One of the most successful methods for the treatment of malignant and benign tumors is the thermal denaturation of tissue induced by absorbed light from a laser. Our LITT fiber products are emitting a spherical light profile along the entire length of up to 35 mm. A special spherical laser power meter was designed to measure the integral laser power. An exact coagulation zone can be obtained by varying laser power and application time. For faster treatment a beam splitter is built to apply up to four fibers with one laser unit. This allows the treatment of larger or metastatic tumors. In combination with a stable laser system a maximum of patients safety is obtained and the physical strain is reduced.
Fiber optics are used in medicine in power transmission for therapeutic use as well as in signal transmission for diagnostics. Fibers are the key component of the applicators which find a wide and varied use. Applicators with optical fibers are part of the standard equipment used with the various continuous and pulsed medical laser systems. Recently, optical fiber applicators for the Er:YAG, CO, and CO2 laser have become available. A combination of therapeutic and diagnostic fibers promises, for example in lithotripsy and angioplasty, not only to improve the safety level, but also to ensure the accuracy of the dosage and the precision of the laser energy applied. For the design of commercial fiber optic components a practical definition of the engineering damage threshold including a reasonable safety factor is given. With respect to this engineering damage threshold an overview of existing fiber technology with respect to the fields of application is presented and two examples of feedback systems to increase safety are discussed.