Q-switched Ruby Laser Treatment Research Articles

Thermal distribution and response in Q-switched ruby laser treatment for oculodermal melanosis (Nevus of Ota)

Aim: A clinically useful treatment laser must generate stable and precise energy of low diffusivity. This study assessed the photothermal response of a Q-switched ruby laser (QSRL) in the treatment of oculodermal melanosis (Nevus of Ota).

Synergy Effect of Combination of Fractional CO2 and Fractional Q-switched Ruby Laser Treatment for Skin Rejuvenation

Synergy Effect of Combination of Fractional CO2 and Fractional Q-switched Ruby Laser Treatment for Skin Rejuvenation

Fractional CO2 laser is as effective as Q-switched ruby laser for the initial treatment of a traumatic tattoo

Background and objective: Q-switched laser treatments are considered the standard method for removing both regular and traumatic tattoos. Recently, the removal of tattoo ink using ablative fractional lasers has been reported. Ablative fractional CO2 laser and q-switched ruby laser treatments were used in a split-face mode to compare the safety and efficacy of the two types of laser in removing a traumatic tattoo caused by the explosion of a firework. Study design/Patients and methods: A male patient suffering from a traumatic tattoo due to explosive deposits in his entire face was subjected to therapy. A series of eleven treatments were performed. The right side of the face was always treated using an ablative fractional CO2 laser, whereas the left side was treated only using a q-switched ruby laser. Results: After a series of eleven treatments, the patient demonstrated a significant lightening on both sides of his traumatic tattoo, with no clinical difference. After the first six treatments, the patient displayed greater lightening on the right side of his face, whereas after another five treatments, the left side of the patient's face appeared lighter. No side effects were reported. Conclusions: In the initial stage of removing the traumatic tattoo, the ablative fractional laser treatment appeared to be as effective as the standard ruby laser therapy. However, from the 6th treatment onward, the ruby laser therapy was more effective. Although ablative fractional CO2 lasers have the potential to remove traumatic tattoos, they remain a second-line treatment option.

Effectiveness of combined pulsed dye and Q-switched ruby laser treatment for large to giant congenital melanocytic naevi

There is no consensus on the most appropriate treatment for patients with large to giant congenital melanocytic naevi (CMN) because of the risk of melanoma development. Surgical excision followed by skin grafting or expanded skin coverage may cause unfavourable scarring. There is a balance to be achieved between minimizing the disfiguring appearance and the risk of malignant change. The pulsed dye laser (PDL) is commonly used for vascular lesions and is highly absorbed by melanin and haemoglobin. Its pulse duration is longer than that of Q-switched ruby lasers (QsRL), which can have nonspecific photothermolytic effects on surrounding nonpigmented naevus cells. To investigate the effectiveness of combined treatment with the PDL and QsRL for large to giant CMN. Six patients with large to giant CMN were enrolled in this study. Treatment consisted of one pass of PDL treatment followed by one pass of QsRL treatment. Multiple rounds of treatment were applied to all patients. All patients responded to this combined regimen, and the lesional colour was effectively reduced. The mean number of rounds of laser treatment required to achieve skin lightening was 7·7. No patients suffered severe hypertrophic scarring. No cases of recurrence or malignant transformation were observed. The histological results from the patient who underwent the most laser therapy in this study showed a remarkable reduction in the number of melanocytic naevus cells after treatment. This technique may enable the removal of most of the pigmented lesion and melanocytic naevus cells with minimal scarring.

