Anatomical Models Research Articles

Equine anatomy with body painting: a model for the learning of topographic anatomy

The teaching of anatomy faces new challenges due to the decrease in the number of hours dedicated to this course in the current curricula worldwide, and because today's students demand new methodologies and strategies that make learning more didactic, effective, and applicable to real professional needs. The body painting technique is a method that has been used for several years in human anatomy teaching, which has recently begun to be used in veterinary anatomy teaching. This article describes the elaboration of a horse’s live anatomical model by students of the veterinary anatomy course using body painting, within the “Exhibition and Contest of Anatomical Models, a six-monthly event held at the Faculty of Agrarian Sciences of the University of Antioquia (Medellín, Colombia). The model was made to show the academic community an alternative way of approaching topographic and surface anatomy with an applied focus through a more didactic and understandable methodology for the student. This article also shows the surface anatomy of various horses’ body systems through the body painting technique. This learning methodology has great acceptance among students and is currently used within the practices of the new curriculum of the Veterinary Anatomy course at the University of Antioquia.

Microbial Transfer by Intermittent Catheters: An In Vitro Evaluation of Microbial Transfer in Catheter With Variable Protective Features.

The purpose of this study was to evaluate the effects of various protective features (eg, catheter cap, introducer tip, and catheter sleeve) of hydrophilic intermittent catheters against contamination with urinary tract infection-associated microorganisms using an in vitro model. An in vitro study of microbial transfer. Gloves were contaminated with uropathogenic microorganisms and used to simulate intermittent catheterization of male anatomical models with and without the protective features present in 5 commercially available hydrophilic catheters. Using this contaminated touch transfer method, both the meatus of the sterile male anatomical models and sterile surgical gloves of an operator were inoculated with a high level of microorganisms (107 and 109 colony-forming units [CFU], respectively). The operator then performed catheterization of the anatomical model. The most relevant segments of the catheter were sampled, and the level of microbial transfer and catheter contamination was quantified. Results from experimental and sample replicates from the 3 microbial species and 5 catheters (sleeved and unsleeved) were analyzed by pair-wise t tests and analysis of variance. Of the 5 commercially available sleeved intermittent catheters evaluated in this study, use of catheters with multiple protective components (ring cap, introducer tip, and catheter sleeve) resulted in significant improvement in protection against contamination with a 25- to 2500-fold lower level of microbial contamination (C1 segment) across all species as compared to catheters protected with only sleeves or un-sleeved catheters. The combination of a ring cap, protective introducer tip, and protective sleeve provides additional protection when compared to sleeve alone from transferring microbial contamination from the meatus to the advancing catheter. Additional research is needed to determine whether these design features result in fewer urinary tract infections among intermittent catheter users.

Learning effectiveness of clinical anatomy and practical spine surgery skills using a new VR-based training platform

IntroductionAs medical education becomes more complex, the demand for advanced teaching and training methods has grown. Technological advancements have opened up new possibilities, particularly in the realm of virtual reality (VR) simulations for training. Research QuestionOur prospective, randomized pilot study aims to assess whether a novel VR-based 3D training platform can effectively teach the knowledge and skills needed for complex spinal surgery, specifically pedicle screw placement. Material and MethodsWe enrolled 25 participants who received either a traditional lecture (control group, n=11) or a VR lecture with identical content featuring 3D/VR anatomical models (VR group, n=14). The VR group also underwent VR simulation for pedicle screw placement. We evaluated their learning through a quiz, a practical skills test, and selfassessment questionnaires. ResultsIn the theory multiple-choice test, the contral group scored an average of 69% (range 53-87%, SD 0.10), while the VR group scored 66% (range 47-87%, SD 0.11) (p=0.692, independent sample t-test).For the practical DOPS test (pedicle screw placement), the average score was 2.4 points (n=25; range 1-4). The VR group on average scored 2.9 points compared to the control (2 points) (p=0.134). Discussion and Conclusion Our study indicates that teaching with a new 3D VR training tool yields results comparable to traditional methods in terms of knowledge retention. This research supports the platform's effectiveness as an educational resource. Importantly, trainees can apply VR-acquired knowledge to real surgical procedures, which are well-received.

