Clearanail Clinical Trial Feedback
Rapid clearance of sub-ungual onychomycosis by controlled micro
penetration and topical terbinafine solution using the Clearanail® device
Dr. Ivan Bristow, Faculty of Health Sciences, University of Southampton and Michelle Score, Private Practitioner, Lymington, Hampshire.
Onychomycosis continues to be a common and troublesome problem, often responding poorly to drug treatment. Toenails are most frequently affected by the infection – particularly the hallux (big toe). The causative agents are typically the dermatophyte species of fungi which spread from plantar skin over many months to invade the nails through a distal and lateral sub-ungual route producing the characteristic discolouration of the nail plate. Over many months, complete invasion of the nail may lead total dystrophy. Fungal toenail infections are often trivialised as a cosmetic condition, but studies have confirmed its effect on the patient’s wellbeing and quality of life. Moreover, the presence of fungus on the foot is a risk factor for the development of lower limb cellulitis – a particular risk for patients with peripheral vascular disease and diabetes who have an increased propensity for the disease.
Management of the condition to date has proved challenging. Oral medication have shown good mycological cure rates when taken over several months. However, potential side effects, drug interactions and reluctance from some patients to oral medications remains a limitation.
Exploring new techniques, the use of lasers has been suggested and reported as a less invasive and safer technology to destroy the infection by rapid heating of the infected area. However, results from a recent systematic review have suggested that it has little evidence to date to support their widespread use in Onychomycosis.
Topical treatments, applied directly to the nail plate, have also been used widely but consistently have been shown to be less effective than the systemic drug regimes. The nail plate is naturally a barrier to drug penetration, effectively shielding the sub-ungual area so the underlying infection remains protected. In addition, patients are expected to apply the medicament to the nail for many months. Studies of topical medicament usage have shown that compliance decreases the longer the treatment continues which may result in a treatment failure. Measures designed to enhance topical drug delivery have been trialled with some success. Chemical penetration enhancers have been developed and incorporated into many topical drugs to boost delivery of the active ingredient through the nail.
In 2013, a new device was invented and patented in the UK, with the potential to overcome a number of these issues. The Clearanail® device is based on a simple nail drill design with a unit and hand piece and is fitted with a single use 0.4mm carbide micro cutter. Using a micro cutter, the drill when applied vertically to the nail and activated, bores a hole directly into the nail plate but safely stops once it is through the nail plate before damaging the underlying soft tissue of the nail bed. The result is a nail plate which can be successfully perforated with multiple holes. This then makes the nail(s) more permeable, and it can be expected that chemicals and drugs would have a more rapid journey to the nail bed allowing a faster, antifungal effect at the heart of the dermatophyte infection.
Patients with laboratory and clinically confirmed Onychomycosis who elected for topical therapy were offered the additional treatment with Clearanail. Nails were treated pre-operatively with chlorhexidine spray and then multiple holes were drilled through the nail plate into the infected areas of the nail plate, a few millimetres apart, with some overlapping the diseased area onto uninfected areas of the nail. The number of holes required being proportional to the amount of nail infected.
Patients were then instructed to use a 1% terbinafine spray (Lamisil® AT 1% Spray [Novartis UK Ltd]) on the drilled nail and to leave it on for a few minutes to allow the solution to drain through the holes. Patients were asked to continue this once daily and were reviewed on a regular basis to assess progress. Photographs were taken at week 1 and subsequently at review for visual comparison.
Contact the team on 02392 388149 or 07795 522700 for a consultation and treatment.