Falls or accidents can lead to a fracture of the orbital floor, especially in older people. These fractures are not only painful, but can also restrict vision. In many cases, surgery is medically necessary. In the past, an implant was inserted via the lower eyelid. This procedure often leads to complications and, in the worst case, can damage the optic nerve during insertion.
Avoid risks during surgery: Access via the maxillary sinus
Prof Dr Thomas Kühnel from Regensburg University Hospital developed a minimally invasive treatment method several years ago. The procedure is carried out via the nose and the maxillary sinus, which lies under the floor of the eye socket. However, a suitable implant and implantation system were previously lacking.
Dr Moritz Burger developed this as part of a project funded by the Bavarian Research Foundation. ‘Prof Dr Kühnel initially let me watch operations,’ says Burger. ‘This allowed me to gain my own impression of the problems that exist and the requirements that an implant has to fulfil - for the patients, but also for the doctors as users.’
From concept to design: Dr Moritz Burger developed the prototype
Burger began the detailed work in the medical devices laboratory at OTH Regensburg. He analysed numerous clinical CT scans to define the requirements for the implant and the implantation system: What is the maximum size of the implantation system? Where does the fracture occur? What must the implant be able to do? A skull from the 3D printer reproduced the anatomy in detail and made it possible to adapt the design accordingly.
An important prerequisite: the implant must be inserted through an approx. 12 millimetre opening and then adapt to the fracture site. Together with industrial partner Gerresheimer Regensburg GmbH in Wackersdorf, Burger produced a prototype suitable for series production.
In this prototype, the implant is first rolled up and placed on the tip of the implantation system. An actuating lever for the surgeon unfolds the implant through the mechanism in the tip of the implantation system, expands into the maxillary sinus and pushes the fracture back into its original shape. If necessary, the implant can be modelled with millimetre precision.
Dr Moritz Burger received the BioPark Innovation Award 2024 for his doctoral thesis.
From research to practice: what's next?
Around 1,500 fractures of the orbital floor are operated on every year in Germany using the conventional, complication-prone method. However, it will be some time before the new implantation system can be used.
Prof Dr Thomas Schratzenstaller is head of the Medical Devices Laboratory and was Moritz Burger's doctoral supervisor. ‘We would like to bring the new implantation system onto the market together with industrial partners and thus replace the previous method. However, approval can take up to five years.’
Burger, Schratzenstaller and Kühnel applied for a patent for their joint work at the beginning of their doctoral thesis.
