Superior lipolytic effect of the 1,444 nm Nd:YAG laser: Comparison with the 1,064 nm Nd:YAG laser

Efficacy of 1060 nm Diode Laser for Non-Invasive Subcutaneous Fat Reduction in Mini-Pigs

Purpose

To evaluate the efficacy and safety of abdominal fat reduction in mini-pigs, utilizing at 1060 nm diode laser with a wavelength of 1060 nm.

Patients and Methods

The laser system non-invasively disrupts adipose tissue; its effectiveness and safety were evaluated by ultrasound imaging and histological analysis. Laser irradiation was performed with various powers, and the cooling function was activated to prevent skin surface damage.

Results

The dermal tissue temperature increased to at least 43°C during laser exposure, leading to a decrease in abdominal fat thickness after 30 days. Blood tests revealed no significant changes in kidney and liver function but showed increased blood levels of nonessential free acids (NEFAs), likely due to the release of fatty tissue-derived free fatty acids. Histological evaluation demonstrated rapid transformation of adipose tissue into collagen, muscle fibers, and intracellular fibrous tissue.

Conclusion

The 1060 nm laser showed promise as a non-invasive and safe tool for reducing abdominal fat.

Novel Management of Granuloma Formation Secondary to Dermal Filler with Intralesional 1444 nm Nd:YAG Laser Technique

Background: Dermal fillers for soft tissue for the treatment of face sagging, volume loss, and wrinkles have become popular among patients of all ages and ethnicities, and their use is becoming increasingly widespread. Aim: the goal of this study was to evaluate the effectiveness and safety of a micro-pulsed, 1444 nm Nd:YAG laser on dermal filler complications, in particular on granuloma management. Methods: A subcutaneous, 1444 nm Nd:YAG laser was used on five female patients (range age 52-68 years) with hyaluronic filler granulomas located on the face (two on the cheek area and three on the lips); three patients had self-injected the filler, buying it online. Before and after the therapy, the patients received a skin ultrasound to determine the form and location of the granulomas and to determine if there had been a full or partial resolution. During this study, all possible adverse effects at the treatment site were monitored. The 5-point Global Aesthetic Improvement Scale (GAIS) (0 point-no change; 1 point-25%, mild improvement; 2 points-50%, moderate improvement; 3 points-75%, good improvement; 4 points-100%, excellent improvement) was recorded at a 3-month follow-up. Results: good results were obtained in the treatment of filler granulomas with the intralesional 1444 nm laser, even if just a single treatment was performed (one intervention was effective for curing granulomas up to 5 mm in diameter). Three patients were satisfied with excellent improvement, and two patients experienced good improvement. The results are functional and aesthetically satisfying, as shown by photographic assessment. At the last follow-up, the granuloma had reduced or completely disappeared in all cases, and no infections, burns, scarring or fibrosis, episodes of severe bleeding, or other serious adverse effects had been reported. All subjects tolerated the post-treatment period well. Conclusions: Our findings showed that granuloma treatment with an intralesional 1444 nm Nd:YAG laser is a minimally invasive, easy, fast, efficient, and low-risk procedure.

Facial and body contouring with 1444 nm Nd:YAG laser-assisted lipolysis: Clinical evidence

BACKGROUND

Body contouring is a significant area of dermatologic and plastic surgery. Surgical procedures, like surgical lipectomy, and less invasive procedures, such as various liposuction techniques, are the two main ways to reduce fat.

AIM

Our study showed that 1444 nm Nd:YAG laser-assisted lipolysis used with appropriate and specific parameters effectively destroys adipose tissue avoiding these risks and determining a safe clinical application.

METHOD

A subcutaneous, 1444 nm Nd:YAG laser was used on 132 patients (range, 18-73 years; 109 women and 23 men with Fitzpatrick skin phototypes ranging between II and V) requiring body and face contouring. All patients were photographed for documentation. Digital clinical photography was taken under as near identical conditions as possible at baseline (pre-treatment), and 16 weeks post-treatment. The 5-point Global Aesthetic Improvement Scale (GAIS) was recorded immediately after treatment and at their final assessment session (4 months). Adverse events were monitored.

