1 PRACE ORYGINALNE / Original articles Dermatologia Kliniczna 2009, 11 (4): ISSN Copyright 2009 Cornetis; Utilization of Nd:YAG Laser (1064 nm) in the treatment of dermatosis papulosa nigra in some Sudanese patients Shaza Mohammed Yousif, Nafie A. Al-Muslet, Nagi Zarif Malati Institute of Laser Sudan University of Science and Technology, Khartoum/Algerian, Republic of Sudan Address for correspondence: Nafie A. Al-Muslet Institute of Laser Sudan University of Science and Technology the west campus P.O. Box (407) Khartoum / Algerian, Republic of Sudan; tel.: , Abstract Introduction: Skin of phototypes IV to VI according to Fitzpatrick represents the majority of the world s population. Clinically, the features of photoaging in African can include fine wrinkling, mottled pigmentation, and dermatosis papulosa nigra (DPN). All studies have confirmed the effectiveness and low risk of complication associated with use of Nd: YAG laser in dark skin patients. Objectives: This study aimed to detect the effectiveness of Nd: YAG laser, 1064 nm, with specific laser parameters, in the treatment of dermatosis papulosa nigra (DPN) in some Sudanese patients. Material and methods: Twenty patients, clinically diagnosed as cases of dermatosis papulosa nigra, were selected from different dermatology clinics in Khartoum state and were considered as study population. Nd: YAG laser, with 1064 nm wavelength, was used in this study. The laser parameters were: non-contact applications of bare fiber, power of 25 Watt and duty cycle of 0.2 second. The number of exposure intervals delivered per lesion was chosen according to the size of papules. The data was analyzed using SPSS 15.0, and p-value of p<0.05 had been used. Results: Relationship of the treatment response and Northern tribes was found statistically relevant (p<0.05). Three and six weeks after the last session, evaluation of patients response was as following: Excellent response in 17 patients (85%), Very good in 3 patients (15%), Good (0.0%), Bad (0.0%), No response (0.0%). Conclusions: This study proved that the use of Nd: YAG laser 1064 nm, with certain parameters could achieve excellent or very good results in all patients. Key words: Nd:YAG laser, dermatology, laser therapy, dermatosis papulosa nigra Streszczenie Wprowadzenie: Większość ludzi na świecie ma skórę o fototypie od IV do VI wg klasyfikacji Fitzpatricka. Klinicznie, do cech starzenia się skóry wynikającego z procesów zależnych od promieniowania słonecznego (photoaging) w Afryce, należy zaliczyć: drobne zmarszczki, plamiste pigmentacje oraz dermatosis papulosa nigra (DPN). Liczne badania potwierdziły skuteczność i bezpieczeństwo zabiegów wykonywanych przy użyciu lasera Nd:YAG u czarnoskórych pacjentów. Cel badań: Ocena skuteczności zabiegów wykonywanych przy użyciu lasera Nd:YAG (1064 nm) w leczeniu dermatosis papulosa nigra u pacjentów z Sudanu. Materiał i metody: Do badań włączono 20 pacjentów z kilku klinik z prowincji Khartoum, u których rozpoznano dermatosis papulosa nigra. Zabiegi wykonywano laserem Nd:YAG, emitującym promieniowanie o długości fali 1064 nm o następujących parametrach: końcówka bezkontaktowa, moc 25 Watt, długość impulsu 0.2 s. Liczba przerw podczas zabiegów zależała od wielkości usuwanej zmiany. Wyniki były analizowane za pomocy oprogramowania SPSS 15.0, przyjęto p-value dla p<0.05. Wyniki: Wykazano statystycznie istotny związek w odpowiedzi na leczenie jedynie u pacjentów pochodzących z plemion północnego Sudanu (p-value<0.05). Trzy lub sześć tygodni po ostatniej sesji laseroterapii oceniono skuteczność leczenia na: Wspaniała odpowiedź u 17 pacjentów (85%), Bardzo dobra u 3 pacjentów (15%), Dobra (0.0%), Zła (0.0%), Bez odpowiedzi (0.0%). Wnioski: Przeprowadzone badanie