In the western world, about 10% of the population is affected by fungal nail changes and there is a massive accumulation in older people, especially after the age of 60, slow nail growth, orthopaedic problems and after injuries to the nail organ, as well as in athletes or miners. Other risk factors are a weakened immune defence, either due to diseases such as diabetes mellitus or iatrogen in chemotherapy, as well as a disturbance of the microcirculation.

The disease usually begins at the toenails – often very slightly pronounced – with whitish stripes, blasting of the lamellar structures of the nail plate, onycholysis of the nail bed and ends with spreading to other toenails, rarely also on fingernails or the skin, and, finally, a partly crumbly destruction of the horn material with onychodystrophy and loss of the nail bed. Onychomycosis is divided into different forms depending on the pattern of infestation of the nails. Classically, a distinction is made:

• Distal subungual onychomycosis
• Proximal subungual onychomycosis
• Superficial onychomycosis
• Candida onychomycosis

The most common form is distal subungual onychomycosis, the most common pathogen is Trichophyton rubrum, a human pathogenic thread fungus, followed by Trichophyton interdigitale (mentagrophytes), another member of the same family. More rarely are nail infections with epidermophyton floccosum, or with mould or yeast fungi as pathogens. Mixed infections with moulds and bacteria are possible in moist areas. The detection is standardized and ranges from staining and microscopy, planting of cultures to fungal DNA detection by polymerase chain reaction (PCR)[1].

In mild cases, medical therapy starts with local application of antifungals in lacquers, solutions or creams. Before therapy, however, the exact diagnosis is made, taking into account the possible differential diagnoses [2, 3]. If more than 30-50% of the nail plate is affected, a systemic administration of itraconazole, fluconazole or terbinafine is recommended if no contraindications exist.

Today, a new therapy option has been established which can lead to success in minor cases and in younger patients as the sole measure [4, 5]. After evaluation of multiple studies, a response rate with improvement of the nail image between about 50-60% is indicated. However, the initial work on this topic is difficult or impossible to compare in terms of results. Open and controlled studies with very different patient groups, with and without conditioning of the nails in advance (grinding), with different therapy and observation intervals and laser devices have been published [4-17]. Despite everything, the tenor is predominantly positive, as two recent meta-analyses have shown [18, 19].

Since the treatment of over 600 patients in 7 years, in over 80% of the patients in combination with rotating grinding (reduction of fungal nail material), as well as adjuvant cream therapy at the nail edges, a significant improvement of the nail image and a suspension of the fungal attack could be achieved with the Nd:YAG laser therapy in our hands [5-7].

Two 1064 nm Nd:YAG lasers (Pin-PointeTM, Cynosure, USA and GENESIS plus, Cutera, USA) were used, which can penetrate the nail plate painlessly from the top to the nail bed and briefly lead to a selectively denaturing temperature increase (thermolysis). The exact mechanisms of action are still being investigated and discussed. We have been carrying out the Munich model of Nd:YAG laser therapy in the following form since 2010/2011: 1.) Atraumatic reduction of white, crumbly nail material by rotating grinding, 2.) Laser therapy (1064 nm, Nd:YAG), 3.) Supportive, long-term treatment with antimycotics in cream, solution or varnish, every 2nd day (Tab. 1). Oral antimycotics are completely dispensed with in this scheme.

If necessary, nail preparation with a grinding device prior to laser therapy is helpful (Fig. 1). The repeatable, accompanying mechanical removal of whitish or crumbly nail parts increases the effectiveness of laser therapy and also saves impulses and time. The rule of thumb here is: “Where the eye can see through, Nd:YAG laser therapy works better.”

The external application (co-therapy) of e.g. Terbinafin, Ciclopiroxolamine or Amorolfin cream on the skin of the surroundings on every 2nd morning leads, besides the protection of the nail edge, indirectly also to the reduction of fungal material and spores on socks, shoes and the close surroundings. Only the achievement of a cosmetically satisfactory situation with reduction of hyperkeratoses and outgrowth of clear nail results in a lasting satisfaction of doctor and patient.

In this paper we present 35 patients with problems in responding to the Munich model. A long resistance to therapy, deterioration of the findings and/or damage to the nail surface, led to an additional use of Amorolfin varnish, once or twice a week. Amorolfin cream was applied to the skin around the affected nails every second day. The Nd:YAG laser GENESIS plus (Cutera, USA) was used.