RESULTS

On the basis of the investigator-evaluated GAIS scale, the total GAIS scores showed satisfactory results. Clinician assessment from the clinical photography showed good efficacy and visible aesthetic results for body and face areas. No serious or unexpected adverse side effects were recorded, and transient pain, oedema, erythema and slight induration resolved within the first week of treatment.

CONCLUSIONS

The 1444 nm Nd:YAG laser is a new tool for performing lipolysis, and this study reports its effectiveness and safety.

Minimally invasive 1,444-nm Nd:YAG laser treatment for axillary bromhidrosis

Background

Axillary bromhidrosis is an apocrine glands hyperactivity disease.

Methods

A total of 24 patients (15 men and 9 women) with axillary bromhidrosis underwent a laser procedure with a 1,444-nm Nd:YAG laser. Parameters evaluated in this study were as follows: the degree of malodor (T0, baseline; T30, after 1 month; and T180, after 6 months), postoperative pain, short-term decreased mobility (T1, after 1 day; T7, after 7 days; and T30, after 1 month), and overall satisfaction (T30, after 1 month and T180, after 6 months). A visual analog scale (VAS), from 0 to 10, was used to assess pain and decreased mobility, with lower values denoting less severity.

Results

A total of 24 patients were followed up for 6 months after laser treatment. At baseline, all patients (100%) complained of a strong axillary malodor (mean degree of malodor at T0 = 2.0 ± 0.00). It decreased to 0.50 ± 0.64 at T30. At T180, the degree of malodor was 0.54 ± 0.57. Both T30 and T180 degrees of malodor significantly decreased from the baseline value (p < 0.01). The mean degree of patient satisfaction at T30 was 1.75 ± 0.52, and at T180, it was 1.67 ± 0.21. Among the 24 patients, eight complained of moderated pain 1 day after treatment. The pain subsided on day 7, except for two patients, with VAS = 1. Pain and mobility restrictions were in any case resolved within T30.

Conclusion

Treatment with a 1,444-nm Nd:YAG laser for subdermal interstitial coagulation could be a less invasive and more effective option treatment for axillary bromhidrosis.

Lipoma management with a minimally invasive 1,444 nm Nd:YAG laser technique

BACKGROUND

Lipoma is the most common benign mesenchymal tumor that is composed of mature fat cells. Subdermal laser lipoma treatment may be recommended as an alternative to surgery for its removal.

PURPOSE

The purpose of the study was to investigate the efficacy of the 1,444 nm Nd:YAG laser subcutaneous intralesional application as a treatment option for lipoma.

MATERIALS AND METHODS

On 60 patients (37 women and 23 men) with lipomas localized above the muscle and lipomatosis in various regions, a subcutaneous, micro-pulsed 1,444 nm Nd:YAG laser procedure was executed. Before treatment, an ultrasound was performed and the lipomas were measured. The same lighting setup and photographic tools were used to take pictures of each patient.

RESULTS

The lipoma reduced or completely disappeared in all cases at the last follow-up, and no infections, burns, skin lesions, episodes of severe bleeding, or other serious adverse effects were reported. The most common transient side effects were ecchymosis and edema. Partial lesion reduction refers to rare cases of lipomatosis in which the lipomas were so small that suction and accurate positioning of the capsular membrane contours were impossible.

CONCLUSION

Lipoma treatment with a 1,444 nm Nd:YAG laser is a safe and effective minimally invasive procedure without risk of scarring. For cellular disruption, laser treatment is an effective and safe option.

