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It was for a long time believed that lidar systems based on the use of high-repetition micro-pulse lasers could be effectively used to only stimulate atmospheric elastic backscatter echoes, and thus were only exploited in elastic backscatter lidar systems. Their application to stimulate rotational and roto-vibrational Raman echoes, and consequently, their exploitation in atmospheric thermodynamic profiling, was considered not feasible based on the technical specifications possessed by these laser sources until a few years ago. However, recent technological advances in the design and development of micro-pulse lasers, presently achieving high UV average powers (1-5 W) and small divergences (0.3-0.5 mrad), in combination with the use of large aperture telescopes (0.3-0.4 m diameter primary mirrors), allow one to presently develop micro-pulse laser-based Raman lidars capable of measuring the vertical profiles of atmospheric thermodynamic parameters, namely water vapor and temperature, both in the daytime and night-time. This paper is aimed at demonstrating the feasibility of these measurements and at illustrating and discussing the high achievable performance level, with a specific focus on water vapor profile measurements. The technical solutions identified in the design of the lidar system and their technological implementation within the experimental setup of the lidar prototype are also carefully illustrated and discussed.
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PURPOSE: To evaluate the efficacy of subthreshold micropulse laser (SML) treatment for chronic central serous chorioretinopathy (CSC). METHODS: PubMed, Cochrane Library, and Embase were comprehensively searched for studies published up to April 19, 2021. Randomized controlled trials (RCTs), retrospective and prospective cohort studies that compared SML with any other intervention for chronic CSC were selected. The primary outcomes were best corrected visual acuity (BCVA) and central macular thickness (CMT). Meta-analysis was performed using Review Manager 5.3. Random-effect model was used for pooled analysis. RESULTS: Eleven studies including 834 eyes were included, with 428 eyes undergoing SML treatment and 406 eyes receiving other interventions. Pooled results showed no significant differences between SML and control with respect to BCVA, CMT, or complete resolution of subretinal fluid, while SML treatment was inferior to control in terms of subfoveal choroidal thickness (SFCT) reduction [weighted mean difference (WMD)=44.75, 95% Cl, 14.31-75.20, P<0.05, I2=72%]. However, SML was not superior to photodynamic therapy with respect to SFCT (WMD=61.29, 95% Cl, 29.50-93.08, P<0.05, I2=56%), retinal sensitivity (WMD=-1.85, 95% Cl, -3.05--0.65, P<0.01, I2=0) or NEI-VFQ25 score (WMD=-2.44, 95% Cl, -4.72--0.16, P<0.05, I2=0). No serious side effects of SML treatment were observed. CONCLUSION: Available evidence suggests that the clinical efficacy of SML therapy is similar to other treatment modalities for chronic CSC. However, because of the lack of serious side effects, SML may be the most promising alternative therapy for chronic CSC. The study protocol was registered on PROSPERO (CRD42021 258837).
Subject(s)
Central Serous Chorioretinopathy , Photochemotherapy , Central Serous Chorioretinopathy/drug therapy , Central Serous Chorioretinopathy/surgery , Choroid , Chronic Disease , Fluorescein Angiography , Humans , Lasers , Photochemotherapy/methods , Retrospective Studies , Tomography, Optical Coherence , Treatment Outcome , Visual AcuityABSTRACT
@#AIM: To appraise the therapeutic effect of dual laser(micro-pulse laser and traditional laser)and single intravitreal injection with conberceptin on macular edema secondary to ischemic branch retinal vein occlusion.<p>METHODS: A prospective cohort study was conducted. 83 patients(83 eyes)participated in the study from November 2017 to November 2018. They were randomly divided into two groups. Group A(42 eyes)accepted the treatment of dual laser and single intravitreal injection with conbercept and group B(41 eyes)accepted only traditional laser treatment and single intravitreal injection with anti-VEGF, and the aim is to analysis the data including BCVA, CMT in follow-up visit after treatment 1, 3, 6mo.<p>RESULTS: After 1mo: in group A, BCVA improved from 0.88±0.11 to 0.43±0.19(<i>P</i><0.01), CMT changed from 595.00±61.12 to 379.8±76.08μm(<i>P</i><0.01). In group B, BCVA changed from 0.82±0.19 to 0.39±0.16(<i>P</i><0.01)while CMT changed from 601.70±81.37 to 381.50±70.92 μm(<i>P</i><0.01). There were no difference between two groups(<i>P</i>>0.05). After 3mo: in group A, BCVA raised to 0.13±0.07(<i>P</i><0.01), CMT reduced to 282.80±31.93μm(<i>P</i><0.01); in group B, BCVA hold on 0.41±0.09(<i>P</i>=1.00), CMT retained 395.80±34.53μm(<i>P</i>=0.99). The improvement of BCVA and CMT were better in group A(<i>P</i><0.01). After 6mo: in group A, BCVA maintained 0.28±0.12(<i>P</i><0.01), CMT keeped 335.60±33.98μm(<i>P</i>=0.02); in group B, BCVA rebounded to 0.77±0.15(<i>P</i><0.01), CMT was 579.60±19.61μm(<i>P</i><0.01). Both BCVA and CMT were better in group A than group B(<i>P</i><0.01). No serious complications happened in all phases.<p>CONCLUSION: The treatment of dual laser and single intravitreal injection with conbercept for macular edema secondary to ischemic branch retinal vein occlusion can maintain good effect more than 3mo.
