Endovenous laser treatment vs conventional surgery for great saphenous vein varicosities: A propensity score matching analysis

BACKGROUND Varicosis is a common venous condition,which is typically treated surgically.However,selection of the optimal surgical approach can be challenging.Previous studies comparing endovenous laser treatment(EVLT)and conventional surgery were retrospective and observational in nature and the results may therefore have been influenced by selection bias and the presence of other confounding factors.In this study,we used propensity score matching to reduce selection bias when comparing EVLT and conventional surgery for the treatment of varicose great saphenous veins.METHODS We retrospectively reviewed the records of 1063 patients treated for primary varicosis of the great saphenous vein at the Second Affiliated Hospital of Xuzhou Medical University between January 2009 and December 2019.Among them,56 patients were excluded owing to additional small saphenous varicose vein involvement,81 owing to recurring varicose veins,83 owing to complicated varicose veins(CEAP clinical classification C5-C6),and 6 owing to perioperative phlebitis.Finally,772 patients were enrolled in this study.Standard demographic and clinicopathological data were collected from the medical records of the patients.For propensity score matching,522 patients(261 who underwent EVLT and 261 who underwent conventional surgery)were randomly matched 1:1 by age,sex,onset time,smoking status,presence of diabetes,family history,stress therapy,C class,and the affected leg.RESULTS Of the 772 patients included in the study,467 underwent EVLT and 305 underwent conventional surgery.There were significant differences in age,onset time,smoking and diabetes status,and family history between the two groups.Following propensity score matching,no significant differences in patients’characteristics remained between the two groups.ELVT was associated with a shorter operation time and hospital stay than conventional surgery,both before and after propensity score matching.There were no differences in complications between the two groups after propensity score matching.Patients who underwent EVLT had a higher recurrence rate during the two-year follow-up period than those who underwent conventional surgery(33.33%vs 21.46%,χ^(2)=11.506,P=0.001),and a greater percentage of patients who underwent EVLT experienced pain one week after the procedure(39.85%vs 19.54%,P=0.000).CONCLUSION EVLT may not always be the best option for the treatment of great saphenous vein varicosis.

Influence of laser treatment on the fatigue of notched bar

Fatigue cutting is a new approach for separating material. Man-made fatigue can be realized by applying a rotating bending load to a notched bar. To better utilize the new method, laser treatment is adopted in this study. After laser radiation at the notch root, the fatigue cycle of the bar drops dramatically. Based on the experimental result, we draw the conclusion that the fatigue of the bar is influenced by the shape of the hardened area. A hardened area that has a small axial dimension and a relatively large radial dimension facilitates the fatigue. The desirable hardened area can be obtained by controlling the laser treatment parameters.

Effects of low level laser treatment on the survival of axotomized retinal ganglion cells in adult Hamsters

Injury to axons close to the neuronal bodies in the mammalian central nervous system causes a large proportion of parenting neurons to degenerate. It is known that optic nerve transection close to the eye in rodents leads to a loss of about half of retinal ganglion cells in 1 week and about 90% in 2 weeks. Using low level laser treatment in the present study, we demonstrated that treatment with helium-neon （660 nm） laser with 15 mW power could delay retinal ganglion cell death after optic nerve axotomy in adult hamsters. The effect was most apparent in the ifrst week with a short period of treatment time （5 minutes） in which 65–66% of retinal ganglion cells survived the optic nerve axotomy whereas 45–47% of retinal ganglion cells did so in optic nerve axotomy controls. We also found that single dose and early commencement of laser irradiation were important in protecting retinal ganglion cells following optic nerve axotomy. These ifndings thus convincingly show that appropriate laser treatment may be neuroprotective to retinal gan-glion cells.

Clinical Effect of Laser Treatment Combined with Compound Xueshuantong Capsule in the Treatment of Diabetic Retinopathy

Objective:To determine the clinical value of compound Xueshuantong capsule in the treatment of diabetic retinopathy on the basis of laser treatment.Methods:Data were collected from 98 patients with diabetic retinopathy from February 2021 to February 2022.They were divided into two groups by drawing lots.The experimental group was treated with compound Xueshuantong capsule and laser treatment,whereas the control group was treated with laser treatment alone.Results:The absorption of exudation,resolution of retinal edema,and absorption of bleeding took longer in the control group;the incidence of visual acuity recovery to more than 0.5 and the patients’blood glucose levels were better in the experimental group,p<0.05.Conclusion:For patients with diabetic retinopathy,laser treatment combined with compound Xueshuantong capsule can effectively improve the visual function and rehabilitation efficiency of patients with diabetic retinopathy as well as stabilize their blood sugar levels.It has high clinical application value.

