Use of the alexandrite laser (755 nm, 100 nsec) for tattoo pigment removal in an animal model

Comparison of the safety and efficacy of low fluence Q-switched 1064-nm and conventional Q-Switched 755-nm lasers in the treatment of café-au-lait macules: A prospective self-controlled trial

BACKGROUND

Conventional high fluence Q-switched (HFQS) Alexandrite 755-nm are widely used in clinical café-au-lait macules (CALMs) treatment. There have been recent concerns regarding the efficacy and safety of low fluence Q-switched (LFQS) Nd: YAG 1064-nm lasers.

OBJECTIVE

To evaluate the efficacy and safety of the conventional HFQS and LFQS laser in the treatment of CALMs.

METHODS

Within 3 months, 20 patients underwent prospective self-controlled split-lesion treatments with HFQS once or twice depending on the recovery rate, and with LFQS six times biweekly. Then the more effective laser was selected for continued treatments. Efficacy outcomes were evaluated by a visual analog scale (VAS) biweekly during the comparative trail. Recovery process, side effects and recurrence were recorded during the trial and follow-up visit. Patient and physician preferences for laser selection were also recorded.

RESULTS

The average VAS scores of areas treated with HFQS and LFQS were 2.92 ± 0.86 and 2.93 ± 1.13, respectively (p > 0.05). The most significant efficacy change of LFQS was after the fourth laser treatment (VAS score: 1.82-2.37, p < 0.001). 11 lesions treated with LFQS and 7 with HFQS achieved an optimal treatment response (3.67 ≤ VAS ≤ 4). Three patients relapsed on one side (one on LFQS, two on HFQS) and five on both sides. Adverse effects included temporary hypopigmentation, hyperpigmentation, uneven pigmentation, and mottled hypopigmentation. Doctors thought 80% of patients were suitable for LFQS. 70% of patients preferred LFQS posttreatment.

CONCLUSIONS

The efficacy difference between the LFQS 1064-nm laser and HFQS 755-nm laser in treating CALMs in a 3-month comparative trial was statistically insignificant. LFQS is preferred by doctors and patients and is likely to help more patients achieve treatment efficacy than the HFQS within a short time, with fewer temporary adverse reactions, and a more even pigmentation. But it can cause mottled hypopigmentation. The LFQS had obvious lesion clearance after the fourth treatment.

The effect of the perfluorodecalin patch on particle emission and skin temperature during laser-induced tattoo removal

Laser-based procedures for tattoo removals are popular due to high efficacy and a relatively moderate insult. However, it often requires multiple sessions to achieve a satisfactory effect. The perfluorodecalin (PFD) patch utilizes an optical clearing agent to speed up the removal process and may decrease skin insult and harmful particles emission during treatment. This study assessed in pigs the effect of the PFD patch in connection with laser treatment of skin with and without tattoos to determine whether the PFD patch provides benefit in lowering thermal skin insult and particle emission during treatment. Skin temperature measured by infrared thermometer during laser treatment or shortly thereafter showed a significant (approximately 40%) decrease with the PFD patch in sites with tattoos. For laser-treated sites without tattoos, there was a significant decrease of particles observed with the PFD patch. In laser-treated sites with tattoos, a strong trend was seen (approximately a twofold decrease) but did not reach statistical significance due to high variability. The present data show that the PFD patch limits the increase in skin temperature produced with laser during treatment. Moreover, it decreases the emission of particles in sites without tattoos and is suggestive of a similar effect in sites with tattoos.

Laser tattoo removal: a review

BACKGROUND

Tattoos have played an important role in human culture for thousands of years, and they remain popular today. The development of quality-switched (QS) lasers has revolutionized the removal of unwanted tattoos.

OBJECTIVES

To thoroughly review the literature on laser tattoo removal pertaining to its history, its theoretical basis, the various devices used, potential adverse effects, and future developments.

MATERIAL AND METHODS

An extensive literature review of publications related to tattoo removal was conducted.