Assessing views and attitudes toward the use of extended reality and its implications in neurosurgical education: a survey of neurosurgical trainees.

Extended reality (XR) systems, including augmented reality (AR), virtual reality (VR), and mixed reality, have rapidly emerged as new technologies capable of changing the way neurosurgeons prepare for cases. Thus, the authors sought to evaluate the perspectives of neurosurgical trainees on the integration of these technologies into neurosurgical education. A 20-question cross-sectional survey was administered to neurosurgical residents and fellows to evaluate perceptions of the use of XR in neurosurgical training. Respondents evaluated each statement using a modified Likert scale (1-5). One hundred sixteen responses were recorded, with 59.5% of participants completing more than 90% of the questions. Approximately 59% of participants reported having institutional access to XR technologies. The majority of XR users (72%) believed it was effective for simulating surgical situations, compared with only 41% for those who did not have access to XR. Most respondents (61%) agreed that XR could become a standard in neurosurgical education and a cost-effective training tool (60%). Creating patient-specific anatomical XR models was considered relatively easy by 56% of respondents. Those with XR access reported finding it easier to create intraoperative models (58%) than those without access. A significant percentage (79%) agreed on the need for technical skill training outside the operating room (OR), especially among those without XR access (82%). There was general agreement (60%) regarding the specific need for XR. XR was perceived as effectively simulating stress in the OR. Regarding clinical outcomes, 61% believed XR improved efficiency and safety and 48% agreed it enhanced resection margins. Major barriers to XR integration included lack of ample training hours and/or time to use XR amid daily clinical obligations (63%). The data presented in this study indicate that there is broad agreement among neurosurgical trainees that XR holds potential as a training modality in neurosurgical education. Moreover, trainees who have access to XR technologies tend to hold more positive perceptions regarding the benefits of XR in their training. This finding suggests that the availability of XR resources can positively influence trainees' attitudes and beliefs regarding the utility of these technologies in their education and training.

Effect of vitamin E–enhanced highly cross-linked polyethylene on wear rate and particle debris in anatomic total shoulder arthroplasty: a biomechanical comparison to ultrahigh-molecular-weight polyethylene

Particle-induced osteolysis resulting from polyethylene wear remains a source of implant failure in anatomic total shoulder designs. Modern polyethylene components are irradiated in an oxygen-free environment to induce cross-linking, but reducing the resulting free radicals with melting or heat annealing can compromise the component's mechanical properties. Vitamin E has been introduced as an adjuvant to thermal treatments. Anatomic shoulder arthroplasty models with a ceramic head component have demonstrated that vitamin E-enhanced polyethylene show improved wear compared with highly cross-linked polyethylene (HXLPE). This study aimed to assess the biomechanical wear properties and particle size characteristics of a novel vitamin E-enhanced highly cross-linked polyethylene (VEXPE) glenoid compared to a conventional ultrahigh-molecular-weight polyethylene (UHMWPE) glenoid against a cobalt chromium molybdenum (CoCrMo) head component. Biomechanical wear testing was performed to compare the VEXPE glenoid to UHMWPE glenoid with regard to pristine polyethylene wear and abrasive endurance against a polished CoCrMo alloy humeral head in an anatomic shoulder wear-simulation model. Cumulative mass loss (milligrams) was recorded, and wear rate calculated (milligrams per megacycle [Mc]). Under pristine wear conditions, particle analysis was performed, and functional biologic activity (FBA) was calculated to estimate particle debris osteolytic potential. In addition, 95% confidence intervals for all testing conditions were calculated. The average pristine wear rate was statistically significantly lower for the VEXPE glenoid compared with the HXLPE glenoid (0.81 ± 0.64 mg/Mc vs. 7.00 ± 0.45 mg/Mc) (P<.05). Under abrasive wear conditions, the VEXPE glenoid had a statistically significant lower average wear rate compared with the UHMWPE glenoid comparator device (18.93 ± 5.80 mg/Mc vs. 40.47 ± 2.63 mg/Mc) (P<.05). The VEXPE glenoid demonstrated a statistically significant improvement in FBA compared with the HXLPE glenoid (0.21 ± 0.21 vs. 1.54 ± 0.49 (P<.05). A newanatomic glenoid component with VEXPE demonstrated significantly improved pristine and abrasive wear properties with lower osteolytic particle debris potential compared with a conventional UHMWPE glenoid component. Vitamin E-enhanced polyethylene shows early promise in shoulder arthroplasty components. Long-term clinical and radiographic investigation needs to be performed to verify if these biomechanical wear properties translate to diminished long-term wear, osteolysis, and loosening.