Surface Roughness Modification of Free Standing Single Crystal Silicon Microstructures Using KrF Excimer Laser Treatment for Mechanical Performance Improvement

Single crystal silicon freestanding structures for tensile and fatigue testing were treated with KrF excimer laser to improve surface roughness and accordingly mechanical performance. Sample thickness was 5 μm. Localized laser treatment was successful in eliminating the scallops developed during Bosch process and in reducing surface roughness. Harsh irradiation at laser energies up to 4 J/cm2 was only possible due to localized treatment without significant vibrations occurring on the freestanding samples that led to fracture in preliminary experiments at energies as low as 0.16 J/cm2. Finite element analysis was used to investigate the temperature distribution on the irradiated structures. Atomic force microscopy (AFM) and Raman spectroscopy were also used to assess surface roughness, crystallinity changes and surface stresses developing on surfaces subjected to perpendicular laser irradiation. At a high energy (3.2 J/cm2) the top surface showed a decrease of roughness compared to fabricated samples. Raman spectroscopy showed the dominance of crystalline silicon after laser irradiation. The effects of laser energy, number of

Nd:YAG Laser Treatment for Valsalva Premacular Hemorrhage

Purpose:To report a case of Valsalva premacular hemorrhage treated by Nd:YAG laser.Methods:.A patient who presented with Valsalva premacular hemorrhage was treated with photodisruptive Nd:YAG laser to drain the entrapped premacular blood into the vitreous.Results:After photodisruption,vision in the affected eye improved rapidly due to exposure of the macula.Conclusion:.Nd:YAG laser treatment may be a good alternative for recent preretinal hemorrhages.Clinical benefits include rapid visual rehabilitation and the avoidance of vitrectomy.

The Effect of MgO Dopant and Laser Treatment on ZnO Ceramic

ZnO ceramic samples as pellets have been prepared and doped with (1, 2.5, 5, 10 wt%) of MgO powder, sintering at 1300?C, these samples have been treated with laser at 400 J/cm2. X-ray diffraction spectra of the samples show some changes in the X-ray parameters, where d-spacing and the intensities of the peaks are changed. FWMH of all the samples was altered due to MgO dopant and the laser influence microstructure was affected by the laser treatment, also, the texture coefficient is affected.

Comparison of structural outcome between intravitreal bevacizumab and laser treatment for type 1 retinopathy of prematurity after long-term follow-up

Background:To compare the structural outcome of intravitreal bevacizumab(IVB)and laser treatment for type 1 retinopathy of prematurity(ROP).Methods:This is a retrospective comparative study.From December 2002 to April 2009,patients with type 1ROP according to criteria of Early Treatment of Retinopathy of Prematurity(ETROP)study were treated by peripheral retinal diode laser photocoagulation in nearly confluent pattern.From May 2009 to January 2015,we performed IVB for patients with type 1 ROP.The patients were closely followed until disappearance of retinal neovascularization in the laser group and regression of avascular zone in the bevacizumab group.The demographical data,postmenstrual age(PMA)for treatment,and fundus findings were recorded by chart review.The difference between laser and bevacizumab groups was compared by Student t-test and Fisher exact test.Results:We collected 43 patients(86 eyes)with type 1 ROP,including 30 male and 13 female infants.Their mean gestation age and birth body weight(BBW)were 27.5 weeks and 1,034 gm.Zone I and zone II disease were found in 8 and 35 patients.The mean PMA for treatment was 37.3 weeks.The mean follow-up period was54.4 months.Laser treatment was administered in 26 patients,and bevacizumab injection for 17 infants.Single session of laser was performed in all patients of laser group without recurrence of retinal neovascularization.Complete regression of ROP was found in 15 infants of bevacizumab group following the first IVB.Four eyes in two patients(2/17,11.7%)had recurrence of ROP and received additional injections and adjuvant laser treatment.There was no unfavorable anatomical results such as retinal detachment or macular ectopia or complications such as cataract or endophthalmitis in either bevacizumab or laser management.Conclusions:Laser therapy and IVB were both effective treatments for type 1 ROP to cause favorable anatomical outcomes.Single session of laser ablation in nearly confluent pattern was sufficient for complete regression of ROP in laser group.Single IVB was appropriate for managing most of cases with ROP in bevacizumab group,but a small proportion(nearly one tenth)of them had recurrent episodes requiring adjuvant therapies.

