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Resorbable Ligation Device Elicits Successful Preliminary Results

Poly-Med, Inc. (PMI) is thrilled to share the success of the LigaTie®, a device designed and developed by Resorbable Devices AB in Uppsala, Sweden that utilizes one of Poly-Med’s Glycoprene® polymers. The LigaTie® device was developed by Dr. Odd Viking Höglund (http://bit.ly/innovator-LigaTie) and addresses challenges associated with ligation during surgical procedures. The device is utilized to restrict blood flow, prevent blood loss, and prevent air leaks, when used on lungs or airways. PMI supports Resorbable Devices AB in the material development of a novel, flexible, fast degrading, absorbable polymer that has been able to meet the demanding specifications of the LigaTie® device. The current product scope initially focuses on veterinary applications, and Resorbable Devices AB has seen great success with clinical results to date.

The LigaTie® has been successful in the following veterinary procedures: in vivo canine neutering, ligation of ovarian pedicles 1, 2 and spermatic cords,3 ex vivo cholecystectomies (removal of gallbladder) to seal the cystic duct,4 ex vivo sealing of lung tissue at lung biopsies,5 in vivo lung lobectomy in dogs with lung cancer,6 and a video-assisted thoracoscopic lung lobectomy (removal of lung lobe).7 The LigaTie® design is based on the concept of a cable tie, and the design allows for ligation of a single artery. The device is a flexible, unidirectional, self-locking, loop device produced from one of PMI’s Glycoprene® absorbable materials .

Permanent surgical sutures, and other non-absorbable devices (i.e., clips, cable ties, staples), may be used for ligation applications, but threaten to cause negative tissue responses, such as infection, inflammation, or chronic granulomas/scar tissue formation. On the other hand, the LigaTie® exhibits the following benefits due to the novel design and material choice: good tissue grip, easy and minimally invasive placement, which results in a reduction in surgery time (compared to suture ligation), standardized and secure locking mechanism, minimal inflammatory reactions, and acceptable responses for the mechanical performance-to-resorption profile. The preliminary results for the LigaTie® device are extremely promising and truly offer an innovative product for tissue ligation to prevent hemorrhage or leakage of air.

PMI is excited to support companies working to address challenges in the biomedical engineering and biotechnology fields. With PMI’s vertically integrated structure, they are capable of assisting clients take their ideas from exploration and investigation to final manufacturing and market, through in-house material development, analytical testing, product development, and project management. Connect with PMI today to hear more about our material offerings and design, development, and analytical capabilities! If you are interested in hearing more about how Poly- Med can help advance your idea or product, contact us today!

1 Höglund, O., et al. (2013). 27(8), pp.961-6. doi: 10.1177/0885328211431018.
2 Da Mota Costa, M., et al. (2016). BMC Res Notes, 9(245), pp. 1-6. doi: 10.1186/s13104-016-2042-2.
3 Höglund, O., et al. (2014). BMC Res Notes, 7(825), pp. 1-7. doi: 10.1186/1756-0500-7-825.
4 Tepper, S., et al. (2017). Can J Vet Res, 81(3), pp. 223-7. PMID: 28725113.
5 Nylund, A. et al. (Accepted). Vet Surg. Evaluation of a resorbable self-locking ligation device for performing peripheral lung biopsies in a caprine cadaveric model.
6 Ishigaki et al. (2017). Presentation at ACVS Surgery Summit. doi 10.1111/vsu.12710.
7 Guedes, R., et al. (2018). Surg Innov., 25(2), pp. 158-164. doi: 10.1177/1553350617751293. Link to video.

The PMI Perspective: Independent Evaluation of Poly-Med’s Bioresorbable Medical Grade 3D Printing Filaments

Poly-Med has recently been in collaboration with Queensland University of Technology to promote research of our unique, bioresorbable medical grade 3D printing filaments. The latest publication, authored by Mina Mohseni, Professor Dietmar Hutmacher, and Dr. Nathan Castro, highlights performance of these filaments in fused filament fabrication (FFF) additive manufactured (AM) tissue scaffolding. Specifically, this research sought to characterize material properties and evaluate potential use in both hard and soft tissue engineering applications.

As Mohseni et al. notes, additive manufacturing has established itself as an advantageous method for fabrication of unique and physiologically relevant structures to support tissue growth. Equally important in selecting the correct scaffolding structure, choosing the appropriate material is also vital for successful tissue ingrowth. Currently, Poly-Med offers four medical grade filaments for 3D printing: Lactoprene® 100M, Max-Prene® 955, Dioxaprene® 100M, and Caproprene™ 100M. The bioresorbable nature of these filaments make them ideal candidates for tissue scaffolding applications and use in regenerative medicine.

Through extensive physiochemical analysis of these four filaments, Mohseni et al. concludes that all filaments are viable options for tissue scaffolding, with each material having unique properties to fit a range of soft and hard tissue applications. For example, it was noted that Dioxaprene® 100M exhibits softness and flexibility, making it an ideal choice for soft tissue engineering. Caproprene™ 100M displays similar mechanical properties as those of Dioxaprene® 100M, however Caproprene™ 100M strength and mass loss occurs over a much longer time frame. Thus, while Dioxaprene® 100M and Caproprene™ 100M are both soft tissue-oriented, either can be selected depending on the desired degradation timeline.

For hard tissue applications, materials with a higher stiffness are often preferred. To this effect, Poly-Med offers Max-Prene® 955 and Lactoprene® 100M, which both exhibit an elastic modulus suitable for hard tissue regeneration, with values in the range of 63-89 MPa. In fact, elastic modulus and other mechanical properties of these materials can be tuned by adjusting scaffold pore size, % infill, which Mohseni et al. further details in the article.

Poly-Med offers four unique bioresorbable filaments for 3D printing, each with its own niche and range of potential applications. Mohseni et al. has provided an extensive review of the physiochemical properties of these filaments that can help guide any device manufacturer in the right direction when determining which material is best for a given product. As always, feel free to contact Poly-Med for assistance with any aspect of additive manufacturing – we are here to be a creative partner as you bring your solution to market. Contact us for more information regarding our bioresorbable 3D printing filaments.

To see the original Queensland University of Technology evaluation: