High-intensity focused ultrasound ablation:An effective bridging therapy for hepatocellular carcinoma patients

AIM:To analyze whether high-intensity focused ultrasound(HIFU) ablation is an effective bridging therapy for patients with hepatocellular carcinoma(HCC).METHODS:From January 2007 to December 2010,49 consecutive HCC patients were listed for liver transplantation(UCSF criteria).The median waiting time for transplantation was 9.5 mo.Twenty-nine patients received transarterial chemoembolization(TACE) as a bringing therapy and 16 patients received no treatment before transplantation.Five patients received HIFU ablation as a bridging therapy.Another five patients with the same tumor staging(within the UCSF criteria) who received HIFU ablation but not on the transplant list were included for comparison.Patients were comparable in terms of Child-Pugh and model for end-stage liver disease scores,tumor size and number,and cause of cirrhosis.RESULTS:The HIFU group and TACE group showed no difference in terms of tumor size and tumor number.One patient in the HIFU group and no patient in the TACE group had gross ascites.The median hospital stay was 1 d(range,1-21 d) in the TACE group and two days(range,1-9 d) in the HIFU group(P < 0.000).No HIFU-related complication occurred.In the HIFU group,nine patients(90%) had complete response and one patient(10%) had partial response to the treatment.In the TACE group,only one patient(3%) had response to the treatment while 14 patients(48%) had stable disease and 14 patients(48%) had progressive disease(P = 0.00).Seven patients in the TACE group and no patient in the HIFU group dropped out from the transplant waiting list(P = 0.559).CONCLUSION:HIFU ablation is safe and effective in the treatment of HCC for patients with advanced cirrhosis.It may reduce the drop-out rate of liver transplant candidate.

The feasibility and safety of high-intensity focused ultrasound combined with low-dose external beam radiotherapy as supplemental therapy for advanced prostate cancer following hormonal therapy

The aim of this study was to investigate the feasibility and safety of high-intensity focused ultrasound （HIFU） combined with （＋） low-dose external beam radiotherapy （LRT） as supplemental therapy for advanced prostate cancer （PCa） following hormonal therapy （HT）. Our definition of HIFU＋LRT refers to treating primary tumour lesions with HIFU in place of reduced field boost irradiation to the prostate, while retaining four-field box irradiation to the pelvis in conventional-dose external beam radiotherapy （CRT）. We performed a prospective, controlled and non-randomized study on 120 patients with advanced PCa after HT who received HIFU, CRT, HIFU＋LRT and HT alone, respectively. CT/MR imaging showed the primary tumours and pelvic lymph node metastases visibly shrank or even disappeared after HIFU ＋LRT treatment. There were significant differences among four groups with regard to overall survival （OS） and disease-specific survival （DSS） curves （P=0.018 and 0.015）. Further comparison between each pair of groups suggested that the long-term DSS of the H IFU ＋ LRT group was higher than those of the other three groups, but there was no significant difference between the HIFU＋LRT group and the CRT group. Multivariable Cox＇s proportional hazard model showed that both HIFU＋LRT and CRT were independently associated with DSS （P=0.001 and 0.035） and had protective effects with regard to the risk of death. Compared with CRT, HIFU ＋LRT significantly decreased incidences of radiation-related late gastrointestinal （GI） and genitourinary （GU） toxicity grade ≥ II. In conclusion, long-term survival of patients with advanced PCa benefited from strengthening local control of primary tumour and reRional lymph node metastases after HT. As an alternative to CRT, HIFU＋LRT showed Rood efficacy and better safety.

High-intensity focused ultrasound ablation as a bridging therapy for hepatocellular carcinoma patients awaiting liver transplantation

The scarcity of liver grafts in Asia leads to a significant dropout of patients from liver transplant waiting lists, particularly patients with hepatocellular carcinoma and a low model for end-stage liver disease score. In order to reduce dropping out, different bridging therapies are employed. We report the use of high-intensity focused ultrasound ablation as a bridging therapy for a patient with hepatocellular carcinoma of stage two and an extremely low platelet count (20×10 9 /L). The ablation was successful. Blood tests showed that his liver function was similar before and after the treatment. No adhesion was encountered in the liver transplantation performed six months later.