Application of Endovenous Laser Treatment Combined with Foam Sclerotherapy for the Minimally Invasive Treatment of Great Saphenous Vein Varicosity

Objective:To evaluate the efficacy of endovenous laser treatment(EVLT)combined with foam sclerotherapy(FS)in the treatment of great saphenous vein varicosity(GSVV).Methods:A total of 50 patients with GSVV,treated between March 2021 and March 2024,were selected and randomly divided into two groups using a random number table.The combination group(25 cases)underwent EVLT combined with FS,while the conventional group(25 cases)underwent EVLT alone.The total effective rate,complication rate,disease severity score,and serological indicators were compared between the two groups.Results:The total effective rate in the combination group was higher,and the complication rate was lower compared to the conventional group(P<0.05).One week after surgery,the disease severity score in the combination group was lower,coagulation function indicators were better,and inflammatory factor levels were lower compared to the conventional group(P<0.05).Conclusion:EVLT combined with FS can improve the clinical efficacy in GSVV patients,prevent postoperative complications,reduce disease severity,protect patients’coagulation function,and alleviate postoperative inflammatory responses,showing significant advantages in combined surgery.

Combined subfascial endoscopic perforator surgery and endovenous laser treatment without impact on the great saphenous vein for management of lower-extremity varicose veins

Background Conventional high ligation and stripping of the great saphenous vein （GSV） has a good curative effect but is highly traumatic with a considerable relapse rate. Subfascial endoscopic perforator surgery （SEPS） plus endovenous laser treatment （EVLT） could be applied as individual therapy. This study aimed to evaluate the feasibility of performing combined SEPS and EVLT without impacting GSV in the management of valvular insufficiency of the lower-limb venous perforators. Methods Placement of lower-limb venous perforator insufficiency was marked by ascending phlebography in 83 affected limbs from September 2010 to June 2011. After randomization, SEPS was performed on 41 limbs to address the insufficiency of the venous perforators under the deep fascia, in combination with EVLT to close the superficial varicose veins without impacting the GSV. The remaining 42 limbs were treated using traditional GSV phlebectomy as controls. Results Postoperatively, all varicose veins were resolved, with lightening of the pigmentation and healing of the ulcer. Within a follow-up period of 5-11 months, no symptoms had recurred. Compared with the control group, the operation time, the number of incisions sutured, and the in-hospital time decreased on average by 1.5 hours, 4.7, and 6.8 days, respectively （P 〈0.01 in all cases）. Conclusion Combined SEPS and EVLT for treatment of valvular insufficiency of the lower-limb venous perforators offer the advantages of microtrauma and rapid cure.

Effects of diode laser photocoagulation treatment on ocular biometric parameters in premature infants with retinopathy of prematurity

AIM:To investigate the effects of diode laser treatment on ocular biometric parameters in premature infants with retinopathy of prematurity(ROP).METHODS:Premature infants who received diode laser treatment for ROP(n=68)and premature infants with spontaneous regressed ROP without treatment(n=50)were performed longitudinal ocular biometric measurements including anterior chamber depth,lens thickness and axial length as follows:1 d prior to laser treatment,and 3,6,9,and 12 mo after the laser treatment.RESULTS:The mean birth weight,gestational age and initial examination time values were 936.53±302.07 g,26.66±2.42 wk,36.26±2.73 wk in the treatment group and 959.78±260.08 g,27.28±2.10 wk,36.56±2.54 wk in the control group.There was no statistically significant difference in these demographic characteristics of the groups.Anterior chamber depth,lens thickness and axial length demonstrated statistically significant linear increases during the study period in the two groups(P<0.001 for each).There were no statistically significant differences between the two groups in terms of anterior chamber depth after laser treatment.Measurements of the lens thickness at 9 th and 12 th months(9 th month 3.70±0.22 vs 3.60±0.21 mm,P=0.017;12 th month 3.81±0.21 vs 3.69±0.22 mm,P=0.002)and the axial length at 12 th month(19.35±0.79 vs 19.13±0.54 mm,P=0.031)after laser treatment were statistically higher in the treatment group.CONCLUSION:Diode laser retinal photocoagulation treatment in premature infants seems to increase the lens thickness and axial length.

