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The effects of 755 nm alexandrite laser on skin dryness and pruritus

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Advances in Dermatology and Allergology
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Introduction: The alexandrite laser (AL) is a very safe and effective treatment used for unwanted hair removal with a reported success rate of 40% to 80% at 6 months and after several treatment sessions. Although a diffuse variety of side effects has been observed during laser treatment, changes in skin dryness and pruritus before and after AL epilation have not been reported yet to the best of our knowledge. Aim: To investigate the effects of 755 nm alexandrite laser on skin dryness and pruritus at the beginning and in the third and the sixth month after the treatment. Material and methods: Forty three patients with Fitzpatrick skin types of II-IV aged 18-45 with leg hair were included in this prospective study. Patients were treated with 755 nm alexandrite laser with 10-12 mm spot size. According to the skin phototype, the settings of the laser were as follows: 12-22 J/cm² and pulse width of 3 ms. For self-assessment by the patient, the visual analogue scale (VAS) was used before, at the third and sixth month of the treatment as to skin dryness and pruritus. The patients were evaluated by the same dermatologist with the same VAS. The values were compared between before-at the third month, before-at the sixth month and at the third and at the sixth month of the treatment. Results: Pruritus scores were statistically lower at the third month when compared with the baseline scores (p < 0.01). However, there was no difference between the third and sixth month of the treatment as to pruritus scores (p > 0.05). There was a statistically significant difference between the scores before the treatment and the scores at the third month and at the sixth month as to skin dryness (p < 0.001). However, the difference was not prominent between the third and sixth month scores of skin dryness (p > 0.05). Conclusions: To the best of our knowledge, this is the first study researching the effects of AL on pruritus and skin dryness. Further studies with larger samples and longer follow-up periods will be able to better clarify the association.
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Original paper
Address for correspondence: Gunseli Seka Pancar, Department of Dermatology, Samsun Government Hospital, Samsun, Turkey,
e-mail: drgunseliseka@hotmail.com
Received: 14.03.2017, accepted: 1.08.2018.
The eects of 755 nm alexandrite laser on skin dryness
and pruritus
Gunseli Seka Pancar1, Goknur Kalkan2, Oznur Eyupoglu3
1Department of Dermatology, Samsun Government Hospital, Samsun, Turkey
²Department of Dermatology, School of Medicine, Yildirim Beyazit University, Ankara, Turkey
3Department of Statistics, Ondokuz Mayis University, Samsun, Turkey
Adv Dermatol Allergol 2020; XXXVII (1): 29–33
DOI: https://doi.org/10.5114/ada.2020.93381
Abstract
Introduction: The alexandrite laser (AL) is a very safe and eective treatment used for unwanted hair removal with
a reported success rate of 40% to 80% at 6 months and after several treatment sessions. Although a diuse variety
of side eects has been observed during laser treatment, changes in skin dryness and pruritus before and after AL
epilation have not been reported yet to the best of our knowledge.
Aim: To investigate the eects of 755 nm alexandrite laser on skin dryness and pruritus at the beginning and in the
third and the sixth month after the treatment.
Material and methods: Forty three patients with Fitzpatrick skin types of II–IV aged 18–45 with leg hair were
included in this prospective study. Patients were treated with 755 nm alexandrite laser with 10–12 mm spot size.
According to the skin phototype, the settings of the laser were as follows: 12–22 J/cm² and pulse width of 3 ms.
For self-assessment by the patient, the visual analogue scale (VAS) was used before, at the third and sixth month
of the treatment as to skin dryness and pruritus. The patients were evaluated by the same dermatologist with the
same VAS. The values were compared between before-at the third month, before-at the sixth month and at the
third and at the sixth month of the treatment.
Results: Pruritus scores were statistically lower at the third month when compared with the baseline scores
(p < 0.01). However, there was no dierence between the third and sixth month of the treatment as to pruritus
scores (p > 0.05). There was a statistically signicant dierence between the scores before the treatment and the
scores at the third month and at the sixth month as to skin dryness (p < 0.001). However, the dierence was not
prominent between the third and sixth month scores of skin dryness (p > 0.05).
