Radiofrequency ablation

The radiofrequency ablation ( syn.: radiofrequency ablation, RFA ) is a medical method for local destruction of tissue. In radiofrequency ablation, an applicator is inserted into the tissue and produces here a Thermonekrose ( heat destruction) by the heat from the high frequency current.

The radiofrequency ablation is used in various medical therapies, such as the treatment of cardiac arrhythmias, or destruction of liver metastases.

Operation

The available devices on the market have to produce different design with the aim of a possible large and thereby controlled necrosis depending on the manufacturer. RITA / Angiodynamics uses thin Aufspreizelektroden and a 460 kHz generator that provides 250 watts. Radionics uses rod-shaped, cooled electrodes and a pulsed 480 -kHz waves at max. 200 watts of power. Advantages and disadvantages of the systems are holding up the scale. Approximately 2.4-2.8 cm wide areas of tissue can be destroyed per electrode position. This approximately 1 ampere flowing stream. After 12-20 minutes, the area lying at the electrode tissue charring formation of gas; thus rise to electrical resistance and impedance, and the energy transfer stops. For the attitude control of the probes used ultrasonography or computed tomography.

Application in cardiology

When radiofrequency ablation in the treatment of cardiac arrhythmias of origin of the arrhythmia to be treated as part of an Electrophysiological examination (EPU ) is visited with a catheter and heated on the supply of electricity. This results in a scar, which has no electrical activity more.

Application for metastases treatment

In the treatment of liver metastases (tumor metastases in the liver), the RF ablation is increasingly being used as an alternative to liver part removal. Advantages of radiofrequency ablation are:

  • Minimally invasive application are possible: The treatment can often by puncture through the skin (that is, without an operation ) can be applied
  • Repeatability: Even after prior liver surgery or repeated occurrence of metastasis radiofrequency ablation can be applied
  • Fabric -saving: due to anatomical conditions must often a part of the liver are removed, which is substantially greater than the metastasis in an operation of liver metastases. In the RF ablation only the metastasis itself is destroyed with a safety margin of 10 mm.

Currently no larger prospective randomized study exists comparing the RF ablation with resection of liver metastases. The direct detection of the cancer therapeutic safety of the method is not so provided. However, the data available so far suggest an equivalence of these forms of treatment regarding the cancer therapeutic safety.

Coblation

Coblation of controlled ablation ( manufacturer name, engl about "controlled ablation " ) is a rule developed by the Californian company Arthrocare 2003 variant, in which only temperatures up to 70 ° C can be achieved. It is mainly used by ear, nose and throat doctors, for example, for tonsillectomy. The previously presented studies show that it is superior to other methods, however, do not.

Literature and References

  • Higgins H, Berger DL. RFA for liver tumors: does it really work? Oncologist. 2006 Jul-Aug, 11 ( 7) :801 -8. Review. PMID 16880239
  • Guan YS, Liu Y. Interventional treatments for hepatocellular carcinoma. Hepatobiliary Pancreat Dis Int. November 2006, 5 ​​( 4) :495 -500. Review. PMID 17085331
Electrical impedance Catheter ablation Metastatic liver disease Otolaryngology Digital Object Identifier Cryoablation
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