Efficiency of KTP laser for verrucae vulgaris and plantaris: A retrospective analysis

Verrucae are benign proliferations caused by human papillomavirus. Treatment is needed for pain, bleeding, contagiousness, and cosmetically.


| INTRODUC TI ON
Verrucae are benign proliferations of skin and mucous membranes caused by human papillomavirus infection. 1Treatment is needed due to symptoms as pain and bleeding, contagiousness, and cosmetically bad appearance.Aggressive and painful methods should be avoided as spontaneous regression is always possible. 2 Destructive methods (electrocauterization, laser, cryotherapy, etc.), virucidal treatments (gluteraldehyde, formaldehyde, etc.), antimitotic treatments (bleomycin, podophylline, etc.), and immunotherapy agents (imiquimod, intralesional vitamin D therapy etc.) can be preferred in the treatment of verrucae. 3,4However, there is no 100% effective method yet. 5e use of lasers has been increasing in recent years.Carbon dioxide (CO 2 ) laser, Erbium-YAG (Er:YAG) laser, Neodymium-YAG (Nd:YAG) laser, pulse dye laser (PDL), potassium titanyl phosphate (KTP) laser, and holmium lasers can be used in the treatment of verrucae. 5,6 this study, we retrospectively evaluated the efficacy and safety of KTP laser treatment in patients with palmar and plantar verrucae.
Prior to this study, necessary ethical permissions were obtained from Mersin University Clinical Research Ethics Committee, and the study was conducted in accordance with the Declaration of Helsinki.

| Patients
The patients who had V. vulgaris and V. plantaris treated with KTP laser, admitted to Mersin University Dermatology Clinic, between 2012 and 2013, were scanned.All V. vulgaris lesions were localized on the hands.Patients who had not been treated with any of the other treatments, and did not have immunosuppression or serious systemic disease were included in the study.The lesions were photographed before and after the treatment.

| Intervention
Before the application, a protective gel (ultrasound gel) was applied to the lesion area to prevent laser-related burns.The standard KTP protocol of our clinic for verrucae is as follows; 2 mm application width, 40 millisecond pulse time and 40 joules/cm 2 energy, including verrucae and 1 mm of intact skin around it.Two laser passes were performed per verrucae in each application.The standard protocol was applied to all patients, the interval between sessions was 2 weeks.The energy was increased to 50 joules/cm 2 if lesions did not regress clinically after four sessions.Treatment was continued for up to six sessions.

| Evaluation of clinical response
The lesions were photographed and lesion activity was evaluated at each control.The keratotic tissue on the lesions was debrided with a scalpel at each visit to assess lesion activity.The session was performed in the presence of punctate bleeding foci caused by dermal papillomatosis.The disease was considered active and treatment was continued until no punctate bleeding was seen.

| Side effects
The level of pain during the procedure was scored as follows; • 0 points: no pain • 1 point: minimal pinprick pain

| Follow-up
The patients' records at 3 and 6 months after the end of treatment were revised to evaluate the side effects and recurrence.

| Statistical analysis
The SPSS (Statictical Package for Social Sciences) 16.0 program was used to create the database and statistical analyses.Chi-square test was used in the statistical evaluation of the data.p < 0.05 was considered statistically significant.

| Patients
Twenty-nine patients who met the inclusion criteria were included in the study.Nine of the patients (31%) were male, and 20 (69%) were female.The cases were between 13 and 47 years old, and the mean age was 22.41 ± 8.18 years.There were 1-8 verrucae in each patient and the mean number of verrucae was 2.83 ± 2.04.Disease duration was between 1 and 72 months and the mean disease duration was 16.03 ± 17.68 months (Table 1).Nine (31%) patients had V. plantaris and 20 (69%) patients had V. vulgaris.All patients had a total of 82 verrucae.Twenty-four of them (29%) were V. plantaris and 58 (71%) were V. vulgaris (Table 2).
One-six sessions of laser treatment were applied to the patients.The mean number of sessions was 3.49 ± 1.57 for all patients.

| Clinical response
In the evaluation of clinical responses of patients to KTP laser therapy; complete recovery was observed in 24 patients (82.8%) (Figures 1 and 2) and partial response was observed in two patients (6.9%).Three patients (10.3%) were unresponsive to treatment after six sessions (no recovery).No exacerbation was observed with treatment in any patient (Table 3).
Seventy-three (89%) of 82 lesions had complete recovery, while seven verrucae (8.6%) showed no response.Partial recovery was seen in two verrucae (2.4%).In complete recovery group, 52 lesions were V. vulgaris and 21 were V. plantaris (Table 3).There was no statistically significant difference between the two types of verrucae in terms of laser treatment efficiency (p = 0.482).Of the 73 verrucas that responded fully to treatment, 63 (86.3%) regressed in the first four sessions, while only three verrucas (4.1%) required a sixth session (Table 4).

| Side effects
Two patients scored 0 point, 16 patients scored 1 point, and 11 pa-

| Recurrence
Among 24 patients of the complete recovery group, six (25%) patients developed recurrence within the first 3 months.

| DISCUSS ION
An ideal verrucae treatment should result in complete regression of the lesions, the pain should be absent or tolerable, the side effects should be minimal, and it should be applicable to all patients. 7P laser beams are absorbed by oxyhemoglobin in the dilated capillaries of verrucae and cause selective damage to the vascular structures by increasing local tissue temperature. 8mplete recovery was achieved in 82.8% of the patients, only two patients had mild pain during the application and 65.4% of the patients still had complete cosmetic recovery at the 3rd month follow-up.

