Process types of customisation and personalisation in design for additive manufacturing applied to vascular models

Manufacturing companies face high demand for products that fulfil individual customer desires. Recent improvements in additive manufacturing (AM) enable the fabrication of customer-specific components of a product. This paper presents a categorisation of design processes for customised and personalised products through the use of AM in three process types: special design, specific adaptation, and standardised individualisation. The characteristics of design processes are examined in medical development of vascular models integrated into a modular neurovascular training setup. The paper considers how initial customer involvement and preplanning of customer-specification influence the design process for varying degrees of individualisation enabled by additive manufacturing

Process types of customisation and personalisation in design for additive manufacturing applied to vascular models

Manufacturing companies face high demand for products that fulfil individual customer desires. Recent improvements in additive manufacturing (AM) enable the fabrication of customer-specific components of a product. This paper presents a categorisation of design processes for customised and personalised products through the use of AM in three process types: special design, specific adaptation, and standardised individualisation. The characteristics of design processes are examined in medical development of vascular models integrated into a modular neurovascular training setup. The paper considers how initial customer involvement and preplanning of customer-specification influence the design process for varying degrees of individualisation enabled by additive manufacturing

Comparing Technologies of Additive Manufacturing for the Development of Modular Dosimetry Phantoms in Radiation Therapy

In radiotherapy, X-ray imaging and dose quality assurance is often carried out using physical phantoms, which simulate the X-ray attenuation of biological tissue. Additive manufacturing (AM) allows to produce cost-effective phantoms that can easily be adapted to different purposes. The aim of this work was to compare mechanical and X-ray attenuation properties of a selection of AM technologies, machines, and materials. The average Hounsfield Units (HU) were measured by means of computed tomography (CT)

3D printing of intracranial aneurysms using fused deposition modeling offers highly accurate replications

BACKGROUND AND PURPOSE: As part of a multicenter cooperation (Aneurysm-Like Synthetic bodies for Testing Endovascular devices in 3D Reality) with focus on implementation of additive manufacturing in neuroradiologic practice, we systematically assessed the technical feasibility and accuracy of several additive manufacturing techniques. We evaluated the method of fused deposition modeling for the production of aneurysm models replicating patient-specific anatomy. MATERIALS AND METHODS: 3D rotational angiographic data from 10 aneurysms were processed to obtain volumetric models suitable for fused deposition modeling. A hollow aneurysm model with connectors for silicone tubes was fabricated by using acrylonitrile butadiene styrene. Support material was dissolved, and surfaces were finished by using NanoSeal. The resulting models were filled with iodinated contrast media. 3D rotational angiography of the models was acquired, and aneurysm geometry was compared with the original patient data. RESULTS: Reproduction of hollow aneurysm models was technically feasible in 8 of 10 cases, with aneurysm sizes ranging from 41 to 2928 mm3 (aneurysm diameter, 3-19 mm). A high level of anatomic accuracy was observed, with a mean Dice index of 93.6% ± 2.4%. Obstructions were encountered in vessel segments of <1 mm. CONCLUSIONS: Fused deposition modeling is a promising technique, which allows rapid and precise replication of cerebral aneurysms. The porosity of the models can be overcome by surface finishing. Models produced with fused deposition modeling may serve as educational and research tools and could be used to individualize treatment planning

Detection of flow dynamic changes in 3D printed aneurysm models after treatment

Treatment success and potential relapse of intracranial aneurysms need to be followed-up by regular imaging. However, the metallic material inside treated aneurysms can cause artifacts in MRI, CT and DSA possibly compromising clinical interpretation. Furthermore, frequent follow-ups with X-ray based imaging methods seriously increase the patient’s exposure to ionizing radiation. Thus, magnetic particle imaging (MPI) may be beneficial for patients with treated aneurysms. The purpose of this work was to demonstrate the capability of MPI to depict the change of the contrast agent dynamics of aneurysms after treatment. Realistic aneurysm models before and after treatment by different means were connected to a peristaltic pump with a physiologic flow (250 ml/min) and pulsation rate (70/min). Contrast agent curves over time were measured during injection of a 3 ml bolus within 3 s of an aqueous solution of 50 mmol(Fe)/L. MPI was able to detect the expected delay and dispersion of the contrast agent in the treated aneurysm as well as a less filling with contrast agent, if densely packed material was present inside the aneurysm. The delay was estimated based on the MPI contrast agent curves to be in the order of about 1 s. Thus, MPI is capable to detect delay and dispersion of the contrast agent dynamics after aneurysm treatment with clinical standard metallic material

Design for Mass Adaptation of the Neurointerventional Training Model HANNES with Patient-Specific Aneurysm Models

A neurointerventional training model called HANNES (Hamburg ANatomical NEurointerventional Simulator) has been developed to replace animal models in catheter-based aneurysm treatment training. A methodical approach to design for mass adaptation is applied so that patient-specific aneurysm models can be designed recurrently based on real patient data to be integrated into the training system. HANNES’ modular product structure designed for mass adaptation consists of predefined and individualized modules that can be combined for various training scenarios. Additively manufactured, individualized aneurysm models enable high reproducibility of real patient anatomies. Due to the implementation of a standardized individualization process, order-related adaptation can be realized for each new patient anatomy with modest effort. The paper proves how the application of design for mass adaptation leads to a well-designed modular product structure of the neurointerventional training model HANNES, which supports quality treatment and provides an animal-free and patient-specific training environment

Magnetic particle imaging for high temporal resolution assessment of aneurysm hemodynamics

The purpose of this work was to demonstrate the capability of magnetic particle imaging (MPI) to assess the hemodynamics in a realistic 3D aneurysm model obtained by additive manufacturing. MPI was compared with magnetic resonance imaging (MRI) and dynamic digital subtraction angiography (DSA)

Cyclic repetition of the 4D pc-fq MRI (top) shows distinct pulsation and a much lower flow velocity inside the aneurysm.

<p>Dynamic MRI (second top, cubic spline interpolated), MPI (second bottom), and DSA (bottom) also show distinct pulsation and delayed contrast agent dynamics inside the aneurysm. Regions were chosen in the corresponding image data as depicted in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0160097#pone.0160097.g001" target="_blank">Fig 1</a>. Pulsations and bolus injections did not perfectly match between the different methods, due to the resetting of the experiments.</p

False color (left) and vector field (right) visualization of the 4D pc-fq MRI at the time point of maximal flow velocity during one pulsation cycle.

<p>Lower flow velocity and different flow directions are clearly visible inside the aneurysm. Movies showing all phases of the pulsation are available as <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0160097#pone.0160097.s002" target="_blank">S1</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0160097#pone.0160097.s003" target="_blank">S2</a> Videos.</p