The effect of 112mJ Nd: YAG laser irradiation on structural, morphological, infrared and magnetic properties of Ni1+xZrxFe2–2xO4 spinel ferrite nanoparticles has been systematically investigated in ...the present work. The sol-gel auto combustion synthesis method was successfully executed for the synthesis of the present system. All the samples were characterized by X-ray diffraction technique (XRD), scanning electron microscopy (SEM) and infrared spectroscopy (IR) technique. The magnetic properties of the present samples were measured by pulse field hysteresis loop technique. All the properties were measured for laser irradiated samples as well, to understand the effect of irradiation on the properties. The single-phase cubic spinel structure was confirmed by X-ray diffraction patterns of all samples and the disordered structure was observed for irradiated samples. The two principle absorption bands in IR spectra also confirm the formation of the spinel structure. Spherical and agglomerated morphology was observed for Zr4+ substituted nickel ferrite, whereas scratched morphology was observed for the irradiated samples. The grain size confirms the nanocrystalline nature, the crystallite size also evident the same. The magnetic parameters decreased after Zr4+ ion doping and strongly influenced by the irradiation.
•The 112mJ Nd: YAG laser irradiation and Zr substitution can alter the properties of nickel ferrite nanoparticles.•High crystallinity and small crystallite size were observed in irradiated material.•Morphology of the samples damaged after irradiation.•The magnetic parameters were found to enhanced remarkably after irradiation.
Summary
Backgrounds
Treatment of mixed melasma remains challenging. Promising results have been achieved with low‐fluence 1064‐nm Q‐switched Nd‐YAG laser; however, multiple sessions are necessary ...with occurrence of complications especially in dark skin types. So, combination methods may be recommended.
Aims
To compare efficacy of Q‐switched Nd‐YAG laser alone or with modified Jessner's peel in mixed melasma in dark skin.
Patients/Methods
Nineteen patients with mixed melasma received 6 sessions of laser on left side of face and alternating laser and modified Jessner on right side. Evaluation was carried out clinically through modified melasma area and severity index at 1 month after last session. Using histopathological, immunohistochemical, and computerized morphometric analysis, objective evaluation of melanin particle surface area and MART‐1‐positive cells was performed for pre‐ and post‐treated skin biopsies.
Results
There was significant clinical improvement on both sides of face (P < .001), without significant difference (P > .05). At the sixth laser session on left side of face, ill‐defined mottled hypopigmentation was observed in 21.05% of patients. Histopathologically, melanin particle surface area and number of MART‐1‐positive cells (total, epidermal, and dermal) were significantly decreased after two treatment modalities (P < .001), without significant difference in their reduction percentage between both sides of face (P > .05).
Conclusion
Low‐fluence Q‐switched Nd‐YAG laser alone and with modified Jessner's peel are equally effective regimens for mixed melasma clinically, histopathologically, and immunohistochemically. However, combined method is preferred, especially in dark skin, for obtaining better cosmetic result with fewer side effects of multiple laser sessions and decreasing cost rate of laser.
Acral warts are considered as prevalent reasons for dermatologic consultations and remain an important continuing challenge until now because there is no consensus about optimal therapeutic modality. ...This study investigated the efficacy of long-pulsed Nd: YAG laser therapy and cryotherapy in treatment of acral warts. Patients who underwent treatment with cryotherapy or long-pulsed Nd: YAG laser therapy for symmetrical and bilateral warts on the extremities (hand and foot) that is confirmed by an expert dermatologist from May 2016 until March 2018 were assessed for enrollment in our study. Laser and cryotherapy sessions were applied every 2 weeks for a maximum of six sessions. Patients followed up and evaluated 3 months after the last treatment. Data were analyzed by SPSS (v.21. IBM Inc. IL). The
P
value less than 0.05 was considered significant. From 60 enrolled patients, 134 lesions were treated using cryotherapy and 114 other lesions treated with laser beam. Thirty-four males (average age 26.85 ± 7.528 years) and 26 females (average age 26.73 ± 5.640 years) participated. Finally, it was a significant reduction in both lesion width (
P
= 0.000) and length (
P
= 0.000) after the sessions of cryotherapy. The width and length of lesions is reduced significantly after each session of laser therapy similarly (
P
= 0.000). Cryotherapy and long-pulsed Nd: YAG laser are effective on the reduction of both width and length of lesions. Clinically, the methods are not different in their ultimate effects.