Conclusions: To the best of our knowledge, this is the rst study researching the eects of AL on pruritus and skin
dryness. Further studies with larger samples and longer follow-up periods will be able to better clarify the associa-
tion.
Key words: alexandrite laser, skin dryness, pruritus, hair removal.
Introduction
Laser treatment has recently become a very popular
treatment procedure for the undesirable hair in aesthetic
and cosmetic practice. Several light and laser based pho-
toepilation methods have been used as the treatment
alternatives for unwanted hair removal. The red or near-
infrared wavelengths which are available for photoepila-
tion are about 600 to 1100 nm and include ruby laser
(694 nm), Nd:YAG (neodymium-doped yttrium alumini-
um garnet) laser (1064 nm), diode laser (800–810 nm)
and alexandrite laser (755 nm) [1]. In addition, intense
pulse light (IPL) (590–1200 nm) systems are used for epi-
lation although they are not true laser systems. The aim
of the laser hair removal is the destruction of the fol-
licular unit through thermal injury without damaging the
surrounding skin. Laser hair removal targets melanin (ab-
sorbing chromophore) in the hair bulb and shaft. Ther-
mal injury enlarges and results in the destruction of the
progenitor stem cell [1–3]. The choice of the wavelength
of the laser for hair removal varies among patients based
on the skin type, ethnicity, hair colour and anatomical
site [2]. The alexandrite laser (AL) is commonly used for
hair reduction with a reported success rate of 40% to
80% at 6 months and after several treatment sessions
Advances in Dermatology and Allergology 1, February / 202030
Gunseli Seka Pancar, Goknur Kalkan, Oznur Eyupoglu
[3, 4]. In general, laser hair removal remains a very safe
and eective treatment; however transient or persistent
side eects such as pain, erythema, oedema (10–17%),
hypo-hyperpigmentation (14–25%), blistering, crusting
(10–15%), erosions, purpura, scarring (0–5%) and follicu-
litis may be observed [5].
Besides, paradoxical hypertrichosis, superficial
thrombophlebitis, hyperhidrosis, bromhidrosis, and leu-
cotrichia have also been reported [6–9]. Although a dif-
fuse variety of side eects has been observed, changes
in skin dryness and pruritus before and after AL epilation
have not been reported yet to the best of our knowledge.
Aim
Therefore, in this study, we aimed to investigate the
eects of 755 nm AL (that is used for leg hair removal) on
skin dryness and pruritus before, at the end of 3-month
and 6-month follow-up.
Material and methods
Patient selection
Forty three patients with Fitzpatrick skin types of II–IV
aged 18–45 with leg hair were included in this prospec-
tive study. All of participants signed the informed con-
sent before starting any intervention. Exclusion criteria
consisted of current and planned pregnancy, lactation,
menopause patients with chronic systemic disease,
patients receiving systemic medications, previous laser
treatment for leg hair, dermatological disease located on
legs, patients who have keloid history, infection at the
treated area and tanned skin. Patients were treated with
755 nm AL (Light Age Inc, Epicare-LPXTM, USA) with 10–
12 mm spot size. According to the skin phototype, the
settings of the laser were as follows: 12–22 J cm² and
pulse width of 3 ms (repetition rate of 5 Hz). Cooling De-
vice (Zimmer Cryo 6, Cold Air Device, USA) was used dur-
ing the laser procedure. Patients were all evaluated by
a dermatologist.
Treatments were given monthly. Fluency was in-
creased if there were no side eects following the previ-
ous session. Pulse width remained constant.
For self-assessment by the patient, the visual ana-
logue scale (VAS) was used before, at the third and sixth
month of the treatment as to skin dryness and pruritus.
The patients were evaluated by the same dermatologist
with the same VAS. The patients were asked to quantify
the presence of skin dryness and pruritus using VAS at
10 points (0 – no dryness, no pruritus and 10 – most se-
vere dryness and pruritus). The physician also evaluated
dryness only with the same VAS. The values were com-
pared between before – at the third month, before – at
the sixth month and at the third and at the sixth month
of the treatment.
