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M De Gregori

Publications and source records attributed to M De Gregori.

10 recordsLinked to original sources
PubMedDate not supplied

[Shadow optic. An endoscope with optimized ligth].

Modern endoscopes use a single mid-frontal illumination source that yields an unnatural flat image. At the University of Tübingen, in collaboration with Gimmi GmbH (Tuttlingen, Germany), a new concept endoscope has been developed with an additional light source: the shadow optic. With the aid of a secondary light source along the axis of the endoscope, a shadow is obtained which gives an impression of spatial depth. The aim of the study was to assess this new endoscope objectively, focusing on the speed and safety of the surgical act. The shadow optic was used in an experimental setting by 20 probands, each of whom performed five different standardized procedures of increasing difficulty five times, with and without shadow optic in randomized sequence, making a total of 1000 experiments. The procedures consisted in spatial orientation tests, structure-surrounding maneuvers, tissue clamping, needle puncture and suturing. The evaluation criteria were the time required to perform the procedures and the number of predefined errors as determined by electronic control. In each procedure, the time needed to perform the experiments was shorter with the shadow optic, reductions of up to 18% being recorded, and the number of errors was up to 54% lower compared to the experiments conducted with the traditional endoscope. The results of the study demonstrate that, as a result of the more natural spatial view conditions, the procedures were performed faster and with greater precision when the shadow optic was used. The endoscopic imaging with the shadow optic makes for better spatial orientation and a more natural and manageable image.

Endoscopes↗
PubMedDate not supplied

[Robotic and systems technology for advanced endoscopic procedures].

The advent of endoscopic techniques changed surgery in many regards. This paper intends to describe an overview about technologies to facilitate endoscopic surgery. The systems described have been developed for the use in general surgery, but an easy application also in other fields of endoscopic surgery seems realistic. The introduction of system technology and robotic technology enables today to design a highly ergonomic solo-surgery platform. This consists of a system of devices for endoscopic surgery (HF, light source, etc...) with which the surgeon interacts directly, positioning systems for optic and instruments that the surgeon drives as the likes without assistance, and a chair to increase the comfort of the surgeon during surgery. The system of endoscopic devices named OREST (Dornier, München) designed already in 1992 opened the way to a number of systems available today that allow to the surgeon a direct control of the instrumentation. A considerable step ahead in endoscopic technology is the introduction of robotic technology to design assisting systems for solo-surgery and microsurgical instrument manipulators. Results of a number of experimental trials on combinations of different positioning devices are presented and commented. A further step in the employment of robotic technology is the design of "master-slave manipulators" to provide the surgeon with additional degrees of freedom of instrumentation. In 1996 a first prototype of an endoscopic manipulator system, named ARTEMIS, designed in cooperation with the Research Center in Karlsruhe, could be used in experimental applications. Clinical use of the system, however, will require further development of the arm mechanics and the control system. The combination with the implementation of telecommunication technology will open new frontiers, such as teleconsulting, teleassistance and telemanipulation.

Endoscopes↗