The Effects of Laser Therapy in Treating Hypertrophic Scars and Keloids after Median Sternotomy:A Scoping Review

Background:Hypertrophic scars and keloids,common complications following median sternotomy for cardiac surgery,significantly impact patient quality of life due to their aesthetic and symptomatic burden.Recent advancements in laser therapy have made it a prominent option for managing these complex scars,yet a com-prehensive understanding of its efficacy is lacking.The aim of this scoping review is to explore the effects of laser therapy in managing hypertrophic scars and keloids after median sternotomy.Methods:This scoping review ana-lyzed studies up to February 2024 from databases including PubMed,EMBASE,CINAHL,Scopus,Web of Science,and the Cochrane Library.We included any study that assessed laser therapy’s effects on hypertrophic scars and keloids following median sternotomy.Studies were selected based on predefined inclusion criteria with-out publication year,design,or origin restrictions.Results:Six studies met the inclusion criteria,involving a total offive RCTs and one review.These studies primarily tested 585 and 595-nm pulsed dye laser(PDL)treatments,focusing on scar appearance,patient symptoms,and treatment satisfaction.Most studies reported significant improvements in scar height reduction and patient symptom relief after treatment,with mixed results for scar erythema and elasticity.Adverse events were generally mild and transient.Conclusions:Laser therapy offers a beneficial approach for improving the appearance and symptoms of hypertrophic scars and keloids post-median sternotomy.However,further research is necessary to optimize treatment parameters and explore the long-term psychosocial impacts of this therapy.This review highlights the need for more comprehensive studies to establish standardized treatment protocols and evaluate their effectiveness.

Treatable focal region modulated by double excitation signal superimposition to realize platform temperature distribution during transcranial brain tumor therapy with high-intensity focused ultrasound

Recently, the phase compensation technique has allowed the ultrasound to propagate through the skull and focus into the brain. However, the temperature evolution during treatment is hard to control to achieve effective treatment and avoid over-high temperature. Proposed in this paper is a method to modulate the temperature distribution in the focal region. It superimposes two signals which focus on two preset different targets with a certain distance. Then the temperature distribution is modulated by changing triggering time delay and amplitudes of the two signals. The simulation model is established based on an 82-element transducer and computed tomography （CT） data of a volunteer＇s head. A finite- difference time-domain （FDTD） method is used to calculate the temperature distributions. The results show that when the distances between the two targets respectively are 7.5-12.5 mm on the acoustic axis and 2.0-3.0 mm in the direction perpendicular to the acoustic axis, a focal region with a uniform temperature distribution （64-65 ℃） can be created. Moreover, the volume of the focal region formed by one irradiation can be adjusted （26.8-266.7 mm3） along with the uniform temperature distribution. This method may ensure the safety and efficacy of HIFU brain tumor therapy.

Effect of Intrauterine Laser Therapy at the IVF Success Rate on Infertile Patients with a History of IVF Failure: A Pilot Non-Blinded Study

Backgrounds: While there’s developing proof aimed toward improving embryo implantation thru a focal point on great development, restrained studies have been performed on enhancing endometrial receptivity. Intrauterine Laser Therapy (LT) can be powerful in selling endometrial cell proliferation, therefore enhancing the achievement of assisted reproductive techniques (ART). The contemporary look at aimed to research the effectiveness of effective intrauterine lasers in growing endometrial thickness and the achievement of being pregnant rate. Materials and Methods: In the current clinical randomized trial (RTC) study, the infertile women (20 - 42 years old) referred to the infertility clinic in 2023-2024 who were candidates for IVF treatment with recurrent implantation failure (RIF) history were included. The patients were divided into two main groups: the intervention group;low level laser therapy (LLLT) after hormone administration) (n = 52) and the control group (hormone administration without LT) (n = 52). The IVF success rate and change in endometrial thickness before and after the LT were compared in groups. Results: There was a significant difference between groups (p Conclusion: It appears that the incorporation of Intrauterine LT in the realm of infertility could significantly impact as a novel supplementary treatment in improving endometrial receptivity and pregnancy rate.