RESULTS

Reports exist demonstrating the efficacy of laser removal of different tattoo types, including professional, amateur, traumatic, cosmetic, and medical. The literature supports the use of different QS lasers for removal of tattoos. Some colors have a more-complete response using particular wavelengths.

CONCLUSION

QS lasers can effectively and safely remove different types of unwanted tattoos.

Laser transport through thin scattering layers

Many modern applications of lasers involve understanding the transport of radiation through thin layers. The interactions of continuous wave and pulsed lasers with skin in dermatological use related to surgery and cosmetic procedures are examples of such. These highly scattering thin layers in skin are best modeled by the Monte Carlo method. However, most traditional Monte Carlo models may inaccurately account for the presence of thin layers. As an example, the very thin epidermis, with its highly absorbing melanin, is known to influence the laser penetration significantly. If the Monte Carlo model is implemented without special features, then the results of the simulation will show incorrect effects of thin layers because the path length of most photons would be significantly larger than the layer thickness. As a result, the computed photon travel path length would simply not feel the presence of the layer. In this paper, we present numerical and algorithmic features for computation of radiation transport through thin layers. It is noted that, while Monte Carlo without special features smears the radiative effect of the layers, the refined technique indicates that layers have a great impact on the absorption of energy, especially if the layer properties are distinctly different from those of the adjacent layers. The results have significant implications in the study of diagnostic and therapeutic applications of lasers in biomedicine and surgery.

Removal of amateur blue-black tattoos in Arabic women of skin type (III-IV) with Q-switched alexandrite laser

BACKGROUND AND OBJECTIVES

Tattoos in Arabic society used to have a cosmetic importance on the face of females. These were usually amateur tattoos done by non-professional women in the tribe. Because Islam as a religion prohibited its practice and its application, people became concerned about removing the old tattoos by any means. Nowadays, laser is considered an effective method of tattoo removal. Here, we report our experience in the removal of tattoos in Arabic women of skin type III-IV using the Q-switched alexandrite laser.

STUDY DESIGN/MATERIALS AND METHODS

Twenty female subjects aged 35-50 years from similar racial and ethnic background with amateur tattoos were treated using the Q-switched alexandrite laser. Fluence threshold was determined and a spot test was made. Q-switched alexandrite laser with a fluence range 4.0-7.5 J/cm(2) (mean 6.05) was used at 6-12-week intervals. Total treatment numbers ranged from three to six sessions (mean 4.15) with single-pulse technique application.

RESULTS

More than 95% lightening was achieved in five patients after three to six sessions at fluence range of 6-7.5 J/cm(2) and > 75% lightening in 10 subjects after three to six sessions of treatment at fluence range of 4-7.5 J/cm(2). Pinpoint bleeding was observed in one case but no pigmentary alteration or scarring was seen.

CONCLUSION

Tattoo pigment removal by Q-switched alexandrite laser is an effective method in skin type (III-IV) with minimal side effects, which gives high patient satisfaction.

The use of Q-switched alexandrite laser (755 nm, 100 ns) for eyeliner tattoo removal

BACKGROUND

Eyelid tattooing for cosmetic reasons has increased in the past few years, and unsatisfied customers may request pigment removal. Q-switched laser systems have been useful in these cases.

OBJECTIVE

To evaluate the clinical result of a patient with a bluish-black eyelid tattoo treated with Q-switched alexandrite laser.

METHODS

Threshold fluence was determined and a spot test made on the first visit. Treatment was with QSAL, with a fluence range of 6.75-7.50 J/cm2 (mean fluence 7.125 +/- 0.26) and overlapping +/- 10% at 4-week intervals.

RESULTS

The eyeliner tattoo was not completely removed after five treatments with QSAL, but noticeable pigment lightening was obtained. No side effects were seen.

CONCLUSIONS

Q-switched alexandrite laser may be a useful device to remove the bluish-black pigment used in cosmetic eyeliner tattoo.

