Onychomycosis is a fungal infection usually caused by a special type of fungus known as a dermatophyte. These sorts of fungi are generally confined to the dead, horny outer layers of the skin and gradually progress to involve the nail plate. Onychomycosis is particularly common in toenails of older men but can affect all of the nails of individuals of any age and sex. The treatment of this condition is complicated by the fact that these fungi live in dead tissue, and getting medications to these sites is problematic.
What is the traditional treatment of onychomycosis?
Because most of these infections are relatively superficial, it would seem that topical treatments ought to work well. This is not the case because the nail unit is relatively impenetrable. In addition, it is common for these infections to be entirely asymptomatic (not producing symptoms), which doesn't seem to diminish the patient's distress with the unpleasant appearance of the nail. A perfect treatment modality would be inexpensive, very effective, and very safe. Sadly, we have not achieved this perfect situation yet.
Currently accepted treatments include relatively ineffective topical therapies and oral treatments which are reasonably effective but are associated with some degree of risk. Both approaches require a long duration of treatment and the topical therapies in particular are somewhat costly. Most experts agree that surgical approaches like removing the nail plate are ineffective.
How does laser treatment work to treat onychomycosis?
It is into this environment that the use of lasers has been thrust. Of course, lasers are a very sexy, modern, technologically advanced approach to the treatment of a variety of human diseases. Lasers produce coherent light energy of a sufficient strength and of a specific wavelength, which when projected into tissue is differentially absorbed by the target material, producing heat and hence destroying tissues. Other tissue components are unaffected and so spared. Medical lasers are rather expensive devices, so treatments with these machines requires generally quite high fees to recoup the original purchase price of the equipment. It is proposed that some lasers might work by heating up the nail sufficiently to discourage fungal infections. Another approach to laser treatment of the nails uses a fractional CO2 laser to burn holes in the nail plate through which topical antifungal drugs can effectively penetrate.
Do lasers work better than the medical approaches for the treatment and cure of onychomycosis?
Since laser treatment is very new, the data to answer this question are just not available yet, while there is substantial evidence to support the efficacy of medical therapy. Most avid commercial radio station listeners can testify to the prevalence of advertisements touting laser therapy for abnormal nails. Recent reviews of the subject by various journals lament the lack of blinded comparison studies without control groups of sufficient numbers of patients to prove the effectiveness of lasers in treating and curing onychomycosis. A critical interpretation of these studies indicates that laser treatment of onychomycosis is not ready for prime time and should only be used in situations where everything else has failed. It is probably reasonably safe, but its efficacy remains to be proven especially when compared to other accepted treatments. In addition, no long term studies of effectiveness are available, so short-term gains may not translate into cures. As far as cost is concerned, it is unlikely that laser treatment would be less expensive than current medical therapy.
Bristow, Ivan R. "The Effectiveness of Lasers in the Treatment of Onychomycosis: A Systematic Review." Journal of Foot and Ankle Research 7 (2014): 34.
Vlahovic, Tracey C., et al. "Diagnosis and Management of Onychomycosis." JAPMA Article in Press. 1-22.