Efficacy and safety of 1440-nm Nd:YAG laser on lower face and neck rejuvenation

Reviewing the literatures, we did not found-to our knowledge-any study using the Nd:YAG laser with wavelength 1440 nm in assisted liposuction and rejuvenation of the head and neck region although of the higher absorption rate for fat and water. Evidence-based practice supports the benefits of laser-assisted liposuction over conventional liposuction with skin tightening in selected areas specifically the submental area and the neck. The aim of the work is to evaluate the efficacy and safety of Nd:YAG laser wavelength (WL) 1440 nm on lipolysis of submental area and skin tightening of the lower face and neck area. Fifty-seven patients with submental localized fat deposits and mild to moderate skin laxity were subjected to laser liposuction using Nd:YAG laser with WL 1440 nm (SmartLipo Triplex)® device. The efficacy of skin laxity improvement was assessed together with the whole satisfaction rate for each patient. Overall satisfaction rate was 97% of the patients. One sample test regarding skin laxity showed significant improvement (34.6%) after 6 months follow-up (0.268 SD p < 0.05) (Table 4). Complications included edema, soreness, weakness in the lower lip, and ecchymosis that resolved conservatively except one case that complained of seroma which needed aspiration and healed without infection. In conclusions, Nd:YAG laser with WL 1440 nm can be used safely and effectively for submental-assisted liposuction and lower face and neck rejuvenation. Less laser energy was needed for lipolysis and skin tightening as the fat and water have a higher absorption rate at wavelength 1440 nm.

Multi-modal treatment strategy for achieving an aesthetic lower face

BACKGROUND

Most women consider an oval-shaped face to be youthful and beautiful. In recent years, demand has grown for surgical procedures with a shorter downtime and fewer complications. These minimally invasive procedures include botulinum toxin type A (BoNTA) injection, filler injection, suction-assisted liposuction (SAL), laser-assisted lipolysis (LAL), thread lifting, and fat grafting. This study aims to introduce an effective method for creating an aesthetically pleasing lower face using a combination of minimally invasive procedures.

METHODS

From March 2017 to March 2019, 94 patients simultaneously underwent LAL, SAL, and thread lifting. Ancillary procedures such as BoNTA injections, hyaluronic acid filler injections, and removal of the buccal fat pad (BFP) were selectively performed according to the patient's condition.

RESULTS

Patients rated their postoperative satisfaction as very satisfied, satisfied, dissatisfied, or very dissatisfied. Approximately 83% of all respondents were satisfied with the results, whereas the remaining respondents had complaints regarding the outcomes. The most common reasons for dissatisfaction were a longer-than-expected recovery time and undercorrection, and the most severe complaint was skin depression as a result of overcorrection.

CONCLUSIONS

Our method of simultaneously performing LAL, SAL, and thread lifting, while adding BoNTA, filler injections, and BFP removal as needed, was capable of producing consistent and reliable aesthetic outcomes for the lower face.

Clinical efficacy of 1,444nm Nd:YAG laser for xanthelasma palpebrarum

Xanthelasma palpebrarum (XP) does not regress spontaneously and most patients complain of cosmetic discomfort. This study presents the results of treatment of XP using 1,444 nm Nd:YAG laser. We aim to evaluate the clinical efficacy of a 1,444 nm Nd:YAG laser in XP. Twenty-eight patients with XP treated with 1,444 nm Nd:YAG laser were analyzed retrospectively. A physician scored the results based on the reduction of the initial lesion area under six categories. The results were scored as follows: no effect (0% clearing of xanthelasma area), some response (1-24% clearing), moderate response (25-49% clearing), marked response (50-74% clearing), satisfactory result (75-99% clearing), and excellent result (100% clearing). Twelve patients (42.8%) showed excellent clearance and 10 patients (35.7%) had clearance greater than 75%. Overall, 24 patients (85.7%) showed improvement higher than 50%. Half of the patients (14 patients) ended the treatment with satisfactory results with one treatment session. Including seven patients who ended the treatment after two laser sessions, 21 patients (75%) reported satisfactory results and ended the treatment after 1 to 2 laser sessions. XP treatment with 1,444 nm Nd:YAG laser showed promising results. We believe it can be an effective and safe treatment modality for XP.

Terminal Deoxynucleotidyl Transferase-Mediated Deoxyuridine Triphosphate Nick End Labeling (TUNEL) Assay to Characterize Histopathologic Changes Following Thermal Injury

Background

Despite the wide application of lasers and radiofrequency (RF) surgery in dermatology, it is difficult to find studies showing the extent of damage dependent on cell death.

