically communicated to the 3D printer. Along with dimensions, the data in the ".stl" file may also contain additional information for 3D printer such as the color, texture, and thickness of the object. Hull later founded the company 3D Systems, which developed the first 3D printer, called a "stereolithography apparatus." In 1988, 3D Systems introduced the first commercially available 3D printer, the SLA-250. Many other companies have since developed 3D printers for commercial applications. Hull's study, as well as advances made by other researchers, had revolutionized manufacturing, and it was applied in many other fields, as well as in medicine research and practice [2].

Nowadays, many of 3D printing processes are available, and all of them offer advantages and disadvantages. The model of 3D printer selected for an appliance depends on the material types that should be used, and it depends on the required layers in the finished model they are supposed to be bonded. The used 3D printing technologies within medical applications are: selective laser sintering (SLS), thermal inkjet (TIJ) printing, and fused deposition modeling (FDM).

#### **1.1. Selective laser sintering**

An SLS printing technology uses as a substrate for printing new objects, a powdered material. The laser renders the shape of the object into a single layer of powder bonding the powder particles together. Then, a new layer of powder is laid down and the process repeats on and on, building layer by layer to form the object. Selective laser sintering can be used to create metal, plastic, and ceramic objects. The accuracy of the laser and the fineness of the powder material are limited by the degree of detail. This detail enables to create especially detailed and delicate structures, like the eye globe and its structures (lens, optic disc).

#### **1.2. Thermal inkjet printing**

Thermal inkjet printing is a "noncontact" technique that uses piezoelectric, thermal, or electromagnetic technology to deposit tiny droplets of ink or other materials that are used onto a substrate according to digital instructions. Heating of the head of the printer creates small air bubbles that collapse and create pressure pulses that eject ink droplets from nozzles in volumes from 10 to 150 picoliters. Droplet size can vary by adjusting the applied temperature gradient, pulse frequency, and viscosity of the ink.

#### **1.3. Fused deposition modeling**

build a 3D object in almost any shape imaginable as defined in a computer-aided design (CAD) file. In a basic setup, the 3D printer first follows the instructions in the CAD file to build the foundation for the object, moving the head of the printer along the x-y plane. The printer then continues to follow the instructions, moving the head of the printer along the z-axis to build the object vertically layer by layer. It is important to note that two-dimensional (2D) radiographic images, such as x-rays, magnetic resonance imaging (MRI), or computed tomography (CT) scans, can be converted to digital 3D print files, allowing the creation of

Charles Hull invented 3D printing, which he called "stereolithography," in the early 1980s. Stereolithography uses the ".stl" file format to interpret the data in a CAD file, allowing specific instructions to be electronically communicated to the 3D printer. Along with dimensions, the data in the ".stl" file may also contain additional information for 3D printer such as the color, texture, and thickness of the object. Hull later founded the company 3D Systems, which developed the first 3D printer, called a "stereolithography apparatus." In 1988, 3D Systems introduced the first commercially available 3D printer, the SLA-250. Many other companies have since developed 3D printers for commercial applications. Hull's study, as well as advances made by other researchers, had revolutionized manufacturing, and it was applied in many other fields, as well as in medicine research

Nowadays, many of 3D printing processes are available, and all of them offer advantages and disadvantages. The model of 3D printer selected for an appliance depends on the material types that should be used, and it depends on the required layers in the finished model they are supposed to be bonded. The used 3D printing technologies within medical applications are: selective laser sintering (SLS), thermal inkjet (TIJ) printing, and fused deposition model-

An SLS printing technology uses as a substrate for printing new objects, a powdered material. The laser renders the shape of the object into a single layer of powder bonding the powder particles together. Then, a new layer of powder is laid down and the process repeats on and on, building layer by layer to form the object. Selective laser sintering can be used to create metal, plastic, and ceramic objects. The accuracy of the laser and the fineness of the powder material are limited by the degree of detail. This detail enables to create especially detailed

Thermal inkjet printing is a "noncontact" technique that uses piezoelectric, thermal, or electromagnetic technology to deposit tiny droplets of ink or other materials that are used onto a substrate according to digital instructions. Heating of the head of the printer creates small air bubbles that collapse and create pressure pulses that eject ink droplets from nozzles in

and delicate structures, like the eye globe and its structures (lens, optic disc).

customized anatomical and medical structures [1].

and practice [2].

156 3D Printing

ing (FDM).

**1.1. Selective laser sintering**

**1.2. Thermal inkjet printing**

FDM printers are less expensive and more common than the SLS type. An FDM printer uses a head of the printer that is similar with an inkjet printer. However, instead of ink, as the printer's head moves, beads of heated plastic are released and build the object in thin layers. This process is often repeated, allowing precise control of the location and amount of each deposit to shape each layer. Since the plastic is heated as it is extruded, it bonds or fuses with the layers below. As each layer of material cools, it hardens and creates the solid object as the layers build. Depending on the complexity and cost of an FDM printer, it may have features such as multiple heads of the printer. FDM printers can use a variety of plastics [3].