Salvage Transrectal High-Intensity Focused Ultrasound Therapy for Patients with Recurrence of Vesico-Urethral Anastomosis after Radical Prostatectomy

Background: Salvage radiotherapy has been used as the treatment for patients with local recurrence after radical prostatectomy. However, the therapy is time-consuming and it experiences adverse effects of some kind. Simple and less invasive treatment is highly anticipated. Objectives: To evaluate the outcomes of salvage transrectal high-intensity focused ultrasound (HIFU) therapy for patients with localized recurrence of a vesicourethral anastomosis (VUA) after radical prostatectomy. Material and methods: Sixteen patients with suspected local recurrence of a VUA after prostatectomy were treated with HIFU. All patients had prostate-specific antigen (PSA) failure (>0.2 ng/ml), positive findings of a VUA with biopsy and/or MRI, TRUS and CT, and no distant metastasis by CT, MRI and bone scintigraphy before HIFU. Recurrence after HIFU was determined by PSA failure (>0.2 ng/ml), histological findings, metastasis and start of systemic therapies. Results: HIFU treatments were performed in 16 patients, and followed-up for 7 - 159 months (median 46.5). The pre-HIFU PSA levels ranged from 0.318 to 3.1 ng/ml. Sonication time ranged from 9 - 42 min. All patients had a decline of PSA after HIFU, and 88% of the PSA nadir was Conclusion: HIFU therapy for local recurrence after prostatectomy may become a feasible salvage therapeutic option because of its ease and simple procedure. For salvage HIFU therapy, further research and additional follow-up are required to evaluate and correct the diagnosis of recurrence areas and to provide the sufficient sonication.

High-intensity focused ultrasound treatment for patients with unresectable pancreatic cancer

BACKGROUND: High-intensity focused ultrasound (HIFU) is a non-invasive method of solid tissue ablation therapy. However, only a few studies have reported the effect of HIFU for unresectable pancreatic cancer. This study aimed to evaluate the clinical benefits, survival time and complications associated with the use of HIFU ablation in patients with unresectable pancreatic cancer. METHODS: Twenty-five patients with unresectable pancreatic cancer were enrolled in our study. All patients received HIFU therapy for tumors at least once. The therapeutic effects of HIFU was evaluated in terms of Karnofsky performance status (KPS) scores, pain relief, serum CA19-9, and imaging by B-US and CT before and after the therapy. We also recorded median overall survival time and complications caused by the treatment. RESULTS: In the 25 patients, KPS scores were above 60, and increased KPS was observed in 23 patients after treatment. Pain relief occurred in 23 patients. Serum CA19-9 levels were significantly reduced one month after HIFU treatment and became negative in 5 patients. B-US revealed enhanced tumor echogenicity in 13 patients and decreased tumor blood supply in 9. Tumor necrosis was confirmed by CT in 8 patients one month after HIFU treatment. The median overall survival time was 10 months, and the 1-year survival rate was 42%. No severe complications were observed after HIFU treatment. CONCLUSION: HIFU can effectively relieve pain, increase KPS, decrease tumor growth and prolong the survival time of patients with unresectable pancreatic cancer.

