The authors would like to acknowledge OSF HealthCare for making this study possible, as well as Dr. Mark Plunkett&#160;for his procedural knowledge and application of skills to our final product.

<ol>
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C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Utility+of+3D+printed+cardiac+models+in+congenital+heart+disease:+a+scoping+review.">Utility of 3D printed cardiac models in congenital heart disease: a scoping review.</a> Heart. 106, 1631-1637 (2020).</li><li>Su, W., Xiao, Y., He, S., Huang, P., Deng, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-dimensional+printing+models+in+congenital+heart+disease+education+for+medical+students:+a+controlled+comparative+study.">Three-dimensional printing models in congenital heart disease education for medical students: a controlled comparative study.</a> BMC Medical Education. 18 (178), (2018).</li><li>Farooqi, K. M., Mahmood, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Innovations+in+preoperative+planning:+insights+into+another+dimension+using+3D+printing+for+cardiac+disease.">Innovations in preoperative planning: insights into another dimension using 3D printing for cardiac disease.</a> Journal of Cardiothoracic and Vascular Anesthesia. 32, 1937-1945 (2018).</li><li>Illmann, C. F., Hosking, M., Harris, K. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Utility+and+access+to+3-dimensional+printing+in+the+context+of+congenital+heart+disease:+an+international+physician+survey+study.">Utility and access to 3-dimensional printing in the context of congenital heart disease: an international physician survey study.</a> Canadian Cardiovascular Society. 2, 207-213 (2020).</li><li>Lau, I., Gupta, A., Sun, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clinical+value+of+virtual+reality+versus+3D+printing+in+congenital+heart+disease.">Clinical value of virtual reality versus 3D printing in congenital heart disease.</a> Biomolecules. 11 (884), (2021).</li><li>Birbara, N. S., Otton, J. M., Pather, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=3D+modelling+and+printing+technology+to+produce+patient-specific+3D+models.">3D modelling and printing technology to produce patient-specific 3D models.</a> Heart Lung and Circulation. 28, 302-313 (2019).</li><li>Yoo, S. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=3D+printing+in+medicine+of+congenital+heart+disease.">3D printing in medicine of congenital heart disease.</a> 3D Printing in Medicine. 2 (3), (2016).</li><li>G&#243;mez-Ciriza, G., G&#243;mez-C&#237;a, T., Rivas-Gonz&#225;lez, J. A., Velasco Forte, M. N., Valverde, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Affordable+three-dimensional+printed+heart+models.">Affordable three-dimensional printed heart models.</a> Frontiers in Cardiovascular Medicine. 8, 498 (2021).</li><li>Lau, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+and+qualitative+comparison+of+low-+and+high-cost+3D-printed+heart+models.">Quantitative and qualitative comparison of low- and high-cost 3D-printed heart models.</a> Quantitative Imaging in Medicine and Surgery. 9 (1), 107-114 (2019).</li><li>Scanlan, A. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+3D+echocardiogram+derived+3D+printed+valve+models+to+molded+models+for+simulated+repair+of+pediatric+atrioventricular+valves.">Comparison of 3D echocardiogram derived 3D printed valve models to molded models for simulated repair of pediatric atrioventricular valves.</a> Pediatric Cardiology. 39 (3), 538-547 (2019).</li><li>. Dragon skin fx-pro, Smooth-On Available from: <a target="_blank" href="https://www.smooth-on.com/products/dragon-skin-fx-pro/">https://www.smooth-on.com/products/dragon-skin-fx-pro/</a> (2021)</li><li>Tejo-Otero, A., Fenollosa-Art&#233;s, F., Buj-Corral, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mimicking+soft+living+tissues+for+3D+printed+surgical+planning+prototypes+using+different+materials.">Mimicking soft living tissues for 3D printed surgical planning prototypes using different materials.</a> Congreso Anual de la Sociedad Espa&#241;ola de Ingenier&#237;a Biom&#233;dica. , 307-310 (2019).</li><li>Lezhnev, A. A., Ryabtsev, D. V., Hamanturov, D. B., Barskiy, V. I., Yatsyk, A. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Silicone+models+of+the+aortic+root+to+plan+and+simulate+interventions.">Silicone models of the aortic root to plan and simulate interventions.</a> Interactive CardioVascular and Thoracic Surgery. 31 (2), 204-209 (2020).</li><li>Laing, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+patient-specific+cardiac+phantom+for+training+and+pre-procedure+surgical+planning.">A patient-specific cardiac phantom for training and pre-procedure surgical planning.</a> Electronic Thesis and Dissertation Repository. , 4964 (2017).</li><li>Hoashi, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Utility+of+a+super-flexible+three-dimensional+printed+heart+model+in+congenital+heart+surgery.">Utility of a super-flexible three-dimensional printed heart model in congenital heart surgery.</a> Interactive CardioVascular and Thoracic Surgery. 27, 749-755 (2018).</li><li>Mena, K. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exploration+of+time-sequential,+patient-specific+3D+heart+unlocks+clinical+understanding.">Exploration of time-sequential, patient-specific 3D heart unlocks clinical understanding.</a> 3D Printing in Medicine. 4 (1), 15 (2018).</li><li>Russo, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Advanced+three-dimensionally+engineered+simulation+model+for+aortic+valve+and+proximal+aorta+procedures.">Advanced three-dimensionally engineered simulation model for aortic valve and proximal aorta procedures.</a> Interactive CardioVascular and Thoracic Surgery. 30, 887-895 (2020).</li><li>Al Ali, A. B., Griffin, M. F., Butler, P. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-dimensional+printing+surgical+applications.">Three-dimensional printing surgical applications.</a> ePlasty. 15, 37 (2015).</li><li>. Rubber glass water-clear silicone rubber compound, Smooth-On at Available from: <a target="_blank" href="https://www.smooth-on.com/product-line/rubber-glass/">https://www.smooth-on.com/product-line/rubber-glass/</a> (2021)</li><li>Riedle, H., Molz, P., Franke, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+the+mechanical+properties+of+cardiac+tissue+for+3D+printed+surgical+models.">Determination of the mechanical properties of cardiac tissue for 3D printed surgical models.</a> IEEE-EMBS Conference on Biomedical Engineering and Science. , 171-176 (2018).</li></ol>

The authors have nothing to disclose.

