Subthreshold Micropulse Laser Research Articles

Sub-Threshold Micro Pulse Laser (810NM): Treatment for Chronic Central Serous Retinopathy

Purpose: To find the effectiveness of sub-threshold (810nm) micropulse diode laser treatment (SMT) in chronic central serous retinopathy (CSR).
 Study Design: Interventional case series.
 Place and Duration of Study: Layton Rahmatulla benevolent trust eye hospital, from April 2019 to July 2020.
 Methods: The patients of chronic CSR (≥ 6 months) participated in the study. We used Spectral Domain Optical coherence tomography (SD-OCT) to record baseline central retinal thickness (CT). Best corrected visual acuity (BCVA) was recorded with Snellen’s chart and converted to Log MAR for statistical analysis. All patients underwent treatment with sub-threshold laser (810nm) in micropulse mode with 5% duty cycle (DC).
 Results: Twenty five eyes with chronic CSR were enrolled in the study. The patients were treated with laser and final assessment was made at 6 months. Mean BCVA at presentation was 0.46 Log MAR ± 0.12 and a mean baseline CT of 362.2 μm ± 32.6µm. At final follow-up there was a mean decrease in CT of 97.2 μm ± 21.8 from the baseline. After treatment mean BCVA was 0.33 Log MAR ± 0.12 and mean CT was 266 μm ± 20.9. Nineteen out of twenty-five eyes (76%) achieved a gain of vision between 1 to 3 lines and gain of 3 lines was achieved in 8% of cases. At the final follow-up there was incomplete resolution of sub retinal fluid in 4 eyes (16%) with no improvement in BCVA.
 Conclusion: SMT (810 nm) is an effective and minimally invasive treatment modality for chronic CSR.
 Key Words: Sub-Threshold micropulse laser, Central serous retinopathy, Central retinal thickness, sub retinal fluid.

Comparison of the efficacy and safety between subthreshold micropulse laser, standard-fluence and low-fluence photodynamic therapy for chronic central serous chorioretinopathy

To compare the efficacy and safety of subthreshold micropulse laser treatment (SML), standard-fluence photodynamic therapy (PDT) and low-fluence PDT in patients with chronic central serous chorioretinopathy (cCSC). This retrospective study included 52 eyes of 46 patients with chronic CSC who were treated with 577nm SML (n=23), standard-fluence PDT (verteporfin 6mg/m2 and light energy 50J/cm2) (n=13), or low-fluence PDT (verteporfin 6mg/m2 and light energy 25J/cm2) (n=16). The mean changes in best-corrected visual acuity (BCVA) and optical coherence tomography (OCT) parameters, including central retinal thickness (CRT), subretinal fluid (SRF) height, and ellipsoid zone (EZ) disruption, over the follow-up period were evaluated. The mean follow-up period was 8.42±3.34 months. In the SML group, the SRF resolution time was longer than the other groups. At 1 month, the SML group's mean CRT was higher than the other groups. The BCVA improvement was statistically significant in all groups (P<0.05), but in the SML group, it was slower than the other groups. Three eyes in the low-fluence and one eye in the standard-fluence PDT group received a second PDT treatment. The mean number of SML treatments was 2.48±1.08. If the EZ was intact, the rate of complete resolution of SRF was higher than if the EZ was disrupted or lost. SML, standard-fluence PDT, and low-fluence PDT can all improve visual acuity in cCSC. Standard-fluence and low-fluence PDT induced a more rapid reabsorption of the fluid, improvement of BCVA, and equal safety compared with SML. More treatment sessions of SML were required than with the other treatment modalities.

Optical coherence tomography parameters as predictors of treatment response to a 577-nm subthreshold micropulse laser in chronic central serous chorioretinopathy.