Statistical analysis
Statistical analysis was performed using SPSS 15.0
(SPSS, Inc, Chicago, IL, USA). Paired-samples t test and
Wilcoxon signed-rank test were used to determine
changes between baseline measures and those at the
third and at the sixth month of the treatment. The asso-
ciation between parameters was assessed by Pearson’s
correlation test. The level of statistical signicance was
set at p < 0.05.
Results
Forty-three patients (women) were enrolled in our
prospective analysis. The mean age was 32.34 ±87. The
patients had mostly type II–III and IV of Fitzpatrick’s skin
phenotype.
Pruritus score was 1.88 ±2.48 before treatment and it
was 0.005 ±0.30 at the third month. Pruritus scores were
statistically lower at the third month when compared
with the baseline scores (p < 0.01). However, there was
no dierence between the third and sixth month of the
treatment as to pruritus scores (p > 0.05). Skin dryness
was 0.67 ±1.08 before treatment and 2.35 ±2.21 at the
third month and 2.33 ±2.25 at the sixth month. There was
a statistically signicant dierence between the scores
before the treatment and the scores at the third month
and at the sixth month (p < 0.001). However, the dier-
ence was not prominent between third and sixth month
scores of skin dryness (p > 0.05).
Also, the physician assessment revealed that skin
dryness was signicant at the third and sixth months of
the laser treatment when compared with the baseline
scores (p = 0.001). The maximum score of 7 was given in
all of the groups. The results were summarized in Table 1.
Discussion
In this study, we investigated the eect of laser hair
removal on skin dryness and pruritus to determine
whether skin dryness is a newly reported adverse eect
or not during laser treatment and to detect if AL can be
used as a treatment model for the pruritus on legs. The
assessments were done at the beginning, at the third
and sixth month after the treatment. Pruritus scores at
the third month were found as statistically lower than the
scores at the beginning. A statistically signicant dier-
ence was also detected between the skin dryness scores
before the treatment and the scores at the third month
and at the sixth month of the treatment (p < 0.001).
To the best of our knowledge, this is the rst study
researching the eects of AL on pruritus and skin dry-
ness. We would like to attract attention to these rarely
seen eects of a very common technique that is used in
daily practice routinely and to alert our colleagues about
this issue.
Advances in Dermatology and Allergology 1, February / 2020
The eects of 755 nm alexandrite laser on skin dryness and pruritus
31
Alexandrite laser was revealed as the most effec-
tive and painless photoepilation method according to
the most of the results of the reported studies in the
literature [5, 9]. Hyperpigmentation, hypopigmenta-
tion, erythema, crusting and oedema are transient and
sometimes persistent common side eects of these la-
ser systems [5, 6]. Other uncommon side eects include
induction or aggravation of acne, rosacea-like rash, pre-
mature greying of hair, tunnelling of hair under the skin,
prolonged diuse redness and oedema of the face, and
severe persistent urticaria [5–9]. In our study, skin dry-
ness is newly diagnosed uncommon adverse eect. The
mechanism leading to dryness cannot be exactly under-
stood. However, the mechanisms proposed may be direct
thermal injury of the skin or indirect stimulation by nerve
bres, laser penetration and parameters, skin type, body
localization, seasonal changes, genetic factors and sun
exposure. Thermal injury leading to destruction of the
pilosebaceous unit and eccrine gland with secondary in-
ammation may be the other factor in the explanation
of the skin dryness after laser treatment.
The pilosebaceous unit (PSU) and eccrine sweat
gland (ESG) are classically described as completely in-
dependent skin appendages. The secretory segment of
the ESG approximates the hair follicle in a position below
the sebaceous gland. They are the major implications in
supporting the humidity of the skin [10]. The best known
diseases of the PSU and ESG are acne vulgaris, hidrad-
enitis suppurativa, rhinophyma and syringocystadenoma
papilliferum. Diode laser, pulsed dye laser and IPL were
used to improve these diseases [10, 11]. However, the ef-
fect of AL on PSU and is not fully known.
The outgrowth of cells from ESGs is the major fea-
ture of repair in the skin. Reduced outgrowths of ESG,
reduced cell-cell cohesiveness and reduced number of
desmosomes delay wound closure, lead to a thinner
epidermis and dry skin. Rittie et al. investigated the im-
paired wound closure and dryness in the elderly skin.
