Hot vs Cold Laser for Fungal Nails: Which Is Best?
The introduction of laser treatment began an exciting non-pharmaceutical era in fungal nail management. Podiatrists can finally feel confident in recommending an antifungal treatment without sending their patients to a GP for prescription medication or hesitantly directing them towards topical applications that demand high levels of patient compliance as they must be used daily, while also taking 6-12 months to show results and having less-than-ideal success rates.
With antifungal lasers now being used extensively in podiatry clinics to deliver superior results for infected, damaged nails, there’s one key decision that must be made when it comes to introducing laser as a profitable service to a clinic: is hot or cold laser better?
Given that the decision extends beyond clinical efficacy and impacts a clinic’s reputation, profitability, practitioner utility and patient satisfaction, we have compared the evidence supporting both the hot and cold lasers and evaluated the pros and cons to help you make the best decision for your clinic.
Efficacy
Hot laser uses thermal properties, manually heating the affected nails to approximately 46-48 degrees, thereby creating a fungicidal effect and damaging the fungal cells. Hot laser has had its efficacy evaluated over a limited range of primarily small scale studies with variable results that promisingly all follow a “trend towards improvement”.[1]
Results range from cure rates of 33%[2], to “good treatment outcomes” in 72% of nails treated, where the actual cure rate was 9.3%.[3] The largest efficacy review of hot lasers included 4278 infected nails, and produced a total cure rate of 63%.[4] Recent studies have shown a visual improvement rate as high as 86.7% if treatment protocols are amended and standardised[5]. Other studies have reported hot laser being completely ineffective in eradicating nail fungus after 29 days[6], as well as having a 0% mycological cure after 12 months, which may be attributed to a high rate of re-infection during this long time period.[7]
As ‘hot laser’ includes a variety of devices operating at different wavelengths, it’s important to look into the research behind the specific hot laser device you are considering investing in. The Pinpointe laser, for example, has found mycological cure rates of between 51% and 53%.[8] Additionally, be sure to examine the treatment protocol within the efficacy studies. In multiple studies with high efficacy findings, hot laser was only one part of a multi-faceted approach, which may impact on the replicability of the results in a clinical setting.
Cold laser utilises cool laser wavelengths to produce fungicidal effects. Specifically, the Lunula laser, the world’s leading cold laser and the one used in most studies evaluating cold laser efficacy, has a dual-diode approach, where two heat-free laser beams operate in unison to target the fungal cells while fortifying the body’s natural defense mechanisms. Cold laser has repeatedly achieved comparable, and seemingly superior results to thermal laser, while consistently being the primary treatment modality in studies instead of alongside other forms of management.
Efficacy results for cold laser range from demonstrating an 89% clear nail increase with a 67% treatment success rate,[9] to showing clinical cure and mycological cure rates of 70% and 95% respectively. These figures rise to 90% and 95% by 12 months, with 100% of study participants having new unaffected nail growth.[10] Studies conducted using strict protocols by the laser manufacturers have confirmed individual success rates to be as high as 86% at week 12, extending to 99% by week 48.[11]
When examining any laser results, it’s important to differentiate between the degree of severity of nails affected, as many patients will present with extreme fungal severities, and some hot laser studies we observed excluded heavily affected nails. One Lunula study, where on average 81% of the toenail was affected by fungus, showed that 63.6% of toenails reached full clearance.[12] Two audits completed by clinics using the cold laser in patient management have reported success rates of 84-87%[13] and 89%[14] over 12-18 months.
Ease Of Use & Treatment Time
Hot laser is a manual treatment process performed by a practitioner in the clinic. After the patient’s nails have been prepared through a nail trimming and debridement process, the laser is applied over the entire nail, extending to the outer nail and skin edges. This is a stop-start procedure that covers as many toes as is determined by the clinic. Treatment times range from 30-60 minutes and are influenced by each patient’s heat sensitivity. Hot laser can only treat the area of the infected nails that is visible and therefore accessible to the treating physician. Any fungal cells embedded in the germinal matrix cannot be visualised, so cannot be treated with any hot laser device. This may help explain hot laser’s failure rate.
Cold laser is a hands-off, automated procedure performed in the clinic. The patient’s nails are also first prepared by a podiatrist as with thermal laser. Next, the foot is placed inside the cold laser device and treatment commences. The rotating lasers run for 12 minutes per foot, acting on the entire foot and all toenails. There is no intervention by a podiatrist during the time, aside from assisting the patient to switch feet and checking on them. The patient is free to sit back and relax. The podiatrist may leverage this time to provide education or re-infection prevention. The total appointment time is 30 minutes. The mode of action of the Lunula cold laser is photo-biostimulation, which initiates a physiologic response. The cold laser’s mode of action not only treats the visible nail plate but includes the nail matrix and germinal layers. The physiologic response provides total therapeutic coverage to all infected tissue; nail plate, nail bed and germinal nail matrix.