A Review of 3D Printing and Surgical Planning

Three-Dimensional Printing (3DP), also known as rapid prototyping or additive manufacturing, has revolutionized the field of medicine, particularly in preoperative planning. By transforming intricate Two-Dimensional (2D) medical imaging data into tangible, patient-specific Three-Dimensional (3D) models, 3DP enhances surgical precision and patient care. This technology facilitates detailed preoperative visualization, enabling surgeons to interact with accurate anatomical models, plan complex procedures, and anticipate potential challenges. The evolution of 3DP, driven by advances in Fused Deposition Modeling (FDM), Selective Laser Sintering (SLS), and Stereolithography (SLA), has democratized access to affordable and sophisticated 3D printers, spurring innovation in medical applications. In this study, a comprehensive review of the literature on the integration of 3DP technology into preoperative planning is conducted. Applications across various surgical disciplines, including cardiovascular, orthopedic, craniofacial, neurosurgical, oncological, transplant, and pediatric surgeries are examined. Benefits of 3DP in providing tactile feedback, creating patient-specific surgical guides and implants, and enhancing surgical simulation and training are evaluated. Additionally, challenges associated with the high costs, time-intensive processes, and material limitations of 3DP are assessed. Findings demonstrate that 3DP significantly reduces operative times, improves surgical outcomes, and lowers complication rates. The study highlights the transformative impact of 3DP on surgical practice and underscores its potential for future advancements. With ongoing research and innovation in materials science, bioprinting, artificial intelligence, and augmented reality, 3DP is poised to further revolutionize preoperative planning, offering more personalized, precise, and patient-centered healthcare solutions.

Comparing flow-based and anatomy-based features in the data-driven study of nasal pathologies

In several problems involving fluid flows, computational fluid dynamics (CFD) provides detailed quantitative information and allows the designer to successfully optimize the system by minimizing a cost function. Sometimes, however, one cannot improve the system with CFD alone, because a suitable cost function is not readily available; one notable example is diagnosis in medicine. The application considered here belongs to the field of rhinology; a correct air flow is key for the functioning of the human nose, yet the notion of a functionally normal nose is not available and a cost function cannot be written. An alternative and attractive pathway to diagnosis and surgery planning is offered by data-driven methods. In this work, we consider the machine learning study of nasal impairment caused by anatomic malformations, with the aim of understanding whether fluid dynamic features, available after a CFD analysis, are more effective than purely geometric features at the training of a neural network for regression. Our experiments are carried out on an extremely simplified anatomic model and a correspondingly simple CFD approach; nevertheless, they show that flow-based features perform better than geometry-based ones and allow the training of a neural network with fewer inputs, a crucial advantage in fields like medicine.

Construction of a laparoscopic appendectomy model.

Appendectomy is the standard treatment for appendicitis, with the laparoscopic technique offering benefits like lower infection rates and quicker recovery. However, residents often have their first practical experience with the procedure on real patients, increasing surgical risks. In this context, medical simulation emerges as a crucial methodology, allowing professionals to experience a variety of scenarios while preventing harm to patients. The objective of this study is to describe the production of an "ex-vivo" simulation model for laparoscopic appendectomy. Cold ceramic structures were used to manually shape the anatomical model of the appendix, ensuring its rigidity. On this model, we poured materials to create a flexible mold using acetic silicone. Once the mold was made, we filled it with thermo-moldable styrene polymer rubber, along with dye, and fused it at a specific temperature. This process resulted in the manufacture of a piece that simulates the appendix, being tear-resistant and suturable, faithfully replicating the structure and characteristics of a human organ. The low weight of the materials facilitates transport, allowing them to be reproduced and used in various situations, from training in hospital settings to universities. The model is applicable in didactic simulations with medical students, residents, and surgeons. Its ease of production and low cost contribute to the practices being repeatable, ensuring a better development of surgical skills. This work not only contributes to the advancement of medical simulation but also highlights the importance of innovative and collaborative solutions in improving medical education and promoting patient safety.