Deep-Tissue Photothermal Therapy Using Laser Illumination at NIR-Ⅱa Window

Photothermal therapy(PTT)using near-infrared(NIR)light for tumor treatment has triggered extensive attentions because of its advantages of noninvasion and convenience.The current research on PTT usually uses lasers in the first NIR window(NIR-I;700–900 nm)as irradiation source.However,the second NIR window(NIR-II;1000–1700 nm)especially NIRIIa window(1300–1400 nm)is considered much more promising in diagnosis and treatment as its superiority in penetration depth and maximum permissible exposure over NIR-I window.Hereby,we propose the use of laser excitation at 1275 nm,which is approved by Food and Drug Administration for physical therapy,as an attractive technique for PTT to balance of tissue absorption and scattering with water absorption.Specifically,CuS-PEG nanoparticles with similar absorption values at 1275 and 808 nm,a conventional NIR-I window for PTT,were synthesized as PTT agents and a comparison platform,to explore the potential of 1275 and 808 nm lasers for PTT,especially in deep-tissue settings.The results showed that 1275 nm laser was practicable in PTT.It exhibited much more desirable outcomes in cell ablation in vitro and deep-tissue antitumor capabilities in vivo compared to that of 808 nm laser.NIR-IIa laser illumination is superior to NIR-I laser for deep-tissue PTT,and shows high potential to improve the PTT outcome.

Experimental Study on the Effect of High-intensity Focused Ultrasound (HIFU) Using Sonablate-500 in the Ablation of Canine Prostate

To investigate the safety, feasibility and effectiveness of transrectal high-intensity focused ultrasound （HIFU） in the ablation of canine prostate, 20 dogs were divided randomly into 5 groups. Sixteen canine prostates were treated with the third-generation transrectal HIFU device （Sonablate-500^TM）. Transrectal ultrasound images of the prostate and prostatic urethra were observed preoperatively and postoperatively. Serial study was performed 30 min, 30 days, 60 days and 180 days after the therapy. The rectum, periprostatic tissues, and prostate were excised en bloc and the tissues were fixed for gross and histological analysis. Our results showed that the average maximal diameter of prostatic urethra was 0.59-0.11 cm before the operation and 2.57±0.98 cm 60 days after the operation. The volume of prostate was 6.5±3.12 cm^3 before the treatment while the volume was 4.13±0.23 cm^3 60 days after the treatment and the differences were statistically significant （P〈0.05）. Histologically, there was a clear demarcation between the necrotic area of the treated tissues and the unaffected surrounding tissues. All the necrotic tissues in the targeted zone broke off and the prostatic urethra became cavitary 60 days later. The more frequent complications were urinary retention and frequency and hematuria. No rectal injury occurred during the treatment. It is concluded that the third-generation transrectal HIFU is capable of destroying prostatic tissue, substantially increasing the width of the prostatic urethra without causing injury to the adjacent tissues. The risk of postoperative complications associated with HIFU was low. HIFU may become a safe, effective and minimally invasive alternative for the treatment of prostatic diseases.

Effect of low-level laser therapy on tooth-related pain and somatosensory function evoked by orthodontic treatment

Low-level laser therapy(LLLT) may have an effect on the pain associated with orthodontic treatment. The aim of this study was to evaluate the effect of LLLT on pain and somatosensory sensitization induced by orthodontic treatment. Forty individuals(12–33 years old; mean ± standard deviations: 20.8 ± 5.9 years) scheduled to receive orthodontic treatment were randomly divided into a laser group(LG) or a placebo group(PG)(1:1). The LG received LLLT(810-nm gallium-aluminium-arsenic diode laser in continuous mode with the power set at 400 mW, 2 J·cm–2) at 0 h, 2 h, 24 h, 4 d, and 7 d after treatment, and the PG received inactive treatment at the same time points. In both groups, the non-treated side served as a control. A numerical rating scale(NRS) of pain, pressure pain thresholds(PPTs), cold detection thresholds(CDTs), warmth detection thresholds(WDTs), cold pain thresholds(CPTs), and heat pain thresholds(HPTs) were tested on both sides at the gingiva and canine tooth and on the hand. The data were analysed by a repeated measures analysis of variance(ANOVA). The NRS pain scores were significantly lower in the LG group(P = 0.01). The CDTs,CPTs, WDTs, HPTs, and PPTs at the gingiva and the PPTs at the canine tooth were significantly less sensitive on the treatment side of the LG compared with that of the PG(P < 0.033). The parameters tested also showed significantly less sensitivity on the nontreatment side of the LG compared to that of the PG(P < 0.043). There were no differences between the groups for any quantitative sensory testing(QST) measures of the hand. The application of LLLT appears to reduce the pain and sensitivity of the tooth and gingiva associated with orthodontic treatment and may have contralateral effects within the trigeminal system but no generalized QST effects. Thus, the present study indicated a significant analgesia effect of LLLT application during orthodontic treatment.Further clinical applications are suggested.