Upon completion of the protocol, a patient-specific silicone cardiac model for surgical preparation should result. However, there are several critical steps that must be completed correctly for this to be achieved. A summary of the critical steps in the protocol can be seen in Supplementary File 2,&#160;as well as potential outcomes if the steps are not performed correctly. The first critical step involves the segmentation of the patient&#39;s radiologic imaging data. This step requires the acquisition of a diagnostic 3D imaging dataset. Model utility in pre-surgical planning or education is dependent on the quality of the 3D dataset. It is recommended to use an image set collected with a slice size between 0.625 mm and 2.6 mm to ensure the data set will be of adequate resolution for model production. However, all imaging parameters should be set by a clinician expert in radiology, with patient care being the priority. It should be noted that it may be possible to produce a model from an image set collected with a slice size outside the recommended values, but model resolution and quality will be negatively impacted. After images are obtained, if the segmentation is not performed correctly, it is commonly not realized until the final model is produced and cut into, resulting in a loss of time and materials. To prevent this negative outcome, it is recommended that a subject matter expert review the segmented files prior to creating the digital molds for quality control. The next critical step occurs during the creation of the digital molds. It is important to ensure that the myocardial case will be able to be assembled around the blood pool model. If the case does not close around the blood pool, it cannot be used to create the silicone model as unset silicone will continually leak out, and anatomy could be distorted. A handheld rotary sanding tool can be used to lightly remove pieces of the myocardial mold only if small adjustments are needed. If large adjustments are needed, the digital mold will need to be altered and an updated case printed. The final critical step is the pouring of the silicone. Strict adherence to material instructions is necessary when using the silicone, as failure to do so may result in silicone that cures with a tacky surface. If the surface is deemed too tacky for use by the SME, the blood pool may have to be reprinted if it cannot successfully be removed from the silicone. The silicone will have to be re-poured, resulting in a loss of time and materials. If insufficient silicone is used or the silicone leaks out of the myocardial case mold during the setting process, the resulting model will be incomplete. This failure can be remedied by mixing and pouring additional silicone into the mold. A material such as hot glue or clay can be used to seal the seams of the myocardial case mold if a small amount of silicone appears to be leaking through during the curing process.
This method of creating patient-specific silicone cardiac models can be modified to allow the creation of a model of any soft anatomical structure with patient-specific or complex inner and outer geometry. Assuming the target anatomy is segmented correctly, the remaining steps of the protocol could be followed with minimal change. While not the focus of the current work, the protocol has been applied to liver parenchyma with similar success. The utilized 3D print material can also be modified. ABS and PLA are recommended for use due to their low cost, but any dissolvable 3D print material can take the place of ABS, and any desirable 3D print material can take the place of PLA with minimal or no change to the protocol. All filament manufacturer-specified printing parameters should be followed when using other print materials. This method can further be modified by the use of a different silicone. The silicone recommended for use in this protocol has a shore hardness of 2 A, but if another shore hardness value is desirable, a different silicone can be substituted with minimal or no change to the protocol. Be sure to adhere to all manufacturing specifications and procedures when using a different silicone product.
While this protocol outlines an improved cardiac modeling procedure, it is not without limitations. The major limitation of this protocol is that while the utilized platinum cure silicone is closer to the hardness of cardiac tissue than other available materials, hardness is not the only property that plays a role in the fine-motor skill of surgical training. In particular, real cardiac tissue will demonstrate friability or tearing under force. The utilized silicone is very elastic, with an elongation at break of 763% and tensile strength of 1,986 kPa19. Porcine cardiac tissue, which is believed to be an accurate representation of human cardiac tissue, has an elongation at break of 28-66%&#160;and tensile strength of 40-59 kPa26. This difference presents a problem, as cardiac surgical fellows may perform a practice operation on a silicone model heart and gain a false sense of confidence because the model can withstand forces that real cardiac tissue cannot. This methodology also has the potential to be limited by a cardiac model with very complex geometry. As the anatomical complexity of the model increases, the protocol can compensate by increasing the number of pieces in the myocardial mold. Essentially, increasingly complex models will require increasingly complex mold designs and increased design time.
The model creation process described in this protocol is superior to many of the other available alternatives due to its ability to re-create low-cost exact anatomic replicas of surgically encountered anatomy. Cadaveric and animal tissue does allow for high fidelity simulations, but they have a much higher cost and require specific laboratory set-ups to be utilized and maintained2,6. Further, cadaveric and animal tissue models have ethical concerns, are not patient-specific, and complex CHD often must be manually manufactured by a surgeon or instructor, often leading to inaccuracies or damage to the surrounding tissues and organs. Another potential modeling technique involves the use of virtual reality. Virtual reality allows for the digital replication of patient-specific cardiac models, which is an effective tool for establishing accurate mental representations of patient anatomy and surgical plans. Additionally, some VR systems have allowed for basic simulations with the incorporation of haptic feedback. However, the available haptic feedback lacks the realism necessary to replicate necessary fine-motor skills for congenital heart surgical procedures4. 3D printing is another available method to produce patient-specific cardiac models2,24. However, the widespread implementation of high-fidelity 3D printers capable of producing multi-material, soft models are inhibited by their extremely high cost11,14,15. Low-cost 3D printers are available but can only print in materials that are much firmer than real myocardium. When one of the softest available materials for a 3D printer was used to create a model by Scanlan et al., the model was found to be firmer than real cardiac tissue17. The described material had a shore hardness between 26 A and 28 A, giving it a texture similar to a rubber band.&#160;The platinum cured silicone used in this protocol has a shore hardness of 2 A, giving it a texture similar to a gel shoe insert and much closer to the hardness of real cardiac tissues, which is 43 0020 or ~0 A. Hoashi et al. also utilized a similar method to the one described in this protocol to develop a flexible 3D printed heart model. Two molds, representing the inner and outer myocardial geometry, were 3D printed utilizing an SLA printer followed by vacuum casting a rubber-like polyurethane resin. While this method did produce a soft cardiac model, the proposed production cost of this method per model was 2,000 to 3,000 USD22. Comparatively, the total material cost of the method described in the presented protocol is less than 10 USD. Finally, a similar method was also used by Russo et al. to create silicone models of the aortic valve and proximal aorta for procedural practice. While the Russo et al. method is focused on a similar goal, their presented process aimed at replicating far simpler anatomies of the aorta or aortic valves. The protocol presented herein differentiates itself by focusing on intra-cardiac and myocardial anatomies that are smaller, more complex, and would be extremely difficult to replicate given historical methodologies. Despite this difference, the models created by Russo et al. were highly useful for simulation and training in cardiac surgery by surveyed cardiac surgeons23. Essentially, the method described in this protocol allows for the low-cost creation of complex, patient-specific congenital cardiac models with accurately represented defects and material properties more similar to real cardiac tissue than other modeling methods1,16, allowing models to be operated on with a realistic haptic fidelity.
Moving forward, this methodology could be applied to the formation of a model of any patient anatomy with complex internal and external features. Developing an alternative blood pool material that could be removed from within the silicone model in a less destructive manner or produced using a less time-consuming method would make the process more time- and cost-efficient. As a result, a new blood pool would not have to be reproduced for each subsequent molding process, leading to the scalability of the associated training. The physical properties of the silicone used to create the model could also be improved. Silicone with less elongation at break would increase the realism of the model and help to improve its value as an educational tool for cardiac surgical fellows trying to learn the necessary fine motor skills for performing these complex procedures. A group of materials currently on the market worthy of consideration to aid in this solution are silicone simulated glass materials25. These silicone materials demonstrate much less elongation at break leading to a distinct &#34;shattering&#34; upon force application in a manner similar to glass. Modulating the platinum cure silicone used in this protocol with additions of this silicone simulated glass material may allow for control of the friability characteristics of the model while still maintaining the appropriate shore hardness, improving the overall haptic fidelity. Finally, the resolution of anatomy this protocol can produce is limited by the resolution of the 3D printer utilized to generate the molds. As technology continues to improve, the resolution of anatomy that can be created with this protocol should also improve.

Nearly 1 in 100 children in the United States are born with congenital heart defects (CHD). Due to the propensity of mothers with CHDs to have children with CHDs, there is an expectation that the rate may more than double over the next seven generations1. While not each CHD is considered complex or severe, the general growth expectation indicates that there is motivation to improve the technology and procedures capable of addressing CHD treatment. As technology improves, cardiac surgeons often express a willingness to tackle more complex procedures. This willingness has led to an increased number of complex cardiac procedures, driving the need for more advanced techniques of surgical planning and education. In turn, this leaves cardiac surgeons in need of highly accurate, patient-specific models and cardiac surgical fellows in need of highly effective training methods.
Congenital cardiac surgery is one of the most technically demanding surgical disciplines due to the small size of the patients, the complexity of the cardiac abnormalities, and the rarity of some abnormalities2. In the most extreme cases, a child may be born with a single ventricle. It is not uncommon for the surgeon to take a vessel 2.0 mm in diameter and patch it with fixed pericardium to create a 1.0 cm vessel allowing a newborn to grow in this life-saving procedure - all while under the clock, as the newborn is in complete circulatory arrest. Between the normal four-chamber heart and these extreme examples are innumerable possibilities of chamber size and valve positions that constitute highly complex 3D puzzles. The role of the congenital cardiac team is to clearly delineate the unique anatomy and develop a plan to reconfigure the organic tissue into a functional heart that will allow a child to grow with the best chance at a normal life. Accurate models allow for deliberate surgical practice and repetition in an environment where errors can be forgiven and will not result in patient harm3,4. This training leads to the development of improved surgical expertise, as well as technical and judgment skills. However, limited resources and the rarity of certain cardiac conditions can make achieving the desired level of repetition and visualization nearly impossible. To help account for this resource deficiency, there has been an increase in the utilization of simulations for education2,3. Commonly utilized simulation or modeling techniques include human cadavers, animal tissues, virtual reality models (VR), and 3D printed models.
Cadaveric tissue has historically been regarded as the gold standard for surgical simulation, with animal tissue a close second. Cadavers and animal tissues can produce high fidelity simulations because they contain the anatomical structure of interest, all surrounding tissues, and allow for perfusion techniques to simulate blood flow4. Despite the benefits of tissue models, there are downsides. Embalmed tissue experiences reduced mechanical compliance, making some operations unrealistic and difficult to perform. Tissues require constant maintenance, specific facilities, are not reusable2, can be costly to obtain3, and have historically been the subject of ethical concerns. Most significantly, congenital cardiac conditions are simply not available in cadaveric samples.
VR and 3D printed models5,6,7,8,9,10 provide another option for cardiac education, simulation, and modeling to aid in the creation of pre-operative plans. These models reduce ambiguity associated with a user&#39;s varied visuo-spatial ability to interpolate 2D images as a 3D structure10,11. The virtual environment can contain surgical tools that can be manipulated and interact with models,&#160;allowing surgeons and fellows to develop hand-eye coordination, fine motor skills, and familiarity with some procedures4. Current popular 3D printing technologies, including fused deposition modeling (FDM), stereolithography (SLA), selective laser sintering (SLS), and polyjet have been found to produce models with submillimeter precision13. Both VR and 3D printed models are reusable and can be extremely detailed; models can even be generated from patient radiologic imaging data, resulting in replicas of patient anatomy. Despite the many benefits of a VR or 3D printed models, they fall short when the cost and haptic fidelity requirements of congenital heart surgery are considered. The setup of a VR environment has a high cost, and VR environments cannot provide real-world haptic feedback. While haptic fidelity technology is improving, the current gap inhibits a student&#39;s ability to become familiar with the fine-motor skills necessary to perform procedures4. Similarly, depending on the type of 3D printing technology used, the cost of 3D printing can be quite high, as the printer purchase price and print material cost must be considered11,14. A single high-fidelity cardiac model with realistic haptic feedback can be produced using a high-end printer but will cost hundreds of dollars in material alone with a printer purchase price over 100,000 USD15. A cardiac model produced using a filament with a shore hardness of 26-28 A was found to cost approximately 220 USD&#160;per model16. Alternatively, many low-cost 3D printers and technologies are available that have a printer purchase price of less than 5,000 USD. Average material prices for a cardiac model generated on a low-cost FDM printer was found to be about 3.80 USD using a material with a shore hardness of 82 A and 35 USD&#160;using a material with a shore hardness of 95 A15,16.&#160;While these machines do offer a low-cost solution, it comes at the cost of haptic fidelity.
While VR and 3D printing can allow for detailed visual and conceptual evaluation of a cardiac condition, the high price associated with producing a model for hands-on surgical simulation is often a significant barrier. One solution is the use of silicone to create a physically and texturally accurate cardiac model. Patient-specific silicone models can facilitate a deeper understanding of unique anatomy by allowing surgeons to see, feel, and even practice a procedure while experiencing realistic haptic feedback in an environment that involves minimal risk to a patient and has no consequences if the procedure is unsuccessful9. Silicone molding has been shown to be an effective method to model human anatomy that produces models with physical properties that are significantly closer to real tissue than models generated from low-cost 3D printing17.&#160;Scanlan et al., compared the properties of low-cost 3D printed to silicone molded cardiac valves to evaluate similarity to real tissue; the study found that while the physical properties of the silicone valves were not an exact replica of real tissue, the properties were far superior to the 3D printed valves17. The 3D printing material used in the study is among the softest materials available for low-cost 3D printers and possesses a shore hardness between 26 and 28 A18. The platinum cure silicone recommended for use in the protocol below has a shore hardness of 2 A&#160;which is far closer to the shore hardness of cardiac tissue, 43 on the 00 scale, or approximately 0 A19,20. This difference is significant because the silicone models allow for high-fidelity fine- motor skill training that the directly 3D printed materials do not achieve. The total material cost for the model proposed in this protocol is less than 10 USD. The proposed silicone models combine the soft tissue properties necessary for realistic haptic feedback with the versatility and precision of low-cost 3D printed models.
While the benefits of silicone may appear to make it the obvious choice for model creation, the use of silicone has been restricted by the anatomy that can be molded. Freshly mixed silicone is a liquid that requires a mold to hold it in the desired shape as it cures. Historically, silicone cardiac molds could only contain details of the outer surface of the model. Intra-cardiac details, including the entire blood pool region, would be filled with silicone and lost. Previous studies have achieved silicone models of specific areas of interest within the heart (e.g., aortic root21) or have used an extrapolatory method to simulate myocardial tissue22. This protocol is novel as it seeks to combine the use of silicone material with high-resolution anatomical, full myocardial simulation- specifically avoiding any method of extrapolation. To our knowledge, no descriptive manuscript has provided a methodology combining these aspects. The method described in this protocol introduces a technique to achieve a patient-specific cardiac model with intra-cardiac anatomic replication accurate enough for surgical preoperative practice. The method involves the creation of a myocardial mold to hold the silicone in the proper shape as it cures and an inner mold to preserve the internal, intra-cardiac details of the model and prevent the silicone from filling the blood pool region of the heart. The inner mold must then be dissolved away, leaving an entire silicone cardiac model with patient-specific anatomy on the outer and inner surfaces. Without the proposed protocol of cardiac model creation herein, no low-cost solution exists to simulate the surgical procedure with a material that mimics the actual tissue characteristics of the myocardium.