Objective

We evaluated histopathologic changes following in vivo thermal damage generated by CO₂ laser, 1,444 nm long-pulsed neodymium:yttrium-aluminum-garnet (LP Nd:YAG) laser and RF emitting electrosurgical unit.

Methods

Thermal damage was induced by the above instruments on ventral skin of rat. Specimens were stained with hematoxylin and eosin, along with a terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) assay, to highlight the degree of irreversible cellular injury.

Results

The volume of vaporization was largest with the CO₂ laser. Area of cell death area identified by TUNEL assay, when arranged from widest to narrowest, was 1,444 nm LP Nd:YAG laser, CO₂ laser, and RF emitting electrosurgical unit.

Conclusion

This histopathologic evaluation of the acute characterization of injury across devices may be advantageous for attaining better treatment outcomes.

High Power 1443.5 nm Laser with Nd:YAG Single Crystal Fiber

A high-power eye-safe 1443.5 nm laser was demonstrated with an Nd:YAG single crystal fiber (SCF) as the gain medium. For continuous wave (CW) operation, a maximum output power of 13.3 W was obtained under an absorbed pump power of 95.0 W, corresponding to an optical-to-optical conversion efficiency of 14.0%. For acousto-optically (AO) Q-switched regime, an output power of 1.95 W was obtained at a pulse repetition frequency (PRF) of 10 kHz. The pulse duration was 69.5 ns. The pulse energy and peak power were calculated to be 195 µJ and 2.81 kW, respectively.

Evidence-Based Medicine: Liposuction

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Review the appropriate indications and techniques for suction-assisted lipectomy body contouring surgery. 2. Accurately calculate the patient limits of lidocaine for safe dosing during the tumescent infiltration phase of liposuction. 3. Determine preoperatively possible "red flags" or symptoms and signs in the patient history and physical examination that may indicate a heightened risk profile for a liposuction procedure. 4. Provide an introduction to adjunctive techniques to liposuction such as energy-assisted liposuction and to determine whether or not the reader may decide to add them to his or her practice.

SUMMARY

With increased focus on one's aesthetic appearance, liposuction has become the most popular cosmetic procedure in the world since its introduction in the 1980s. As it has become more refined with experience, safety, patient selection, preoperative assessment, fluid management, proper technique, and overall care of the patient have been emphasized and improved. For the present article, a systematic review of the relevant literature regarding patient workup, tumescent fluid techniques, medication overview, and operative technique was conducted with a practical approach that the reader will possibly find clinically applicable. Recent trends regarding energy-assisted liposuction and body contouring local anesthesia use are addressed. Deep venous thromboembolism prophylaxis is mentioned, as are other common and less common possible complications. The article provides a literature-supported overview on liposuction techniques with an emphasis on preoperative assessment, medicines used, operative technique, and outcomes.

Assessment of equivalence of adipose tissue treatment with a noncontact field RF system delivering 200 W for 30 min and 300 W for 20 min: An in vivo porcine study

BACKGROUND AND AIMS

Abdominal circumferential reduction with noncontact high frequency apoptosis-inducing field RF (AiRF) is becoming very popular. The present study compared the treatment results from two different sets of parameters giving the same dose from the same system in an in vivo porcine model.

MATERIALS AND METHODS

Two 10 cm × 10 cm areas were symmetrically marked on both sides of the midline (total of 4 areas) over the rectus abdominis muscle of two anesthetized female micropigs. In Animal A (G1), 27.12 MHz AiRF treatment was given at 200 W for 30 min, and 300 W for 20 min in Animal B (G2). Four sessions were performed at weekly intervals. Gross observation by a veterinary specialist was performed on a daily basis. Temperature measurements (fat and skin), clinical photography and ultrasound imaging were carried out at each session. In addition, blood chemistry was performed before each session to check lipid levels, any adverse changes in markers for liver damage in addition to an enzyme-linked immunosorbent assay (ELISA) for raised levels of TNF-α and IL-1β. Biopsies were taken and routinely processed for hematoxylin and eosin, Toluidine blue and oil red O stains to examine for tissue damage at baseline and after each treatment. TUNEL assays were performed to check of apoptotic-related DNA damage. Follow-up assessments included photography, ultrasound, ELISA tests and biopsies which were taken regularly up to 90 days after the final treatment.