Qスイッチルビーレーザーによる太田母斑の10年間の治療成績(第3報) —特に副作用としての脱色素斑の発生し易い条件の検討—

Qスイッチルビーレーザーによる太田母斑の10年間の治療成績(第3報) —特に副作用としての脱色素斑の発生し易い条件の検討—

Efficacy of 694-nm Q-Switched Ruby Fractional Laser Treatment of Melasma in Female Korean Patients

Melasma is a common acquired symmetrical hypermelanosis of sun-exposed areas of the skin. Although the classical Q-switched ruby laser (QSRL) has been used successfully for the removal of tattoos and for the treatment of cutaneous pigmented lesions, its efficacy for melasma remains controversial. We used repeat low-dose fractional QSRL treatment for melasma and analyzed the clinical results. Fifteen Korean women with melasma were enrolled. Each patient received six low-dose fractional QSRL treatments to the face at 2-week intervals. Two investigators independently evaluated Melasma Area and Severity Index (MASI) scores before each session and 4 and 16 weeks after the final session. The intensities of pigmentation and erythema were assessed by measuring skin reflectance using a tristimulus color analyzer. Mean MASI score decreased from 15.1 ± 3.3 before treatment to 10.6 ± 3.9 16 weeks after the final treatment. The lightness of pigmentation (L-value) increased from 56.6 ± 3.5 before treatment to 59.9 ± 2.8 16 weeks after the final treatment. Multiple treatment sessions of low-dose fractional QSRL may be an effective strategy for the treatment of dermal or mixed-type melasma.

A Prospective Randomized Controlled Study of Oral Tranexamic Acid for Preventing Postinflammatory Hyperpigmentation After Q-Switched Ruby Laser

Postinflammatory hyperpigmentation (PIH) is the most common skin complication in Asians after invasive cosmetic treatments. To determine whether oral tranexamic acid (TA) reduces the incidence of PIH after Q-switched ruby laser (QSRL) treatment. Thirty-two Japanese women underwent QSRL treatment for senile lentigines on the face. They were randomly divided into two groups that did (n=15) and did not (n=17) receive oral TA treatment (750 mg/d) for the first 4 weeks after QSRL treatment. Nineteen participants had melasma-like maculae at baseline. Clinical and colorimetric assessments were performed at baseline and 2 and 4 weeks later. Pigmentation was effectively treated using QSRL at 2 weeks, but PIH was frequently seen at 4 weeks. There was no significant difference in the incidence of PIH between participants who received oral TA and those who did not. The presence of melasma did not influence the effectiveness of the treatment. Although oral TA has been reported to have depigmentation effects, it may not be effective for preventing PIH after QSRL. Considering the dosage and duration of treatment, an optimal protocol may be needed to induce the efficacy of this treatment to achieve the PIH-preventing effect of oral TA.

In vivo Analysis of Solar Lentigines by Reflectance Confocal Microscopy Before and After Q-switched Ruby Laser Treatment

Solar lentigines are benign lesions usually found on sun-damaged skin. We investigated twelve cases of solar lentigines through dermoscopy and reflectance confocal microscopy, performed before, and 30 min and 10 days after, a single treatment with a Q-switched ruby laser. At baseline, all lesions showed characteristic features of solar lentigines in reflectance confocal microscopy analysis: regular honeycomb patterns, edged dermal papillae and cord-like rete ridges at the dermoepidermal junction. Thirty minutes post-laser treatment, blurred epidermal intercellular connections, dark structureless areas of different sizes and shapes in the lower epidermal layers, and hyporeflective dermal papillae, reflecting epidermal and dermal oedema, were observed. Ten days post-treatment highly reflective round-to polygonal areas and aggregated granules, representing extracellular melanin, were detected in all epidermal layers featuring regular honeycomb patterns. Reflectance confocal microscopy can be used to visualise dynamic skin processes, allowing non-invasive in vivo follow-up of skin lesions after treatment.

Q-Switched Ruby Laser Treatments for Traumatic Tattoos

Q-Switched Ruby Laser Treatments for Traumatic Tattoos

A Case of Congenital, Hairy, Giant Pigmentary Nevus that was Markedly Improved by Q-switched Ruby Laser Treatment

A Case of Congenital, Hairy, Giant Pigmentary Nevus that was Markedly Improved by Q-switched Ruby Laser Treatment

Comparing the effectiveness of Q-switched Ruby laser treatment with that of Q-switched Nd:YAG laser for oculodermal melanosis (Nevus of Ota)