They suggested that reduced cell cohesiveness of out-
growths from eccrine sweat glands delays wound clo-
sure and leads to the dryness of the skin compared with
young adults [12]. We suppose that the eect of AL on
skin dryness may be with the same mechanism as act-
ing in the elderly skin. From this point of view, the histo-
pathological examinations, immunohistochemical and
electron microscopic studies should be done to rule out
the dryness process before and after laser application
on the skin.
Selective photothermolysis of melanin in hair follicles
is the main principle for laser assisted hair depilation.
However, the melanin in the epidermis must be pro-
tected. Dynamic cooling devices (DCD) are used for this
purpose. These devices use tetrauoroethane and have
a boiling point of –26.2°C. The liquid cryogen drop sets
undergo evaporation and cool epidermal temperature
[13, 14]. We also used this kind of devices to protect epi-
dermis in this study. We suggest that the uctuations of
the epidermal temperature may be the reason for the
skin dryness that was reported in our study. Further stud-
ies comparing skin dryness in two groups composed of
AL treatment with or without cooling systems are needed
to support and clear this suggestion. Nahm et al. reported
that cryogen usage during laser hair removal minimizes
the pain and protects the skin [13]. In fact, the patients
selected for epilation in this study consisted of mostly
lighter skin phototypes. As we know, higher fluencies
are used on lighter skin phototypes. As a result of the
changes in laser settings, the thermal energy delivering
to epidermis is more signicant than darker ones. Our
patient selection was also composed of lighter skin pho-
totypes, therefore the studies together with darker skin
phototypes should be organized for clarifying the eects
of AL on skin dryness in all types of phototypes.
Alavi et al. evaluated the effects of AL on skin pa-
rameters such as melanin content, skin layer depth, elas-
ticity, density and transepidermal water loss (TEWL) by
biometric methods [15]. They revealed that four sessions
(with 4-week intervals) of AL could decrease melanin
content of the skin and make the skin thinner, however
it could increase elasticity and density of epidermis and
dermis by decreasing TEWL. Decreased TEWL signied
the improved skin ability to retain its water and keep
the skin barrier intact [16]. As the decrease in epidermis
depth was especially caused by the decrease in stratum
corneum, we suggest that in our study the skin dryness
may be the result of the decreased layer of the epider-
mis, however to be able to have an assertive conclusion,
we should perform a biopsy and examine the epidermis
histopathologically during laser treatment. Unfortunate-
ly, we were unable to make pathological examination
in our study. Besides there are also more objective and
quantitative physical measurement systems such as ca-
pacitance measurement, infrared-spectroscopy, electrical
resistance measurement, resonance frequency measure-
ment, profilometry and scanning electron microscopy
for determining the dryness of the skin. Further studies
Table 1. The mean and median VAS scores
Variable Pruritus, mean ± SD Skin dryness, mean ± SD Observer, mean ± SD
Before the treatment 1.88 ±2.48 0.67 ±1.08 0.91 ±1.17
Third month 0.05 ±0.30 2.35 ±2.21 2.63 ±2.16
Sixth month 0.03 ±0.30 2.33 ±2.25 2.67 ±2.14
Advances in Dermatology and Allergology 1, February / 202032
Gunseli Seka Pancar, Goknur Kalkan, Oznur Eyupoglu
evaluating skin dryness with these methods will be much
better to clarify the eect of laser treatment on the skin.
In addition, the skin dryness and pruritus should be
evaluated and compared with other lasers that are used
for hair removal. The patients in our study had no other
side eects of laser treatment.
Current knowledge shows that dry skin is usually re-
lated with higher pruritus rates. However, our ndings
contradicted these data as skin dryness increased while
pruritus was decreasing. Therefore, we can infere that
something acts dierently in the laser irradiated skin.
These eects should be investigated to see if they are
transient or persistent, therefore a long follow-up period
will better illuminate these newly observed skin reac-
tions.