Cosmetic tattoo refractive to Q-switched alexandrite laser

BACKGROUND

Lip tattooing is a common cosmetic technique not exempt from certain risks and which may lead an unsatisfied customer to seek tattoo elimination.

OBJECTIVE

To assess the clinical outcome of a patient with a brownish-colored cosmetic lip tattoo after treatment with the Q-switched alexandrite laser (QSAL).

METHODS

Two sites were tested using the pigment lesion dye laser (PLDL) and QSAL. The patient received 10 monthly sessions with QSAL, with an average fluence of 6.925 J/cm2. The double and triple shot technique was applied.

RESULTS

The brownish pigmentation turned black after the PLDL and QSAL tests. Epidermal splattering and bleeding made a fluence increase with QSAL inadvisable. Treatment was unsuccessful.

CONCLUSIONS

PLDL and QSAL may induce a photochemical alteration in brownish pigment. Factors that may contribute to the poor response of a cosmetic lip tattoo to QSAL treatment are related to pigment characteristics and laser parameters.

Lasers in dermatology: four decades of progress

Advances in laser technology have progressed so rapidly during the past decade that successful treatment of many cutaneous concerns and congenital defects, including vascular and pigmented lesions, tattoos, scars, and unwanted hair-can be achieved. The demand for laser surgery has increased substantially by patients and dermatologists alike as a result of the relative ease with which many of these lesions can be removed, combined with a low incidence of adverse postoperative sequelae. Refinements in laser technology and technique have provided patients and practitioners with more therapeutic choices and improved clinical results. In this review, the currently available laser systems with cutaneous applications are outlined, with primary focus placed on recent advancements and modifications in laser technology that have greatly expanded the cutaneous laser surgeon's armamentarium and improved overall treatment efficacy and safety.

Laser eradication of pigmented lesions and tattoos

Laser treatment of pigmented lesions can be a rewarding experience when appropriate lesions are treated. Accurate diagnosis of pigmented lesions is needed before treatment. In some lesions, adjuvant topical therapy is greatly beneficial, and for others it may be the only option. The treatment of melanocytic nevi is controversial but worth pursuing. All tattoos respond well to Q-switched lasers; the appropriate wavelength depends on the color of ink. Amateur and traumatic tattoos clear readily with laser treatment. Cosmetic tattoos should be approached with caution. In addition, the use of laser-responsive ink and higher-powered or shorter-pulsed (picosecond) lasers may further enhance the ability to treat tattoos.

Successful treatment of treatment-resistant laser-induced pigment darkening of a cosmetic tattoo

BACKGROUND AND OBJECTIVE

Cosmetic tattoo removal has a reported risk of immediate pigment darkening when treated with a high energy, nanosecond pulsed-laser system. Surgical treatment options for this reaction are limited and carry significant risk of scarring and permanent pigment alterations. This report describes the response of a resistant Q-switched ruby laser-induced cosmetic tattoo ink darkening to multiple treatments with the Q-switched alexandrite laser and Q-switch Nd:YAG laser and textural improvement with the UltraPulse CO(2) laser.

STUDY DESIGN/MATERIALS AND METHODS

A woman with Q-switched ruby laser-induced pigment darkening of a cosmetic tattoo of the upper lip resistant to four further treatments with the ruby laser and two chemical peels received a total of 26 treatments with the Q-switched alexandrite and Nd:YAG lasers and a single treatment with the UltraPulse CO(2) laser, most treatments being done at monthly intervals.

RESULTS

Treatment of the affected areas with the Q-switched alexandrite and Nd:YAG lasers resulted in complete clearing of the pigment without scarring, but revealed some preexisting textural changes. Use of the UltraPulse CO(2) laser smoothed the surface irregularities.

CONCLUSION

The Q-switched pigment lasers are a useful modality for treating this pigment darkening reaction. As in this case, multiple treatment sessions with the laser may be necessary but the pigment can be expected to clear eventually without scarring. Any textural changes may be blended with the UltraPulse CO(2) laser with further improvement.