Long-term effect of prophylactic laser treatment for bilateral soft drusen

Background Large drusen is a known risk factor for the development of late complications of age-related macular degeneration （AMD） and drusen reduction has been found by our previous study. To prospectively evaluate the efficacy and safety of prophylactic laser treatment in Chinese patients with bilateral soft drusen, we examined the structure and function of the macula 8 years after treatment.Methods Ten patients with more than 10 soft drusen （〉125 mm） and best corrected visual acuity 〉20/25 in each eye participated in the study. One eye, with relatively more drusen, was exposed to an argon laser （514 nm） to achieve a barely visible retinal lesion. The contralateral eye was used as a control. Fluorescein angiography, Amsler tests,Fourier-domain optical coherence tomography and visual evoked potential tests were carried out 8 years later.Results No choroidal neovascularization was seen in the laser-treated eyes or control eyes. There were no significant differences in visual acuity or P100 latency and amplitude between the laser treated eyes and contralateral eyes （t=1.685,1.184; P〉0.05）. The thickness of the retinal pigment epithelium of the treated eyes was less than that of the contralateral eyes （t=-4.540; P 〈0.05）. The full retinal thickness in treated eyes was slightly, but insignificantly, reduced relative to contralateral eyes （t=-1.746; P 〉0.05）.Conclusions The treatment was associated with a reduction in retinal pigment epithelium thickness elevation compared with the contralateral eyes. Macular function was not impaired.

Current and emerging treatment for diabetic retinopathy in geriatric patients: a review

Diabetic retinopathy is a predictable effect of diabetes mellitus and is classified as a microvascular disease.The treatment of diabetic retinopathy is complex and challenging.Vascular endothelial growth factor therapy has demonstrated significant clinical improvement in visual outcomes.However,many patients fail to achieve visual improvement,necessitating the development of modern treatment techniques.Some experiments suggest that inflammation and retinal neurodegeneration may contribute to retinal damage in the early stages of diabetic retinopathy.This review aims to explore the current and emerging treatment options and pathophysiology of diabetic retinopathy.

Long-pulse Nd：YAG 1064-nm laser treatment for onychomycosis

Background Recent research shows that lasers can inhibit fungal growth and that Nd：YAG 1064-nm lasers can penetrate as deep as the lower nail plate. The aim of this study was to observe the effect of a long-pulse Nd：YAG 1064-nm laser on 154 nails of 33 patients with clinically and mycologically proven onychomycosis. Methods Thirty-three patients with 154 nails affected by onychomycosis were randomly assigned to two groups, with the 154 nails divided into three sub-groups （Ⅱ degree,Ⅲ degree, and IV degree） according to the Scoring Clinical Index of Onychomycosis. The 15 patients （78 nails） in group 1 were given eight sessions with a one-week interval, and the 18 patients （76 nails） in group 2 were given four sessions with a one-week interval. Results In group 1, the effective rates at 8 weeks, 16 weeks, and 24 weeks were 63%, 62%, and 51%, respectively, and the effective rates in group 2 were 68%, 67%, and 53% respectively. The treatment effect was not significantly different between any sub-group pair （P 〉0.05）. Conclusions Long pulse Nd：YAG 1064-nm laser was effective for onychomycosis. It is a simple and effective method without significant complications or side effects and is expected to become an alternative or replacement therapy for onychomycosis.

Microstructural characterization of Inconel 718 alloy after pulsed laser surface treatment at different powers

An annealed Inconel 718 alloy was surface-treated by pulsed laser at three different powers（100, 50 and 25 W）. Microstructural changes induced by the laser treatments were characterized by use of electron backscatter diffraction and electron channeling contrast imaging techniques. Results show that both annealing twins and strengthening precipitates profusely existing in the as-received specimen are dissolved at elevated temperatures during the laser irradiation. Meanwhile, in the melting zone（MZ）, densities of low angle boundaries（LABs） are greatly increased with a large number of Laves phases preferentially distributed along such LABs. For different specimens, widths and depths of their MZs are found to be gradually reduced with decreasing the laser powers. Orientation analyses reveal that the columnar grains in the MZ of the 100 W specimen could inherit orientations existing in the matrix while lower laser powers promote the formation of more nuclei with scattered orientations to grow to be granular grains in the MZ. Hardness tests reveal that the MZs of all laser-treated specimens are softer than the matrix probably due to both precipitate dissolution and grain coarsening.

Effects of laser heat treatment on salt spray corrosion of 1Cr5Mo heat resistant steel welding joints

The surface of 1Cr5 Mo heat-resistant steel welding joint was processed with CO2 laser, and the corrosion behaviors before and after laser heat treatment(LHT) were investigated in the salt spray corrosion environments. The microstructures, phases, residual stresses and retained austenite content of 1Cr5 Mo steel welding joint before and after LHT were analyzed with optical microscope and X-ray diffraction, respectively. The cracking morphologies and chemical compositions of corrosion products after salt spray corrosion were analyzed with field emission scanning electron microscopy(FESEM) and energy disperse spectroscopy(EDS), respectively, the polarization curves were measured on a PS-268 A type electrochemical workstation, and the mechanism of corrosion resistance by LHT was investigated as well. The results show that the passive film of original sample is destroyed owing to the corrosive media penetrating into the subsurface, resulting in the redox reaction. The content of residual austenite in the surface and the self-corrosion potential are increased by LHT, which is contributed to improving the capability of salt spray corrosion resistance.

