Dutch researchers develop tools to simplify keyhole surgery

Mar 23 2006

Endoscopic surgery brings many advantages for patients but is very difficult for the surgeon.

Working at the Academic Medical Centre in Amsterdam, Joris Jaspers has developed two instruments which make this approach easier and also cheaper than with existing surgical robotics. Jaspers is awarded his doctorate on Wednesday 22 March at Delft University of Technology.

Endoscopic operations (or keyhole surgery) are much less stressful for the patient and give a better cosmetic result than 'open' surgery. But on the other hand, it is very difficult for the surgeon to carry out keyhole surgery. This is due to the disruption of hand-eye coordination, as the surgeon has to operate via a 2D image on a monitor. Moreover, the video camera has to be operated by an assistant and the work must be done using long and rigid instruments that provide little freedom of movement. The existing robot systems that have been developed to solve the aforementioned problems are complex, expensive and do not provide the required (force) feedback to the surgeon.

The aim of Joris Jaspers' research project was to develop simple mechanical alternatives to these complex robotic systems, and also to test them. Jaspers is a doctoral student at the department of Mechanical Engineering of Delft University of Technology, but the greater part of his work is conducted at the Academic Medical Centre (AMC) in Amsterdam, where in recent years he has developed and evaluated two instruments in collaboration with surgeons.

The first instrument is a camera and instrument holder. Using this mechanical arm the surgeon can operate the camera himself (with one hand), thus allowing him to conduct the operation by himself without a (camera) assistant. A test showed that this enabled 'solo surgery' and that it even brought advantages in comparison to surgery using an assistant.

The second instrument developed by Jaspers is a mechanical manipulator for operating the various instruments used in keyhole surgery. Two mechanical arms, provided with artificial 'wrist joints' for extra freedom of movement, transmit the surgeon's hand movements exactly onto the instruments. This is achieved using rods, cables and parallelogram constructions.

This mechanical manipulator thus fulfils a similar function to the surgical robot systems, but in a simpler and cheaper manner. In a test carried out with experienced medical students, the manipulator was compared to the existing (rigid) instruments. This study showed that far fewer actions were needed when using the manipulator and that fewer mistakes were made than with the existing instruments.

Jaspers will now further develop this mechanical manipulator, supported by funding from the Ministry of Economic Affairs and in collaboration with engineering firms. Work on his camera and instrument holder is now complete and it will be commercially available in the near future.