The expressions of inammatory cytokines with laser
irradiation have been reported in various studies. Shiba
et al. studied the Neodymium-daped yttrium-aluminium-
garnet laser (Nd:YAG) on IL-6 levels with the activated
protein kinase pathway resulting in the anti-inamma-
tory eect. Shiba et al. reported that the Neodymium-
daped yttrium-aluminium-garnet laser (Nd:YAG) irradia-
tion resulted in inhibition of the increase in IL-6 levels
through the activated protein kinase pathway resulting
in an anti-inammatory eect [17].
Dang et al. revealed that 532-nm laser and 1064-nm
laser accelerated collagen synthesis due to upregulation
of transforming growth factor β (TGF-β), Hsp 70 and IL-6
levels. TGF-β was also found to be up-regulated with
800-nm diode laser in another study. As a result of these
studies, we can conclude that laser irradiation inuences
the inammatory responses of the aected skin [18, 19].
Fractional CO2 and pulse dye laser were also reported
as useful laser techniques used to improve intense pru-
ritus in hypertrophic burn scars, which is an undesirable
consequence of these methods [20]. The eect of AL on
pruritus has not been reported in the literature until now.
In our study, pruritus scores were signicantly decreased
compared to the baseline scores before the treatment of
AL. Our ndings suggest that the anti-inammatory ef-
fects of lasers and the dierent distribution pattern of cy-
tokines after laser irradiation may be the sources of the
decreasing pruritus scores. In the light of these studies,
AL can be a promising treatment method for the patients
who are concerned about pruritus located on legs. How-
ever, additional studies are required in dierent sections
of the body by using immunohistochemical methods
concomitantly evaluating the patients with VAS to be
able to measure local cytokine distribution of the aect-
ed skin and observe the changing prole of inammatory
reaction to the laser therapy. Son et al. suggest that dry
skin is due to decreased bleomycin hydrolase expression
and reduction in laggrin degradation. Maintenance of
water balance in the stratum corneum is determined by
these factors and intercellular lipids in corneocytes [21].
Filaggrin degradation and intercellular lipid destruction
after the application of AL may be a causative factor of
skin dryness. However detailed studies are needed.
Consequently, laser treatment for hair removal oers
a comfortable and pleasing service that increases quality
of life. However, reported newly adverse eects have been
increasing with each passing day. Therefore, clinicians
should be alert and aware about these current skin reac-
tions of this common procedure and inform the patients.
Besides, contributions to the improvement of pru-
ritus are promising positive effects of AL on pruritus.
Further investigations with larger samples and longer
follow-up periods are required to be able to clear the ac-
curate mechanisms causing these skin changes and this
approach will be able to provide the eective usage of
these devices.
Conict of interest
The authors declare no conict of interest.
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... The use of LILT for the treatment of musculo-skeletal disorders, soft tissue injuries, and wound healing, all of which can be colonized by bacteria, has been found to be effective. ( propagate and enter tissues (Pancar et al., 2020). When bacteria are exposed to the Alexandrite laser, their temperature rises. ...