wykazało, że w leczeniu dermatosis papulosa nigra zabiegi przy użyciu lasera Nd:YAG (1064 nm) były bardzo skuteczną metodą terapeutyczną u wszystkich pacjentów. Słowa kluczowe: laser Nd:YAG, dermatologia, terapia laserowa, dermatosis papulosa nigra Introduction Clinically, the features of photoaging in African can include: fine wrinkling, mottled pigmentation, and dermatosis papulosa nigra (DPN). DPN is a multiple, small, hyper pigmented, flattened, or verrucous asymptomatic papules that measure 1-5 mm in diameter, common among blacks (1). It is a benign cutaneous condition, classified within the group of epithelial nevi and by some authors, considered as small seborrhoeic keratoses (2, 3). DPN can be graded (G) as follows (4): GI (mild) less than 10 spots, GII (moderate) 10 to 50 spots, GIII (severe) more than 50 spots. The small elevations of the skin of DPN can sometimes develop thicker scaling but, crusting, and ulceration do not occur (4, 5). The pathophysiology of DPN is not known. It is likely to be genetically determined, with 40-54% of patients having a family history of involvement. It is believed to be caused by a nevoid developmental defect of the pilosebaceous follicle (6). Histopathology shows the appearance of a seborrhoeic keratosis, they display hyperkeratosis, irregular acanthosis, keratin-filled invaginations of the epidermis (horn cysts), and marked hyperpigmentation of the basal layer. Although most lesions are of the acanthotic type and show thick interwoven tracts of epidermal cells, they may have a reticulated pattern in which the tracts consist of a double row of basaloid cells (2, 6). 197
2 Utilization of Nd:YAG Laser (1064 nm) in the treatment of dermatosis papulosa nigra in some Sudanese patients Dermatologia Kliniczna 2009, 11 (4) 198 The incidence of DPN, as well as the number and size of individual lesions, increases with age. It usually begins in adolescence and is rare under the age of 7 years. Data pertaining to the international frequency of DPN are insufficient. It affects up to 35% of the African American population. Blacks with a fair complexion have the lowest frequency of involvement. Females are affected more frequently than males (2, 5). The applied removal methods of lesions are: freezing (cryosurgery), scraping (curettage), burning (electrocautery) and laser treatment (4). Locally destructive treatment can result in complications, which include increased and decreased pigmentation, scarring and keloid formation. Nd:YAG laser has recently been reported to achieve excellent cosmetic results with minimum complication. Even though other lasers have been used successfully, like 532 nm diode-pumped laser, carbon dioxide (ultra pulse) laser, 585 nm pulsed dye laser and Nd:YAG Q-switched laser (5). Objectives This study aimed A. To detect the effectiveness of Nd:YAG laser, 1064 nm, with specific parameters, in the treatment of dermatosis papulosa nigra in some Sudanese patients. B. To determine the possible association between the ef fective ness of Nd:YAG laser in the treatment of dermatosis papulosa nigra and demographic data. Material and methods Patients Twenty patients, clinically diagnosed as cases of dermatosis papulosa nigra, were selected for this study from different dermatology clinics in Khartoum state and were considered as study population. Selected patients were: Over 18 years of age. Able to give informed consent. Desire removal of lesions. Willing to come back for one week, three and six weeks follow-up. Willing to fill out post operative questionnaire. With at least 4 lesions less than 7 mm. Diagnosis of DPN. EMLA cream was used one hour pre-operatively as topical anesthesia at site of lesion. Elovera sun block lotion SPF 30 was used