Aim
The purpose of this study is to identify the effect of Nd: YAG laser posterior capsulotomy using an anterior chamber morphology.
Methods
This study included 42 eyes of 33 pseudophakic patients ...with visually significant PCO after uncomplicated cataract surgery. Exclusion criteria were complications related to cataract surgery, corneal pathology, pseudoexfoliation, glaucoma, uveitis, previous ocular surgery or trauma, and posterior segment pathology. All patients underwent routine ophthalmic examinations. The AS-OCT measurements were performed using NIDEK RS-3000 Lite retinal scan with anterior segment module. The anterior chamber depth (ACD) was measured by Monitor A&B Scan biometer. Nd: YAG laser posterior capsulotomy was done in a single session by the circular pattern with rupture of vitreous strands. Anterior chamber depth (ACD), central corneal thickness (CCT), and intraocular pressure (IOP) were measured. Anterior chamber angle (ACA), angle opening distances (AOD) at 500 mm (AOD500), AOD at 750 mm (AOD750), trabecular-iris space area at 500 (TISA 500), and TISA at 750 (TISA 750) were measured both nasally and temporally.
Results
The mean patient age was 55.56 ± 6.33 years. There were non-significant changes in IOP, ACD, and CCT with
P
values 0.395, 0.153, and 0.541, respectively. ACA, AOD500, AOD750, TISA 500, and TISA 750 highly significantly increased with
P
value < 0.001 for all.
Conclusion
Nd: YAG laser posterior capsulotomy with the circular pattern with vitreous strand cut technique is a safe technique for laser posterior capsulotomy.
The micromachining of NiTinol shape memory alloy is exceptionally demanded in industry on account of its wide and expected use in different fields like aviation, biomedical designing. NiTinol shape ...memory alloy has enormous application in the vehicle and assembling industry. It accomplishes response surface methodology (RSM) approach based on numerical demonstrating of the machining qualities of the pulsed Nd:YAG laser during micro-channelling operation on 1 mm thick NiTinol shape memory alloy sheet. The tests were arranged and done in light of box-behnken design of experiments. Scanning speed, pulse width, frequency and current were the input parameters investigated in this study and furthermore, these parameters were also used to foster the RSM model. The reaction measures choose for the enhancement of upper width deviation (UWD) and lower width deviation (LWD) of the micro-channelling. Based on the experimental box-behnken design (BBD), micro channelling was performed on NiTinol sheet. The results reveal that the input parameters have a considerable impact on the quality of the micro channel. The ideal input parameter for the desired output parameters is found through particle swarm optimisation. The upper and lower width deviation were discovered with the use of a scanning electron microscopic images.
We develop a quasi-steady-state thermal model to analyze transient thermal effects in a Nd :YAG laser rod under quasi-continuous laser-diode (LD) end pumping. Included is a quasi-adiabatic model for ...pump durations and a quasi-steady-state heat dissipation model for pump-free durations. We give an approximate expression of the transient temperature-difference distribution function of the crystal under quasi-continuous pumping. The method for calculating the transient thermal focal length is also presented. On this basis, the temperature distribution variation in the crystal with time and the variation range of the transient thermal focal length are quantitatively analyzed. For 50 W, 200 μs pulse-width, and 50 Hz pumping, the temperature at the center of the Nd:YAG rod has a range of 304.52 – 306.28 K, and the thermal focal length varied over 1612.8 – 310.43 mm. Both have saw-tooth periodic distributions. This study provides a theoretical reference for the design of laser-diode-pumped thermal
Q
-switched Nd :YAG lasers.