Three-dimensional anatomical modeling of cases with atrial septal defect and ventricular septal defect, which are congenital heart anomalies

Three-dimensional anatomical modeling of cases with atrial septal defect and ventricular septal defect, which are congenital heart anomalies

Finite Element Analysis for the Virtual Surgical Planning of Stiffness-matched Personalized Load-bearing Percutaneous Implants

Osseointegrated, percutaneous intramedullary abutments provide a new opportunity to increase freedom of movement, dexterity, and power of prosthetic upper and lower extremities. Device deployment is based on the physician’s experience and judgment as no biomechanical information is available or choice of implant location, shape, and materials. Furthermore, there is little opportunity for personalization to improve performance and reduce the risk of stress shielding-induced bone loss or stress concentration-induced device failure. We present a Virtual Surgical Planning (VSP) environment for assessing the expected mechanical outcome of physician choice in the placement site of a percutaneous implant. Starting from de-identified patient images, a virtual anatomical model is created to emulate the surgical implantation procedure. After digitally implanting the intramedullary component-abutment system, the mechanical performance is computationally evaluated via Finite Element Analysis (FEA) under representative in vivo static loading conditions. Our computational analysis includes two different materials for the implant: medical-grade Surgical Grade 5 Titanium alloy (Ti-6Al-4V) and super-elastic Nickel-Titanium (NiTi). The resulting analysis can inspire future design personalization and deployment in an open surgical procedure. Our VSP approach would allow interactive assessment of device location, materials, and performance to alter the normal stress-strain distribution in the bone, potentially avoiding stress shielding and device failure. Future stiffness-matching strategies (e.g., incorporation of internal porosity, new materials, or novel implant geometry), and their effect on implant strength could be evaluated in our computational model.

An Open-Source Software Approach to Multimodal Medical Imaging: Combination of Anatomical and Thermal 3D Models

As the three-dimensional (3D) reconstruction and visualisation of medical imaging systems, such as computed tomography (CT) and magnetic resonance imaging (MRI), become common approaches for assisting physicians with a visual representation of anatomy structures, a novelty approach adding functional elements of the human body started being explored. So, medical thermography has been used as a complementary imaging technique for diagnosis and monitoring of pathologies, based on the identification of surface temperature changes. Therefore, this paper presents a new open-source software approach to multimodal medical imaging. The proposed methodology involves the 3D reconstruction of an anatomical model and thermal model, being the latter based on a Structure from Motion (SfM) approach, and the combination of both models, providing a complete 3D multimodal model that contains inner information regarding the anatomy of the body, and outer physiological information. It showed efficient results regarding the visualisation of the multimodal model in a single coordinate system in different views (axial, coronal, and sagittal), allowing it to be inspected by physicians, whilst improving pathology assessment. The 3D multimodal models have potential to be expanded to medical applications, such as diagnosis, surgery, and follow-up care, whilst being cost effective by resorting to available open-source software.

Visuo-Haptic VR and AR Guidance for Dental Nerve Block Education.

The inferior alveolar nerve block (IANB) is a dental anesthetic injection that is critical to the performance of many dental procedures. Dental students typically learn to administer an IANB through videos and practice on silicone molds and, in many dental schools, on other students. This causes significant stress for both the students and their early patients. To reduce discomfort and improve clinical outcomes, we created an anatomically informed virtual reality headset-based educational system for the IANB. It combines a layered 3D anatomical model, dynamic visual guidance for syringe position and orientation, and active force feedback to emulate syringe interaction with tissue. A companion mobile augmented reality application allows students to step through a visualization of the procedure on a phone or tablet. We conducted a user study to determine the advantages of preclinical training with our IANB simulator. We found that in comparison to dental students who were exposed only to traditional supplementary study materials, dental students who used our IANB simulator were more confident administering their first clinical injections, had less need for syringe readjustments, and had greater success in numbing patients.

Treatment Planning Strategies for Interstitial Ultrasound Ablation of Prostate Cancer.

