Digital Design of Medical Replicas via Desktop Systems: Shape Evaluation of Colon Parts

Abstract

In this paper, we aim at providing results concerning the application of desktop systems for rapid prototyping of medical replicas that involve complex shapes, as, for example, folds of a colon. Medical replicas may assist preoperative planning or tutoring in surgery to better understand the interaction among pathology and organs. Major goals of the paper concern with guiding the digital design workflow of the replicas and understanding their final performance, according to the requirements asked by the medics (shape accuracy, capability of seeing both inner and outer details, and support and possible interfacing with other organs). In particular, after the analysis of these requirements, we apply digital design for colon replicas, adopting two desktop systems. The experimental results confirm that the proposed preprocessing strategy is able to conduct to the manufacturing of colon replicas divided in self-supporting segments, minimizing the supports during printing. This allows also to reach an acceptable level of final quality, according to the request of having a 3D presurgery overview of the problems. These replicas are compared through reverse engineering acquisitions made by a structured-light system, to assess the achieved shape and dimensional accuracy. Final results demonstrate that low-cost desktop systems, coupled with proper strategy of preprocessing, may have shape deviation in the range of ±1 mm, good for physical manipulations during medical diagnosis and explanation.

3D Printing of Prototypes Starting from Medical Imaging: A Liver Case Study

“…In accordance with these reasonings and parameters, the final result of the two halves was remarkable, confirming the good accuracy the author found in [15] in another test case. The final prototype, although suffered from the precision of the mounting of the two halves, that could be reduced designing specific pins for insertion and closing, confirmed its good usability for 3D assessing of the medical problem.…”

“…With the rapid diffusion and easy access to 3D printing desktop systems, prototypes of the 3D models can be obtained with low cost, with good accuracy and in a relatively short time [15]. This paper reports the fundamental set-up and the key aspects of 3D printing via a desktop system, for free shapes derived from Digital Imaging and Communications in Medicine (DICOM).…”

3D Reconstruction Model of an Extra-Abdominal Desmoid Tumor: A Case Study

“…Although Permacol TM does not meet all the characteristics of an ideal material for rebuilding the chest wall because of the need to preserve the movement of the rib cage and the diaphragm, in this case, we preferred a certain elasticity at the expense of excessive rigidity, and Permacol TM achieved a good result as confirmed by a follow-up CT scan at 6 months showing no recurrences. A recent development is a CT scan with reconstructed 3D images, which could guide the production, via 3D printing technology (Bici et al, 2018;Tracy et al, 2019), of an accurate resin, polymer, metal, or degradable biomaterial prosthesis. The objectives of 3DR are the complete reproduction of sternal rib ends, maintenance of the intercostal space permeability, and reproduction of the shape of the resected specimen.…”

“…Such tumors are best approached in a multidisciplinary fashion to adequately address defects and optimize postoperative outcomes. The use of three-dimensional reconstruction (3DR) technology with automated and manual segmentation is revolutionizing many sectors and is becoming a standard tool in several areas of medicine, including education, surgical training, and patientdoctor communication (Bici et al, 2018;Bergquist et al, 2019;Guachi et al, 2019). Apart from obvious "visual" superiority, a 3D model also provides a valuable visual experience thanks to its pre-and intraoperative manipulation.…”

Finite Element Analysis of the Interaction Between an Endo-Surgical Tool and Colorectal Tissue for Setting up Force Feedback Evaluation in Virtual Reality-Based Applications

“…Due to this, simplifications must be done to achieve interactivity, often reducing simulation's accuracy in terms of stress-strain distribution and force feedback. Furthermore, geometrical modelling and FEA may be principally used to set-up virtual investigations for the preoperative plan, on the base of the characteristics of the patient [2], but also, with the recent developments of additive technologies, to obtain printed 3D models useful for planning [3][4][5]. This kind of possibilities also gained importance in training and didactics applications, where learning by doing can be also associated to different levels of difficulties and accuracy.…”