Fig. 1: Presentation of toenails, before and after treatment by rotating
grinding, according to the therapy concept of the Munich model. On both big toenails and on the toes D IV and D V right and D II – D V left there are whitish, crumbly parts at the distal nail areas (above). After
treatment with the Saturn AT Micro grinder (Gerlach, Germany), the white portion is significantly reduced and the predominantly transparent
nail portions can be treated with the Nd:YAG laser from proximal to distal down to the depth (Fig. 1, bottom). Findings directly before
the start of therapy are shown.

All 35 patients were documented by imaging with a photographic camera and according to the Onychomycosis severity index (OSI)[20]. This optimized Munich model was very well accepted by all patients and no undesirable side effects occurred. After 3, 6 and 9 months the patients presented themselves again and the Nd:YAG laser therapy was evaluated and continued. After 6 months, 26 of 35 patients experienced an optical improvement in nail findings and OSI. 6 patients showed stagnation, 3 patients reacted with a deterioration of the findings. Two of the affected patients with worsening decided to further intensify the therapy and received an additional dose of itraconazole in a very low overall dose. This combination of local application of an antifungal agent within Nd:YAG laser therapy according to the Munich model and a late, low-dose and shorter administration of an oral antifungal agent represents a successful, practicable, less side effect and sustainable therapy option. In order to improve the use of Nd:YAG laser therapy, controlled and randomized comparative studies should be used in the future in order to achieve optimal use of this promising therapy.

Last but not least, we would like to recommend a pro-active application of antifungal cream after therapy, e.g. twice a week, to reduce the high risk of recurrence.

Methods and results

Since the beginning of 2010, most patients have been treated according to the Munich model (Table 1) with satisfactory results. Even severe forms of onychomycosis of the toes showed clear response and much improved nail findings after 1-2 years [5-7]. However, one should not assume that at an age of 60 years and above, the toenails can be restored to the condition of 20 years ago, especially with accompanying orthopedic changes, such as hallux valgus. However, there are also disease processes in which the use of podological nail preparation, Nd:YAG laser therapy in combination with external co-therapy seems to be at a standstill after an initial improvement. Reasons for this can be different:

• Heavy strain on feet during work or sports (e.g. Usain Bolt)
• Traumas, hematomas
• Onychodystrophy, eczema nails, psoriasis nails
• Orthopedic malpositions with e.g. tower nails, partial onycholysis, onychogryopsis
• Long-term destruction of the nail bed at the sides or in total (e.g. by onychomycosis)
• Additional diseases, diabetes mellitus, chemotherapy, circulatory disorders, or other growth disorders
• Artificial nail materials
• Moist feet, additional pathogens (e.g. yeasts, bacteria)

To intensify the therapy in such cases, the authors initially decided to use additional external therapy measures. This included patients who had a disintegrity of the nail surface and/or a suspension of the progress of the therapy using the Munich model (Table 1) after about one year. Amorolfine nail polish (1-2 times a week) and amorolfine cream (every second day) were used in 35 consecutive patients for regular Nd:YAG laser therapy (laser: GENESIS plus, Cutera, USA). 2,000 pulses (14 J/cm2) were used for laser treatment according to the manufacturer’s recommendations. A follow-up examination and further treatment was carried out after 3, 6 and 9 months with good patient compliance. Before and at the above mentioned dates a photographic documentation was created and the Onychomycosis severity index (OSI) determined [20]. The average age of patients (N = 35) was 57.7 years for women and 55.6 years for men, representative of patients in our practices (Fig.2a). The times for determining the OSI are shown in Figure 2b (Fig. 2b, lower part). The evaluation refers to the infected big toes. The numerical values of the Onychomycosis severity index (OSI) before the start of the new therapy (1), after 3 months (2), 6 months (3) and 9 months (4) were determined.

At the beginning of the study, the average OSI was 15.63 for men, 12.13 for women and 13.88 for the big toes. OSI decreased continuously after use of the new therapy after 3 months (OSI = 10.72), 6 months (OSI = 9.87) and 9 months (OSI = 8.54) (shown for the whole group in grey).

Accordingly, the results were reflected in the separate evaluation of men (Fig. 2b, blue line, above) and women (Fig. 2b, red line, below). In 26 of 35 patients, a significant improvement in OSI and an optical improvement in nail findings was achieved. Only 6 patients showed stagnation, 3 patients reacted with a worsening of the findings under the current therapy within the observation period.

