gms | German Medical Science

56. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e. V. (DGNC)
3èmes journées françaises de Neurochirurgie (SFNC)

Deutsche Gesellschaft für Neurochirurgie e. V.
Société Française de Neurochirurgie

07. bis 11.05.2005, Strasbourg

Electrophysical characteristics of lumbar disc tissue

Elektrophysikalische Eigenschaften von lumbalem Bandscheibengewebe

Meeting Abstract

  • corresponding author D. Freudenstein - Klinik für Neurochirurgie, Eberhard Karls Universität, Tübingen
  • K. Brinks - Klinik für Neurochirurgie, Eberhard Karls Universität, Tübingen
  • C. Staudinger - Klinik für Neurochirurgie, Eberhard Karls Universität, Tübingen
  • M. Tatagiba - Klinik für Neurochirurgie, Eberhard Karls Universität, Tübingen
  • F. Duffner - Klinik für Neurochirurgie, Eberhard Karls Universität, Tübingen

Deutsche Gesellschaft für Neurochirurgie. Société Française de Neurochirurgie. 56. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e.V. (DGNC), 3èmes journées françaises de Neurochirurgie (SFNC). Strasbourg, 07.-11.05.2005. Düsseldorf, Köln: German Medical Science; 2005. Doc10.05.-12.01

Die elektronische Version dieses Artikels ist vollständig und ist verfügbar unter: http://www.egms.de/de/meetings/dgnc2005/05dgnc0145.shtml

Veröffentlicht: 4. Mai 2005

© 2005 Freudenstein 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

Text

Objective

Several different minimally invasive procedures for treating lumbar disc prolapse have been developed in the past few years. Considering an incidence of 5% of lumbar disc prolapse among the population per year, and also considering the increasing application of percutaneous and minimally invasive methods, it is necessary to discuss their basics. For this reason we evaluate the biophysical characteristics of lumbar disc tissue in an animal cadaver study.

Methods

Thirty lumbar spines of German Land Pigs were used for the presented study. Physiological saline was defined as reference for measuring the impedance of the discs. Thus we could attain the demanded independence from the impedance probe used. To diminish systematic error the discs were packed in watertight film and heated up to 37°C in temperate water bath before the HF coagulation. The thermal measurements were performed via display of the temperatures by a infra-red camera. The discs were coagulated in the nucleus at various durations, and the volumes were measured. Documentation was performed via a digital camera and in a magnetic resonance scanner (Magnetom open, Siemens, Erlangen, Germany).

Results

In the whole vertebral disc the impedance decreased as the temperature rose. The decrease in resistance was about the same in all of the three measure areas. The zone of devitalization (area with a minimum temperature of 43°C) had a mean diameter of 15 mm, while the temperature gradually approximated a limit value. The volume measurements before and after coagulation proved a constant decrease of volume up to 270 sec, when a reduction of disc volume down to 50% could be achieved. These findings could be reproduced in the magnetic resonance unit, where a reduction of disc volume down to 50% was achieved after 270 sec of coagulation as well.

Conclusions

A gauge curve for our setting is described. With this gauge curve the shrinking of the lumbar discs could be optimized. Additionally, an explanation for incoherent results of other methods using high frequency energy to lumbar discs was obtained.