Surgical treatment remains the first-line therapy of pilonidal cyst but is associated with high levels of postoperative pain, adverse events and a recurrence rate of 30%. We report our experience ...with laser hair removal using the Nd-YAG laser for the treatment of pilonidal cyst.
Ten patients affected by pilonidal cyst were examined and treated from October 2011 to November 2016. Treatments were carried out using the Nd-YAG laser (Deka M.E.L.A, Calenzano, Florence, Italy) at a wavelength of 1064 nm at 30-day interval.
Nine patients were asymptomatic after the second treatment, while in one case the symptom disappeared after the fourth session. After 4-8 treatments, the pilonidal cyst had clinically disappeared and patients subjectively felt healed. In all cases, the soft-tissue ultrasounds performed before the first and after the last session showed the disappearance of the pilonidal cyst. In the follow-up, all the patients remained asymptomatic without any disease recurrence.
Nd-YAG laser is an effective treatment for pilonidal cysts, providing excellent results with quick healing and no risk of serious adverse side-effects. It could be a very attractive alternative to open surgery, enabling patients to prevent the frequent and severe postoperative issues associated with surgery.
Pyogenic granuloma (PG) is a common benign vascular proliferation which often occurs on the head, neck, hands, and feet. Among the various treatment options for PG, surgical excision is the most ...effective treatment which offers the lowest overall recurrence rates and also provides the exact diagnosis. However, it could have difficulties to do the surgery when lesions are located on the fingers and toes, especially very near to the nails, so laser may be a very good alternative choice. In this article, we evaluated the clinical efficacy and safety of neodymium-yttrium aluminum garnet (Nd:YAG) laser for treatment of PG located on the fingers and toes. Twenty-one patients with 21 PGs located on the fingers and toes were treated by multispot Nd-YAG laser. We chose monopulse (pulse width 10.5–13.5 ms; energy 100–125 J/cm
2
); treatment interval was 3–4 weeks. All lesions disappeared after one or two treatments. There was no apparent scar formation, no impact on the function of the fingers and toes, no damage to nail growth, and no recurrence in more than 12-month follow-up. Nd-YAG is an effective and safety treatment option for treatment of PG located on the fingers and toes.
Background
Nanosecond quality‐switched ruby laser (QSRL) and frequency‐doubled 532‐nm picosecond Nd:YAG laser (532‐nm picosecond Nd: YAG laser PSNYL) are well‐documented treatments for solar ...lentigines (SLs). However, no studies have longitudinally tracked the microscopic findings before and after QSRL and 532‐nm PSNYL treatment for SL removal.
Objectives
To compare the clinical efficacy and dynamic histological changes between QSRL and 532‐nm PSNYL in the treatment of SLs in Asian patients.
Method
Twenty‐five patients with SLs on both sides of the face were enrolled in this prospective split‐face study. QSRL and 532‐nm PSNYL therapy for SLs on the left and right side of the face, respectively, were performed for each subject. All subjects underwent baseline and follow‐up assessment at Weeks 3 and 6. In vivo harmonic generation microscopy (HGM) imaging was adopted for the noninvasive observation of melanin mass density of basal cells (MMDbasal cell), epidermal melanocyte dendricity, and dermal melanophages before and after laser treatment.
Results
At Week 6, 60% of the lesions treated with QSRL and 68% with 532‐nm PSNYL had over 75% improvement. Histologically, both lasers resulted in statistically significant decrease of MMDbasal cell in SLs to the level of that in the normal skin at Weeks 3 and 6. Statistically significant increase of dermal melanophages was observed 3 weeks after both laser treatments. Nevertheless, 532‐nm PSNYL led to faster clearance of melanophages than QSRL at Week 6. Moreover, activated melanocytes with enhanced dendrite formation was significantly increased till 6 weeks after both laser treatments.
Conclusion
Both QSRL and 532‐nm PSNYL were effective treatments for SLs, and there was no statistically significant difference in clinical scoring. However, from histological aspect, 532‐nm PSNYL was associated with lower degree of melanin incontinence and melanophage accumulation. HGM imaging analysis can noninvasively quantitate the cutaneous response to pigmentary laser therapy.