To develop patient-specific 3D models using Finite-Difference Time-Domain (FDTD) simulations and pre-treatment planning tools for the selective thermal ablation of prostate cancer with interstitial ultrasound. This involves the integration with a FDA 510(k) cleared catheter-based ultrasound interstitial applicators and delivery system. A 3D generalized "prostate" model was developed to generate temperature and thermal dose profiles for different applicator operating parameters and anticipated perfusion ranges. A priori planning, based upon these pre-calculated lethal thermal dose and iso-temperature clouds, was devised for iterative device selection and positioning. Full 3D patient-specific anatomic modeling of actual placement of single or multiple applicators to conformally ablate target regions can be applied, with optional integrated pilot-point temperature-based feedback control and urethral/rectum cooling. These numerical models were verified against previously reported ex-vivo experimental results obtained in soft tissues. For generic prostate tissue, 360 treatment schemes were simulated based on the number of transducers (1-4), applied power (8-20 W/cm2), heating time (5, 7.5, 10 min), and blood perfusion (0, 2.5, 5 kg/m3/s) using forward treatment modelling. Selectable ablation zones ranged from 0.8-3.0 cm and 0.8-5.3 cm in radial and axial directions, respectively. 3D patient-specific thermal treatment modeling for 12 Cases of T2/T3 prostate disease demonstrate applicability of workflow and technique for focal, quadrant and hemi-gland ablation. A temperature threshold (e.g., Tthres = 52 °C) at the treatment margin, emulating placement of invasive temperature sensing, can be applied for pilot-point feedback control to improve conformality of thermal ablation. Also, binary power control (e.g., Treg = 45 °C) can be applied which will regulate the applied power level to maintain the surrounding temperature to a safe limit or maximum threshold until the set heating time. Prostate-specific simulations of interstitial ultrasound applicators were used to generate a library of thermal-dose distributions to visually optimize and set applicator positioning and directivity during a priori treatment planning pre-procedure. Anatomic 3D forward treatment planning in patient-specific models, along with optional temperature-based feedback control, demonstrated single and multi-applicator implant strategies to effectively ablate focal disease while affording protection of normal tissues.

Impressão 3D na relação médico-paciente, relato de experiência da integração entre ensino, inovação e assistência

ABSTRACT Introduction: In the literature, several articles demonstrate patient satisfaction and better understanding of the information transmitted by the medical team, with the aid of three-dimensional pieces. Education and health are inseparable and interdependent practices, they have always been articulated, and considered crucial elements in the action process of health professionals. Thus, teachers and students of the medicine course at Universidade Federal de Pernambuco created a university extension project that aimed at the use of anatomical models printed in 3D, for the education of patients in the orthopedics and traumatology outpatient clinic. Experience Report: Over the six months of the project, 77 patients were assisted and the project employed the work of 3 teachers and 18 undergraduate students, totaling 98 people involved in the project. The actions were divided into 2 blocks: the first consisted of training the students and, in the second, the students visited the outpatient clinic, accompanied by a specialist physician in charge and used pieces printed by the students themselves, to guide the patients regarding their respective condition and provided guidance on therapy using these printed pieces. Discussion: the possibility of using this tool as an aid in medical communication opens up a vast horizon of application of 3D printing in health education. This, in turn, favors the improvement of health promotion in less developed regions, since this interaction between the health team and the community allows the promotion, protection and recovery of health, based on a horizontal dialogue, valuing and respecting the users of the health system, aiming to make them an agent and protagonist of the health and disease process. Conclusion: It can be concluded, therefore, that extension projects such as this one have enormous potential to generate impacts on medicine, the academic community and the assisted population, especially the less educated ones.

A patient-specific, interactive, multiuser, online mixed-reality neurosurgical training and planning system.