Efficacy of super-pulsed 905 nm Low Level Laser Therapy (LLLT) in the management of Traumatic Brain Injury (TBI): A case study

Traumatic brain injury is a major health concern worldwide with massive financial and social impact. Conventional treatments primarily focus on the prevention of further damage to the brain parenchyma, while failing to address the already existent symptoms. Previous clinical studies have shown that Low Level Laser Therapy (LLLT) can significantly reduce pain and induce temporary vasodilation in capillaries, which the authors hypothesize can be used to improve the quality of life in TBI patients by treating their current symptoms, which are predominately migraine-like headaches. This case report illustrates the use of LLLT in the treatment of a patient with a TBI and the great clinical success achieved in the reduction of pain, as measured by VAS—achievable within five treatments of 10 minutes in duration.

Low-level laser therapy enhances the number of osteocytes in calvaria bone defects of ovariectomized rats

Background : Osteoporosis can make bone repair difficult. Low-level laser therapy( LLLT) has been shown to be a promising tool for bone neoformation. This study aimed to analyze the effect of LLLT on calvaria bone defects of ovariectomized rats using stereology. Methods : Fifty-four Wistar rats were subjected to bilateral ovariectomy, and bone defects were created in calvaria after 150 days. The animals were divided into nine groups(n = ?6 per group), and 24 hours after the bone defects were created they received three, six or 12 sessions of LLLT at 0, 20 or 30 J/cm 2, using a 780-nm low-intensity GaAlAs laser. One-way ANOVA followed by Tukey ' s post hoc test was used for data processing. A difference of P < 0.05 was considered statistically significant. The parameters evaluated were osteocyte density( Nv_(ost)), total osteocyte number( Nto ost), trabecular surface density( Sv_t), and trabecular surface area( Sa_t). Results : Data obtained showed that Nto ost, Sv t, and Sa t in group G2 rats were significantly different from G1(0 J/cm^2)( P < 0.05). Compared to group G4, G5 presented higher values for the parameters Sv t and Sa t, and G6 presented significantly higher values for almost all the analyzed parameters( Nv _(ost), Nto_(ost), Sv_t, and Sa t)( P < 0.05). Compared to group G7, G8 showed a higher value only for the parameter Sa t, and G9 showed significantly higher values for parameters Nv ost, Nto ost, Sv_t, and Sa_t. Conclusion : We conclude that LLLT stimulated bone neoformation and contributed to an increase in the total number of osteocytes, especially with a laser energy density of 30 J/cm^2 given for six and 12 sessions.

Treatment effects and periodontal status of chronic periodontitis after routine Er:YAG laser-assisted therapy