post-operatively as topical sun screen. The patients included in the study were photographed before the treatment, and at intervals of one week and three weeks after the last session. All patients were requested to participate voluntarily, and a written informed consent was done with ethical clearance from patient himself, before being enrolled in the study. They were informed about the possible side effects and the hazards of laser therapy. Confidentiality of the patients was maintained For each patient, a confidential record of personal data was made. This includes: serial number, date of operation, name, age, sex, tribe, occupation, address as well as detailed information about the medical history of the patient, morphology, site, duration and classification of the lesion. The details are listed in table I. Patients grouping Patients were classified in three groups according to the number of lesions: Group I; less than 10 spots, Group II; 10 to 50 spots and GIII; more than 50 spots. The laser medical system Nd:YAG laser (neodymium-yttrium-aluminum-garnet), model Fibertom 5100, with 1064 nm wavelength, manufactured by Dornier MedTech (Germany), was used in this study. Nd:YAG laser parameters used were: non-contact applications of bare fiber, power of 25 Watt, and exposure interval (duty cycle) of 0.2 second. The number of exposure intervals delivered per lesion was chosen according to the size of papules. The function of the Nd-YAG laser in this study was to coagulate the melanin and concerned blood vessels in the lesions. It emits wavelength of 1064 nm which penetrates to 1600 µm and is well absorbed by melanin and blood. The absorbed laser power is converted into heat, causing coagulation of the targeted vessels. Nd:YAG laser procedures All patients were sharing the standard mode, single pulse, with exposure interval (duty cycle) of 0.2 second, power of 25 Watt, power density of 3125 Watt/cm 2, and spot size of cm 2. But they differ in the exposure time and number of sessions regarding the irradiated areas. Lasing procedure The hand of the fiber was held close to the lesion in non contact mode. The lasing switch was turned on. The foot switch was pressed repeatedly and different numbers of exposure intervals were applied point by point on the lesion and then (popcorn like) sound was heard or blanching of color was seen. Sessions were done on one week intervals. Postoperative care Sun block lotion was prescribed for daily use when exposed to sun light. After the last session, one week and three weeks follow up appointments were given to the patient to evaluate the results. A post-operative photo was taken from the site of the lesion at one week and three weeks after the last session. Evaluation of the results For the evaluation of the treatment response, 10% was given for the response of the treatment for every element of evaluation. Ten elements of evaluation are considered below. Excellent response achieved when no element for evaluation was developed, very good response achieved when the percentage of elements for evaluation was 20%, good response achieved when the percentage was 40%, poor response achieved when the percentage was 60% and bad response achieved when the percentage of elements for evaluation was >60%. Elements for evaluation of the treatment response: 1. Prolonged erythematic lasting more than 24 hours. 2. Purpura lasts >14 days. 3. Hypopigmentation lasts >3 weeks. 4. Atrophic or hypertrophic scaring. 5. Keloid formation. 6. Postoperative blistering. 7. Delayed wound healing. 8. Wound infection. 9. Residual tissue. 10. Patients satisfaction <70%. Data analysis The data was entered in spread sheets and analyzed using SPSS 15.0 and p-value of p < 0.05 had been used.
