Annals of 3D printed medicine最新文献

Background

Tricuspid regurgitation (TR) treatments have gradually shifted toward a more interventional approach and transcatheter edge-to-edge repair (TEER) has assumed a first-order role. TriClip™ by Abbott (Menlo Park, USA) is one of the most widely used devices for tricuspid repair. TEER procedures are recognised as technically challenging, characterized by a steep learning curve. For this reason, specialized training is necessary. The aim of this work is to develop and test a novel 3D printed training simulator, which considers both anatomical and mechanical characteristics, specifically designed for this kind of procedure.

Methods

Starting from routinely acquired computed tomography (CT) images, a 3D digital model of the heart was reconstructed. This was then properly “augmented”, so that it could realistically reproduce the key features involved in the procedure. The simulator was manufactured exploiting the Polyjet 3D printed. Proper materials selection was performed to accurately reproduce mechanical properties. The manufactured prototype was then tested by a specialized professional, with the TriClip™ system.

Results

The simulator was assessed to practice access, navigation, catheter steering and leaflet grasping. Throughout the process, appropriately placed cameras ensured that the operators could visualize the crucial steps on a screen. Even if a deeper evaluation is needed, preliminary feedback is satisfactory.

Conclusions

In this study, a new training simulator for TriClip™ procedure was designed, produced, and preliminary assessed. Further studies will have to demonstrate the advantages of using this simulator design to shorten the learning curve and subsequently lead to better clinical outcomes.

Background

Compartment syndrome is a medical emergency. It should be diagnosed promptly, and therapeutic measures should be taken to avoid limb ischemia. Measurement of compartment pressure is extremely important.

Model

Knowledge about compartments and familiarity with the pressure monitoring device are important to diagnose acute compartment syndrome properly. Simulations provide an opportunity to learn the device and practice the procedure. Given their lower cost and the possibility of frequent reproduction, simulations using 3D-printed material are gaining popularity. We propose a simple low-fidelity model using a silicone-based lower leg soft tissue, 3D-printed tibia and fibula, Foley catheter, and syringes.

Conclusion

This low-fidelity simulator helps to improve procedural skills and retention through repeated practice.

Introduction

Distal radius fractures make up around 20% of adult fractures, varying in type and severity, thus requiring different treatments. Cast immobilization is effective in indicated fractures, but is associated with several disadvantages such that 3D-printed orthoses (3D-Braces) have been introduced as a potentially advantageous alternative. The present study was designed to test the hypothesis that short-arm 3D-printed Polylactic Acid (PLA) orthoses would provide superior biomechanical properties when compared to plaster of Paris short-arm casts for immobilization of distal radial fractures.

Methods

Modified mannequin forearms were utilized as human models for the creation of both the circular casts and the 3D Braces. A total of five plaster cast prototypes were produced, based on a standard cylindrical plaster cast application technique used in the treatment of distal radius fractures, and another five samples were 3D printed braces. Each sample was then subjected to a three-point bend load test, using an Instron 68SC2 testing machine, and the data was collected and exported to an Excel spreadsheet and analyzed using SPSS Statistics version 26 (IBM Corp., Armonk, N.Y., USA).

Results

The 3D-Braces can withstand significantly higher forces at yield and maximum force, implying they may offer superior mechanical stability. Moreover, our findings indicated a higher strain at yield for the 3D-Braces compared to conventional plaster casts.

Conclusions

3D-printed Polylactic Acid short-arm orthoses demonstrated superior biomechanical properties when compared to plaster of Paris short-arm casts designed for immobilization of distal radial fractures. Taken together with data from previous studies, preclinical evidence suggests that PLA 3D-Braces can effectively maintain distal radius fracture alignment and stability with potential advantages over traditional casts with respect to biomechanical properties as well as post-fabrication adjustment, patient hygiene, comfort, and daily activities.

Background

Ocular injuries are common complaints in the emergency department (ED). In certain instances, a hematoma builds up behind the eyeball and can lead to increased intraocular pressure (IOP), restricting circulation and threatening vision. A lateral canthotomy can be vision-saving if performed appropriately and quickly. Unfortunately, not every physician in the ED is familiar with the procedure.

Objective

Our objective was to build a hybrid 3D-printed model to simulate lateral canthotomy, hence improving physicians’ skills in performing the procedure.

Method

Using a MakerBot 3D printer, a hemi-cranium and a sphere imitating the eyeball were printed. The model is supplemented with silicon skin and other materials. A hematoma is created using chocolate pudding. We present a low-fidelity, long-lasting hybrid model for lateral canthotomies. This model simulates the pathology, anatomy, and basic technical steps required to perform the procedure.

Conclusion

This low-fidelity simulator helps to improve procedural skills and retention through repeated practice.

3D printing, or additive manufacturing, has transformed various industries with its layer-by-layer fabrication approach. In medicine, 3D printing, or biofabrication, has seen significant advancements, particularly in the creation of patient-specific medical models and custom-made drug tablets. Bioprinting, a key aspect of biofabrication, encompasses three approaches: biomimicry, autonomous self-assembly, and microtissues, each with its unique advantages and disadvantages. This comprehensive review explores the merits and limitations of these bioprinting approaches and outlines the three main phases of the entire bioprinting process: pre-processing, processing, and post-processing. By enhancing patients’ quality of life, reducing healthcare costs, and tapping into the global medical device market, biofabrication technologies hold immense promise for the future of medicine. This literature review focuses on the applications of 3D printing technologies in creating medical devices, including bone tissues, joint tissues, 3D printed tablets, and medical models.