Case report 1

The 57-year-old patient introduced himself in 2013 with a previously culturally confirmed onychomycosis. The initial diagnosis was external and nail changes accompanied the athlete already over 7 years after a trauma with progressive atrophy of the left big toenail (Fig. 3, above). Other toes were affected. From then on, the patient introduced himself at irregular intervals in our consultation, he applied Terbinafin cream, was treated 6 times with Nd-YAG-Laser (PinPointeTM, Cynosure). This led to a significant improvement in D I on the right side and D IV and D V on the right foot until February 2016, when we decided to continue the therapy after the left big-toe nail slowly grew out (Fig. 3, bottom). It became clear that the left big-toe nail had benefited from the therapy for years and had now slowly formed a new nail bed, also in width (Fig. 3, lower row, right). A central onychoschisis also began to close. The patient had no systemic antifungal therapy during the entire observation period.

Case report 2

66-year-old patient with severe onychomycosis on several toenails with complete infestation on both sides of D I (not shown), under therapy with transient external measures for more than 15 years. Previous internal diseases of relevance did not exist. A cultural proof of fungus was externally positive. At first, a therapy according to the Munich model was carried out, under which a clear improvement began. A complete outgrowth of the big toenails could not be achieved (OSI 25). We then decided to use Amorolfine Nail Polish (1-2 times a week) and Amorolfine Cream (every 2nd day) as an accompanying therapy for regular Nd:YAG laser therapy (final result Fig. 4a, 10 January 2017). In particular it had now come to the outgrowth of firm nail plates at both big toes, which could not establish however a continuous connection to the respective nail bed. In addition, the patient often went on bathing holidays in salt water each year, resulting in an increase in onycholysis. At the beginning of 2017 we decided to administer itraconazole (50mg/the) adjuvantly orally for 4 weeks, followed by 2 capsules of itraconazole (2 x 50 mg) per week as an adjuvant therapy for regular Nd:YAG laser therapy. In total, 90 capsules of itraconazole were prescribed in the period from 10 January 2017 to 15 November 2017. Nd:YAG laser therapy was performed three times in 2017. Regular laboratory tests were inconspicuous, except for slightly elevated uric acid levels. Before the systemic administration of an antimycotic, it was not possible to restore the connection between the nail plate and nail bed.

Fig. 2a: Determination of the average age of the 35 patients treated with amorolfine lacquor, amorolfin cream and Nd:YAG laser. For women
it is 57.7 years (left), for men 55.6 years (right).

Fig. 2b: Initial values of the Onychomycosis Severity Index (OS I) according
to Carney et al. 2011[20], at the beginning (1) and at the examination dates after 3 months (2), 6 months (3) and 9 months (4). At the beginning of the study, for men an average value of 15.63, for women of 12.13 and 13.88 as a whole (middle line). The corresponding values
are shown separately for men (above) and women (below). The values
show a continuous decrease after 3 (OS I = 10.72), 6 (OS I = 9.87) and 9 (OS I = 8.54) months for the whole group.

70-year-old patient with severe onychomycosis on several toenails, especially with complete infestation on both sides of D I (not shown). The therapy according to the Munich model was carried out over several years. Cultural evidence of fungus was positive. Type II diabetes mellitus is known in internal diseases. Nail findings improved rapidly at the beginning, only from 2015 there was no further improvement. We used the external therapy with Amorolfin nail polish (1-2 times a week) and Amorolfin cream (every 2nd day) as an accompanying therapy measure to our Nd:YAG laser therapy. Despite further improvement, the result after 9 months was still not satisfactory, so that the adjuvant administration of itraconazole (50 mg/die) from February 2017 for 4 weeks, followed by 2 capsules of itraconazole per week (2 x 50 mg / week), was carried out as an accompanying therapy measure to our regular Nd:YAG laser therapy. The prescription in 2017 amounted to a total of 90 capsules of itraconazole. Nd:YAG laser therapy was performed 3 times in 2017. Regular laboratory tests were performed without any increase of liver enzyme levels. The toes D I-III on the right and D I on the left are now almost completely free of whitish markings, so that the itraconacol administration will be discontinued at the next planned follow-up.