BACKGROUND Routine preclinical interventions for patients with chronic periodontitis such as supragingival cleaning and subgingival curettage,establishing a balanced occlusal relationship,and irrigation with 3%hydrogen peroxide can relieve the symptoms to some extent.However,there is room for improvement in the overall effect.For example,Er:YAG lasers can quickly increase the temperature of the irradiated tissue,effectively eliminate dental plaque and calculus,reduce periodontal pockets,adjust periodontal microecology,and reduce the gingival sulcus.The content of factors in the liquid,and then achieve the purpose of treatment.AIM The aim was evaluate the effect of Er:YAG laser-assisted routine therapy on the periodontal status in chronic periodontitis.METHODS Between October 2018 and January 2020,106 patients with chronic periodontitis in our hospital were randomly assigned to either the study or control group,with 53 patients in each group.The control group underwent routine therapy,and the study group underwent Er:YAG laser therapy in addition to routine therapy.We evaluated the treatment outcome in both groups.Periodontal status was determined by clinical attachment loss(CAL),gingival index(GI),periodontal probing depth(PD),dental plaque index(PLI),and sulcular bleeding index(SBI),inflammatory factors in the gingival crevicular fluid,tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),IL-8],and colony forming units(CFUs).RESULTS Total effectiveness in the study group(94.34%)was higher than that in the control group(79.25%,P<0.05).The clinical parameters in the study group(PD,5.28±1.08 mm;CAL,4.81±0.79 mm;SBI,3.37±0.59;GI,1.38±0.40;PLI,2.05±0.65)were not significantly different from those in the control group(PD,5.51±1.14 mm;CAL,5.09±0.83 mm;SBI,3.51±0.62;GI,(1.41±0.37;PLI,1.98±0.70)before treatment(P>0.05).However,after treatment,the parameters in the study group(PD,2.97±0.38 mm;CAL,2.71±0.64 mm;SBI,2.07±0.32;GI,0.51±0.11;PLI,1.29±0.34)were lower than those in the control group(PD,3.71±0.42 mm;CAL,3.60±0.71 mm;SBI,2.80±0.44;GI,0.78±0.23;PLI,1.70±0.51)(P<0.05).Differences in crevicular TNF-α,IL-6,and IL-8 levels in the study(TNF-α,7.82±3.43 ng/mL;IL-6,11.67±2.59 ng/mL;IL-8,12.12±3.19 pg/mL)and control groups(TNF-α,9.06±3.89 ng/ml,IL-6,12.13±2.97 ng/mL,IL-8,10.99±3.30 pg/mL)before therapy(P>0.05)were not significant.Following treatment,the parameters were significantly lower in the study group(TNF-α,2.04±0.89 ng/mL;IL-6,4.60±1.26 ng/mL;IL-8,3.15±1.08 pg/mL)than in the control group(TNF-α,3.11±1.07 ng/mL;IL-6,6.25±1.41 ng/mL;IL-8,4.64±1.23 pg/mL,P<0.05).The difference in the CFU of the study group[(367.91±74.32)×104/mL and control group(371.09±80.25)×104/mL]before therapy was not significant(P>0.05).The CFU decreased in both groups following therapy,however,the CFU values were lower in the study group[(36.09±15.26)×104/mL]than in the control group[(45.89±18.08)×104/mL](P<0.05).CONCLUSION Combining Er:YAG lasers with routine measures significantly improved the overall periodontal therapy outcomes by improving periodontal status and reducing oral levels of inflammatory factors and CFUs.