Effective treatment of traumatic tattoos with a Q-switched Nd:YAG laser

BACKGROUND AND OBJECTIVE

It is well known that the Q-switched Nd:Yag (QSNd:YAG) laser works well in the treatment of blue-black tattoos and benign pigmented lesions. It is less well known that this laser can also treat traumatic tattoos after accidents.

MATERIALS AND METHODS

Twelve patients with traumatic tattoos were treated with a QSNd:YAG laser, 1064 nm.

RESULTS

Gravel, mascara, high explosives, and older tattoos responded best with total clearance after 2-5 treatments. Hard materials such as asphalt, amalgam, and metal needed 6-11 treatments, and there was not always complete clearance. Transcient hypopigmentation but no scarring was seen.

CONCLUSION

QSNd:YAG laser treatment of traumatic tattoos is effective, atraumatic, and a good alternative to mechanical dermabrasion or other conventional therapies.

Response of associated oral soft tissues when exposed to Argon laser during polymerization of dental resins

BACKGROUND AND OBJECTIVE

Polymerization of dental resins with Argon laser produces restorations with improved physical properties when compared to conventional visible-light polymerization techniques. However, the possibility of damaging adjacent soft tissues has not been addressed.

STUDY DESIGN/MATERIALS AND METHODS

In this study, Argon laser (488/514 nm) was used for the polymerization of composite resins to determine effects on the parakeratinized gingiva adjacent to both restored and unrestored teeth in six dogs, using 10-, 20-, and 30-second polymerization exposures.

RESULTS

Gingival tissues removed at 24 hours, 72 hours, or 5 days revealed desiccated, disrupted, hyalinized connective tissue. Tissues exposed for 10 seconds showed minimal change. This minimal degree of change was most evident at 72 hours and returned to normal limits at 5 days. The 20-second exposure produced alterations evident through all time periods. Tissues exposed for 30 seconds exhibited necrosis, severe disruption, and vessiculation, which was still unresolved at 5 days.

CONCLUSION

This study demonstrates that clinically relevant Argon laser exposure (10 seconds) of parakeratinized gingiva adjacent to teeth undergoing restoration does not cause lasting damage.

Clinical features of Ota's naevus in Koreans and its treatment with Q-switched alexandrite laser

Ota's naevus is a fairly common pigmentary disorder in Asians. Recently, encouraging results in the treatment of Ota's naevus have been obtained, but most of these concerned the white skins of Caucasian patients. Our purpose was to examine the clinical features of Ota's naevus in Koreans and to assess the clinical outcomes and histological changes induced by a Q-switched alexandrite laser at 755 nm. Eighty-seven Koreans with Ota's naevus were studied; the peak age of onset was during the first decade and adolescence. The infraorbital area was the most frequent site and black or dark brown colours predominated. Improvements were achieved in 52 patients (77%). Better results were obtained in unilateral lesions and patients who received a greater number of treatments. Mild hyperpigmentation after treatment was noticed in 14 patients and mild hypopigmentation in eight patients. However, all of these were reversed in time. Hypertrophic scarring or secondary infection did not occur. The histology of laser-irradiated lesions showed selective thermal damage of melanocytes in the upper dermis and the elimination of upper dermal pigmentation. Our clinical data demonstrate the usefulness of the Q-switched alexandrite laser for the treatment of Ota's naevus in brown skin.

Use of Q-switched alexandrite laser (755 nm, 100 nsec) for removal of traumatic tattoo of different origins

BACKGROUND AND OBJECTIVES

Q-switched laser systems have been used for removal of tattoo-related carbon, graphite, and other particles. We assessed elimination of traumatic tattoos of different origin with Q-switched alexandrite laser in nine patients.

STUDY DESIGN/MATERIALS AND METHODS

Fluence threshold was determined and a spot test was made. Q-switched alexandrite laser, with a fluence range 4.5-8.0 J/cm(2) (mean, 7.16 +/- 1.18), was used at 4-5-week intervals. Total treatment ranged from 3-12 sessions (mean, 6.1 +/- 3.6 sessions). Double-pulse technique was used in black/black-bluish areas, but single-shot was applied to slate-gray pigment.

