Emphasizing The Importance Of EBM When It Comes To Laser Care For Onychomycosis
I read with concern your Point-Counterpoint article, “Laser Care For Onychomycosis: Can It Be Effective?“ in the May 2010 issue.
In the modern practice of medicine, there are two separate but mutually supporting doctrines in what is known as evidence-based medicine. The first doctrine is “to treat individual patients with acute or chronic pathologies by treatments supported in the most scientifically valid medical literature.” The second doctrine is “the systematic review of medical literature to evaluate the best studies on specific topics.”1
Given the above, I must take exception to a scientific conclusion described within the laser article. When discussing the 1064 nm Nd:YAG laser, John Mozena, DPM, states that the single wavelength of light causes destruction of the fungal cells in onychomycosis (see page 56 of the May 2010 issue).
To my knowledge, there are only two peer-reviewed and published studies looking at existing near- infrared lasers in vitro to destroy fungal cells, other than the data published on the Noveon laser. The first, conducted by Vural and colleagues in 2008, showed that a Q-switched 532 nm light (visible green) laser in the Nd:YAG family was actually superior to all other systems tested, including a traditional 1064 nm FRP Nd:YAG in T. rubrum inhibition.2
The authors concluded their study with the statement: “In addition to more in vitro studies, in vivo studies are necessary to investigate the possible therapeutic effects of various laser systems on various dermatopathogens, as laser–fungus interaction might be different when these microorganisms are embedded within the skin and its adnexa.”2
The second study used a femtosecond infrared titanium sapphire laser, which pulses at 10-15 of a second. This laser did successfully inhibit growth in vitro of T. rubrum.3
At present, if one were to take a critical look at the available published peer-reviewed literature that discusses all lasers used in vitro and in vivo in the IRB-controlled human treatment of onychomycosis, one would realize that the entire body of this research comes from scientific and medical testing with the new Noveon laser, with two of the studies published in the Journal of the American Podiatric Medical Association.4-8
In the most recent publication, Landsman and colleagues tested the Noveon laser with key parameters in an IRB-controlled pivotal human study.4
1) The study involved single blinded and control patients treated identically in all respects to patients who were actually treated with the laser with
the exception of the sham (placebo) laser treatment.
2) There was an independent expert panel of podiatrists that used baseline photographs to classify each toe in the study as mild, moderate or severe involvement at the outset. The members of the panel were blinded as to which photographs came from treated patients or control patients.
3) The same panel used follow-up photographs to grade clinical improvement subjectively in the nails. The data was statistically analyzed and produced by an independent clinical research organization that is certified to perform this function for the FDA.
Where Is The Evidence On The Other Lasers?
As of this writing, there are four different Nd:YAG lasers and two different diode lasers being marketed to podiatrists as being able to treat onychomycosis, and there is not a single peer-reviewed, IRB-controlled, blinded study among them to justify onychomycosis treatments with these devices. Also, not a single research group has come close to producing the five years of predicate in vitro, animal, cadaver and IRB-controlled human studies with any one of these lasers that my team has published with the Noveon laser, leading up to the treatment of human onychomycosis.4-8
Therefore, until such time as any Nd:YAG or near-infrared diode laser has been tested and has published peer-reviewed evidence that matches the rigor of our team’s efforts during the last five years, I will continue to take exception to comparisons with any “anecdotal evidence” for one of these lasers.