A new model of selective photothermolysis to aid laser treatment of port wine stains

Pulsed dye lasers equipped with cryogen spray cooling(CSC) are now widely used to treat vascular malformation such as port wine stains(PWSs).This paper presents a new integrated model that can quantitatively simulate the cooling of the skin and the heating of the targeted blood vessels in PWSs during laser treatment.The new model is based on the classical homogeneous multi-layer skin model that treats PWS-containing dermis as a mixture of dermal tissue and homogeneously distributed blood.Light propagation in skin and PWSs is simulated by a Monte-Carlo method,which provides accurate description of the light scattering and absorption in the skin.Thermal response of a targeted vessel in the new model is then obtained from the thermal analysis of a Krogh-unit that consists of the vessel and the surrounding dermal tissues and is buried in PWSs.The results from the multi-layer skin model provide appropriate laser influence input as well as the initial thermal condition for the micro-model of the Krogh-unit.A general dynamic relation is also introduced on the surface of skin to quantify the convective cooling of CSC.The model is then applied to dye-laser treatment(wavelength of 585 nm) of PWSs with CSC.Numerical results demonstrate that the present model is able to quantify thermal response of a deeply buried blood vessel in PWSs as a discrete blood vessel does,with a more realistically estimate of the sheltering effect of the dermal tissue(scattering) and blood vessels(absorption) in front of the targeted vessel.To understand the poor response of PWSs in clinic,the thermal characteristics of a targeted vessel was simulated under various conditions.The effects of two morphological parameters,the vessel diameter and the burying depth of the vessel,are then systematically investigated under various pulse durations and fluences of laser.A threshold fluence for given vessel diameter and depth is then estimated quantitatively under the condition of the optimal laser pulse duration.The results indicate that significant high threshold fluence is needed for large vessels buried deeply in the dermis,explaining the physics of the difficulty in clinic of complete clearance of PWSs.The results provide guidance to the clinic selection of the laser pulse duration and laser energy fluence for given PWSs.

Influence of post-weld heat treatment on the microstructure and hardness of laser weld seams on hot-rolled TRIP 800 steel

The transformation induced plasticity (TRIP) steels effect occurs because of the martensitic transformation of retained austenite during plastic deformation,and it provides the steel with excellent strength and ductility.While welding remains a vital part of auto body manufacturing,the weldability of TRIP steels is problematic,and this prevents its adoption for many applications in the automotive industry.This present work studies the effects of welding and post-weld heat treatment on the microstructure of TRIP steels.It is found that the microstructures of the fusion zone and the heat affected zone (HAZ) are changed after high-temperature heat treatment.Hardness tests revealed that fusion zone hardness decreased with increasing of temperatures in the post-weld heat treatment on the laser weld seam.The rolling performance of the welding seam and the seam of post-weld heat treatment were also studied.

Noteworthy effects of a long-pulse Alexandrite laser for treatment of high-risk infantile hemangioma: A case report and literature review

BACKGROUND We have previously proved that treatment of thick/deep infantile hemangiomas (IHs) with a long-pulse Alexandrite laser was clinically effective and safe. This article aims to investigate the efficiency of long-pulse Alexandrite laser use in treating thick and high-risk IHs located in particular anatomic areas and provides some new data on this issue. CASE SUMMARY A two-month-old girl with a thick and high-risk IH covering most of the right labia majora was examined in this study. The infant received four treatment sessions at 4- to 6-wk intervals with a long-pulse Alexandrite laser with settings as follows: 3 ms pulse duration, 8 mm spot size, 45 to 50 J/cm2 fluences, and dynamic cooling device (DCD) spray duration of 90 ms with a delay of 80 ms. Following each of the four treatment sessions, the IH showed a remarkable reduction in thickness and size without any sign of relapse. Ten months after the last treatment, the IH had completely regressed without adverse effects. During the laser treatment, no severe side effects were observed;blistering occurred only immediately after treatment and then scabbed over the next day, gradually improving in the following days. CONCLUSION Long-pulse Alexandrite laser treatment may be considered one of the first-line noninvasive therapeutic options for the treatment of thick IH.