Article

Laser surgery of the larynx: the case for caution.

Ear, nose, & throat journal (Impact Factor: 0.88). 12/1992; 71(11):593-5.
Source: PubMed

ABSTRACT Laser surgery has been advocated for treatment of many laryngeal lesions. Although the CO2 laser has many advantages, its safe use requires special education of the surgeon and operating room team, and considerable surgical skill. Several dangers inherent in laser use for laryngeal surgery must be considered. These include vocal fold scarring secondary to thermal injury, loss of histopathologically important tissue through vaporization, airway fire and others. Laser-related complications must be considered whenever use of this instrument is contemplated.

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    ABSTRACT: CO2 lasers have become an important technological advance and an integral tool for the laryngeal surgeon since the 1960s. Surgeons have used lasers for a variety of benign and malignant lesions in the larynx with good success. With better understanding of the microarchitecture of the vocal folds and the recognition of heat distribution into surrounding tissues that occurs with the use of standard CO2 lasers, questions and concerns have been raised regarding the use of the CO2 laser for benign lesions of the vocal folds. With the advent of the microspot CO2 laser with a spot size of less than 250 μm, the potential heat distribution to the deeper layers of the lamina propria has been reduced. The microspot CO2 laser has been suggested to be an appropriate tool for the excision of superficial benign lesions of the vocal fold and may be considered as an appropriate treatment alternative to microdissection. Only a limited number of studies have compared the efficacy of microdissection versus microspot CO2 laser surgery in the larynx, and no prospective, randomized trials have been performed.Objective This study was designed to compare microspot CO2 laser excision and microdissection for superficial benign lesions confined to the free margin of the vocal fold.Study Design:A randomized, prospective trial comparing microspot CO2 laser excision and microdissection in the removal of nodules, polyps, and mucous retention cysts of the vocal fold.Methods Acoustic and aerodynamic measures and videostroboscopic and perceptual audio recordings evaluated by a panel of blinded viewers and listeners were studied preoperatively and 2 to 3 weeks and 5 to 12 weeks postoperatively. Surgical and recovery times were compared between the two groups.Results Thirty-seven patients met selection criteria and were enrolled, 21 in the microdissection group and 16 in the laser excision group. Significant improvements in videostroboscopic parameters were found over time in both groups. Significant improvements were noted for perceptual analysis over time for the laser excision group with nonsignificant improvements over time for the microdissection group. There was no difference in any measure between laser excision and microdissection at the two postoperative visits. There was no difference in surgical or recovery time between laser excision and microdissection. Acoustic and aerodynamic parameters were noncontributory in evaluating outcomes of treatment, since most values were normal before surgery.Conclusion No differences in clinical outcomes are identified when comparing microdissection with laser excision of nodules, polyps, and mucous retention cysts of the vocal folds.
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