The objective of this study was to compare the efficacy and safety of Q-switched Ruby laser versus Q-switched neodymium:yttrium-aluminium-garnet (Nd:YAG) laser for oculodermal melanosis (Nevus of Ota) birthmarks in a large group of patients. A retrospective review was conducted of 94 patients with Nevus of Ota treated with a Q-switched Ruby laser and a Q-switched Nd:YAG laser over a 3-year period. The subjects' ages ranged from 3 to 64 years; there were 70 females and 24 males, all of whom were of Asian descent. The number of treatments ranged from 1 to 8. Duration of treatment ranged from 6 months to 3 years and 10 months, with a mean of 14 months. Patients (n=47) received Q-switched Ruby laser treatment (694 nm) using light dosages of 7-10 J cm(-2). Subsequent patients (n=47) received Q-switched Nd:YAG laser treatment (1064 nm) using light dosages of 7-10 J cm(-2). The primary efficacy measurement was the quantitative assessment of clearing and fading response using the DermaSpectrometer for the Q-switched Ruby laser group versus the Q-switched Nd:YAG laser group. Based on a paired t-test, clinical and statistically significant differences in clearing and fading response were observed amongst the Q-switched Ruby laser-treated subjects as preferred to the appearance of Q-switched Nd:YAG laser-treated group (P<0.05). In both groups, transient hyperpigmentation resolved in all subjects within 6 months. Permanent hyperpigmentation or scarring was not observed in either group. Use of a Q-switched Ruby laser resulted in better clearing and fading as compared with Q-switched Nd:YAG laser.

Comparison of regional efficacy and complications in the treatment of aberrant Mongolian spots with the Q-switched ruby laser

Background and objective: Aberrant Mongolian spots (AMS) distal from the lumbosacral region are said to be more apt to persist than the typical sacral AMS, so the Q-switched ruby laser (QSRL) has been the treatment of choice for AMS. However, so far as we could determine, there is no statistical analysis of the treatment of AMS. This paper shows statistical comparisons of the efficacy and complications in the treatment of AMS with QSRL. Methods: Fifty-three patients (16 males and 37 females) with 57 AMS regions were treated with the QSRL from March 1999 to April 2007, and we divided the diseased areas into exposed regions that could not be concealed by clothing and non-exposed regions that could be concealed by clothing, and performed a statistical analysis. Results: The results indicated that QSRL treatment of AMS in the exposed regions showed significantly improved coloration and caused less pigmentation when compared with the non-exposed regions. Conclusion: We concluded that QSRL treatment of AMS in the exposed regions is more effective than that of AMS in the non-exposed regions.

Tattooing in the Gulf region: A review of tattoo practices and response to treatment with the Q-switched ruby laser

Background: Data regarding tattoo practices in the Gulf region and response to treatment are almost non-existent in the medical literature. Objective: To study the profile of patients with permanent tattoos in the Arab world, and to evaluate their response to Q-switched ruby laser treatment. Methods: A total of 468 consecutive patients with permanent tattoos consulting us for tattoo removal were recruited in the present study. Before starting the treatment each patient was given a set of questionnaires to answer. The patients were then treated with the Q-switched ruby laser, with a time interval of 8 weeks between each laser session, until complete clearance or up to a maximum of 10 sessions. Results: A total of 292 patients out of 348 patients achieved excellent lightening to complete clearance of tattoo pigment after an average of six sittings (range 2–10 sittings). Female patients with fair complexions and amateur tattoos on the face responded best. Seventy-eight (22.4%) patients developed pigmentary changes. Conclusion: More females than males had tattoos, and at a very young age and mostly on the advice of their parents. The majority of patients wanted to remove the tattoos because of religious reasons. The Q-switched ruby laser seems to be highly effective in removing amateur blue-black tattoos in patients with colored skin.

