gms | German Medical Science

55. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e. V. (DGNC)
1. Joint Meeting mit der Ungarischen Gesellschaft für Neurochirurgie

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

25. bis 28.04.2004, Köln

Image-guided neurosurgery with an electromagnetic device – Clinical evaluation and phantom tests

Neuronavigation mit einem elektromagnetischen System - klinische und Phantom-Untersuchungen

Meeting Abstract

  • corresponding author Arya Nabavi - Klinik für Neurochirurgie, Universitätsklinikum Schleswig-Holstein, Campus Kiel, Kiel
  • R. Werner - Klinik für Neurochirurgie, Universitätsklinikum Schleswig-Holstein, Campus Kiel, Kiel
  • R. Buhl - Klinik für Neurochirurgie, Universitätsklinikum Schleswig-Holstein, Campus Kiel, Kiel
  • S. Wolff - Klinik für Neurochirurgie, Universitätsklinikum Schleswig-Holstein, Campus Kiel, Kiel
  • M. Pinsker - Klinik für Neurochirurgie, Universitätsklinikum Schleswig-Holstein, Campus Kiel, Kiel
  • H. M. Mehdorn - Klinik für Neurochirurgie, Universitätsklinikum Schleswig-Holstein, Campus Kiel, Kiel

Deutsche Gesellschaft für Neurochirurgie. Ungarische Gesellschaft für Neurochirurgie. 55. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e.V. (DGNC), 1. Joint Meeting mit der Ungarischen Gesellschaft für Neurochirurgie. Köln, 25.-28.04.2004. Düsseldorf, Köln: German Medical Science; 2004. DocP 08.80

Die elektronische Version dieses Artikels ist vollständig und ist verfügbar unter: http://www.egms.de/de/meetings/dgnc2004/04dgnc0363.shtml

Veröffentlicht: 23. April 2004

© 2004 Nabavi et al.
Dieser Artikel ist ein Open Access-Artikel und steht unter den Creative Commons Lizenzbedingungen (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.de). Er darf vervielf&aauml;ltigt, verbreitet und &oauml;ffentlich zug&aauml;nglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.


Gliederung

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Objective

In conventional image-guided systems, a dynamic reference frame (drf) tracks the patient´s head. This detects head motion. Although there have been major improvements in this technology, this drf has to be visible (line of sight). Electromagnetic navigation systems provide head and instrument tracking without this constraint. We have evaluated one system in 11 clinical cases and in a phantom study.

Methods

The navigation system uses a magnetic transducer to form a magnetic field around the imaging volume. Instruments and pointers, which are connected to the navigation system by cables, can be detected by this transducer. It detects the field distortion specific to each device, and calculates the tip-position of the device. The instruments are interchangeable, the system automatically recognizes subsequent instruments, after initial calibration. The transducer can be beneath the sterile drapes, outside the line of sight. Clinical cases included supra- and infratentorial tumors, as well as skull base lesions. The phantom study was conducted to evaluate the effects of metallic bodies on the magnetic field.

Results

The set-up time for this navigation system is slightly less than for other systems. The accuracy is comparable to other systems, and showed a range of 1-3 mm application accuracy. The use of interchangeable instruments is superior to other systems. The biggest achievement was the absence of the line of sight problem. In the phantom study we found major field distortions caused by larger metallic bodies. The Budde-Halo, which we use routinely during surgeries rendered the navigation unreliable. This problem was solved by using a ceramic Budde-Halo. Nevertheless, when the microscope was introduced too close to the transducer, major distortions were detected. This could only be resolved by removing the microscope.

Conclusions

This technology holds major promise for neurosurgical use. There is no line of sight issue, the magnetic transducer can be more freely located, even beneath the drapes. Major issues remain in the field distortion caused by large metallic bodies.