<table><tbody><tr><td>1.75 mm ABS filament</td><td>Matter Hacker</td><td>matterhackers.com/store/l/175mm-abs-filament-white-1-kg/sk/MFJ1U2CG-</td><td>Anecdotally consistent quality, budget-conscious price</td></tr><tr><td>1.75 mm PLA filament</td><td>Matter Hacker</td><td>https://www.matterhackers.com/store/l/175mm-pla-filament-white-1-kg/sk/MEEDKTKU</td><td>Anecdotally consistent quality, budget-conscious price</td></tr><tr><td>8220 12VMax High-Performance Cordless</td><td>Dremel</td><td>https://us.dremel.com/en_US/products/-/show-product/tools/8220-12vmax-high-performance-cordless</td><td>Cordless for easier access to small features in model</td></tr><tr><td>Acetone</td><td>Sunnyside</td><td>https://www.sunnysidecorp.com/product.php?p=t&amp;amp;b=s&amp;amp;n=840G5</td><td>Bulk</td></tr><tr><td>Dragon Skin Fx-Pro</td><td>Smooth-On</td><td>https://shop.smooth-on.com/dragon-skin-fx-pro</td><td>Industry-standard, characterized skin-safe</td></tr><tr><td>Ease Release 200</td><td>Smooth-On</td><td>https://shop.smooth-on.com/ease-release-200</td><td>Coating to ensure easy removal of silicone from mold</td></tr><tr><td>GORE- TEX patch</td><td>GORE</td><td>https://www.goremedical.com/products/cardiovascularpatch</td><td>Cardiovascular patch</td></tr><tr><td>ideaMaker</td><td>Raise 3D</td><td>https://www.raise3d.com/download/</td><td>&amp;nbsp;Included G-code CAD software for Raise 3D printers</td></tr><tr><td>Magics</td><td>Materilise</td><td>https://www.materialise.com/en/software/magics</td><td>Feature-rich CAD software capeable of manipulating organic surfaces</td></tr><tr><td>Mimics</td><td>Materilise</td><td>https://www.materialise.com/en/medical/mimics-innovation-suite/mimics</td><td>Feature-rich segmentation software</td></tr><tr><td>Patient DICOM data</td><td>-</td><td>-</td><td>DICOM data will typically come from a patient CT or MRI</td></tr><tr><td>Pro2 Plus</td><td>Raise 3D</td><td>https://www.raise3d.com/products/pro2-plus-3d-printer/</td><td>Anecdotallay reliable, dual extrusion FDM 3D printer</td></tr><tr><td>PRO2-100 Industrial Glue Gun</td><td>Surebonder</td><td>https://surebonder.com/collections/industrial-glue-guns/products/pro2-100-100-watt-high-temperature-professional-heavy-duty-hot-glue-gun-uses-full-size-7-16-glue-sticks</td><td>Industrial-quality hot glue gun</td></tr><tr><td>Silc Pig</td><td>Smooth-On</td><td>https://shop.smooth-on.com/silc-pig-pigments</td><td>Pigment for adding color to silicone</td></tr><tr><td>Vacuum Chamber</td><td>Smooth-On</td><td>https://shop.smooth-on.com/vacuum-chamber</td><td>Anecdotally reliable vacumm chamber for removing air bubbles from mixed silicone</td></tr></tbody></table>