RESULTS

The maximum adipose tissue temperatures at and over the apoptotic threshold of 43°C were reached and maintained in both G1 and G2. The skin surface temperature was slightly higher in G2 after 20 min than in G1 after 30 min, but was still below 43°C. Gross and magnified observation revealed no appreciable differences or thermally-mediated damage between the skin of either of the two groups after the treatments or during the 90-day follow-up period. No lasting erythema or any other adverse event was seen in either group. The liver enzyme markers showed very similar patterns over the 4 weeks of treatment compared with baseline with no levels outside of the normal range. Triglycerides were all within normal rage with no significant differences between the groups. Remarkably similar patterns were noted for the ELISAs in both groups performed over the 4 weeks of treatment and at periods during the 90-day follow-up with no notable abnormal changes in levels. Staining patterns for both G1 and G2 specimens were similar for all stain types during treatment and the 90-day follow-up, showing decreased numbers of adipocytes by the 90-day point. The ultrasound findings revealed a 44.8% and 55.6% decrease in the adipose layer for G1 and G2, respectively, at the 90-day assessment.

CONCLUSIONS

The 200 W AiRF treatment for 30 min (G1) and the 300 W AiRF treatment for 20 min (G2) produced very similar results in the porcine model for all assessments and at all assessment points during and up to 90 days after treatment, with slightly better findings suggested for G2. Based on the above findings, the two different settings, delivering the same dose, produced good results with no skin damage and no adverse events. This has implications in busy clinics for AiRF treatment, where the shorter treatment time could represent time saving for the clinic and the patient without compromising safety and giving equal if not better efficacy.

Gold nanobipyramid Q-switched Nd:LGGG eye-safe laser operating at 1423.4 nm

The performance of a laser-diode-pumped passively Q-switched Nd:LGGG laser at 1423.2 nm with gold nanobipyramids (Au-NBPs) as a saturable absorber was demonstrated. An average output power of 125 mW was obtained at a pump power of 12.2 W, corresponding to an optical-to-optical conversion efficiency of 1.36% and a slope efficiency of 1.78%. A minimum pulse width of 514 ns at a pulse repetition rate of 98.6 kHz was obtained at a pump power of 12.2 W. To the best of our knowledge, this is the first report focusing on the application of Au-NBPs as a saturable absorber for pulse laser operation in the eye-safe region.

Graphene Q-switched eye-safe Nd:Y(3)A(l5)O(12) ceramic dual-wavelength laser

With graphene as a saturable absorber, the efficient and stable 1.4 μm dual-wavelength operation of Nd:YAG ceramic laser is demonstrated. A maximum total average output power of 601 mW is obtained under the pump power of 22.3 W, corresponding to an optical-optical conversion efficiency of 2.7%. The minimum pulse width and the highest pulse repetition rate are 470 ns and 101 kHz, respectively.

Minimally Invasive Surgery for Axillary Osmidrosis Using a Combination of Subcutaneous Tissue Removal and a 1,444-nm Nd:YAG Laser

Many treatment modalities have been developed for axillary osmidrosis. It is well known that the surgical treatment has the best results. However, there is a high possibility of side effects. The 1,444-nm lipolysis laser has been recently introduced to remove the apocrine glands. So far, subdermal coagulation treatment with a 1,444-nm Nd:YAG laser may be the least invasive and most effective therapy for axillary osmidrosis. However, according to our previous experience, the recurrence rate was 20%~30%. This emphasizes the need for combination of surgical method and non-surgical method and we combined subcutaneous tissue removal and photothermocoagulation with a 1,444-nm Nd:YAG laser. Three patients for bilateral axillary osmidrosis were enrolled. After an incision of about one-third the length of the widest transverse diameter, the apocrine glands were separated from the skin. And then apocrine glands within the marked area were destroyed by irradiation with a 1,444-nm Nd:YAG laser thereafter. All patients exhibited no relapse of axillary osmidrosis and were satisfied with the treatment results. A combination of subcutaneous tissue removal and Interstitial laser photothermocoagulation with a 1,444-nm Nd:YAG laser could be an effective treatment for mild to moderate axillary osmidrosis.

The skin-tightening effects of 1,444-nm Nd:YAG laser on human skin: an in vivo study

BACKGROUND

The 1,444-nm Nd:YAG laser was developed to improve the removal of fat cells and to affect the underlying dermis with the aim of skin tightening. We conducted this study to evaluate whether this laser is effective in tightening the skin and causing histological alterations to dermal collagen fibers, fibroblasts, mucopolysaccharides, and elastin.

METHODS

In a 38-year-old patient who was scheduled to undergo elective abdominoplasty, we subdermally performed laser-assisted treatment with the 1,444-nm Nd:YAG laser using different power settings over periods of 3 months and 1 month and prior to surgery. Postoperatively, we evaluated the skin-tightening effect through histopathologic examination.

RESULTS

On histopathology examination, the thickness of the dermis had gradually increased following the 3-month treatment with laser irradiation. In the treatment groups on the abdomen, the collagen fibers were arranged in a more parallel pattern and became denser than those in the control group. Likewise, fibroblast proliferation and the levels of mucopolysaccharides and elastin were higher in the treatment groups than in the control group.

CONCLUSIONS

The 1,444-nm Nd:YAG laser was effective in promoting the remodeling of the dermis and the regeneration of collagen fibers. As such, the 1,444-nm Nd:YAG laser could be used for skin tightening in addition to its function in lipolysis.

LEVEL OF EVIDENCE II

This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

A Prospective, Long-Term Follow-Up Study of 1,444 nm Nd:YAG Laser: A New Modality for Treating Axillary Bromhidrosis

BACKGROUND

Surgery for bromhidrosis has a high risk of complications such as hematoma and necrosis. New nonsurgical methods may reduce the burden on surgery and the risks for the patient.

OBJECTIVE

This study was performed to evaluate the efficacy and side-effects of the 1,444 nm Nd:YAG interstitial laser for treating axillary bromhidrosis.

METHODS

Eighteen bromhidrosis patients were treated with a 1,444 nm Nd:YAG laser at Korea University Ansan Hospital. The post-treatment follow-up was 6 months. After the procedure, we confirmed apocrine gland destruction through histopathological examination. At each follow-up, we measured the severity of the remaining odor, postoperative pain, degree of mobility restriction, and overall satisfaction.

RESULTS

After 180 days of follow-up, malodor elimination was good in 20 axillae, fair in 12 axillae, and poor in four axillae. At the end point of the study, 14 patients were totally satisfied with the laser treatment, three patients were partially satisfied, and one patient was disatisfied. Pain and limitation of mobility were significantly reduced within 1 week post-operatively, and were almost resolved within 4 weeks post-operatively. A histopathological examination revealed decreased density and significant alterations to the apocrine glands.

CONCLUSION

Subdermal coagulation treatment with a 1,444 nm Nd:YAG interstitial laser may be a less invasive and effective therapy for axillary bromhidrosis.

Subdermal Coagulation Treatment of Axillary Bromhidrosis by 1,444 nm Nd:YAG Laser: A Comparison with Surgical Treatment

Bromhidrosis is a disease presenting as malodor caused by interaction between the discharge of apocrine glands and bacteria. The main therapeutic modalities are applying topical agents, liposuction surgery, and elective surgery. Among these, elective surgery is reported to be most effective. However, the efficiency largely depends on surgical technique. Additionally, other side effects, such as hematoma and scarring, are occasionally reported. Currently, CO2 laser and 1,064 nm Nd:YAG laser therapy are used, but as the wavelength is not specific to apocrine glands, these laser therapies have certain limitations. Recently, a 1,444 nm wavelength Accusculpt™ laser (LutronicCorp., Seoul, Korea) has been developed which is now commonly used for facial fat plasty and laser liposuction therapy. The use of this laser for bromhidrosis therapy targeting apocrine sweat glands is currently being discussed. Still, no studies on practical clinical use and side effects of this 1,444 nm wavelength laser have been published. In this report, we treated one bromhidrosis patient with 1,444 nm wavelength Accusculpt™ laser therapy on one side while conventional surgery was performed on the other side using a modified Inaba's method. We compared the efficacy of this laser therapy to the surgical modality by measuring malodor severity and overall satisfaction by questionnaire. We also checked for other complications and recurrence for 12 months after the treatment. This patient was largely satisfied as it has a much shorter down time with the same therapeutic outcome. As subdermal coagulation treatment by 1,444 nm Nd:YAG laser may be less invasive but effective therapy, we would like to recommend this modality as a possible treatment option.

Passively Q-switched performance of a Nd:Gd3Ga5O12 eye-safe laser at 1423.4 nm with Co2+:LaMgAl11O19 as saturable absorber

The performance of a LD-pumped passively Q-switched Nd:GGG eye-safe laser at 1423.4 nm with a Co(2+):LaMgAl(11)O(19) (Co:LMA) saturable absorber is demonstrated. A maximum average output power of 627 mW with an optical-to-optical efficiency of 3.35% and a slope efficiency of 5.1% was obtained under a pump power of 18.7 W. A minimum pulsewidth of 102 ns and a pulse repetition rate of 35 kHz were obtained with the T=1.0% output coupler.

Preliminary experience in facial and body contouring with 1444 nm micropulsed Nd:YAG laser-assisted lipolysis: A review of 24 cases

BACKGROUND AND AIMS

Near-infrared laser-assisted lipolysis has claimed attention recently as a fast, safe and effective way to remove unwanted fat from various areas of the body. Removal of fat from the face has however proved more difficult. A novel 1444 nm line of the micropulsed Nd:YAG has recently been developed, offering superior duality of absorption in both fat and water. The present preliminary study was designed to assess the efficacy of the 1444 nm wavelength in facial and body contouring.

SUBJECTS AND METHODS

Twenty-four informed and consenting female patients (ages ranging from 23 yr to 59 yr, mean age 32.38 ± 7.26 yrs) were recruited into the study. The laser used was a micropulsed 1444 nm Nd:YAG system. Following tumescent anesthesia, the tip of the optical fiber was placed in the subcutaneous fat via a cannula inserted through a small puncture wound, and lasing was commenced while the tissue over the end of the optical fiber was continuously palpated to check for excessive heat formation. Cold compresses were applied post-lasing. Patients were followed for at least 2 months with clinical photography at baseline, immediately post-treatment and at subsequent assessment points.

RESULTS

All patients successfully completed the study. Patient subjective satisfaction was high, and an objective clinician assessment from the clinical photography showed good efficacy. There were no major adverse side effects. Minor side effects were transitory, all resolved spontaneously and good results were maintained during a 2-3-month follow-up.

CONCLUSIONS

The present study showed high efficacy for the 100 μs micropulsed Nd:YAG laser at 1444 nm for laser-assisted lipolysis of both body and facial areas, with no adverse side effects and virtually no downtime. The high absorption rate of 1444 nm in both fat and water, coupled with the 100 μs pulse, was believed to contribute highly to the success of the study and the satisfaction of the patients. Further larger studies are warranted.

High efficiency Nd:YAG ceramic eye-safe laser operating at 1442.8 nm

We report on a diode-pumped Nd:YAG ceramic laser operating at 1442.8 nm for the first time. In our experiment, two different Nd:YAG ceramics with the Nd-doped concentrations of 1.0 and 0.6 at. % and a Nd:YAG with the Nd-doped concentration of 1.0 at. % were used as the laser gain mediums, respectively. At a pump power of 20.7 W, a maximum output power of up to 3.96 W with optical-to-optical efficiency of up to 19.1% was obtained by using the 1.0 at. % Nd-doped ceramic as the laser gain medium. To the best of our knowledge, this is the highest output power of a LD-pumped 1.44 μm Nd:YAG ceramic laser and the highest optical-to-optical efficiency of a LD-pumped 1.44 μm Nd-doped crystal laser.

High-efficiency continuous-wave Nd:Gd3Ga5O12 eye-safe laser operating at 1423.4 nm

A Nd:Gd3Ga5O12 (Nd:GGG) laser operating at a wavelength of 1423.4 nm was demonstrated, which has not yet been reported, and is of great interest for wide application potential. With a pumped power of 18.5 W, a maximum output power of 3.63 W was obtained, corresponding to an optical-to-optical efficiency of 19.6% and a slope efficiency of 26%. These unique characteristics of a Nd:GGG laser at 1423.4 nm thereby open new opportunities for a light source in the field of medicine.

Histological evaluation of dermal tissue remodeling with the 1444-nm neodymium:yttrium-aluminum-garnet laser in in vivo model

Laser lipolysis has a skin tightening effect by heating the deep dermis, in addition to the removal of fat tissues. The 1444-nm neodymium:yttrium-aluminum-garnet (Nd:YAG) laser has been expected to be more effective and safe for laser lipolysis, due to higher affinity to fat and water, than 1064-nm and 1320-nm wavelengths. The purpose of this study was to evaluate the skin tightening effect of the 1444-nm Nd:YAG laser through in vivo guinea pig models. The 1444-nm Nd:YAG laser was used to irradiate shaved dorsal skin of the guinea pigs and compared with controls (no power, only tunneling). Immediately, 1 week, 1 month and 3 months after laser administration, full-thickness skins were harvested and to evaluate dermal thickness, collagen organization, fibroblast proliferation, and intensity of elastic fibers and mucopolysaccharides, using hematoxylin-eosin, Masson-trichrome, Verhoeff's stain and Alcian blue stain. Dermal thickness showed an increase with time in all groups. In collagen organization, fibroblast proliferation, and intensity of elastic fibers and mucopolysaccharides, the treatment groups were higher than those of the control group, overall. Our study showed that the 1444-nm Nd:YAG laser appeared to be effective for the skin tightening effect in in vivo guinea pig models. The 1444-nm Nd:YAG laser can be used for skin tightening, as well as reduction of fat tissues.

Early clinical experience with the 1440-nm wavelength internal pulsed laser in facial rejuvenation: two-year follow-up

This article reports on the early experience with the 1440-nm wavelength, using a specially designed side-firing fiber, in a four-step approach, primarily to the lower third of the midface and neck. The author presents the clinical protocol, procedure steps, outcomes, and adverse events of use of the laser. Outcomes are described at 3 months, 6 months, and 18 months.

Ablation efficiency and relative thermal confinement measurements using wavelengths 1,064, 1,320, and 1,444 nm for laser-assisted lipolysis

Laser-assisted lipolysis is routinely used for contouring the body and the neck while modifications of the technique have recently been advocated for facial contouring. In this study, wavelength-dependence measurements of laser lipolysis effect were performed using different lasers at 1,064, 1,320, and 1,444 nm wavelengths that are currently used clinically. Fresh porcine skin with fatty tissue was used for the experiments with radiant exposure of 5–8 W with the same parameters (beam diameter = 600 μm, peak power = 200 mJ, and pulse rate = 40 Hz) for 1,064, 1,320 and 1,444 nm laser wavelengths. After laser irradiation, ablation crater depth and width and tissue mass loss were measured using spectral optical coherence tomography and a micro-analytical balance, respectively. In addition, thermal temporal monitoring was performed with a thermal imaging camera placed over ex vivo porcine fat tissue; temperature changes were recorded for each wavelength. This study demonstrated greatest ablation crater depth and width and mass removal in fatty tissue at the 1,444 nm wavelength followed by, in order, 1,320 and 1,064 nm. In the evaluation of heat distribution at different wavelengths, reduced heat diffusion was observed at 1,444 nm. The ablation efficiency was found to be dependent upon wavelength, and the 1,444 nm wavelength was found to provide both the highest efficiency for fatty tissue ablation and the greatest thermal confinement.