In this work, we developed and analyzed a biphasic calcium phosphate (BC_P) bioceramic for bone regeneration using stereolithography (SLA). The SLA method is a promising additive manufacturing (AM) technique capable of creating BCp parts with high accuracy and efficiency. However, the ceramic suspension used in SLA exhibits significantly higher viscosity and is not environmentally friendly. Therefore, adequate preparation of a suspension with low viscosity and high solid loading is essential. In this paper, we optimized the effects of surfactant doses and solid loading on the BCp slurry, and initially examined the process parameters of photocuring, debinding, and sintering. The utilization of 9 wt % Disperbyk (BYK) with a 40 vol % loading of BCp bioceramics exhibited a reasonably low viscosity of 8.9 mPa·s at a shear level of 46.5 s⁻¹. Functional and structural analyses confirmed that BCp was retained after photocuring and subsequent treatment, which were incorporated into the BYK dispersion. The 3D printed objects with different sintered temperatures, specifically at 1100 °C, 1200 °C, and 1300 °C, were further optimized. Additionally, the surface roughness, porosity, and mechanical properties of BCp green parts were systematically investigated. Most importantly, in vitro analysis of cell attachment, differentiation, and red alizarin analysis could support the application of bone regeneration.

We aimed to introduce a novel semi-automatic design approach for fabricating individualized, three-dimensional printed template dedicated to interstitial brachytherapy in vaginal tumor treatment. The central component of this concept involved the development of a cylindrical template with strategically placed tunnels to optimize applicator placement. These tunnels originated from the template's base, meticulously designed to prevent any potential overlap or interference. For precise tumor localization, we employed a method wherein the tumor's mask image was projected onto a spherical surface. Subsequently, we employed the k-means algorithm to segment the terminal points, with each cluster's center serving as the terminal point. To ensure the optimal starting point for the tunnels, we utilized the conjugate gradient method, considering the following factors: inter-starting point distance, angles between tunnels, inter-tunnel distance, and the starting point's position relative to the base of the template (inside or outside). We established a semi-automatic design paradigm for fabricating three-dimensional printed template tailored for vaginal brachytherapy. While our initial findings are promising, further comprehensive investigations are imperative to validate the clinical efficacy of this innovative concept.

Personalized medicine is the need of today's era, as one therapy does not fit all. The study aims to develop a novel patient-customized formulation using the integration of 3-D printing and Nanotechnology concepts. Valsartan (VLS) was chosen as a model drug for the study due to its poor bioavailability and dose-dependent toxicity. The Polycaprolactone (PCL)-VLS bionanoparticles (PCVBio) were formulated using a modified solvent evaporation method, inculcating the approach of Quality by Design (QbD). The amount of PCL and Polaxomer-188 (PLX) significantly influenced the PCVBio properties, which central composite design (CCD) ascertained. The results of DSC confirm the conversion of crystalline to amorphous structure. The zeta potential, PDI, and particle size ensure stability and nano size. The optimized PCVBio was further loaded into the multi-channel 3-D printed tablet (M3DPT). M3DPT was formulated by the fused deposition modeling method. The process parameters,% infill, and layer height significantly influenced the tablet's quality. The PCVbio M3DPT was able to release the VLS up to 12 h. The optimal formulation was found stable and effective. The new conjugated advanced formulation will improve the effectiveness, safety, and patient adherence. It unlocks the new research direction toward improving patients' lives.

Objective

Tendinous mallet finger injuries are normally treated conservatively by finger splinting, whereby the injured finger is immobilised in extension to allow the ruptured extensor tendon to heal. However, current splints including the Stack and Zimmer reported high failure rates of almost 50 %. Reasons are attributed to poor splint fit, skin complications and discomfort which cause non-compliance to splint regimens. To address the above mentioned issues, we designed and developed a 3D printed adjustable and customised finger splint.

Participants and interventions

The 3D printed finger splint, Zimmer and Stack splint were worn by 24 healthy volunteers on their middle fingers for 24 h.

Main outcome measures

The finger extension angle, splint fit, splint comfort and skin maceration were assessed via angle measurement and subjects’ feedback using a questionnaire.

Results

The 3D printed finger splint was capable to maintain the distal interphalangeal joint at an extended angle of 8.1° However, 70.8 % of the subjects reported that the 3D printed finger splint shifted or came off wholly during 24 h of wear. This proportion is higher compared to the Zimmer (45.8 %) and the Stack (37.5 %). While 91.7 % of the subjects were satisfied with the ease of wearing and removing the 3D printed finger splint, subjects experienced difficulty performing work and washing activities owing to the design and material.

Conclusion

Our proposed design fulfils its function of holding the fingertip in extension and improves ease of application. The design of 3D printed finger splint could be further refined to provide better splint fit and comfort, so as to achieve better treatment compliance.