Gooptu et al. reported 12 (48%) complete recovery, eight (32%)
partial recovery, and five (20%) treatment failure in 25 patients with verrucae (one located on the face and the others on the hands and feet). 8KTP laser parameters were 1 mm application width, 30 ms pulse duration, and 15-18 J/cm 2 energy, in their study.They applied maximum four sessions with 1 month intervals and scanned the lesions twice. 8In our study, each verrucae was scanned twice, but our energy amount was higher and our session intervals were shorter.
Because of this, our treatment efficacy and full clinical cure rates may be higher.While they used topical anesthetic in two patients, none of the patients included in our study required local anesthesia and our pain scores were better than theirs.
Another treatment option in wart treatment is Nd:YAG laser with a wavelength of 1064 nm.It targets the dilated capillaries in the warts and causes coagulation with photothermal effect. 9,10In a study with Nd:YAG laser treatment in verrucae, complete recovery was obtained in 336 (96%) of 348 patients, and patients were treated between one and four sessions (mean 1.49). 9The effectiveness of KTP laser treatment was found lower, and the average number of sessions were higher (mean 3.49) in our study.However, it was reported that 82% of the patients who underwent Nd:YAG treatment required local anesthetic injection in the second session due to severe pain whereas topical anesthetic cream could control the pain during the first treatment. 9None of the patients in our study had severe pain to require local anesthesia.Temporary numbness (15%), hemorrhagic bullae (7%), hyperpigmentation (5%), and hypopigmentation (4%) were reported as side effects in Nd:YAG laser, and recurrence was detected in 11 patients (3.27%). 9 Although the side effects were less in the KTP laser patients, our recurrence rate was higher.In both studies, the effectiveness of both laser types in the treatment of verrucae was high.However, we think that KTP laser treatment can be applied more easily because it does not require local anesthesia and causes very low pain.There are also publications reporting that patient satisfaction is higher due to low pain and low risk of post-treatment complications. 11,12eatment mechanism of PDL for warts is not clear.It is thought that this method is based on the specific destruction of superficial dilated capillaries in warts by selective photothermolysis. 135][16][17] Fichman et al, reported a clearance rate of 82.5% with PDL, which patients had previously been treated and "failed" other modalities, mainly cryotherapy. 18The variability of study results may be due to variation between the types of verrucae treated and PDL application techniques. 13It has been reported that it causes pain during and after the application, and purpura occurs within minutes and heals in 10-14 days. 13,19,20An average of 2.8 sessions with PDL were performed in 120 patients by Park et al. 13 Topical anesthetic was required due to pain.Recurrence was observed in six (15.7%) of 38 patients who completely recovered within the first 3 months, and in five more patients within the following period.Pain, scarring, and pigmentation changes have been reported during and after the procedure. 13We can say that the KTP laser is more effective than PDL, according to our results.There is no need for local anesthesia.Our recurrence rates are lower and side effects are less.
CO 2 laser with a wavelength of 10 600 nm are ablative lasers.Its beams cause nonselective thermal tissue damage and destruction. 21other treatment option of verrucae is CO 2 laser.Success rates of CO 2 laser have been reported between 64% and 71% in different case series.
Clinical improvement was classified as follows; • Complete recovery: complete disappearance of the lesion • Partial recovery: partial disappearance of the lesion • No recovery: no change in lesion • Exacerbation: enlargement of the lesion

• 2
points: mild pain • 3 points: moderate pain • 4 points: severe pain • 5 points: not to be tolerated Cosmetic outcomes at the 3rd month either normal skin (complete cosmetic recovery), pigmentary changes or scarring were evaluated.

tients scored 2 F I G U R E 2
points according to the pain scores.None of the patients needed local anesthesia and no severe pain developed during the applications.FI G U R E 1 Female patient, V. vulgaris before (A) and after (B) single session KTP; complete recovery at 3rd month followup.Male patient, a pair of V. plantaris lesions before (A) and after (B) single session KTP; complete recovery at 3rd month follow-up.
Demographic data and baseline clinical characteristics of patients.Distribution of patients and verrucae types.
3,21Postoperative pain, long recovery time, and scarring were common complications of CO 2 laser.Percentage of patients respond after each treatment.
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