creation of patient-specific silicone cardiac models with applications in pre-surgical plans and hands-on training

Three dimensional&#160;models can be a valuable tool for surgeons as they develop surgical plans and medical fellows as they learn about complex cases. In particular, 3D models can play an important role in the field of cardiology, where complex congenital heart diseases occur. While many 3D printers can provide anatomically correct and detailed models, existing 3D printing materials fail to replicate myocardial tissue properties and can be extremely costly. This protocol aims to develop a process for the creation of patient-specific models of complex congenital heart defects using a low-cost silicone that more closely matches cardiac muscle properties. With improved model fidelity, actual surgical procedural training could occur in advance of the procedure. Successful creation of cardiac models begins with the segmentation of radiologic images to generate a virtual blood pool (blood that fills the chambers of the heart) and myocardial tissue mold. The blood pool and myocardial mold are 3D printed in acrylonitrile butadiene styrene (ABS), a plastic dissolvable in acetone. The mold is assembled around the blood pool, creating a negative space simulating the myocardium. Silicone with a shore hardness of 2A is poured into the negative space and allowed to cure. The myocardial mold is removed, and the remaining silicone/blood pool model is submerged in acetone. The described process results in a physical model in which all cardiac features, including intra-cardiac defects, are represented with more realistic tissue properties and are more closely approximated than a direct 3D printing approach. The successful surgical correction of a model with a ventricular septal defect (VSD) using a GORE-TEX patch (standard surgical intervention for defect) demonstrates the utility of the method.

Radiologic imaging data from a patient with a VSD was chosen to generate a representative silicone cardiac model. Patient anatomy was segmented utilizing a CAD segmentation software to generate a digital myocardial model and a digital blood pool model (Figure 1). Manual segmentation of blood pool and myocardium with the presented protocol takes 1-3 h to complete. Upon completion of segmentation, the myocardial model was opened in CAD software for further processing. The model was aligned to a 3D box made within the program and then subtracted away using Boolean operations. This process left a negative of the myocardial model, forming a mold. This myocardial mold was trimmed to a more appropriate size, cut into segments, and modified with props for aligning the pieces (Figure 2). The creation of the case took 2-6 h. All myocardial mold pieces and the blood pool were loaded in a 3D printing slicing software, and G-Code was generated to 3D print in ABS (Figure 3). The 3D printed pieces with support material removed can be seen in Figure 4. The myocardial case pieces were vapor smoothed to enhance the surface finish of the model (Figure 5). Upon the completion of the vapor smooth process, the mold was assembled around the blood pool model, and silicone was poured. The assembly and silicone pour took one hour. After the silicone set, the cardiac model was removed from the myocardial case and submerged in acetone to dissolve the blood pool. After approximately twenty-four hours of soaking, the blood pool had dissolved. A final acetone rinse was performed, and the model was allowed to fully dry. The completed silicone cardiac model can be seen in Figure 6. To evaluate the accuracy and functionality of the silicone model, an incision was made by the CHD (congenital heart defect) expert to allow the inner anatomy to be observed. The expected VSD was present, and a GORE-TEX patch was sewn onto the model by the congenital cardiac surgeon to correct the VSD (Figure 7). In a successfully completed silicone model, all patient anatomy and defects will be present both externally and internally. A summary of the protocol can be seen in Supplementary File 1. 
<img alt="Figure 7" class="xfigimg" src="/files/ftp_upload/62805/62805fig07.jpg" /> 
Figure 7: GORE-TEX patch sewn in silicone cardiac model with VSD. Photograph of (A) surgeon&#39;s view of a patient-specific silicone cardiac model with a VSD and (B) surgeon&#39;s view of the VSD in the model closed with a GORE-TEX patch. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/62805/62805fig07large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
Supplementary File 1: Schematic of silicone heart fabrication protocol. Schematic illustration of the protocol in the fabrication of a patient-specific silicone cardiac model. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/62805/Schematic_1.psd" target="_blank">Please click here to download this File.</a>
Supplementary File 2: Summary of critical steps and potential negative outcomes. Summary of the steps critical in the development of a patient-specific silicone cardiac model and the potential negative outcomes that can result if the steps are not followed correctly. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/62805/Schematic_2.psd" target="_blank">Please click here to download this File.</a>

Watch this Scientific Journal Video about Creation of Patient-Specific Silicone Cardiac Models with Applications in Pre-surgical Plans and Hands-on Training at JoVE.com

Creation of Patient-Specific Silicone Cardiac Models with Applications in Pre-surgical Plans and Hands-on Training

Patient-specific models improve surgeon and fellow confidence when developing or learning surgical plans. Three-dimensional (3D) printers generate adequate detail for surgical preparation, but fail to replicate tissue haptic fidelity. A protocol is presented detailing the creation of patient-specific, silicone cardiac models, combining 3D printing precision with simulated silicone tissue.

