Endonasal Laser Surgery With a New Laser Fiber Guidance Instrument

Laser procedures are common in surgery of the head and neck and in various other medical fields. The laser is used as an adjunct or substitute for conventional surgical treatment. In the management of chronic turbinate hypertrophy, laser surgery is a promising procedure, 1-10 but it is awkward to manipulate the laser fiber in combination with rhinoscopic equipment and suction devices. In light of the smoke and toxic pyrolysis agents generated by the laser, 11 the disadvantage of inaccurate positioning, and the need for a controlled overview of the treatment area, we have developed a new device and treatment technique for tissue removal in nasal turbinate surgery. In developing a new laser fiber guidance instrument, we sought to bend the distal fiber tip over a wide-angle range out of the optical axis of the fiber, rotating the entire system coaxial to the optical axis by 360°. In addition, smoke and pyrolysis agents needed to be extracted to obtain a clear view and prevent exposure to toxic agents, 11 and the system needed to be easy to operate with one hand, freeing the other hand to guide the endoscope. Initially, after manufacturing a prototype version of the device, we measured light losses attributable to the bending of the flexible laser light fiber. The power required to extract smoke and the possibility of inducing cracks as a result of fiber bending were also determined. After fulfilling all criteria, the system was tested clinically by performing laser treatment of inferior nasal turbinates with patients under local anesthesia. At present, 30 patients have been treated by means of a diode laser emitting light at λ = 940 nm using a soft-bending, plastic-clad, silica fiber (400-μm core diameter). The output power was set at 8 to 10 W continuous wave (applied energy: 600–1,000 J/turbinate). Another 20 patients underwent Ho:YAG laser treatment (λ = 2,080 nm; 0.8–1 J/pulse; repetition rate, 4 to 8 Hz; applied energy, 200–600 J/turbinate) using a hard-bending, low OH, quartz fiber (400-μm core diameter). 3 The flat end bare fiber was introduced through the instrumentation channel at 0° bending position. The polished fiber tip exited the distal part of the device for 1 to 2 mm, while the fiber was fixed by means of a set screw at the proximal part. Afterwards, the system was positioned relative to the treatment area by means of site-specific bending and rotation of the laser fiber guidance instrument under direct vision using an endoscope. This was followed by three to five laser light applications by moving the system from the posterior to the anterior part of the inferior turbinate. 3 Although the laser fiber guidance instrument shown in Figure 1 has an appearance and handling similar to conventional ENT instrumentation, the function differs. Its distal end (Fig. 2) can be bent in a range from −5° up to 45°, either continuously or incrementally (in 5° steps). The light loss at 45° of deflection was measured at less than 10% for the wavelength range tested (several between λ = 630 nm and λ = 2,100 nm). Introduction of the laser fiber through the working channel did not affect the polished bare fiber tip and kept it completely intact, because it did not have to pass any curvature. The suctioning and smoke extraction capabilities revealed an optimum view of the operating field. Therefore toxic pyrolysis products were extracted for the safety of the patient as well as the physician. 11 Prototype of the laser fiber guidance instrument manufactured by Karl Storz (Tuttlingen, Germany). The distal part of the laser fiber guidance instrument can be bent in a range from −5° (top) up to 45° (bottom) to the optical axes of the fiber. Exhaust holes provide a clear view, free of smoke and toxic agents. Figure 3 demonstrates the instrument during operation of a nasal turbinate hypertrophy. While the fiber exits the device for about 2 mm, the laser beam is directed toward the operation field by bending the distal part of the instrument. Because of suctioning, a clear view can be achieved and the extent of the coagulation and vaporization area can be observed. Laser fiber guidance system during operation of a nasal turbinate hypertrophy. The laser procedure itself becomes less traumatic and more comfortable using this device. The clinical results of laser treatment showed that about 75% of the patients reported improved nasal breathing 15 months after laser treatment. This benefit could be realized by comparing the size of a turbinate before and 8 weeks after laser treatment, as shown in Figure 4. The subjective judgment of the patient could be confirmed by rhinomanometry, acoustic rhinometry, and allergy testing. 3 Combining the ablation and coagulation effects of the laser tissue interaction results in a response with significant tissue reduction within 2 to 3 weeks. The patient appreciates the good treatment comfort and short treatment time of this new device, and the physician welcomes its ergometric construction, optimized handling, and increased efficacy. Comparison of a nasal turbinate before and after laser treatment. A. Chronically swollen turbinate before laser treatment. B. Turbinate 8 weeks after laser treatment. This new laser fiber guidance instrument is a timesaving and cost-effective tool for surgeons who perform endonasal laser surgery in an ambulatory setting. It does not require postoperative nasal packing and can be used in combination with nearly all types of lasers emitting different wavelengths or emitting light either in a continuous wave or a pulsed manner, if the laser light transmission system fits through the instrumentation channel. Optimization of the device's geometric dimensions will make it more efficient and feasible in pediatric endonasal surgery. Other laser treatments, such as for Osler's disease, synechia, chronic sinusitis (bullous concha), and choanal atresia, were also performed using this laser fiber guidance instrument. In combination with an improvement in minimally invasive and less traumatic treatment technologies, the newly developed laser fiber guidance instrument will become more versatile for use in other treatment fields. The authors would like to thank Karl Storz (Tuttlingen, Germany), for helpful and quick realization of the clinical prototype of the laser fiber guidance instrument, as well as Dornier-Medizintechnik, Germering, Germany, for support of both lasers used.