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@#AIM: To explore the clinical effect of micro-pulse laser at 577nm threshold in treatment of diabetic macular edema(DME).<p>METHODS: The clinical data of 48 patients with DME(64 eyes)were retrospectively analyzed. The patients with micro-pulse laser at 577nm threshold were included in observation group(26 cases, 35 eyes), and the patients who underwent conventional grid-like laser were included in control group(22 cases, 29 eyes). The best corrected visual acuity(BCVA)(LogMAR visual acuity chart), central macular foveal thickness(CFT), mean tetinal sensitive(MS)and mean visual deviation(MD)were compared before surgery and at 1, 3 and 6mo after surgery. And duration of fundus hard exudate and the occurrence of complications after surgery were analyzed in the two groups.<p>RESULTS: At 1, 3 and 6mo after surgery, the LogMAR visual acuity test results and CFT levels in the two groups were significantly decreased compared with those before surgery, and the indexes in observation group were significantly lower than those in control group at the same time(0.30±0.09 <i>vs</i> 0.35±0.10, 0.19±0.07 <i>vs</i> 0.26±0.09, 0.13±0.04 <i>vs</i> 0.18±0.05; 349.26±21.80 μm <i>vs</i> 364.37±23.91μm, 314.46±20.49μm <i>vs</i> 335.07±22.68μm, 328.35±21.74μm <i>vs</i> 352.43±23.60μm)(all <i>P</i><0.05). Compared with preoperative, the MS and MD levels in observation group were significantly increased, and significantly higher than that in control group at the same time(5.83±1.16dB <i>vs</i> 4.22±1.04dB, 6.38±1.29dB <i>vs</i> 4.49±1.17dB, 6.75±1.22dB <i>vs</i> 4.68±1.20dB, -5.53±1.41dB <i>vs</i> -7.66±1.52dB, -5.09±1.30dB <i>vs</i> -7.26±1.39dB, -4.68±1.14dB <i>vs</i> -7.05±1.26dB)(all <i>P</i><0.05). The duration of fundus hard exudate in observation group was significantly lower than that in control group(3.39±0.80mo <i>vs</i> 4.25±1.14mo)(<i>P</i><0.05). Within 6mo after surgery, the incidence rate of eyeball pain in observation group was significantly lower than that in control group \〖3%(1/35)<i>vs</i> 24%(7/29)\〗(<i>P</i><0.05), but there were no statistically significant differences in the incidence rates of anterior chamber inflammatory response, visual field defect, intraocular hypertension and corneal edema.<p>CONCLUSION: Micro-pulse laser at 577nm threshold is safe and effective for DME.
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Objective To discuss the relationship between diabetic macular edema(DME) and visual field defects and evaluatethe therapeutic effect of micro-pulse laser.Methods A total of 117 patients (149 eyes) with diabetic retinopathy(DR) were enrolled in this study and divided into two groups according to early treatment diabetic retinopathy study(ETDRS) DME diagnostic criteria:DME group(n=50,70 eyes) and N-DME group(n=67,79 eyes).Healthy subjects(n=40,80 eyes)were selected as NC group in thisstudy.The clinical data and biochemical index were collectedand visual fields were examined in all the subjects.Then the DME group was further divided into two subgroups:micro-pulse laser subgroup(35 eyes) and conventional laser subgroup(35 eyes).The vision recovery after treatment was evaluated on different time points.Results Diabetes duration,FPG,HbA1c and HOMA-IR were significantly higher in DME group than in N-DME group (P0.05).Multiple logistic regression analysis showed that DM duration,FPG,HbA1c and HOMA-IR were riskfactors for DME(all P<0.01).Conclusion Patients with DME have severe vision loss.Micro-pulse laser therapy is helpful invision recovery,while conventional laser therapy have no obvious effect on it.Longer duration of DM,higher level of FPG,HbA1c,and IR severity may increase the risk of DME.
