Laser Treatment for Fungal Nails

What Are Fungal Nails?

Fungal nails also called Onychomycosis is a fungal infection caused by dermatophytes (fungi that need keratin for growth) and affects the nail unit. Apart from dermatophytes, saprophytic mold infections and yeast infections are also seen. It is a common condition and affects about 14 percent of the general population. Fungal fingernail infections are less common when compared to fungal toenail infections. Fungal toenail infections mostly present as discolored and thickened toenails.

Apart from causing cosmetic concerns, the condition can be an underlying etiology for secondary infections and ulcerations. It may lead to complications like cellulitis and erysipelas. Especially in the case of immunocompromised individuals and diabetics, these jagged toenails can increase the risk of ulcer development, leading to sepsis or amputation.

What Are the Different Treatment Options for Fungal Nails Other Than Lasers?

Medications: In mild infections, topical antifungal medications applied to the affected nails help overcome the infection. But the treatment should be continued for months and poor patient compliance may become a problem. However, the side effects are milder and do not stop the affected from using the medications. Oral antifungal medications are effective than topical ones and have a higher curing rate. The FDA has approved the following systemic antifungal:

• Terbinafine.

• Fluconazole.

• Itraconazole.

• Griseofulvin.

Combination Therapy: Combination therapy with topical medications, periodic debridement, and systemic antifungals provide better results.

Surgical Nail Removal: Surgical nail removal is indicated in case of severe infections where other options fail.

Why Laser Therapy for Fungal Nails?

The most effective and mainstay therapy for fungal nails is systemic antifungal. Oral terbinafine has a cure rate of 71 to 82 percent and a clinical response rate of around 70 percent when used for a 12-week course. The poor compliance of patients to the long treatment duration results in subtherapeutic drug effects.

In rare cases, the drug can elevate the liver enzymes, and the condition may progress to fulminant liver failure. Other side effects of the drug are loss of taste, headache, abdominal discomfort, etc. Another systemic antifungal used, Itraconazole, is found to have less clinical response rate and mycologic effect. Further, it may induce cardiac toxicity.

The following are some reasons for which laser therapy is considered for fungal nails:

• Due to the limitations of other options (systemic antifungal limitations discussed above), laser therapy has been proposed as an alternative treatment option.

• A convenient option with limited side effects.

• Effective and quick treatment.

• Simple procedure with quick recovery.

• Anesthesia is not required.

• Treatment can be done in a medical setting(office/hospital) with no requirement for patient adherence.

• Useful in patients where systemic antifungal medications are contraindicated.

What Is the Mechanism of Action of Laser Therapy?

The actual mechanism of action of laser therapy has yet to be discovered. However, several theories have been proposed. As per the theory of selective photothermolysis, the fungus' laser energy is selectively absorbed based on their differences in thermal conductivity, resulting in photomechanical and photothermal damage. But the adjacent human tissues are spared. Another theory suggests free radical formation due to the incident laser energy and absorption of light by xanthomegnin (fungal pigment). This pigment is highly concentrated in the fungus Trichophyton rubrum, a predominant pathogen for fungal nails.

What Are the Different Lasers Used for Therapy?

• Nd: YAG Laser: Nd: YAG Laser (neodymium-doped yttrium garnet laser) is a solid-state laser approved by the FDA (United States Food and Drug Administration) for treating onychomycosis. They continuously deliver energy in micro, nano, milli, or femtosecond pulses.

• Dual Wavelength Diode Laser: In dual-wavelength diode lasers, light is emitted by semiconductor diodes at 870 to 930 nanometers. The lipid cell membrane of fungi selectively absorbs these wavelengths and fungal cytochrome c oxidase, resulting in oxygen radical generation and photoinactivation of the fungi.

• Q- switched Lasers: Q-switched lasers have a pulse duration in nanoseconds. It has the highest energy density per pulse among the Nd: YAG Lasers.

• Solid State Lasers Other Than Nd: YAG Laser: Other solid-state lasers include erbium-based devices and titanium-based devices. Titanium: Sapphire lasers have pulse lengths in femtoseconds. These lasers deliver an adequate amount of energy per pulse and, at the same time, spare the adjacent tissues from excessive heating due to their high thermal conductivity.

• Fractional CO2 laser: Fractional CO2 lasers are indicated in matrixectomies. It ablates the growth plate and disrupts fungal growth.

How Is the Procedure Carried Out?

• Firstly, the patient will have a consultation with the physician, where the laser therapy suggested by the physician will be explained to the patient.

• During the toenail examination, the physician schedules a debridement appointment for a day before the laser procedure or on the same day as the procedure. Debridement involves the removal of dead skin cells.

• Before starting the procedure, the toes are cleaned using a sterile solution, and the legs are positioned properly.

• The laser device is placed over the infected toes by the aesthetician. The laser is set to a specific wavelength to minimize the side effects.

• The treatment sessions mostly last an average of thirty to forty minutes.

• The procedure is mostly comfortable, but the patient may have a warm tingly session.

• Mostly, four sessions are required for complete fungal eradication.

Does the Treatment Improve the Appearance of the Nail?

Fungal eradication may not improve the nail appearance as the nails may have been traumatized by the fungi or due to previous trauma. The treatment mainly aims at mycological cure and clinical recovery. As the nails grow slowly, it takes months to regain their lost appearance. Relapses mainly occur due to incomplete fungal eradication or reinfection. Reinfection can be minimized by following aftercare measures after laser treatment.

Conclusion

Laser therapy for fungal nails is a safe, efficient, and alternative option, especially in those cases where systemic antifungals are contraindicated. The procedure is non-invasive, quick, and has limited or almost no side effects. But a chance for reinfection exists, and multiple sessions may be necessary. The cost of therapy depends on several factors: the number of nails affected, the geographic location, and the complexity of the procedure.