Thesis
Full-text available
Background: Laser is a novel physical therapy technique used to treat a variety of conditions, including wound healing, inhibition of bacterial growth, and postoperative wounds. High-Power pulsed alexandrite laser therapy is one of the most prevalent forms of laser therapy, which is a noninvasive method for treating a variety of pathological conditions, thereby enhancing functional capacities and quality of life. It is a modern medical and physiotherapeutic technology. Generally, the Alexandrite laser emits infrared light with a wavelength of 755 nm, allowing it to propagate and penetrate tissues. Objective: The study focused on the application of a high-power pulsed alexandrite laser in vitro to evaluation the effect of a pulsed alexandrite laser on antibiotic-resistant bacteria utilizing varying exposure times, pulse durations, and laser fluencies to determine which dose is more effective on Staphylococcus aureus bacteria. Method: The laser system was fixed vertically on mechanical jack supported with height tuner screw on plane bench; so the laser beam can fall vertically on the test sample and the laser aperture was stick to the test sample. The alexandrite laser that was used in the study which was considered as pulsed laser and had the following parameters: The wavelength was 755 nm, the beam diameter was (14 mm), the exposure times varied (30, 60, 90) seconds, the laser fluency (5, 10, 15 and 20 J.cm⁻²) and pulsed duration (5 , 10 , 20 ms ). The study was carried out after the bacteria were diagnosed as being resistant to antibiotics, they were exposed to different doses of Alexandrite laser. Three isolates of bacteria were exposed to laser beams for 30 seconds with a 5ms of pulse duration and with a laser fluency of 5J/cm2 and the process were repeated with laser fluencies of 10, 15, and 20. The procedure was repeated using exposure times of 60sec and 90sec. As well as, the process was repeated by expose with 30 sec, 60 sec and 90 sec exposure times, 10ms pulse duration and with laser fluencies 5, 10, 15 and 20J/cm², II separately. Also, the previous process was repeated by expose the bacteria with different exposure times (30 sec, 60 sec and 90 sec), 20ms pulse duration and with different laser fluencies (5, 10, 15 and 20J/cm²), separately. Results: At 30, 60 and 90 sec exposure times, there are significant reduction (p = <0.0001) in mean of the bacteria colonies was observed with the increase of laser fluency doses at the same pulse duration. As well as, a significant reduction (p = <0.0001) in mean of the bacteria colonies was observed with in comparison between two laser fluencies at the same pulse duration. However, there are no significant differences in mean values of colony count between control and 5 J.cm⁻² at 20ms pulse duration. At 5ms and 10ms pulse durations, there are
... Based on anecdotal reports in humans, the potential utility of various complementary treatment modalities remains to be elucidated more clearly in the future, e.g. regarding the 755 nm alexandrite laser, botulinum toxin, acupuncture, transcranial magnetic stimulation, extracorporeal shockwave therapy, massage with violet oil, positive verbal suggestions or music therapy [223][224][225][226][227][228][229][230][231]. ...
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Background: Laser is a novel physical therapy technique used to treat various conditions, including wound healing, inhibition of bacterial growth, and postoperative wounds. High-power pulsed alexandrite laser therapy is one of the most prevalent forms of laser therapy, which is a noninvasive method for treating various pathological conditions, thereby enhancing functional capacities and quality of life. It is a modern medical and physiotherapeutic technology. Generally, the Alexandrite laser emits infrared light with a wavelength of 755 nm, allowing it to propagate and penetrate tissues. Objective: This study focused on the application of a high-power pulsed alexandrite laser in vitro to evaluate the effect of a pulsed alexandrite laser on antibiotic-resistant bacteria utilizing varying exposure times, pulse durations, and laser fluencies to determine which dose is more effective on S. aureus bacteria. Method: The laser used in this study was the alexandrite laser which was considered a pulsed laser and had the following parameters: The wavelength was 755 nm, the beam diameter was (14 mm), the exposure times varied (30, 60, 90) seconds, the laser fluency (5, 10, 15 and 20 J.Cm-2). The study was carried out after the bacteria were diagnosed as being antibioticresistant. They were exposed to different doses of Alexandrite laser. Three samples of bacteria were exposed to laser beams for 30 seconds with a 5ms pulse duration and with a laser fluency of 5J/cm2, and this process was repeated with laser fluencies of 10, 15, and 20. This procedure was repeated using exposure times of 60sec and 90sec. As well as, this process was repeated by exposure with 30 sec, 60 sec and 90 sec exposure times, 10ms and 20ms pulse durations and with different laser fluencies 5, 10, 15 and 20J/cm2, separately. Results: A significant reduction (p = <0.0001) in the mean values of the colony was observed with the increase of laser fluency doses compared with control at the same pulse duration. A significant reduction (p = <0.0001) in the mean count of the colonies was observed in the comparison between two laser fluences at the same pulse duration. In conclusion, the exposure times, pulse durations and laser fluencies of pulsed alexandrite laser showed an effect on the mean count of the colonies of S aureus bacteria and determined the effective dose. Keywords: laser, Staphylococcus aureus, Bacteria growth
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Laser treatment is a widespread method for hair removal. Despite its very common use, side effects remain relatively rare and transient. Axillary hyperhidrosis and bromhidrosis have already been reported in the literature after depilatory lasers. We report here a novel side effect of total body bromhidrosis following hair removal laser. A 27-year-old man, phototype 3 underwent four sessions of total body depilatory laser, combining pulsed alexandrite and pulsed diode lasers. A few days afterwards, a generalized foul odor was noted and was resistant to regular deodorants and Aluminum chloride based antiperspirants. Possible mechanisms include the activation of dormant bacteria in the skin flora, sweat gland dysfunction, altered skin flora, sweat gland hormone receptor disturbances, and genetic factors. Total body bromhidrosis and hyperhidrosis are potential complications of total body laser hair removal.