Mixed-reality simulation is an emerging tool for creating anatomical models for preoperative planning. Its use in neurosurgical training (NT) has been limited because of the difficulty in real-time interactive teaching. This study describes the development of a patient-specific, interactive mixed-reality NT system. The authors took cases of intracranial tumor resection or neurovascular compression (NVC) as examples to verify the technical feasibility and efficacy of the mixed-reality NT system for residents' training and preoperative planning. This study prospectively enrolled 40 patients who suffered from trigeminal neuralgia, hemifacial spasms, or intracranial tumors. The authors used a series of software programs to process the multimodal imaging data, followed by uploading the holographic models online. They used a HoloLens or a standard iOS device to download and display the holographic models for training. Ten neurosurgical residents with different levels of surgical experience were trained with this mixed-reality NT system. Change in surgical strategy was recorded, and a questionnaire survey was conducted to evaluate the efficacy of the mixed-reality NT system. The system allows the trainer and trainee to view the mixed-reality model with either a HoloLens or an iPad/iPhone simultaneously online at different locations. Interactive manipulation and instant updates were able to be achieved during training. A clinical efficacy validation test was conducted. The surgeons changed their exploration strategy in 48.3% of the NVC cases. For residents with limited experience in surgery, the exploration strategy for 75.0% of all patients with NVC was changed after the residents were trained with the mixed-reality NT system. Of the 60 responses for intracranial tumors, the trainee changed the surgical posture in 19 (31.7%) cases. The change of the location (p = 0.0338) and size (p = 0.0056) of craniotomy are significantly related to the experience of the neurosurgeons. The mixed-reality NT system is available for local or real-time remote neurosurgical resident training. It may effectively help neurosurgeons in patient-specific training and planning of surgery for cases of NVC and intracranial tumor. The authors expect the system to have a broader application in neurosurgery in the near future.

Uses of 3D printing and Bioprinting for pre-implant bone reconstruction in Oral Surgery

Pre-implant bone surgery in oral surgery allows to reconstruct maxillary atrophies related to traumatic, infectious or tumoral processes. In this context, the ideal biomaterial remains autogenous bone, but biomaterials (of natural or synthetic origin) allow to limit the morbidity linked to bone harvesting, and to simplify these surgical procedures. In this article, we illustrate how 3D printing technologies can be used as an adjuvant to treat bone defects of complex shape or to create anatomical models used to plan interventions. Finally, some perspectives brought by tissue engineering and bioprinting (creation of complex in vitro models) are presented.

Thermo-mechanical coupling simulation analysis of cryotherapy on real anatomical structure lung cancer model

Cryotherapy is an ideally invasive way for lung cancer. Conventional cryoablation treatment lacks precise treatment plans and evaluation methods, relying on medical images for assistance. Furthermore, the current simulations primarily employ simplistic geometric models, lacking the complexity of real structures. Consequently, our research endeavors to introduce a reconstructed 3D model based on actual lung tumor tissue and employ the thermo-mechanical coupling analysis to strategize the entire surgical procedure. Additionally, we explore the optimization of probe number and angle during the pre-treatment phase. In order to enhance the heat transfer and efficacy of killing, the inclusion of nanoparticles was implemented. The assessment of effective injury was based on the criteria of thermal and stress damage, which were visualized through the cloud images depicting temperature and stress distribution. Further, a genuine clinical case was reconstructed and refined through our simulation. It is expected to establish a comprehensive database of cases and develop an optimized surgical planning system for cryotherapy.

An automated detection and classification of brain tumor from MRIs using Water Chaotic Fruitfly Optimization (WChFO) based Deep Recurrent Neural Network (DRNN)

AbstractDue to the complexity of the images and dearth of anatomical models, it is highly difficult to accurately represent the various deformations in each component of the medical images. In recent years, a significant number of children and adults have affected from brain tumors, which is one of the most terrible types of disease affects the people around the world. Moreover, the Magnetic Resonance Imaging (MRI) based brain tumor detection is one of a significant study area in the field of medical imaging. Since, the use of computerized methods aids in the detection and treatment of disease by the medical professionals. The development of an automated method for the accurate detection and classification of tumors from brain MRIs. In this framework, a tanh normalization process is used to smooth out the input brain MRIs with less noise artefacts and improved quality. Then, a group feature extraction model is used to extract the relevant features from the normalized image, which includes both Speeded Up Robust Features (SURF) and Grey Level Co-occurrence Matrix (GLCM) features. The Water Chaotic Fruitfly Optimization (WChFO) method is used to identify the best features for increasing the speed of classifier training and testing processes with less time. Moreover, a Deep Recurrent Neural Network (DRNN) model is used to classify the type of brain tumor for accurate early diagnosis and treatment. The most well-known benchmarking datasets, like BRATS and Kaggle, employed for analysis in order to assess the effectiveness and results of the proposed brain tumor diagnosis system. By using the proposed WChFO-DRNN technique, the accuracy of the tumor detection system is increased to 99.2% with the sensitivity, specificity of 99% and time consumption of 0.2s.