Fig. 3a-d: 57-year-old male patient with onychomycosis on the toes
after trauma. The patient is an athlete and has noticed a slow, incessant receding of the nail bed on the left big-toe nail since the
beginning of the disease. The findings before the start of therapy with the Nd:YAG laser PinPointTM Footlaser and terbinafine cream (Munich model) in 2013 after a podolgic treatment are shown (Fig. 3, above). Representation of all toenails in the course of therapy until 2017 (below). The findings of the dystrophic left big toenail are partly shown in a magnification (right side).

Discussion and summary

The use of 1064 nm laser therapy for onychomycosis has now existed for almost 8 years [4]. There are still critical voices among experts, practitioners, health insurance companies and patients. We were able to apply this therapy option early and successfully apply an improved protocol with conditioning of the nails before laser therapy and continuous external application of antifungal cream, every 2nd day [5-7].

Now many patients have been released from our hands, a few have returned to 1064 nm laser therapy after a long time. For example, every year after the winter season two ski instructors introduce themselves to laser therapy for onychomycosis, as this is the only way to avoid systemic therapy. In about 10-15% of our patients we nevertheless experience a protracted, even less satisfactory progression. Our efforts are now aimed at exactly these, partly apparent therapy failures in order to maintain or improve the nail status and to reach the limits of onychomycosis therapy with the Nd:YAG laser. For this purpose, the Munich model of Nd:YAG laser therapy of onychomycosis continues to be used in our practices (Table 1). This work presents two possibilities for intensifying the Munich model.

Study situation

The Nd:YAG laser therapy of onychomycosis is enjoying increasing international interest. In the Pubmed medical database, the search terms onychomycosis and laser have more than 150 entries, of which over 30 are reviews and over 30 studies, the latter, however, with very different approaches and variable quality requirements. Two larger reviews (meta-analyses) have now appeared, which discuss the effectiveness and therapeutic relevance of many studies [18, 19]. Both come to a positive result, although the task of comparing the corresponding published application observations and studies is not easy. These do not apply the same therapeutic approaches. Initial reports were very positive about initial applications of very different devices, which should also serve as a basis for recognition by the Food and Drugs Administration (FDA 510(k)) [4,8,21,32]. This indication is CE approved in Europe. The Nd:YAG devices PinPointe^TM Footlaser (Cynosure), GENESIS plus (Cutera) were the first Nd:YAG lasers to receive FDA clearance for the treatment of onychomycosis [7, see Table 4]. Since 2009 many different devices with little comparable application pattern, mostly without conditioning of the toenails in advance, and with different wavelengths, penetration depths, energy characteristics, dose rates and spot sizes have been used [4-17].

Only from 2012 there were larger application studies, with and without pre- and/or post-treatment, with the use of the diverse lasers (intervals of one week to 3 months, different follow-up periods) [21-33].

After careful evaluation and critical examination of the data from 2009 to 2014 inclusive, Francuzik and his team were able to describe a clearly positive tenor with response rates of 50 % in a meta-analysis [18]. However, the number of laser applications in intervals varied between one and five in the studies. In addition to the Nd:YAG lasers with 1064 nm, longer-wave [26, 33] and short-wave systems [32] were also investigated with regard to energy source and wavelength. Diode lasers were also used [21]. However, their results do not seem as promising.

The overall positive results for laser therapy of onychomycosis have now been largely confirmed by newer, controlled and randomized approaches [21-32]. Conversely, a negative statement on the effectiveness of laser therapy of onychomycosis often depended on the study design, conditioning in advance, the device, application interval and also the observation period [12-14, 30, 33]. Especially the experiments without prior removal of whitish nail material as conditioning with too short treatment period (1-3, 1-5 months), compared with a longer observation period (12 months) and possibly an insufficient treatment protocol came to less favourable results. For example, Karsai et al. only reported the results at the end of the study after 12 months. After a treatment period of 3-5 months, the target points of negative fungal cultures and OSI data were then only assessed after 12 months [30]. The study had no results after 6 and 9 months. Thus, after one year, in our experience, the evaluation served rather to wait for the expected deterioration after an incomplete therapy or for a relapse. The Nd:YAG laser therapy of onychomycosis can only influence the condition during and shortly after thermolysis and not the future, renewed growth of the fungi 9 months later.

