Radiosurgery uses high-frequency current in a variety of dermatologic applications. The generators used in radiosurgery (e.g., Ellman Surgitron, Ellman International, Hewlett, NY) transform 60 cycles per second wall electricity into currents that exceed 3 million cycles per second. The high-frequency currents operate in the realm of AM radio signals (hence, the name radiosurgery). Radiosurgery is used in cosmetic surgery procedures because the high-frequency currents permit cutting through tissue without dissipating heat into surrounding tissues, thereby limiting injury and scarring.
Ablation or thermal tissue destruction also is possible with radiosurgery units. By changing the radiosurgical waveforms, additional heat can be created to increase tissue destruction. Older electrosurgery units were limited to ablative currents because of their lower current frequencies (e.g., Hyfrecator, ConMed Corporation, Utica, NY). Spark-gap or tissue fulgurating procedures are not considered cosmetic, but they are effective in destroying warts or other growths in non-cosmetically important body areas. A small, metal ball electrode can be used for ablation of superficial skin lesions. Flat electrodes are used for matricectomy destruction during surgery for ingrown toenails. Ablation of unwanted veins and telangiectasias can be performed with fine wires inserted into the veins.
A major application for dermal radiosurgery is the feathering of wound edges after shave excision of lesions (see Chapter 11). After a lesion has been removed by the shave technique, a scooped-out skin defect usually exists. If this defect is allowed to heal without alteration, a circular, depressed scar often results. The shadow produced by the edges of the depression creates an inferior cosmetic result and draws the attention of an observer's eye. The final cosmetic outcome can be improved by smoothing or feathering the wound edges. Feathering blends the final light color of the scar into the surrounding skin and eliminates any sharp wound edges that can cast shadows on vertical skin surfaces.
Feathering is performed only using a high-frequency cutting current. The technique uses superficial passes of an electrosurgical wire loop over the skin surface. The technique can be used to smooth any irregularity to the skin surface. Because the technique is designed to affect only the skin surface, scarring that results from deeper dermal injury is prevented.
Administer local anesthesia for most excisional, destructive, or feathering radiosurgical procedures. To illustrate the technique of feathering, first perform a shave excision (see Chapter 11) such as the radiosurgical technique illustrated here. When using a dermal loop to remove a superficial lesion, the lesion can be grasped and elevated using Adson forceps. Elevate the lesion upward through the loop, activate the electrode, and move the electrode horizontally to free the lesion from the underlying tissue. Use a blended (i.e., cutting and coagulation) or cutting-current (i.e., initial machine setting of 3, approximately 30 watts) for the excision.
(1) When using a dermal loop to remove a superficial lesion, the lesion can be grasped and elevated using Adson forceps.
PITFALL: With greater upward pull on a lesion, the loop electrode passes deeper in the dermis, and greater scarring results. To avoid excessive upward pull, many physicians shave off lesions without using forceps to elevate the lesion.
PITFALL: Do not use nondermal loop electrodes for excision of skin lesions. Use of larger loop electrodes, such as cervical loops, produces larger defects. Use small, short-shafted dermal loops for better control of the depth of excision and feathering.
After a shave excision, a circular, crater-like defect often exists (Figure 2A.) To perform feathering, the machine setting is set to cutting current only, and the power setting usually starts at 1½ to 2 (15 to 20 watts). Stretch the skin surrounding the treatment site using the fingers on the nondominant hand. Pass the loop over the skin surface with short, back-and-forth motions, eliminating sharp edges and blending the wound edges into surrounding skin (Figure 2B.) The final wound is smoothed and produces superior cosmetic results (Figure 2C.)
(2) Radiosurgical feathering.
PITFALL: Novice physicians often produce additional scoop defects when initially performing radiosurgical feathering. To prevent additional scooping defects, stretch the skin around the treatment site tightly, and pass the loop in the air just above the treatment site. Gently lower the loop to the skin surface, and do not drag the loop on the surface during feathering to avoid additional defects and deeper scars.