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Lasers and intense pulsed light (IPL) are now used worldwide for prolonged photo-epilation. To study the side effects of IPL hair removal therapy among 2541 female hirsute patients as the largest series reported so far in the literature. The first series of 1000 patients were treated by the Lumina IPL system. (Lynton Lasers, UK). The second series of 1541 patients were treated by Vasculight-SR, a multi-functional laser and IPL system (Lumenis, Inc., USA). The fluences used for Lumina varied between 16 and 30 J/cm2. The parameters used for Vasculight-SR were as follows: fluences ranged from 33 to 42 J/cm2; pulse duration was 3-5 ms, and pulse delay was 20-80 ms. The pulse mode was either double or triple. The parameters were chosen according to the patients' Fitzpatrick skin types and tolerance. The cut-off filters frequently used were 695, 755, 645 and 615 nm in descending order of their frequencies. Patients were treated every 4-6 weeks and for eight sessions or more. All patients were followed for up to 20 months. Series 1 - burning and its sequelae presented as post-inflammatory hyperpigmentation (PIH), post-inflammatory hypopigmentation (PIHPO), bulla and erosion, and finally scar formation in 75, 10, 64 and one case, respectively. Leukotrichia, folliculitis, and paradoxical hypertrichosis were recorded in 40, 35, and 12 more cases, respectively. Series 2 - PIH and PIHPO were recorded in 28 and four patients. Erosion and crust formation were recorded in 28 patients. Paradoxical effect, leukotrichia and acne formation were seen in 79, 27 and 19 cases, respectively. Burning and its sequellae, leukotrichia, paradoxical hypertrichosis and folliculitis are four major side effects of IPL hair removal therapy in our study.
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The extended theory of selective photothermolysis enables the laser surgeon to target and destroy hair follicles, thereby leading to hair removal. Today, laser hair removal (LHR) is the most commonly requested cosmetic procedure in the world and is routinely performed by dermatologists, other physicians, and non-physician personnel with variable efficacy. The ideal candidate for LHR is fair skinned with dark terminal hair; however, LHR can today be successfully performed in all skin types. Knowledge of hair follicle anatomy and physiology, proper patient selection and preoperative preparation, principles of laser safety, familiarity with the various laser/light devices, and a thorough understanding of laser-tissue interactions are vital to optimizing treatment efficacy while minimizing complications and side effects.
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Cultured human skin fibroblasts were irradiated twice successively with the 1.5 J/cm(2) of 532-nm and 1,064-nm lasers, respectively. The mRNA of procollagen, matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), heat-shock protein 70 (Hsp70), interleukin-6 (IL-6) and transforming growth factor beta (TGF-beta) were analyzed at 24 and 48 h post-irradiation by using RT-PCR. Both lasers significantly increased the expression of type I and III procollagen, TIMP1, and TIMP2, but decreased MMP1 and MMP2 expression. The 1,064-nm laser initiated TGF-beta expression while the 532-nm laser elicited the increase of Hsp70 and IL-6. The increase/decrease rates of procollagen, TIMPs and MMPs for the 1,064-nm laser were higher than that of the 532-nm laser. Thus, both lasers effectively accelerated collagen synthesis and inhibited collagen degradation. Collagen synthesis induced by the 1,064-nm laser might be partly due to the upregulation of TGF-beta expression, while the increase of Hsp70 and IL-6 might be partly responsible for collagen synthesis stimulated by the 532-nm laser. With the parameters used in this study, the 1,064-nm infrared laser is more effective in promoting the beneficial molecular activities than the 532-nm visible laser.