Effect of low level laser therapy on dental pulp during orthodontic movement

AIM: To validate the protocol described here to be used in future clinical trials related to the effect of laser therapy on dental pulp. METHODS: Histologically treated samples from eight human healthy premolar teeth obtained from the middle root level were distributed in four groups: group 1(G1) absolute control; group 2(G2) only laser irradiation; group 3(G3) exposed only to orthodontics; and group 4(G4) treated with orthodontics and laser. Laser treatment was performed at 830 nm wavelength, 100 mW(energy 80 J/cm2, 2.2 J), for 22 s in the vestibular surface and 22 s in the palatal surface, 1 mm away from the dental root mucosa. Three staining methods were performed: hematoxylin-eosin(HE), Masson's Trichrome method and Gomori's method.RESULTS: The pulp histology parameters were evaluated and the results classified in to 3 parts: an inflammatory response, soft tissue response(dental pulp) and hard tissue response(dentin and predentin). There was no inflammation(chronic or acute) in any of the evaluated groups. The zones of pulp necrosis were found in one premolar of G3 and in one of G4; in groups G2 and G4 there was higher angiogenesis than in the other two groups. G4 group presented the highest level of vascularization. A reduced nerve density was observed in G3. A G2 specimen showed increased nerve density. A higher rate of calcification was observed in G1 compared to G2. Denticles, either real or false, were observed in G1, G2 and G3. Sclerosis of dentin and focal dentin loss was observed among all the groups. Secondary dentin was present in one sample in G1 and G2. A necrosis zone was found in one sample of G3 and G4. No differences between groups were observed in the odontoblast irregularity layer but the layer was wider in the group treated with laser only. A notable difference was detected in reduction of the cell-free layer between the groups G1 and G4. The findings in pulp tissue favor its adaptative response against dental movement induced by orthodontics. No definitive conclusions may be derived as this is a pilot study. CONCLUSION: The protocol described here was shown to be an effective method to evaluate changes in dental pulp submitted to low level laser in teeth under orthodontic movement.

Neuroimmunomodulatory effects of transcranial laser therapy combined with intravenous tPA administration for acute cerebral ischemic injury

At present, the only FDA approved treatment for ischemic strokes is intravenous administration of tissue plasminogen activator within 4.5 hours of stroke onset. Owing to this brief window only a small percentage of patients receive tissue plasminogen activator. Transcranial laser therapy has been shown to be effective in animal models of acute ischemic stroke, resulting in significant improvement in neurological score and function. NEST-1 and NEST-2 clinical trials in human patients have demonstrated the safety and positive trends in efficacy of transcranial laser therapy for the treatment of ischemic stroke when initiated close to the time of stroke onset. Combining intravenous tissue plasminogen activator treatment with transcranial laser therapy may provide better functional outcomes. Statins given within 4 weeks of stroke onset improve stroke outcomes at 90 days compared to patients not given statins, and giving statins following transcranial laser therapy may provide an effective treatment for patients not able to be given tissue plasminogen activator due to time constraints.

Variable spot size optical system for a dual-wavelength laser therapy device

The majority of existing high-power laser therapeutic instruments employ a single wavelength for a single target;thus,they do not meet the requirements for clinical treatment.Therefore,this study designs an optical system for a dual-wavelength high-power laser therapeutic device with a variable spot size.The waist of the short arm of the optical cavity and the G1G2 parameter(G-parameter equivalent cavity method)is calculated using MATLAB software,the spot size and divergence angle on the lens are calculated using an ABCD matrix,and the distance between the treatment spot at different spot sizes and the transformation lens is calculated in order to design the treatment handpiece.Experiments are conducted to analyze the stability at an output power of 532 nm before beam combination and the power loss after beam combination.The results show that the output power stability of the 532-nm beam varies by less than 2%over 150 min,and the loss of both wavelengths is less than 20%,which meets the clinical requirements of the system.The safety performance can meet the requirements of national general standards for medical electrical safety.The proposed dual-wavelength laser therapy instrument has both visible wave and near-infrared wave characteristics;thus,it can accurately target both superficial vessels and vessels with a larger diameter and deeper position.This therapeutic device has the advantages of simple operation,stable and reliable laser output,high security and strong anti-interference ability,and meets the comprehensive clinical treat-ment demands of vascular diseases.

Liver-directed therapies for liver metastases from neuroendocrine neoplasms:Can laser ablation play any role?

Aggressive cytoreduction can prolong survival in patients with unresectable liver metastases(LM)from neuroendocrine neoplasms(NEN),and minimally invasive,liver-directed therapies are gaining increasing interest.Catheter-based treatments are used in disseminated disease,whereas ablation techniques are usually indicated when the number of LM is limited.Although radiofrequency ablation(RFA)is by far the most used ablative technique,the goal of this opinion review is to explore the potential role of laser ablation(LA)in the treatment of LM from NEN.LA uses thinner needles than RFA,and this is an advantage when the tumors are in at-risk locations.Moreover,the multi-fiber technique enables the use of one to four laser fibers at once,and each fiber provides an almost spherical thermal lesion of 12-15 mm in diameter.Such a characteristic enables to tailor the size of each thermal lesion to the size of each tumor,sparing the liver parenchyma more than any other liver-directed therapy,and allowing for repeated treatments with low risk of liver failure.A recent retrospective study reporting the largest series of LM treated with LA documents both safety and effectiveness of LA,that can play a useful role in the multimodality approach to LM from NEN.