Perform ablation of superficial skin lesions using coagulation current with a power setting of 3 to 4½ (30 to 45 watts). Hold the electrode directly onto the tissue surface to produce a burn (i.e., thermal injury).
(3) During ablation, hold the electrode directly onto the tissue surface to produce a thermal injury.
Hold the electrode just above the tissue surface, and a spark will travel from the electrode tip to the surface of the skin. The electrode can be gently “bounced” on the skin surface to facilitate this spark-gap or fulguration technique. Fulguration produces an eschar (i.e., dry, burn scab) that limits the depth of thermal injury.
(4) Fulguration technique.
PITFALL: The higher the current setting, the greater the heat applied to the target tissue. Use lower current settings to avoid excessive tissue burns and scarring.
Radiosurgery effectively removes unwanted veins. The machine is set on coagulation current, with a setting of 2 to 3½ (20 to 35 watts). Insert the fine tungsten wire into the vein by puncturing the wire through stretched skin. Apply a brief (half-second) burst of cautery current. Local anesthesia usually is not administered before telangiectasia ablation, because the fluid distorts the local tissues and vessel. Many patients tolerate well the brief application of low-voltage current; oral diazepam or superficially applied anesthetic creams also can be used.
(5) Insert the fine tungsten wire into the vein by puncturing the wire through stretched skin.
No additional reimbursement is provided for feathering. The CPT codes for shave excision (11300–11313) are applied (see Chapter 11). The main reasons for performing feathering are the superior cosmetic and functional outcomes. Destruction codes (17000–17111) can be applied for ablation procedures (see Chapter 19).
INSTRUMENT AND MATERIALS ORDERING
Radiosurgical generators; electrodes for dermatologic, gynecologic, plastic surgery, or ear, nose, and throat uses; smoke evacuators; and other accessories are available from Ellman International, 1135 Railroad Avenue, Hewlett, NY 11557-2316 (phone: 800-835-2316;http://www.ellman.com) and from Wallach Surgical Devices, 235 Edison Road, Orange, CT 06477 (phone: 203-799-2002;http://www.wallachsd.com). An anesthesia tray that can be used for this procedure is listed in Appendix G. Skin preparation recommendations appear in Appendix H.
Acland KM, Calonje E, Seed PT, et al. A clinical and histologic comparison of electrosurgical and carbon dioxide laser peels. J Am Acad Dermatol 2001;44:492–496.
Bader RS, Scarborough DA. Surgical pearl: intralesional electrodesiccation of sebaceous hyperplasia. J Am Acad Dermatol 2000;42:127–128.
Bridenstine JB. Use of ultra-high frequency electrosurgery (radiosurgery) for cosmetic surgical procedures [Editorial]. Dermatol Surg1998;24:397–400.
Hainer BL. Electrosurgery for cutaneous lesions. Am Fam Physician 1991;445 (Suppl): 81S–90S.
Hainer BL. Fundamentals of electrosurgery. J Am Board Fam Pract 1991;4:419–426.
Harris DR, Noodleman R. Using a low current radiosurgical unit to obliterate facial telangiectasias. J Dermatol Surg Oncol 1991;17:382–384.
Hettinger DF, Valinsky MS, Nuccio G, et al. Nail matrixectomies using radio wave technique. J Am Podiatr Med Assoc 1991;81:317–321.
Pollack SV. Electrosurgery of the skin. New York: Churchill Livingstone, 1991.
Sebben JE. Electrodes for high-frequency electrosurgery. J Dermatol Surg Oncol 1989;15: 805–810.
Wright VC. Contemporary electrosurgery: physics for physicians [Editorial]. J Fam Pract 1994; 39: 119–122.
Wyre HW, Stolar R. Extirpation of warts by a loop electrode and cutting current. J Dermatol Surg Oncol 1977;3:520–522.
Zuber TJ. Dermal electrosurgical shave excision. Am Fam Physician 2002;65:1883–1886, 1889–1890, 1895, 1899–900.
Zuber TJ. Office procedures. The Academy collection–quick reference guides for family physicians. Baltimore: Williams & Wilkins, 1999.