3 Results and discussion Table I: Background data of patients Tabela I: Dane opisujące pacjentów Sex Płeć Age group (Year) Grupa wiekowa (wiek w latach) Tribe Plemię (pochodzenie) Family history of similar condition Występowanie rodzinne Consanguinity Stopień pokrewieństwa Background data of patients Dane opisujące pacjentów Female / Kobiety 18 (90%) Man / Mężczyźni 2 (10%) (60 %) (40 %) >60 0 (0%) N / z północy 16 (80%) E / ze wschodu 2 (10%) W / z zachodu 2 (10%) S / ze wschodu 0 (%) Positive / Tak 20 (100%) Negative / Nie 0 (0%) First degree / I stopnia 4 (20%) Second degree / II stopnia 6 (30%) Non / Żadne 10 (50%) For all patients, the morphology of the lesions, site, duration and classification are illustrated in table II. Table II. Tab. II. Dane kliniczne Duration of lesions (Year)/Czas od wystąpienia zmian (w latach) Morphology Morfologia zmian Site of lesion Umiejscowienie zmian Classification Klasyfikacja Dane kliniczne Longest / Najdłuższy 20 Shortest / Najkrótszy 1 Mean duration / Średni czas 1.35 Papule / Grudki 16 (80%) Papule & verrucae / Grudki i powierzchnie brodawkujące 4 (20%) Face / Twarz 9 (45%) Face & neck / Twarz i szyja 9 (45%) Face, neck, upper chest & back / Twarz, szyja, górna część tułowia i plecy 2 (10%) Grade I / Stopień I 1 (5%) Grade II / Stopień II 9 (45%) Grade III / Stopień III 10 (50%) Response of DPN to Nd:YAG laser The response was achieved in all patients, after one, two or three sessions. Relationship of the treatment response and Northern tribes was found with (p value <0.05), no other relationship between treatment response and other demographic data was found. Three and six weeks after the last session, evaluation of patients was: Excellent response in 17 patients (85%) Very good response in 3 patients (15%) Good response (0.0%) Bad response (0.0%) Poor response (0.0%) No response (0.0%) Almost all patients experienced transient erythematic not more than 24 hours. Fifteen patients (75.0%) developed transient hypopigmentation which faded out within three weeks after treatment. Eight patients (40.0%) developed hyperpigmentation, in only half of them (four patients) the hyperpigmentation resolved at six weeks. In literature, hyperpigmentation is almost always transient and fades out from three to four months (7, 8). The figures 1-3 show a comparison for some cases before, and three weeks after laser treatment. 199
4 Yousif S.M., Al-Muslet N.A., Malati N.Z. Utilization of Nd:YAG Laser (1064 nm) in the treatment of dermatosis papulosa nigra in some Sudanese patients 200 Fig. 1a. Before laser treatment Ryc. 1a. Przed laseroterapią Fig. 1b. Three weeks after treatment Ryc. 1b. Trzy tygodnie po laseroterapii Fig. 2a. Before laser treatment Ryc. 2a. Przed laseroterapią Fig. 2b. Three weeks after treatment Ryc. 2b. Trzy tygodnie po laseroterapii Fig. 3a. Before laser treatment Ryc. 3a. Przed laseroterapią Fig. 3b. Three weeks after treatment Ryc. 3b. Trzy tygodnie po laseroterapii Dermatologia Kliniczna 2009, 11 (4)
5 Conclusions This study proved that the use of Nd:YAG laser is preferable in treating DPN, because it is easy to perform, the response was excellent in majority of treated patients (85.0%) and very good in the rest of them (15.0%) and the complications were minimal and almost transient. Relationship of the treatment response and Northern tribes was found statistically relevant (p value <0.05), which was not found in other demographic data. References 1. Elsaie M.L., Lloyd H.W.: Latest laser and light-based advances for ethnic skin rejuvenation. Indian J. Dermatol., 2008, 53, Nowfar-Rad M., Fish F.: Dermatosis papulosa nigra. Feb Schweiger E.S., Kwasniak L., Aires D.J.: Treatment of dermatosis papulosa nigra with a 1064 nm Nd:YAG laser: report of two cases. J. Cosmet. Laser Ther., 2008, 10, Bolognia J.L.: Dermatosis papulosa nigra. New York: Mosby, 2003, nigra sign sandsymptoms.htm, 5. Mark D.: Dermatosis papulosa nigra. 6. Wolff K., Johnson R.A., Suurmond R.: Color Atlas and Synopsis. McGraw- -Hill. 5 th ed., 2005; chapter five: Brown C.W. Jr.: Complications of Dermatologic Laser Surgery. (cited May 2009). 8. Lapidoth M., Shafirstein G., Ben Amitai D., Hodak E., Waner M., David M.: Reticulate erythema following diode laser-assisted hair removal: a new side effect of a common procedure. J. Am. Acad. Dermatol., 2004, 51, Received: Approved: