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Involuntary female infertility represents a sensitive issue, which is frequently caused by an impaired patency of the Fallopian tube. Current treatment options, such as in vitro fertilisation (IVF) or tubal reconstruction, are related to high costs or surgical risks. Therefore, a need for an alternative highly safe and effective minimally invasive therapy option is assumed. The current work presents a proof-of-concept for a novel microstent in combination with a delivery system for treatment of proximal Fallopian tube occlusions. For this purpose, a microstent prototype was implanted into a porcine Fallopian tube ex vivo using the presented delivery system. The results of the procedure were analyzed using a micro-computed tomography (μ-CT). Based on the μ-CT imaging, critical parameters of the microstent, such as radial patency, were assessed. The microstent implantation leads to an increased opening area of the Fallopian tube. Additionally, the microstent does not impair the anatomical shape of the tube epithelium and adapts well to the anatomical path. In further studies, the functionality of the Fallopian tube will be examined after microstent implantation in vivo.

Proximal occlusion of the Fallopian tube is one of the most common causes of female infertility. Due to the occlusion, the passage of the fallopian tubes is no longer given. Basically, there are two options for patients affected by this condition: cost-intensive in vitro fertilization (IVF) or surgery. The pregnancy rates of approximately 50% achieved with current treatment options are not satisfying. In this work, we present a Finite Element Analysis (FEA) model of a previously reported optimized microstent design for minimally invasive therapy of proximal tubal occlusion. Based on experimental investigations, the material model was set up and the simulation was validated. Comparison of the mechanical performance as an application related critical load case was in a good agreement. In this work, the proof of concept for the FEA model and the material model were carried out. In the future, the simulation will be used for further load cases such as the investigation of the bending stiffness and radial force and for the design optimization.

Glaucoma represents a chronic eye disease that becomes increasingly prevalent worldwide. Therapies are commonly based on the reduction of intraocular pressure (IOP). Implant devices for micro-invasive glaucoma surgery (MIGS) represent a promising therapy option in refractory cases but suffer from limitations in long term efficacy or from dislocation associated complications. Our approach of an innovative drug-eluting glaucoma microstent for MIGS was presented previously. Within the current work we developed concepts and prototypes of a mechanism for the fixation of our glaucoma microstent in the region of the corneal limbus. A tripod and a haptics design of the fixation mechanism were developed and manufactured. Semifinished products were tested with regard to dimensional stability and mechanical properties according to the standard ANSI Z80.27-2014. Considering the mechanical properties of ocular target tissues, a gelatin based in vitro model for the measurement of microstent retention force was developed. Retention force testing of microstent prototypes in vitro resulted in a proof of concept for the fixation mechanism. Future studies will focus on the use of smaller fixation fibers, for example commercially available suture material, and on an overall miniaturization of the fixation mechanism enabling the use of our applicator device with a 22G x 1½” cannula.

The European Parliament and the European Council on May 26, 2017 decided to introduce the new regulatory framework for medical devices. The transitional period of the so called Medical Device Regulation (EU 2017/745, MDR) should end on May 26, 2020. Currently the European Commission is working on a proposal to postpone the application for one year to relieve pressure from all stakeholders allowing them to fully focus on priorities related to the coronavirus crisis. From this date or most likely from May 26, 2021, manufacturers must present a CE-certificate according to the new MDR requirements not only for novel medical devices, but also for approved medical devices which are already on the market. The MDR will significantly complicate the process of bringing medical devices into market due to the increased requirements for the CE-certification process, particularly concerning increased documentation effort. This involves a risk for the translation of innovative products due to an overload of the overall system (manufacturers, Notified Bodies, experts) and might lead to shrinkage of the product range of existing products. Thankfully, adaption of transitional periods, special regulations, extensions of deadlines and most probably postponement of the MDR application date will ensure that there will be no gaps in medical supply that endanger patients. Establishing and keeping the relevant regulatory expertise up to date and devoting the necessary financial, time and human resources that is the biggest immediate challenge the medium-sized medical technology sector is facing in the near future. The current article, written about one month before the initially expected end of the first transition period on May 26, 2020, summarized the main aspects of the current state of MDR implementation with respect to regulatory novelties, the current legal basis in Germany, transition periods and changes in the requirements of CE-certification relevant technical documentation. Furthermore, challenges for existing and innovative medical devices were shortly discussed using a new stent based therapy of the proximal Fallopian tubal stenosis and transcatheter aortic valve implantation as two examples.