Fig. 4a: Representation of toenails of a 66-year-old male patient. A therapy according to the Munich model was carried out, most recently with amorolfine lacquor and amorolfine cream as co-therapy. From January 10, 2017, the additional oral administration of itraconazole (50 mg/day) for 4 weeks followed by 2 capsules of itraconazole
(2 x 50 mg) per week as an accompanying therapy for regular Nd:YAG – laser therapy. After about 3, 6 and 9 months continuous improvement of the nail findings with healthy outgrowth of the nails, especially D I, with formation of a connection to the nail bed (see Fig. 4a, 15 November 2017, bottom right) could be seen.

Fig. 4b: 70-year-old male patient with diabetes type II and severe
onychomycosis on several toenails. We used the external therapy with amorolfine lacquor (1 – 2 times a week) and amorolfine cream
(every 2nd day) as an accompanying therapy measure for regular
Nd:YAG -laser therapy. Despite further improvement, the result was not satisfactory after 9 months, so that the adjuvant administration of
itraconazole (50 mg/day) from February 2017 for 4 weeks, followed by 2 capsules of itraconazole per week (2 x 50 mg/week), was performed
as an adjuvant therapy for regular Nd:YAG -laser therapy. The toes D I – III
right and D I left are now almost completely free of whitish drawing (see
Fig. 4b, November 7th, 2017, below right).

Thus, since 2010 several studies have indirectly or directly confirmed the approach of our working group – according to the Munich model – with external co-therapy and therapeutic intervals of 2-4 months as well as longer follow-up times [18, 25, 28, 31]. Wanitphakdeedecha and staff evaluated 35 patients after Nd:YAG laser therapy after 4 treatment appointments at weekly intervals of 1, 3 and 6 months. If no improvement and/or absence of fungus was found, a new treatment cycle was performed [28]. This step-by-step approach, similar to the Munich model, seems sensible in order to achieve a lasting and pleasing result for patients.

Fig. 5: Schematic representation of the combination therapy of external therapy (left side), administration of systemic antimycotics (internal
therapy, right side) and Nd:YAG -laser therapy of onychomycosis
(Nd:YAG , bottom). The corresponding overlapping areas should symbolize
a common, strengthening effect (intersections). If all three forms of therapy come together, a further increased synergetic effect can be assumed (middle: best results).

The selection of study patients should also be discussed as another important aspect. Factors such as age, secondary diseases such as diabetes mellitus (case 3, this study, Fig. 4b), type of fungi and type of mycosis (case 1, this study, Fig. 3) play a role here. In a comparison of patient groups, there are certainly also significant differences in the success and speed of therapy between, for example, a centre of focus for diabetes mellitus [34] and a dermatological metropolitan practice [5-7]. Light and moderate onychomycosis in younger patients with better vascular supply and good compliance is certainly easier to treat.

Form follows function

The indication for the use of the Nd:YAG laser is similar to that for systemic therapy. Roughly speaking, if the nail plate is affected by more than one third to one half, a purely external therapy alone can no longer have any effect. Depending on the age of the patients and the type of infestation, however, it may also be necessary or advantageous to treat with Nd:YAG lasers even with minor infestation. Today a better therapeutic response can also be expected with regular conditioning of the affected nails by means of podological pre-treatment, as is also relevant for systemic therapy [35]. In contrast to this, according to our experience, the regular use of urea-containing exteriors to remove nail material prior to Nd:YAG laser therapy is more likely to have disadvantages: 1.) Since no nail growth, but the reduction of nail material is achieved. 2.) Since the milky cloudy nail substance after urea treatment is not well penetrated

by 1064 nm Nd:YAG laser. 3.) Since the forming, growing nail is to spread out as a splint in order to form the nail bed again, in order to allow sealing at the edges again later. 4.) Since women in particular appreciate the existing nail substance in order to be able to varnish the nail plates in summer.

Patients apply an antifungal cream to the skin of the anterior edge of the toenail and paronychia in the morning, every two days throughout the entire treatment period. A cream is advantageous because it creates a depot effect. The slowly spreading antifungal agent brings the gaps at the nail edge into contact with socks and shoes at the same time.

If the nail plate is completely affected, it takes more than 1 year until a healthy toenail can grow out after Nd:YAG laser therapy and external application of antimycotics under the combination therapy. The same time is also required under systemic antifungal therapy. Only if the healthy nail growth is stronger and the nail plate becomes more stable again, it is possible that the big toenails grow forward and the flanks let the nail grow again to a straight plate by contact at the sides (form follows function). We could observe in many cases that initial pincer nails with central rounding, softening and hyperkeratosis underneath became flatter again during the therapy and the hyperkeratoses had receded. Straight, soft nails with a central cavity and crumbly material are a perfect gap for the survival of onychomycosis. Conversely, a growing, firm nail can slowly form the nail bed again, similar to a glacier, which is followed by the bed of boulders and firmer rock after the ice has moved forward. Our most extreme example of this is presented in Figure 3 of this work (example patient case 1, this study). In the 57-year-old patient, it has now taken more than 4 years until about a third of the nail bed section had again developed under the Nd:YAG therapy according to the Munich model. The patient would not have agreed to a systemic antifungal therapy over this long period of time.

Side effects

The use of Nd:YAG lasers (PinPointe^TM, Cynosure, USA and GENESIS plus, Cutera, USA) according to the Munich model did not cause any significant side effects. Nd:YAG laser therapy should be performed in all cases without anesthesia and below the pain threshold. It is therefore up to the interaction of the practitioner with the patient to point this out and to interrupt the laser therapy immediately in the event of a feeling of heat. The abandoned area can cool down after a few minutes and then be visited again and treated with the heat jet. The avoidance of pain therefore depends mainly on the practitioner, not on the laser system used. Pain during therapy does not mean that it works better and should be avoided at all costs. The Nd:YAG-Laser PinPointe^TMFootlaser (Cynosure) has a comparatively small spot and a fast pulse frequency (20 pulses per second). This means that it works longer without pain than almost all other 1064 nm lasers, especially the long-pulsed Nd:YAG laser and can therefore send more pulses through/under the nail plate without generating heat or pain. The GENESIS plus system (Cutera) transmits 1064 nm rays in a comparatively larger spot and with a slower pulse frequency and is individually adjustable. This allows it to penetrate deeper and be adjusted more strongly. An external temperature display helps the dentist to change the toe before reaching the pain threshold.

If the control of the natural pain reflex is reduced or missing, we would work in a more careful mode and change between toenails a little faster. The application of 1064 nm laser therapy in patients with polyneuropathy, with or without diabetes mellitus, has never led to undesirable side effects in our hands. The most caution is required in toes with a serious vascular disease or florid infection, or close to gangrene, such as systemic scleroderma or a severe arterial circulatory disorder. In these cases there would be a contraindication, since heat damage to the tissue cannot be ruled out when blood circulation is suspended.

Systemic therapy

The administration of systemic antifungal drugs alone or in combination with Nd:YAG laser therapy of onychomycosis can lead to healthy nail growth and healing of onychomycosis. Therapy failures and recurrences due to short intake (residual mycosis) and discontinuation due to undesirable side effects are frequent [36]. Even after the nail has recovered after systemic therapy, new nail changes in the sense of onychomycosis can occur, depending on disposition and renewed exposure, without recurrence prophylaxis.

The combination therapy of Nd:YAG laser therapy with systemic antifungal administration and Nd:YAG laser therapy was investigated by Xu and her team. The efficiency of a combination therapy of long-pulsed 1064 nm lasers with and without oral terbinafine input was analyzed [37]. After 4, 8, 12, 16 and 24 weeks the patients were ordered back and the group with the combination therapy showed a clear superiority with regard to the therapeutic effect from the 12th week. The mycological examinations were also more favourable after 12 weeks in the patients with the combination therapy. Li and her team have also investigated the combination of Nd:YAG laser therapy and systemic antifungal treatment. A comparative study with itraconazole tablet intake and with itraconazole tablet intake plus laser therapy on 84 affected nails was used for this purpose [38]. The results indicated a statistically significant, additive effect with improved results in combination therapy. This was particularly true for the tough cases. El-Tatawy and colleagues compared a 4 times therapy with a long-pulsed Nd:YAG laser with a terbinafine tablet intake. The clinical findings after 6 months showed no advantage for taking the tablets. However, the course of therapy and the observation period may have been chosen too short [39].

We also see in our patients in this work that additional therapeutic measures, which showed individual effectiveness in advance – after exclusion of contraindications – the joint application can lead to an additive improvement of the therapeutic situation (Fig. 5).

It is very important, if one wants to achieve a “cure” of the evil of onychomycosis with nail changes, as it is currently discussed [40], that the education of patients to continue external antimycotic therapy must take place in the sense of a pro-active approach in most people. At the end of the therapy, if onychomycosis starts again, the patient should present himself to the therapist as soon as possible.