Three dimensional&#160;models can be a valuable tool for surgeons as they develop surgical plans and medical fellows as they learn about complex cases. In ...

creation-patient-specific-silicone-cardiac-models-with-applications

Nanyang Technological University

Research

JoVE Journal

Bioengineering

3.4K Views.  OSF HealthCare. Complexe aangeboren hartziekten zijn een moeilijk 3D-probleem. Bestaande 3D-printtechnologieën slagen er niet in om de eigenschappen van myocardiaal weefsel nauwkeurig te repliceren. Dit protocol creëert modellen voor high-fidelity chirurgische training.Deze techniek creëert op kosteneffectieve wijze patiëntspecifieke 3D-modellen op basis van hun beeldvorming. Het modelleren van de interne en externe anatomie van hun organen stelt ons in staat om onze patiënten intiem te kennen en...

Video: Creation of Patient-Specific Silicone Cardiac Models with Applications in Pre-surgical Plans and Hands-on Training

Scaled Anatomical Model Creation of Biomedical Tomographic Imaging Data and Associated Labels for Subsequent Sub-surface Laser Engraving (SSLE) of Glass Crystals

Biomedical imaging modalities like computed tomography (CT) and magnetic resonance (MR) provide excellent platforms for collecting three-dimensional data sets of patient or specimen anatomy in clinical or preclinical settings. However, the use of a virtual, on-screen display limits the ability of these tomographic images to fully convey the anatomical information embedded within. One solution is to interface a biomedical imaging data set with 3D printing technology to generate a physical replica. Here we detail a complementary method to visualize tomographic imaging data with a hand-held model: Sub Surface Laser Engraving (SSLE) of crystal glass. SSLE offers several unique benefits including: the facile ability to include anatomical labels, as well as a scale bar; streamlined multipart assembly of complex structures in one medium; high resolution in the X, Y, and Z planes; and semi-transparent shells for visualization of internal anatomical substructures. Here we demonstrate the process of SSLE with CT data sets derived from pre-clinical and clinical sources. This protocol will serve as a powerful and inexpensive new tool with which to visualize complex anatomical structures for scientists and students in a number of educational and research settings.

Scaled Anatomical Model Creation of Biomedical Tomographic Imaging Data and Associated Labels for Subsequent Sub-surface Laser Engraving SSLE of Glass Crystals

A methodology is described herein for representing anatomical imaging data within crystals. We create scaled three-dimensional models of biomedical imaging data for use in Sub-Surface Laser Engraving (SSLE) of crystal glass. This tool offers a useful complement to computational display or three-dimensionally printed models used within clinical or educational settings.

Biomedical imaging modalities like computed tomography (CT) and magnetic resonance (MR) provide excellent platforms for collecting three-dimensional data ...

Anatomically Realistic Neonatal Heart Model for Use in Neonatal Patient Simulators

Neonatal patient simulators (NPS) are artificial patient surrogates used in the context of medical simulation training. Neonatologists and nursing staff practice clinical interventions such as chest compressions to ensure patient survival in the case of bradycardia or cardiac arrest. The simulators used currently are of low physical fidelity and therefore cannot provide qualitative insight into the procedure of chest compressions. The embedding of an anatomically realistic heart model in future simulators enables the detection of cardiac output generated during chest compressions; this can provide clinicians with an output parameter, which can deepen the understanding of the effect of the compressions in relation to the amount of blood flow generated. Before this monitoring can be achieved, an anatomically realistic heart model must be created containing: two atria, two ventricles, four heart valves, pulmonary veins and arteries, and systemic veins and arteries. This protocol describes the procedure for creating such a functional artificial neonatal heart model by utilizing a combination of magnetic resonance imaging (MRI), 3D printing, and casting in the form of cold injection molding. Using this method with flexible 3D printed inner molds in the injection molding process, an anatomically realistic heart model can be obtained.

This protocol describes a procedure for creating functional artificial neonatal heart models by utilizing a combination of magnetic resonance imaging, 3D printing, and injection molding. The purpose of these models is for integration into the next generation of neonatal patient simulators and as a tool for physiological and anatomical studies.

Neonatal patient simulators (NPS) are artificial patient surrogates used in the context of medical simulation training. Neonatologists and nursing staff ...

In Silico Clinical Trials for Cardiovascular Disease

The SILICOFCM project mainly aims to develop a computational platform for in silico clinical trials of familial cardiomyopathies (FCMs). The unique characteristic of the platform is the integration of patient-specific biological, genetic, and clinical imaging data. The platform allows the testing and optimization of medical treatment to maximize positive therapeutic outcomes. Thus, adverse effects and drug interactions can be avoided, sudden cardiac death can be prevented, and the time between the commencement of drug treatment and the desired result can be shortened. This article presents a parametric model of the left ventricle automatically generated from patient-specific ultrasound images by applying an electromechanical model of the heart. Drug effects were prescribed through specific boundary conditions for inlet and outlet flow, ECG measurements, and calcium function for heart muscle properties. Genetic data from patients were incorporated through the material property of the ventricle wall. Apical view analysis involves segmenting the left ventricle using a previously trained U-net framework and calculating the bordering rectangle based on the length of the left ventricle in the diastolic and systolic cycle. M-mode view analysis includes bordering of the characteristic areas of the left ventricle in the M-mode view. After extracting the dimensions of the left ventricle, a finite elements mesh was generated based on mesh options, and a finite element analysis simulation was run with user-provided inlet and outlet velocities. Users can directly visualize on the platform various simulation results such as pressure-volume, pressure-strain, and myocardial work-time diagrams, as well as animations of different fields such as displacements, pressures, velocity, and shear stresses.

In Silico Clinical Trials for Cardiovascular Disease

This protocol demonstrates the workflow of the SILICOFCM platform for automatically generating a parametric model of the left ventricle from patient-specific ultrasound images by applying a multi-scale electromechanical model of the heart. This platform enables in silico clinical trials intended to reduce real clinical trials and maximize positive therapeutic outcomes.

The SILICOFCM project mainly aims to develop a computational platform for in silico clinical trials of familial cardiomyopathies (FCMs). The unique ...

3D Planning and Printing of Patient Specific Implants for Reconstruction of Bony Defects

We are in the midst of the 3D era in most aspects of life, and especially in medicine. The surgical discipline is one of the major players in the medical field using the constantly developing 3D planning and printing capabilities. Computer-assisted design (CAD) and computer assisted manufacturing (CAM) are used to describe the 3D planning and manufacturing of the product. The planning and manufacturing of 3D surgical guides and reconstruction implants is performed almost exclusively by engineers. As technology advances and software interfaces become more user-friendly, it raises a question regarding the possibility of transferring the planning and manufacturing to the clinician. The reasons for such a shift are clear: the surgeon has the idea of what he wants to design, and he also knows what is feasible and could be used in the operating room. It allows him to be prepared for any scenario/unexpected results during the operation and allows the surgeon to be creative and express his new ideas using the CAD software. The purpose of this method is to provide clinicians with the ability to create their own surgical guides and reconstruction implants. In this manuscript, a detailed protocol will provide a simple method for segmentation using segmentation software and implant planning using a 3D design software. Following the segmentation and stl file production using segmentation software, the clinician could create a simple patient specific reconstruction plate or a more complex plate with a cradle for bone graft positioning. Surgical guides can be created for accurate resection, hole preparation for proper reconstruction plate positioning or for bone graft harvesting and re-contouring. A case of lower jaw reconstruction following plate fracture and nonunion healing of a trauma sustained injury is detailed.

This protocol describes the use of 3D planning and printing for reconstruction of bony defects. We use segmentation tools to create 3D models followed by 3D design software to create patient specific implants for reconstruction purposes concomitant to ablative surgery or as a second stage.

We are in the midst of the 3D era in most aspects of life, and especially in medicine. The surgical discipline is one of the major players in the medical ...

Medicine

Treatment of Facial Deformities using 3D Planning and Printing of Patient-Specific Implants

Technological advancements in surgical planning and patient-specific implants are constantly evolving. One can either adopt the technology to achieve better results, even in the less experienced hand, or continue without it. As technology develops and becomes more user-friendly, we believe it is time to allow the surgeon the option to plan his/her operations and create his/her own patient-specific surgical guides and fixation plates allowing him full control over the process. We present here a protocol for 3D planning of the operation followed by 3D planning and printing of surgical guides and patient-specific fixation implants. During this process we use two commercial computer-assisted design (CAD) software. We also use a fused deposition&#160;modeling printer for the surgical guides and a selective laser sintering printer for the titanium patient-specific fixation implants. The process includes computed tomography (CT) imaging acquisition, 3D segmentation of the skull and facial bones from the CT, 3D planning of the operations, 3D planning of patient-specific fixation implant according to the final position of the bones, 3D planning of surgical guides for performing an accurate osteotomy and preparing the bone for the fixation plates, and 3D printing of the surgical guides and the patient-specific fixation plates. The advantages of the method include full control over the surgery, planned osteotomies and fixation plates, significant reduction in price, reduction in operation duration, superior performance and highly accurate results. Limitations include the need to master the CAD programs.

As technology develops and becomes more user-friendly, planning of operations and patient-specific surgical guides and fixation plates should be performed by the surgeon. We present a protocol for 3D planning of orthognathic skeletal movements and 3D planning and printing of patient-specific fixation plates and surgical guides.

Technological advancements in surgical planning and patient-specific implants are constantly evolving. One can either adopt the technology to achieve ...

Development and Evaluation of 3D-Printed Cardiovascular Phantoms for Interventional Planning and Training

Catheter-based interventions are standard treatment options for cardiovascular pathologies. Therefore, patient-specific models could help training physicians&#39; wire-skills as well as improving planning of interventional procedures. The aim of this study was to develop a manufacturing process of patient-specific 3D-printed models for cardiovascular interventions.
To create a 3D-printed elastic phantom, different 3D-printing materials were compared to porcine biological tissues (i.e., aortic tissue) in terms of mechanical characteristics. A fitting material was selected based on comparative tensile tests and specific material thicknesses were defined. Anonymized contrast-enhanced CT-datasets were collected retrospectively. Patient-specific volumetric models were extracted from these datasets and subsequently 3D-printed. A pulsatile flow loop was constructed to simulate the intraluminal blood flow during interventions. Models&#39; suitability for clinical imaging was assessed by x-ray imaging, CT, 4D-MRI and (Doppler) ultrasonography. Contrast medium was used to enhance visibility in x-ray-based imaging. Different catheterization techniques were applied to evaluate the 3D-printed phantoms in physicians&#39; training as well as for pre-interventional therapy planning.
Printed models showed a high printing resolution (~30 &#181;m) and mechanical properties of the chosen material were comparable to physiological biomechanics. Physical and digital models showed high anatomical accuracy when compared to the underlying radiological dataset. Printed models were suitable for ultrasonic imaging as well as standard x-rays. Doppler ultrasonography and 4D-MRI displayed flow patterns and landmark characteristics (i.e., turbulence, wall shear stress) matching native data. In a catheter-based laboratory setting, patient-specific phantoms were easy to catheterize. Therapy planning and training of interventional procedures on challenging anatomies (e.g., congenital heart disease (CHD)) was possible.
Flexible patient-specific cardiovascular phantoms were 3D-printed, and the application of common clinical imaging techniques was possible. This new process is ideal as a training tool for catheter-based (electrophysiological) interventions and can be used in patient-specific therapy planning.

Here we present development of a mock circulation setup for multimodal therapy evaluation, pre-interventional planning, and physician-training on cardiovascular anatomies. With the application of patient-specific tomographic scans, this setup is ideal for therapeutic approaches, training, and education in individualized medicine.

Catheter-based interventions are standard treatment options for cardiovascular pathologies. Therefore, patient-specific models could help training ...

