Zusammenfassung
Fragestellung: Die interstitielle Laserapplikation wird zur Gewebeablation an unterschiedlichen
Organen klinisch erfolgreich eingesetzt. Nachteil der Methodik sind hohe Kosten durch
eine begrenzte Haltbarkeit der Sonden. Ziel der Studie war es zu überprüfen, ob unter
Vermeidung von Karbonisationen an der Lasersonde eine Minderung der Transmission nach
Applikation hoher Laserenergien auftreten.
Material und Methodik: Am Modell der In-Vitro-Niere wurden Arbeitssonden mit Quarzglaskappe eingestochen.
Nach Applikation von jeweils 9900 Joule Laserenergie (Nd: YAG-Laser) wurde die Transmission
der Lasersonde bestimmt und mit einer Referenzsonde (ohne Quarzglaskappe) verglichen.
Ergebnisse: Durch die Applikation von Laserenergien traten bis hin zu Gesamtenergien von 49500
Joule keine Minderung der Transmission auf (Transmissionsquotient 1,0 - 1,07). Wurden
hohe Leistungen über längere Zeit appliziert, die zu Karbonisationen führten, fiel
die Transmission deutlich ab.
Schlussfolgerung: Die Haltbarkeit von Lasersonden kann durch Vermeidung von Karbonisationseffekten
gesteigert werden. Ein kostensparender Mehrfacheinsatz der Sonden wird dadurch ermöglicht.
Summary
Purpose: During the last few remaining years, interstitial thermotherapy with laser applications
has gained momentum in therapeutical usage. One problem however, is the limited durability
of the expensive probes. The aim of this study was to determine whether avoidance
of carbonisation of the laser probes leads to a reduction in transmission following
application of higher laser energies.
Material and Method: Nd:YAG-Laser was used for application to a pig's kidney in vitro probes with quartz
caps. After 9900 Joules, transmission was measured and compared to a reference probe
without a quartz cap.
Results: By avoiding carbonisation effects, we could apply 49 500 Joules without a decrease
in transmission (transmission quotient 1.02 - 1.07). When carbonisation occurred,
however, the doses transmitted decreased significantly.
Conclusions: This procedure becomes cost effective when the probes are sterilised and re-used
and carbonisation effects avoided.
Schlüsselwörter:
Interstitielle Thermotherapie - Lasersonden - Haltbarkeit - Karbonisation
Key words:
Laser surgery - Interstitial coagulation - Multiple fiber application - Ex-vivo study
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Priv.-Doz. Dr. med. K. U. Köhrmann
Urologische Klinik, Klinikum Mannheim gGmbH
Theodor-Kutzer-Ufer 1 - 3
68135 Mannheim
Telefon: 0621/383-2235
Fax: 0621/383-3822
eMail: kai.uwe.koehrmann@uro.ma.uni-heidelberg.de
