- THIS MATERIAL IS PUBLISHED AND PROTECTED BY U.S. COPYRIGHT LAW - REPRODUCTION PROHIBITED UNLESS FOR PERSONAL USE, EXCEPTING AUTHOR PERMISSION - Peter F. Kelly, D.P.M., F.A.C.F.A.S. Diplomate, American Board of Podiatric Surgery Fellow, American College of Foot and Ankle Surgeons KTP LASER APPLICATION TO HEEL SPUR SURGERY Presented in Two Sections SECTION I: THEORY AND INDICATIONS FOR KTP LASER The KTP laser is applied to both incisional foot and ankle and dermatological procedures in the author's practice. This paper relates the usefullness of the device, and significant variations in tissue interaction between this laser and others used, generally the thermal lasers, CO2 and Nd:YAG contact-tip. An improved clinical outcome when compared to the infrared lasers, CO2 or Nd:YAG contact-tip, is observed in the patient's recovery. The KTP laser is a visible light device operating at the 532 nm wavelength. Because of this wavelength the delivery system is fiberoptic. The KTP laser is used in a continuous-wave mode and may be used either in a free beam mode for dermatologic ablation or in direct tissue contact for incisional work. The 532 nm wavelength, being a brilliant green, is hazardous to the retina producing immediate irreversable damage even at low intensities. The eye protection necesary produces color shifting of the visual field of the surgeon and obscures the aiming beam. The instrument used by the author is the Laserscope KTP 532 Laser. This is a frequency doubled YAG device. The 1060 nm Nd:YAG wavelength is filtered through a potassium titanium phosphate (KTP) crystal, reducing its wavelength to 532 nm. This is then transmitted through a 600nm diameter quartz fiber which the author applies in direct contact for dissection. Immediately before surgery, the distal end of the fiber is cleaved and desheathed to produce a sharply truncated distal end having a frosted margin on its side. The application of the KTP laser to heel spur surgery is a pioneering work in our practice and in the field of Podiatry. The more specific photoablative effects of the 532 nm wavelength results in the advantage of soft tissue dissectability when compared to thermal lasers. This is more appropriate to dissscting the tissue types encountered in the heel area. A significant number of procedures (n > 25) were evaluated and compared to the Nd:YAG laser (n=50). The clinical outcome for these proceedings were evaluated concurrently. This laser is specifically photoablative at the hemoglobin absorption spectrum which greatly lessens thermal hydrolysis of the pericalcaneal adipose compared to the mid- and farinfrared lasers and provides excellent hemostasis when delineating muscles of the foot. This is a useful trait when performing surgery in a deep cavity. Quite useful to heel spur procedures is the increased visualization achieved as a result of the decrease tissue wiping, irrigation and drainage. Very low tissue carbonization also results in decreased thermal conductivity and peripheral tissue damage. The author has found the KTP laser useful for dissection of the peri- and infracalcaneal fat pad with a minimal amount of transmission through inconsequent destruction of human tissue. The author had been previously using both CO2 and Nd:YAG contact-tip for soft tissue dissection of the peri-, and infracalcaneal adipose tissue and plantar fasciotomy. With the KTP laser a much lower power density level (1,700 Watts/cm2) is required for the same degree of cutting ability than with the thermal lasers. For smooth cutting typically the CO2 free-beam and Nd:YAG contact-tip lasers require 10,000+ watts/cm2. “Section 2” describes surgical technique.