Adverse effects following Q-switched ruby laser treatment of pigmented lesions

A retrospective study was conducted to investigate the incidence of adverse effects following Q-switched ruby laser treatment of pigmented lesions at the Wessex Specialist Laser Centre. Sixty-one patients received a total of 151 treatments between January 2006 and January 2008. This is the largest series to date of patients on whom adverse effects have been reported following Q-switched ruby laser treatment of an assortment of pigmented lesions. Patients with traumatic or decorative tattoos were excluded from this study. Two of the treatments (1.3%) resulted in adverse effects. One patient developed hyperpigmentation and the other experienced scabbing and subsequent textural change following abrasion of the scab. No predisposing medical or other factors were observed in either patient. This low incidence of adverse effects is consistent with the highly selective absorption of ruby laser light by melanin. The presence of these adverse effects highlights the importance of test patch treatments, the necessity for patients to follow good post-treatment advice and the case for vigilance in monitoring the quality of the laser output.

Early serial Q-switched ruby laser therapy for medium-sized to giant congenital melanocytic naevi

Medium-sized to giant congenital melanocytic naevi (CMN) are difficult to treat, especially if the lesions appear on the face or extremities where treated areas are visible and cosmesis is important. In infants, nests of pigmented naevus reside more superficially and the skin is more transparent than in adults, so we treated medium-sized to giant CMN with early serial Q-switched ruby laser therapy from infancy. We treated nine patients with medium-sized to giant CMN on the face or upper limbs from 1 month of age with early serial Q-switched ruby laser therapy. The laser power was initially 5 J cm(-2) and increased in 0.5 J cm(-2) steps to a maximum of 10 J cm(-2). There were three treatment sites on the forehead, one on the temple, one on the cheek and four on the upper arm. It took 8-15 treatments for the CMN to become a colour similar to the surrounding skin. The mean number of treatments was 9.6. The colour was reduced to 0-20% of the colour of the baseline lesion in all nine patients. Partial slight repigmentation occurred in eight of these patients. These naevi were treated with an additional one or two Q-switched ruby laser irradiations and successfully lightened for at least 1 year. In the remaining patient, pigmentation returned to a level similar to the original lesion within 1 month of the last treatment. Therefore, the lesion was excised for cosmetic reasons. After the treatment series, the skin texture was fine and no patients had hypertrophic scarring. Although treatment of one patient with the Q-switched ruby laser therapy failed, the remaining patients responded well and had good to excellent skin texture without hypertrophic scarring. Early serial Q-switched ruby laser treatment, starting from infancy, is a promising treatment method for this condition.

Combined use of intense pulsed light and Q‐switched ruby laser for complex dyspigmentation among asian patients

Dyspigmentation is a common cosmetic concern among Asians. Many individuals exhibit mixed pigmentary entities including melasma, flat/small seborrheic keratoses, ephelides, solar lentigines and acquired bilateral nevus-of-Ota-like macules (ABNOM). We term this phenomenon complex dyspigmentation (CD) and suggest that a combination strategy may be more efficacious than any singular modality. To determine the effectiveness of combined intense-pulsed light (IPL) for global photorejuvenation along with Q-switched ruby laser (QSRL) for targeted pigment dissolution. Twenty-five Korean women with CD (defined as >2 types of facial pigmentary disorders) were initially treated with IPL followed by repeat treatments every 3-4 weeks as needed. The QSRL treatments, set at low fluence, were added either during the same session or within 1 week of the IPL treatment. Improvement was assessed by the patient, the treating physician and a blinded evaluation of pre- and post-treatment photographs. Using a 4-point scale (1 = poor, 2 = fair, 3 = good, 4 = excellent), 19/25 patients (76%) reporting good-to-excellent response (score "3" or "4"). Two independent physician assessment revealed that 15/25 patients (60%) showed 76-100% improvement while 19/25 patients (76%) showed at least 50% improvement. Side-effects were minimal: 3 patients had transient post-inflammatory hyperpigmentation (12%) and 1 patient (4%) had linear hypopigmentation. Combination treatment with IPL and QSRL is an effective and safe treatment for CD among Asian patients.

