KTP 532 nm Laser for Laryngeal Lesions. A Systematic Review

Objective To evaluate the effectiveness and safety of the 532 nm potassium titanyl phosphate (KTP) laser for vocal fold surgery. Study Design Systematic literature review. Methods Our systematic review was conducted using the meta-analysis of observational studies in epidemiology guidelines. We applied the criteria of the Oxford Centre for Evidence-based Medicine to assess the level of evidence. Results We identified seven observational studies of eight case series, which reported a total of 243 KTP procedures carried out for vocal fold lesions: two series each concerning ectasias and varices, early glottic cancer, and recurrent papillomatosis, and one series each for keratosis with dysplasia and various benign laryngeal pathologies. There was also a retrospective review of the use of KTP laser in 387 endoscopic laryngeal surgeries. No studies compared the use of KTP laser with that of other technologies. Thus, according to the Oxford criteria, there is only level 4 evidence of KTPʹs efficacy and safety. In selected cases, the KTP instrument can be used without general anesthesia in the clinic setting. Conclusions The use of KTP laser for laryngeal surgery is still relatively innovative. Several surgeons have found KTP laser to be the equivalent of, or superior to, the CO2 or pulsed dye lasers, and none have reported inferiority. However, there are currently no published data to support these conclusions. To establish equality/superiority, it is desirable that further evidence of efficacy and safety be obtained, either through randomized controlled trials or at least through well-documented prospective observational studies with reporting of all relevant input and outcome data.