Advanced Strategies for the Fabrication of Multi-Material Anatomical Models of Complex Pediatric Oncologic Cases.

The printing and manufacturing of anatomical 3D models has gained popularity in complex surgical cases for surgical planning, simulation and training, the evaluation of anatomical relations, medical device testing and patient-professional communication. 3D models provide the haptic feedback that Virtual or Augmented Reality (VR/AR) cannot provide. However, there are many technologies and strategies for the production of 3D models. Therefore, the aim of the present study is to show and compare eight different strategies for the manufacture of surgical planning and training prototypes. The eight strategies for creating complex abdominal oncological anatomical models, based on eight common pediatric oncological cases, were developed using four common technologies (stereolithography (SLA), selectie laser sinterning (SLS), fused filament fabrication (FFF) and material jetting (MJ)) along with indirect and hybrid 3D printing methods. Nine materials were selected for their properties, with the final models assessed for application suitability, production time, viscoelastic mechanical properties (shore hardness and elastic modulus) and cost. The manufacturing and post-processing of each strategy is assessed, with times ranging from 12 h (FFF) to 61 h (hybridization of FFF and SLS), as labor times differ significantly. Cost per model variation is also significant, ranging from EUR 80 (FFF) to EUR 600 (MJ). The main limitation is the mimicry of physiological properties. Viscoelastic properties and the combination of materials, colors and textures are also substantially different according to the strategy and the intended use. It was concluded that MJ is the best overall option, although its use in hospitals is limited due to its cost. Consequently, indirect 3D printing could be a solid and cheaper alternative.

Deep silicon photon-counting CT: A first simulation-based study for assessing perceptual benefits across diverse anatomies

ObjectivesTo assess perceptual benefits provided by the improved spatial resolution and noise performance of deep silicon photon-counting CT (Si-PCCT) over conventional energy-integrating CT (ECT) using polychromatic images for various clinical tasks and anatomical regions. Materials and MethodsAnthropomorphic, computational models were developed for lungs, liver, inner ear, and head-and-neck (H&N) anatomies. These regions included specific abnormalities such as lesions in the lungs and liver, and calcified plaques in the carotid arteries. The anatomical models were imaged using a scanner-specific CT simulation platform (DukeSim) modeling a Si-PCCT prototype and a conventional ECT system at matched dose levels. The simulated polychromatic projections were reconstructed with matched in-plane resolutions using manufacturer-specific software. The reconstructed pairs of images were scored by radiologists to gauge the task-specific perceptual benefits provided by Si-PCCT compared to ECT based on visualization of anatomical and image quality features. The scores were standardized as z-scores for minimizing inter-observer variability and compared between the systems for evidence of statistically significant improvement (one-sided Wilcoxon rank-sum test with a significance level of 0.05) in perceptual performance for Si-PCCT. ResultsSi-PCCT offered favorable image quality and improved visualization capabilities, leading to mean improvements in task-specific perceptual performance over ECT for most tasks. The improvements for Si-PCCT were statistically significant for the visualization of lung lesion (0.08 ± 0.89 vs. 0.90 ± 0.48), liver lesion (-0.64 ± 0.37 vs. 0.95 ± 0.55), and soft tissue structures (-0.47 ± 0.90 vs. 0.33 ± 1.24) and cochlea (-0.47 ± 0.80 vs. 0.38 ± 0.62) in inner ear. ConclusionsSi-PCCT exhibited mean improvements in task-specific perceptual performance over ECT for most clinical tasks considered in this study, with statistically significant improvement for 6/20 tasks. The perceptual performance of Si-PCCT is expected to improve further with availability of spectral information and reconstruction kernels optimized for high resolution provided by smaller pixel size of Si-PCCT. The outcomes of this study indicate the positive potential of Si-PCCT for benefiting routine clinical practice through improved image quality and visualization capabilities.