Combined Therapy Using Q-Switched Ruby Laser and Bleaching Treatment with Tretinoin and Hydroquinone for Periorbital Skin Hyperpigmentation in Asians

Periorbital skin hyperpigmentation, so-called dark circles, is of major concern for many people. However, only a few reports refer to the morbidity and treatment, and as far as the authors know, there are no reports of the condition in Asians. A total of 18 Japanese patients underwent combined therapy using Q-switched ruby laser to eliminate dermal pigmentation following topical bleaching treatment with tretinoin aqueous gel and hydroquinone ointment performed initially (6 weeks) to reduce epidermal melanin. Both steps were repeated two to four times until physical clearance of the pigmentation was confirmed and patient satisfaction was achieved. Skin biopsy was performed at baseline in each patient and at the end of treatment in three patients, all with informed consent. Clinical and histologic appearances of periorbital hyperpigmentation were evaluated and rated as excellent, good, fair, poor, or default. Seven of 18 patients (38.9 percent) showed excellent clearing after treatment and eight (44.4 percent) were rated good. Only one (5.6 percent) was rated fair and none was rated poor. Postinflammatory hyperpigmentation was observed in only two patients (11.1 percent). Histologic examination showed obvious epidermal hyperpigmentation in 10 specimens. Dermal pigmentation was observed in all specimens but was not considered to be melanocytosis. Remarkable reduction of dermal pigmentation was observed in the biopsy specimens of three patients after treatment. The new treatment protocol combining Q-switched ruby laser and topical bleaching treatment using tretinoin and hydroquinone is considered effective for improvement of periorbital skin hyperpigmentation, with a low incidence of postinflammatory hyperpigmentation.

Gene Expression Profiling of Melanocytes following Q-Switched Ruby Laser Irradiation

Background: The Q-switched Ruby laser (QSRL) is used for the treatment of pigmented lesions. The influence of QSRL treatment on gene expression of nontransformed primary melanocytes has not been addressed in vitro. Objective: We investigated the gene expression profile of melanocytes following QSRL irradiation. Methods: Primary melanocytes were irradiated with the QSRL (694 nm). Early and late transcriptional effects were analyzed using the Affymetrix gene array platform. Results: Laser irradiation of melanocytes had minor effects on mRNA expression. We found only 31 out of 14,500 genes which were at least twofold up- or downregulated. The differential expression of heme oxygenase 1 and galanin in QSRL-treated melanocytes was additionally confirmed by real-time RT-PCR. Analysis of a selection of 36 genes which are known to be associated with malignant melanoma development and progression revealed no significantly aberrant expression in the QSRL-treated melanocytes. Conclusion: Our study shows that QSRL treatment of primary melanocytes in vitro does not cause major alterations of global gene expression and particularly of genes associated with malignant melanoma. However, since QSRL treatment may have different effects on gene expression of melanocytic cells in vivo, further studies are required to evaluate QSRL treatment of (nevo-) melanocytic lesions.

Development of chrysiasis after Q-switched ruby laser treatment of solar lentigines

To the Editor: We describe a woman who developed chrysiasis after Q-switched laser therapy for solar lentigines. There are only two prior reports detailing Q-switched laser-induced chrysiasis.1,2 Our case is an illustrative reminder of this potential side effect of cosmetic laser therapy.

Treatment of Congenital Melanocytic Nevi Using the Combined (Normal-Mode Plus Q-Switched) Ruby Laser in Asians

Clinical response of congenital melanocytic nevus (CMN) to the combined normal-mode ruby laser (NMRL) and Q-switched ruby laser (QSRL) treatment method (ie, NM plus QS) was correlated with the histologic depth of nevomelanocytic nests to predict the efficacy rate and therapeutic outcome of the laser treatment. Thirty-four patients with CMN were treated using the combined (NM plus QS) ruby laser method. The clinical results of the laser treatment demonstrated that 20 had excellent response, 11 had good response, 3 had fair response, and there was no poor response. When correlated with the histologic type, the efficacy rate of the combined ruby laser was significantly higher in the superficial intradermal type than in the others. We conclude that combining the NMRL and QSRL with appropriate parameters to target both superficial and deep nevomelanocytic components provides a greater degree of penetration of laser light.