Safety & Contraindications
Hot laser is contraindicated in use with patients with diabetes, neuropathy or other nerve damage which may render them unable to detect pain or may affect their healing rate. Using thermal laser under these circumstances can have severe consequences, as reported in a case study where a 64-year-old female patient had the thermal Pinpointe laser treatment, after which necrotic lesions developed over the nails bilaterally, and despite the use of antibiotics, she underwent amputation of her two great toes after one month.[15] Due to the manual application of the laser and the heat involved, there is always a risk of burns, discomfort and pain. Also, hot laser treatment creates laser plume which can contain viable bacterial, viral and fungal pathogens which which may be inhaled by the patient, treating physician and any staff members in the treatment area.
Cold laser does have clear superiority in this domain, having no contraindications, reported side effects, and being labelled as 100% safe for all users. The power reaching the surface of the skin is 1mW and there is no increase in the temperature of the exposed tissue. There have been no reports of adverse events across the studies, creating a simple and painless therapy.
Patient Satisfaction
Hot laser has demonstrated good levels of patient satisfaction resulting from producing desirable results in the studies. An emerging theme from the studies, however, is the significant presence of mild, moderate or severe discomfort or pain throughout the treatment,[16] even without sustaining burns, which has a great potential to reduce satisfaction rates.
Cold laser has demonstrate excellent patient satisfaction rates, including a study of 320 patients using the laser that resulted in a 93% satisfaction rate.[17] Given that the laser is pain-free, comfortable, convenient and does not carry a risk of burns or require local anaesthesia, cold laser does appear to be positioned for a greater level of patient satisfaction in a clinical setting.
Additional benefits of cold laser that improves satisfaction rates include there being no risk of developing a microbial resistance, no medicinal interactions or risk of liver toxicity, and high compliance from a painless procedure. Similar points also apply to hot laser, however there have been many reports of hot lasers causing pain, occasional bleeding after the treatment, or darkening the nail plate.
The Verdict: Cold Or Hot Laser?
Based on its safety, efficacy and patient satisfaction, we see cold laser as the superior treatment for practitioners wanting to invest in a laser solution for onychomycotic nails. It’s important for any service offered by clinics to not only work for their patients but for the practitioners too – simplifying their processes, reducing the risk for error, building a strong reputation, and improving their time efficiency for maximum profitability as a business, too. Cold laser strongly delivers on all of these aspects, filling the ‘gaps’ left by its thermal counterpart.
To learn more about what having the laser in your clinic could look like including expected profitability and complimentary marketing plans, contact us at RehaCare at 1300 653 522 or visit Lunula Laser website.
[1] https://www.karger.com/article/FullText/492526
[2] https://jfootankleres.biomedcentral.com/articles/10.1186/1757-1146-7-34
[3] https://pubmed.ncbi.nlm.nih.gov/24693870/
[4]https://journals.lww.com/md-journal/Fulltext/2019/11290/Laser_treatment_for_onychomycosis__A_systematic.11.aspx
[5] https://www.mdpi.com/2304-6732/8/9/350
[6] https://pubmed.ncbi.nlm.nih.gov/24740521/
[7]https://www.hmpgloballearningnetwork.com/site/podiatry/blogged/recent-research-shows-failure-laser-therapy-monotherapy-onychomycosis
[8] Long-pulse Nd:YAG 1064-nm laser treatment for onychomycosis. Zhang RN, Wang DK, Zhuo FL, Duan XH, Zhang XY, Zhao JY Chin Med J (Engl). 2012 Sep; 125(18):3288-91.
[9] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5479474
[10] https://www.peertechzpublications.com/articles/IJDCR-7-140.php
[11]https://www.coldlasernailclinic.nz/wp-content/uploads/2018/03/ERCHONIA-LUNULA-Toenail-Onychomycosis-Clinical-Study-Results-Report-FDA-3.docx
[12] https://www.podiatrym.com/pdf/2017/1/Tumolo117web.pdf
[13] https://www.compleetfeet.co.uk/lunula-laser-fungal-nail-audit-201617/
[14] https://www.podiatrym.com/pdf/2017/1/Tumolo117web.pdf
[15]https://www.academia.edu/42352851/Diabetic_neuropathy_and_Nd_YAG_1064_nm_laser_for_onychomycosis_be_careful
[16] https://hekyll.services.adelaide.edu.au/dspace/bitstream/2440/91060/3/02whole.pdf
[17]https://www.opnassociation.ca/wp-content/uploads/2019/09/Sullivan_Erchonia-Laser-Therapy-in-the-Treatment-of-Onychomycosis-Preliminary-Report_Podiatry-Review-Vol-71.2_03_14.pdf