RESULTS

More than 95% lightening was achieved in five patients after 5.2 +/- 2.3 sessions, and >75% lightening in six subjects after 6.1 +/- 3.1 sessions of treatment. Blacktop, surgical pen, and gravel tattoos presented a better response than gunpowder/fireworks tattoos (>95% vs. 68.7 +/- 23.9% clearance), or tattoos of unknown origin (>95% vs. 62.5 +/- 53% clearance). Epidermal splattering and pinpoint bleeding were observed in one case. No pigmentary alteration or scarring was seen.

CONCLUSION

The Q-switched alexandrite laser is a useful system for removal of traumatic tattoos of diverse origin. The best response (>95% clearance) was achieved in blacktop, surgical pen, and gravel tattoos, although an acceptable degree of lightening may be obtained in tattoos due to gunpowder or fireworks.

Use of the Q-switched alexandrite laser (755 nm, 100 nsec) for eyebrow tattoo removal

BACKGROUND AND OBJECTIVE

Permanent tattooing for cosmetic reasons has increased in recent years; as a consequence, there has been an increase of requests for pigment removal due to complications or undesired results. The Q-switched alexandrite laser has been found useful in removing black exogenous pigment, which is the most popular color in eyebrow enhancement. We report the case of a patient with black-pigment eyebrow cosmetic tattoo after treatment with the Q-switched alexandrite laser.

STUDY DESIGN/MATERIALS AND METHODS

Treatment conditions included 755-nm wavelength, 100 +/- 10-nsec pulse width, and 3-mm spot size. Fluence threshold was determined, and a spot test was made at the first visit. Single impact technique with 10% overlapping was applied to the whole tattoo. Five treatments were performed with a mean fluence of 7 J/cm(2).

RESULTS

Complete pigment removal was achieved after five sessions. Superficial bleeding and vesicle formation was observed.

CONCLUSIONS

Eyebrow tattooing can be treated efficiently with the use of the Q-switched alexandrite laser when black pigment has been used for cosmetic reasons.

Laser treatment of tattoos

All three Q-switched laser systems can effectively remove most tattoos with minimal scarring or other adverse sequelae. Despite advances in laser technology, all tattoos cannot be completely eliminated, and several wavelengths remain necessary to optimally treat multicolored tattoos. The major advantage of Q-switched laser irradiation to effect tattoo removal is the low risk of scarring associated with treatment. Limitations include the need for multiple treatment sessions, minimal to incomplete responses in some cases, and the possibility of pigmentary and textural changes. Research continues in an effort to perfect laser removal of tattoos.

Lasers in dermatology

The use of dermatologic laser therapy is rapidly expanding. Thirty years of experience has produced advances in the technology, techniques, and therapeutic efficacy of dermatologic lasers. The original lasers have been improved and modified, and new types of lasers have expanded the dermatologist's therapeutic repertoire. Extensive research has provided a greater understanding of the skin's clinical and histologic response to laser treatment. This has allowed dermatologists to expand their therapeutic options and techniques and to improve clinical outcome.

The adjuvant use of macrophage colony stimulating factor in tattoo removal using laser surgery

Tattoos are acquired pigmented lesions of the skin that may be removed with laser surgery. Following laser treatment, macrophages engulf the altered pigment. The activity of macrophages can be influenced by macrophage colony-stimulating factor. In order to evaluate the potential adjunctive use of macrophage colony-stimulating factor in tattoo removal using laser surgery, a prospective study, initially in an animal model, to serially evaluate the clinical and histopathologic clearing of tattoo pigment following laser surgery at variable macrophage colony-stimulating factor dose concentrations and injection schedules, could be performed. Since the clearing of tattoo pigment following laser surgery is influenced by the presence of macrophages at the site of treatment, and since macrophage colony-stimulating factor influences macrophage activity, it is logical to hypothesize that the adjuvant use of this cytokine to recruit additional macrophages could expedite the removal of tattoo pigment following laser surgery.

