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3D-Printing-Assisted EADs for Preventing VUR through DJ Stents
computational simulation was conducted for forward References
and backward urine flows. Consequently, the difference
in the cross-sectional pressure fields of the penta-shaped 1. Pengfei S, Min J, Jie Y, et al., 2011, Use of Ureteral Stent
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PLA mold and die were tailored to create four different https://doi.org/10.1016/j.juro.2011.05.073
umbrella shapes with flexible and biocompatible Ecoflex.
Among the fabricated devices, the penta-shaped EAD 2. Hübner WA, Plas EG, Trigo-Rocha F, et al., 1993, Drainage
showed the best anti-reflux performance compared to and Reflux Characteristics of Antireflux Ureteral Double-J
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significant changes depending on the number of EADs https://doi.org/10.1148/radiographics.22.5.g02se081005
attached to the DJ stent. Thus, a single EAD sufficed 4. Irani J, Siquier J, Pirès C, et al., 1999, Symptom Characteristics
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to demonstrate the safety, mechanical durability, and https://doi.org/10.1097/00042307-200205000-00007
chemical stability of the device in urine for at least 6. Sarier M, Demir M, Duman I, et al., 2017, Evaluation of
4 weeks. Although in vivo and parametric studies on the Ureteral Stent Colonization in Live-Donor Renal Transplant
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to enhance the rectification performance, the findings https://doi.org/10.1016/j.transproceed.2017.01.004
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manufacture various medical devices with flexibility, 7. Sarier M, Seyman D, Tekin S, et al., 2017, Comparision of
biocompatibility, mechanical durability, and chemical Ureteral Stent Colonization Between Deceased and Live Donor
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https://doi.org/10.1016/j.transproceed.2017.09.028
Funding 8. Kim HH, Kim KW, Choi YH, et al., 2020, Numerical

This work was supported by the National Research Analysis of Urine Flow with Multiple Sizes of Double-J
Foundation of Korea (NRF), funded by the Ministry of Stents. Appl Sci, 10:4291.
Science and ICT of the Republic of Korea (No. NRF- https://doi.org/10.3390/app10124291
2021R1C1C1010836).
9. Seymour H, Patel U, 2000, Ureteric Stenting-current Status.
Conflict of interest Semin Intervent Radiol, 17:351–65.
The authors declare that there is no conflict of interest. https://doi.org/10.1055/s-2000-13148
10. Damiano R, Oliva A, Esposito C, et al., 2002, Early and Late
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106 International Journal of Bioprinting (2022)–Volume 8, Issue 2