Creation of a High-Fidelity, Low-Cost, Intraosseous Line Placement Task Trainer via 3D Printing

The description of procedural task trainers includes their use as a training tool to hone technical skills through repetition and rehearsal of procedures in a safe environment before ultimately performing the procedure on a patient. Many procedural task trainers available to date suffer from several drawbacks, including unrealistic anatomy and the tendency to develop user-created &#39;landmarks&#39; after the trainer tissue undergoes repeated manipulations, potentially leading to inappropriate psychomotor skill development. To ameliorate these drawbacks, a process was created to produce a high-fidelity procedural task trainer, created from anatomy obtained from computed tomography (CT) scans, that utilize ubiquitous three-dimensional (3D) printing technology and off-the-shelf commodity supplies.
This method includes creating a 3D printed tissue mold capturing the tissue structure surrounding the skeletal element of interest to encase the bony skeletal structure suspended within the tissue, which is also 3D printed. A tissue medium mixture, which approximates tissue in both high-fidelity geometry and tissue density, is then poured into a mold and allowed to set. After a task trainer has been used to practice a procedure, such as intraosseous line placement, the tissue media, molds, and bones are reclaimable and may be reused to create a fresh task trainer, free of puncture sites and manipulation defects, for use in subsequent training sessions.

We describe a procedure to process computed tomography (CT) scans into high-fidelity, reclaimable, and low-cost procedural task trainers. The CT scan identification processes, export, segmentation, modeling, and 3D printing are all described, along with the issues and lessons learned in the process.

The description of procedural task trainers includes their use as a training tool to hone technical skills through repetition and rehearsal of procedures ...

Digital Hybrid Model Preparation for Virtual Planning of Reconstructive Dentoalveolar Surgical Procedures

Virtual, hybrid three-dimensional (3D) model acquisition is presented in this article, utilizing the sequence of radiographic image segmentation, spatial registration, and free-form surface modeling. Firstly cone-beam computed tomography datasets were reconstructed with a semi-automatic segmentation method. Alveolar bone and teeth are separated into different segments, allowing 3D morphology, and localization of periodontal intrabony defects to be assessed. The severity, extent, and morphology of acute and chronic alveolar ridge defects are validated concerning adjacent teeth. On virtual complex tissue models, positions of dental implants can be planned in 3D. Utilizing spatial registration of IOS and CBCT data and subsequent free-form surface modeling, realistic 3D hybrid models can be acquired, visualizing alveolar bone, teeth, and soft tissues. With the superimposition of IOS and CBCT soft tissue, thickness above the edentulous ridge can be assessed about the underlying bone dimensions; therefore, flap design and surgical flap management can be determined, and occasional complications may be avoided.

A workflow for creating three-dimensional (3D) virtual hybrid models has been designed based on cone-beam computed tomography dataset and intraoral optical scans utilizing radiographic image segmentation methods and free-form surface modeling. Digital models are used for the virtual planning of reconstructive dentoalveolar surgical procedures.

Virtual, hybrid three-dimensional (3D) model acquisition is presented in this article, utilizing the sequence of radiographic image segmentation, spatial ...

A Personalized 3D-Printed Model for Preoperative Evaluation in Thyroid Surgery

The anatomic structure of the surgical area of thyroid cancer is complex. It is very important to comprehensively and carefully evaluate the tumor location and its relation with the capsule, trachea, esophagus, nerves, and blood vessels before operation. This paper introduces an innovative 3D-printed model establishment method based on computerized tomography (CT) DICOM images. We established a personalized 3D-printed model of the cervical thyroid surgery field for each patient who needed thyroid surgery to help clinicians evaluate the key points and difficulties of the surgery and select the operation methods of key parts as a basis. The results showed that this model is conducive to preoperative discussion and the formulation of operation strategies. In particular, as a result of the clear display of the recurrent laryngeal nerve and parathyroid gland locations in the thyroid operation field, injury to them can be avoided during surgery, the difficulty of thyroid surgery reduced, and the incidence of postoperative hypoparathyroidism and complications related to recurrent laryngeal nerve injury reduced too. Moreover, this 3D-printed model is intuitive and aids communication for the signing of informed consent by patients before surgery.

Here, a new method of establishing a personalized 3D-printed model for preoperative evaluation of thyroid surgery is proposed. It is conducive to preoperative discussion, reducing the difficulty of thyroid surgery.

The anatomic structure of the surgical area of thyroid cancer is complex. It is very important to comprehensively and carefully evaluate the tumor ...

3D Printing Model of a Patient's Specific Lumbar Vertebra

Selective dorsal rhizotomy (SDR) is a difficult, risky, and sophisticated operation, in which a laminectomy should not only expose an adequate surgical field of view but also protect the patient&#39;s spinal nerves from injury. Digital models play an important role in the pre-and intra-operation of SDR, because they can not only make doctors more familiar with the anatomical structure of the surgical site, but also provide precise surgical navigation coordinates for the manipulator. This study aims to create a 3D digital model of a patient-specific lumbar vertebra that can be used for planning, surgical navigation, and training of the SDR operation. The 3D printing model is also manufactured for more effective work during these processes.
Traditional orthopedic digital models rely almost entirely on computed tomography (CT) data, which is less sensitive to soft tissues. Fusion of the bone structure from CT and the neural structure from magnetic resonance imaging (MRI) is the key element for the model reconstruction in this study. The patient&#39;s specific 3D digital model is reconstructed for the real appearance of the surgical area and shows the accurate measurement of inter-structural distances and regional segmentation, which can effectively help in the preoperative planning and training of SDR. The transparent bone structure material of the 3D-printed model allows surgeons to clearly distinguish the relative relationship between the spinal nerve and the vertebral plate of the operated segment, enhancing their anatomical understanding and spatial sense of the structure. The advantages of the individualized 3D digital model and its accurate relationship between spinal nerve and bone structures make this method a good choice for preoperative planning of SDR surgery.

This study aims to create a 3D-printed model of a patient-specific lumbar vertebra, which contains both the vertebra and spinal nerve models fused from high-resolution computed tomography (HRCT) and MRI-Dixon data.

Selective dorsal rhizotomy (SDR) is a difficult, risky, and sophisticated operation, in which a laminectomy should not only expose an adequate surgical ...

Creation of Patient-Specific Silicone Cardiac Models with Applications in Pre-surgical Plans and Hands-on Training

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