Treatment of nevus of Ota by the Q-switched alexandrite laser

BACKGROUND

The Q-switched alexandrite laser (755 nm, 100 nanoseconds) selectively targets and destroys cutaneous pigment such as that found in dermal pigmented lesions and tattoos. The nevus of Ota is a benign dermal melanocytic lesion, which, due to its large size and periocular location, has been notoriously difficult to treat. Utilizing the principles of selective photothermolysis, the alexandrite laser could effect an excellent treatment for nevus of Ota.

OBJECTIVE

To report the effectiveness of the Q-switched alexandrite laser in treating nevus of Ota.

METHODS

Seven patients with nevus of Ota were treated with the Q-switched alexandrite laser (755 nm, 100 nanoseconds) with energy densities ranging from 4.75 to 7.0 J/cm2 at 8-12-week intervals. Response to therapy was evaluated through independent observation and rating of sequential photographs by two blinded observers. Histologic examinations of lesional skin biopsies before and after completion of laser treatments were performed.

RESULTS

An average of two laser treatments were required to effect an average clinical improvement of 50%. Five patients showed 100% lesional clearance after an average of five treatments. No scarring, textural changes, or pigmentary side effects were observed in treated skin. Histology of laser-irradiated lesions revealed elimination of upper dermal pigmentation without epidermal disruption, and rare melanophages and pigmented spindle cells in the deep reticular dermis. No lesional recurrences were observed up to 1 year following treatment.

CONCLUSION

The Q-switched alexandrite laser can effectively eliminate nevus of Ota without untoward side effects, such as scarring.

Q-switched alexandrite laser treatment (755 nm) of professional and amateur tattoos

BACKGROUND

Several laser techniques have been proposed for the removal of decorative tattoos. The lasers that have been used most successfully are Q-switched red or near-infrared systems because of their ability to target tattoo pigment selectively with minimal risk of scarring or permanent pigmentary changes.

OBJECTIVES

The objectives of this study were to determine the clinical effectiveness of the newest Q-switched system, the alexandrite laser, in removing amateur and professional tattoos and to observe side effects.

METHODS

Twenty-four multicolored professional tattoos and 18 blue-black amateur tattoos were treated with the Q-switched alexandrite laser (755 nm, 100 nsec) at 2-month intervals until total clearing was achieved. The 510 nm pulsed dye laser was used to treat tattoos that contained red pigment.

RESULTS

Professional tattoos required an average of 8.5 alexandrite laser treatments for total clearance, whereas only 4.6 treatments were necessary to remove amateur tattoos. Red tattoo pigment was successfully treated with an average of two 510 nm pulsed dye laser sessions. No scarring or long-standing pigmentary changes were seen in laser-irradiated skin.

CONCLUSION

The Q-switched alexandrite laser is highly effective in removing multicolored professional and amateur tattoos without adverse sequelae. The 510 nm pulsed dye laser was useful in eliminating red tattoo pigment.

The Q-switched Alexandrite laser's effects on tattoos in guinea pigs and harvested human skin

BACKGROUND

Developmental work in tattoo removal is currently carried out in animal models whose skin has different optical and mechanical properties from human skin.

OBJECTIVE

To observe laser effects on tattoos in a new human skin model and that of in vivo guinea pig skin.

METHODS

A comparison of the efficacy of the Q-switched Alexandrite laser (750 nm, 100-120 nanoseconds) in tattooed harvested human skin and guinea pig skin was performed. Visual assessments as well as histologic and electron microscopy evaluation before and after treatment are reported.

RESULTS

Mild to moderate clearing of black tattoo pigment, as judged by visual assessment, was found after one laser treatment in both the in vitro human skin model and guinea pig skin. Blue and green ink showed similar results to black ink in human skin whereas red and yellow ink did not respond in our model.

CONCLUSION

Possible mechanisms of tattoo lightening and the usefulness of the in vitro human skin model are discussed.