Abstract: An instrument (14) is suitable for treatment of lung tumors and other tissues and a respective apparatus (15) detects the correct positioning of instrument (14) and its two electrodes (19, 20) in a suitable target tissue by observation of two parameters (G1, G2) and particularly their time-dependent change. If the change (V1, V2) of the two parameters (G1, G2) exceeds defined thresholds (S1, S2) respectively, a contact between the instrument and the tissue to be treated and thus also the positioning of the instrument in a desired position can be derived therefrom. This remarkably increases treatment safety.

Abstract: An instrument for thermal treatment of tissue (34), particularly for electrosurgical treatment and particularly for argon plasma coagulation, is disclosed. The instrument has an instrument body (25) extending between a proximal end (27) and a distal end (28). In an end section (38) adjoining a distal end (28) the instrument body (25) comprises at least one color mark (39) in a defined color. This color corresponds to the color of a treated tissue (34) that is created, if the dosage of an energy introduction for achieving a desired depth effect in the tissue (34) has been selected correctly. Preferably the instrument is configured as probe (17), particularly as endoscope probe and has a flexible bendable instrument body (25) that can be referenced as instrument hose (26).

Abstract: An arrangement having a device for providing high-frequency voltage UApp for contact coagulation of the biological tissue. The device is equipped to operate with a high voltage that is normally not suitable for contact coagulation, but otherwise used for spark coagulation, for example, more than 400V at the beginning of the contact coagulation. During the operation of the generator the tissue impedance Z is monitored. This can occur by means of continuously measuring the voltage UApp of the flowing current IApp and the phasing ? between the voltage and the flowing current. Using both, the measuring unit continuously determines the tissue impedance Z. A minimum detector is provided to determine if an impedance minimum Zmin has passed through and if such is found, to induce the generator control to reduce the voltage UApp delivered by the device to a value that avoids spark generation as well as desiccation of the tissue.

Abstract: A device for detecting metal with sparking electrosurgical instruments. The device contains a metal detector, which decides, on the basis of the current and voltage delivered to the instrument, whether a spark originating from the instrument contacts biological tissue or a metal part. The component of the current is determined that is inconsistent with a linear equivalent circuit. The elements of the linear equivalent circuit may be determined in a regression calculation. As first decision criterion, the spark characteristic variable Frel is determined from the current. As second decision criterion, a resistance characteristic variable R is determined, which characterizes the tissue resistance. Both characteristic variables are compared with threshold values. If the tissue resistance falls below the resistance threshold value and the spark characteristic variable exceeds the spark size threshold value, a signal is generated that characterizes the activation of the spark against a metal part.

Abstract: A device for detecting metal with sparking electrosurgical instruments contains a metal detector, which decides, on the basis of the current (and the voltage) delivered to the instrument, whether a spark originating from the instrument contacts biological tissue or a metal part. This is preferably implemented by determining the component of the current that is inconsistent with a linear equivalent circuit. The elements of the linear equivalent circuit are determined previously or during the operation in a regression calculation. As first decision criterion, the spark characteristic variable Frel is determined from the current. As second decision criterion, a resistance characteristic variable R is determined, which characterizes the tissue resistance. Both characteristic variables are compared with threshold values.

Abstract: An arrangement having a device for providing high-frequency voltage UApp for contact coagulation of the biological tissue. The device is equipped to operate with a high voltage that is normally not suitable for contact coagulation, but otherwise used for spark coagulation, for example, more than 400V at the beginning of the contact coagulation. During the operation of the generator the tissue impedance Z is monitored. This can occur by means of continuously measuring the voltage UApp of the flowing current IApp and the phasing ? between the voltage and the flowing current. Using both, the measuring unit continuously determines the tissue impedance Z. A minimum detector is provided to determine if an impedance minimum Zmin has passed through and if such is found, to induce the generator control to reduce the voltage UApp delivered by the device to a value that avoids spark generation as well as desiccation of the tissue.