Induction of Autologous Bone-Marrow Stem Cells by Low-Level Laser Therapy Has Beneficial Effects on the Kidneys Post-Ischemia-Reperfusion Injury in the Rat

Acute renal failure has a 50% - 80% mortality rate. Currently, treatment options for this life-threatening disease are limited. Low-level laser therapy (LLLT) has been found to modulate biological activity. The aim of the present study was to investigate the possible beneficial effects of laser application to stem cells in the bone marrow, on the kidneys of rats that had undergone ischemia-reperfusion injury (IRI). IRI was induced by occlusion of the renal artery to 3- and 7-month-old rats for 15 or 30 minutes. In an additional experiment IRI was applied to both kidneys for 20 min each in 2-3-month-old rats. Rats were then divided randomly into two groups of control and laser-treated. Laser therapy (Ga-Al-As 810 nm, 200 mW output for 2 min) was applied to the bone marrow 1 and 7 days post-IRI to the kidneys, and rats were sacrificed 2 weeks later. Histomorphometry and immunohistochemistry were performed on kidney sections and blood markers for kidney function. Quantitative histomorphometric analysis revealed a reduction in dilatation of the renal tubules, restored structural integrity of the renal tubules, and reduced necrosis in the laser-treated rats as compared to the control, non-laser-irradiated group. C-kit positive cell density in kidneys post-IRI and laser-treatment was significantly (p = 0.015) 3.2-fold higher compared to the control group. Creatinine and blood urea nitrogen content were significantly lower in the laser-treated rats as compared to control. It is concluded that LLLT application to the bone marrow (BM) causes a significant increase in the density of mesenchymal stem cells in the kidneys post-IRI, probably by induction of stem cells in the BM, which subsequently migrate to the IRI kidney, significantly reducing the pathological features of the kidney and increasing kidney function post IRI.

Laser therapy versus intravitreal injection of anti-VEGF agents in monotherapy of ROP:a Meta-analysis

AIM:To compare the efficacy and safety between laser therapy and anti-vascular endothelial growth factor(VEGF)agents intravitreal injection monotherapy in type-1 retinopathy of prematurity(ROP)and aggressive posterior retinopathy of prematurity(APROP).METHODS:A systematic literature search was performed in PubMed,Cochrane Library,and Embase for original comparable studies.We included studies that compare laser therapy and intravitreal injections of anti-VEGF agents monotherapy in ROP regardless of languages and publication types.RESULTS:Complication incidence was significantly higher in laser therapy group(OR:0.38;95%CI:0.19-0.75;P=0.005).Spherical equivalent(SE)was higher in laser therapy[weighted mean difference(WMD):2.40,95%CI:0.88-3.93;P=0.002].The time between treatment and retreatment was longer in laser therapy group(WMD:8.45,95%CI:5.35-11.55;P<0.00001).Recurrence incidence(OR:0.97;95%CI:0.45-2.09;P=0.93)and retreatment incidence(OR:1.24;95%CI:0.56-2.73;P=0.59)were similar in two approaches.Subgroup analysis between type-1 ROP and APROP was not significant except SE reported in the included studies(P<0.0001).CONCLUSION:This Meta-analysis outcome indicates anti-VEGF agents are as effective as laser treatment,and safer than laser in type-1 ROP and APROP.The degree of myopia in APROP is higher than type-1 ROP.More randomized controlled trials in large sample size should be conducted in the future.