Intraoperative Diagnostic and Interventional Magnetic Resonance Imaging in Neurosurgery
1997; Lippincott Williams & Wilkins; Volume: 41; Issue: 4 Linguagem: Inglês
10.1097/00006123-199710000-00068
ISSN1524-4040
AutoresRené L. Bernays, Edward R. Laws,
Tópico(s)Advanced Neuroimaging Techniques and Applications
ResumoTo the Editor: We have read the article by Tronnier et al.(1) with great interest. The following comments show the controversial perception of this new field. As a team working with the 0.5-tesla Signa SP (General Electric) open interventional MR imaging (MRI) system since 1995, we are convinced that this system will have a major impact on neurosurgery. The General Electric system, in contrast to the system used by Tronnier et al. in Heidelberg, Germany, allows intraoperative imaging during surgery. Current and future options include real-time neuronavigation, thermosensitive imaging, and real-time functional imaging. Neurosurgical procedures in the General Electric open interventional MRI system are dependent on MR-compatible instrumentation. One of several unsolved problems concerning instrumentation for use in the open interventional MRI system is bipolar cautery. The two systems that are currently commercially available have been tested in Zurich, Germany. Because of the reduced electrical conductivity of titanium alloys used for bipolar forceps, we experienced either insufficient cauterization or troublesome carbonization producing sticking of the tips of the forceps. This makes continuous cleaning necessary and considerably prolongs the surgical procedure. Furthermore, MRI during cauterization is impossible. In search of a solution to this problem, we tested a new contact laser provided by Surgical Laser Technologies(Montgomeryville, PA), with Wavelength Conversion surface treatment in an ablative case of therapy refractory epilepsy at the neurosurgery department of the University of Virginia. The round probe for coagulation was very effective and was not associated with sticking of the probe or charring, and the hemostatic effect was excellent. The general purpose laser scalpel has good cutting characteristics. However, during this case, several small arteries were opened by the scalpel and the laser energy had to be increased to 15 W to provide a satisfactory hemostatic effect. Further development will include a laser forceps and a flat tip for cutting and coagulating. Because this laser system is MRI-compatible, we think it will contribute significantly to the exciting new field of open MRI neurosurgery. Rene L. Bernays Zurich, Switzerland Edward R. Laws, Jr. Charlottesville, Virginia
Referência(s)