Lasers create custom medical devices, and make suturing easier
By Ben Coxworth
March 1, 2011
If you remember the MASH episode where Hawkeye and BJ got the Korean fix-it guy to build them a one-of-a-kind vein clamp, then you will understand the importance of custom-designed surgical tools – surgery is definitely not a field in which people should just make do with the next-best thing. Unfortunately, the production of some types of instruments can be quite involved, meaning they can't always be created quickly or cheaply. At this month's MEDTEC Europe trade show, however, researchers from Germany's Fraunhofer Institute for Manufacturing Technology and Advanced Materials will be demonstrating new technology that uses a laser melting process to easily create pretty much any surgical instrument imaginable ... or so they claim.
Fraunhofer's technique uses metal powder – cobalt-chromium steel or titanium – as its building material. An extremely thin laser beam is used to melt this powder down, building it from the bottom up into the desired object one layer at a time, not unlike a 3D printer. There are said to be no restrictions on the shape or interior structure of the instrument, allowing it to even contain features such as curved channels. Previously, such features would usually need to be cast, or welded into place.
All that is required before production can begin is a three-dimensional computer model – no molds or production tools are necessary.
Likely due to the layered nature of the finished products, radio-frequency identification (RFID) chips enclosed inside of them can still transmit and receive. Previously, small holes had to be left in instruments containing such chips, otherwise they couldn't be read. By using RFID-equipped tools, surgical staff would be able to keep track of information such as their location, total numbers, state of cleanliness, and date of manufacture.
Also at MEDTEC, a team from the Fraunhofer Institute for Production Technology will be presenting a new laser-welding instrument that is said to take the guesswork out of the internal suturing process in endoscopic surgery.
Currently, surgeons must manually tie off such sutures, setting the tension of each knot to what they hope is not too tight or too loose – mistakes in either direction can have serious consequences. Fraunhofer's new device semi-automates the process. A loop of polypropylene suturing material is threaded through the wound, then clipped with a predefined tension to a polypropylene sleeve adjacent to the wound. A laser then welds the suture to the sleeve. This process is continued along the length of the wound, until it is closed.
Not only are wounds closed in this fashion said to heal faster, but the suturing process itself is also quicker. The sleeve remains inside the patient after the procedure is completed, although the researchers hope that in the future, it could be manufactured using reabsorbent materials.
Preclinical studies of the device are scheduled to begin later this year in Germany.