Why CO2 laser performs well in soft tissue surgeries

    By Peter Vitruk, PhD, MInstP, CPhys For The Education Center
    Originally Published In Veterinary Practice News, February 2019 – Download as a PDF

    Laser surgery is in high demand by pet owners. Thousands of veterinarians around the globe have transitioned to CO2 laser surgery, as it has numerous clinical benefits for patients and brings additional revenues to the practice.

    co2 laser surgery 1 absorption coefficient

    Figure 1: Spectra of absorption coefficient, 1/cm, at histologically relevant concentrations of water, hemoglobin (Hb) and oxyhemoglobin (HbO2) in subepithelial oral soft tissue. Note: Thermal Relaxation Time, TRT, msec; short-pulse Ablation Threshold Fluence, Eth, J/cm2; and short-pulse Photo-Thermal Coagulation Depth, H, mm. B is gingival blood vessel diameter. Logarithmic scales are in use.

    The clinical advantages of the soft-tissue CO2 laser are explained by the unique absorption coefficient of its wavelength.[1-4] The advantages include:

    • Char-free and bloodless surgery. Combining the CO2 laser wavelength and SuperPulse settings allows for approximately 1,000 times more photo-thermal cutting efficiency than do diodes and approximately 10 times more coagulating efficiency than do erbium lasers (Figure 1).
    • Controlled, repeatable and reproducible speed of tissue removal.
    • The close match between the coagulation depth of the SuperPulse CO2 laser and the blood capillary diameters,[3,4] as illustrated in Figure 1. This affords the clinician improved visibility of the surgical field, thus facilitating more accurate tissue removal.[3-5]
    • Well-controlled depth of incision—unlike with hot-tip cutting diodes—and with a dynamic range from micrometers to millimeters. It is proportional to laser power and inversely proportional to the laser beam spot size and the surgeon’s hand speed.[4]
    • The focal spot diameter of the laser beam determines the quality of the laser cut.
    • The risk of postoperative edema is minimized due to the intraoperative closure of lymphatic vessels on the margins of the CO2 laser incision.[4,5]
    • Reduced postoperative pain and discomfort have been reported with CO2 laser surgery.4,5
    • CO2 laser surgical wounds, unlike scalpel ones, are characterized by the minimal post-surgery activation of myofibroblasts and diminished wound contraction and scarring.[4,5]
    co2 laser surgery 2 tip distance

    Figure 2: Tip-to-tissue distance is maintained at 1 to 3 millimeters to achieve a designated focused beam spot size of 250 μm.

    Notable Differences

    Practical surgical lasers, such as Luxar-Accuvet and Aesculight, feature these distinct specifications:

    • Air-cooled, all-metal tube, CO2 laser resonator with a 45,000-hour lifetime.
    • Air-cooled, low-voltage transistor-driven radio frequency power supplies.
    • Flexible fiber CO2 laser beam delivery system and an onboard calibration for flexible fiber.
    • Disposable-free, pen-size, sterile laser handpieces with multiple laser beam spot sizes and shapes. For cutting, the laser handpiece is maintained 1 to 3 millimeters away from the tissue (Figure 2) and moved at the speed of a few millimeters per second. To quickly switch from cutting to coagulation, the laser beam can be defocused by moving the handpiece away from the tissue.
    • On-board laser power meter and diagnostics tools assure the accuracy of laser settings for long-term ownership.
    • Built-in library of more than 100 clinical cases with settings, photos, videos and pre- and post-op recommendations from veterinarians.
    • Customizable pre-sets.
    • Original and extended warranties from U.S.-based manufacturing facilities.
    • International laser safety compliance with regulations from the U.S. Food and Drug Administration’s Center for Devices and Radiological Health.

    Summary

    Clinicians opt for the CO2 laser because its unique wavelength is optimal for cutting or coagulating the water-rich soft tissue. The laser pulsing settings ensure fast cutting with minimal collateral tissue damage.

    Precise control over the depth of incision, less traumatic surgery, excellent hemostatic ability and enhanced healing with minimal scarring make the SuperPulse CO2 laser a safe and efficient alternative to a scalpel.[l]

    Peter Vitruk is a founder of LightScalpel-Aesculight LLC. He is a member of the Institute of Physics and the founder of the American Laser Study Club. He may be reached at 866-589-2722 or [email protected]

    References

      1. Jacques SL. “Optical Properties of Biological Tissues: A Review.” Phys Med Biol. 2013; 58:37-61.
      2. Vogel A, Venugopalan V. “Mechanisms of Pulsed Laser Ablation of Biological Tissues.” Chem Rev. 2003; 103(2):577-644.
      3. Vitruk P. “Oral Soft Tissue Laser Ablative and Coagulative Efficiencies Spectra.” Implant Practice US. 2014; 7(6):22-27.
      4. Kaplan M, Vitruk P. “Soft Tissue 10.6-Micrometers CO2 Laser Orthodontic Procedures.” Orthodontic Practice US. 2015; 6(6):53-57.
      5. Strauss RA, Fallon SD. “Lasers in Contemporary Oral and Maxillofacial Surgery.” Dent Clin North Am. 2004; 48(4):861-888.

    This Education Center article was underwritten by Aesculight of Woodinville, Wash., the manufacturer of the only American-made CO2 laser.