Systematic Review of Laser Therapies in Onychomycosis: Update 2014
Last five years have been especially interesting considering the novel therapeutic strategies for onychomycosis. We have whitnessed the emergance of a number of medical devices designed for toe nail fungus elimination using light irradiation. Those new options called for a comparison of currently used medication therapies and novel laser-based strategies. The discussion about the effectiveness of new possibiities also became very vigorous in the last years. Investigators encountered multiple problems in defining the usefullness of new therapies which mainly depended on the inability of properly define diagnostic and nomenclature rules as well as setting the unified outcome measures for cross-study comparisons. In this paper we tried to calrify what was already done in the topic of laser based toe nail fungus treatments and propose methodology for unifying furhter studies in this field. It has become clear that laser light sources may play an inevitable role in the treatment of onychomycosis. Recent meta-analysis estimated that the mean prevalence of onychomycosis in Europe and North America is 4.3% in the general population (Sigurgeirsson 2014). The development of devices designed specifically onychomycosis in flourishing. Nevertheless the scientific basis for their effectiveness is not always obvious. They virtually lack therapy side effects (aside from pain during the procedure) and are therefore preffered in patients with contraindications for oral antifungal pharmacotherapy.
We decided to revise the literature and summarize the knowledgce on lasers in the treatment of onychomycosis. Our analysis consists of two following parts: 1) evaluation of clinical trials with background on the theory of laser therapy; 2) Our ideas of what measures should be undertaken in order to conduct more reliable research in this field.
We have performed a literature search in Pubmed, Web of Science, Google Scholar and EBSCO data bases usng the string: “onychomycosis laser”. Any paper or conference report published in peer reviewed journal, or with enough details, as a white paper was considered for inclusion in this reiview. The database of Pubmed, Google Scholar and Web of Knowledge were searched using the query “laser onychomycosis” restricted to appear in the title only and lacking the term “review”. Initial search yealded 926 papers. Aside from papers in English language also German, and Portugese papers were included in the study. The search strategy is summarised in figure 1.
We have evaluated 21 papers from 13 countries (Table 1) and identified 5 laser types used to treat onychomycosis. In articles where authors reported the model we recognised ten different commercially aviable devices of which 7 were neodymium-doped yttrium aluminium garnet (Nd:YAG) lasers 1 was Erbium:glass laser and 2 were low level class 2 diode lasers. One paper was a follow up on the same sample using the same laser, we deciced to include only the follow up report results. (Landsman 2012)
The Nd:YAG Lasers were the first lightsources designed specifically for the treatment of onychomycosis . 17 out of 23 papers described treatment using some sort of Nd:YAG device. One report used the doubled wavelength of 532 nm in conjunction with 1064 nm the rest used 1064 nm wavelengths in different settings to treat onychomycosis. The specific settings described in the literature can be found in table 1.