To determine the relation between retinal microstructural changes and the response to 577-nm subthreshold micropulse laser (SML) treatment in chronic central serous chorioretinopathy (cCSC). This retrospective study included 39 eyes of 39 patients with cCSC, treated with the 577-nm SML. The eyes were evaluated in three groups: complete remission, partial remission, and failure groups. The presence of some baseline retinal microstructural changes, thickness of the outer nuclear layer (ONL), status of the ellipsoid zone (EZ), and retinal pigment epithelium (RPE) were evaluated. The changes in central macular thickness (CMT), subretinal fluid (SRF) height, and best-corrected visual acuity (BCVA) were calculated. There were 14, 13, and 12 eyes in the complete remission, partial remission, and failure group, respectively. The baseline EZ and RPE were found intact in 71.4% and 64.3% of the eyes in the complete remission group, respectively; however, these rates were respectively 25% and 16.7% in the failure group (p < 0.05). Extrafoveal foci were present in 35.7% of the eyes in the complete remission group, but none was found in the failure group (p < 0.05). Although there was no statistically significant difference, the baseline ONL thickness was higher, and the hyperreflective dots, retinal bumps, subretinal fibrinous exudates, and PEDs were seen less in the complete remission group. The changes of the BCVA were not significant in any of the groups at the last visit (p > 0.05). The presence of baseline intact EZ and RPE, and extrafoveal foci can potentially be used as predictors of the SML treatment success in cCSC.

Subthreshold micropulse laser adjuvant to bevacizumab versus bevacizumab monotherapy in treating diabetic macular edema: one- year- follow-up.

Purpose:To compare the therapeutic impact of combining intravitreal injections of bevacizumab (IVB) with micropulse laser (MPL) in central diffuse diabetic macular edema (DME) versus IVB monotherapy during 12 months follow-up.Methods:We conducted a retrospective comparative study of 98 treatment-naive eyes (63 patients) with central diffuse DME. The first group of patients (IVB + MPL group, n = 49) was treated with 3 monthly IVB followed by MPL within 1 week after the third injection. Patients were then followed and treated on a pro re nata (PRN) basis, with MPL retreatment if necessary. The changes in best-corrected visual acuity (BCVA), central macular thickness (CMT), number of IVB injections and MPL sessions were evaluated at 4, 8, and 12 months. A control group of diabetic patients with treatment-naive DME was treated with standard protocol of 3 monthly IVB as monotherapy then followed on a PRN basis (IVB group, n = 49). Statistic comparaison of BCVA, CMT, and IVB number variation was interpreted at 12 months between both groups.Results:In IVB + MPL group, baseline BCVA improvement was not significant at 4 and 8 months (p = 0.90, p = 0.08), and was statistically significant (p = 0.01) at 12 months. Mean CMT significantly decreased at 4, 8, and 12 months (p < 0.01) in IVB + MPL group. The difference in BCVA (p = 0.091) and CMT (p = 0.082) variation at 12 months between both groups was not significant but the number of injections was significantly lower in IVB + MPL group (4.1 ± 1.5 injections) compared to IVB group (7.2 ± 1.3 injections) (p < 0.005).Conclusion:Combining intravitreal injections of bevacizumab and MPL in the treatment of DME is effective and safe. This protocol may decrease the number of IVB and its frequency. It offers the advantage of lasting therapeutic response with fewer recurrences.

Pharmacological and physiotherapeutic methods of treating non-exudative age-related macular degeneration

The non-exudative form of age-related macular degeneration (AMD) is a disease with long-term progression for which effective treatments have not been found. Many studies are being conducted to find effective drugs to prevent the appearance of drusen and increase in RPE atrophy area, which could help avoid this more dangerous form of AMD. The main drugs (nutraceuticals) that are used to treat the dry form of AMD are lutein, zeaxanthin and omega-3 fatty acids. Additionally, treatment may include nanosecond laser therapy for drusen in advanced AMD, panretinal subthreshold micropulse laser exposure for atrophic AMD, as well as microcurrent stimulation. Further research in this area should be aimed at understanding all the pathogenetic mechanisms associated with the development of AMD, and developing new approaches to the treatment of this disease including physiotherapy.

Micropulse Transscleral Cyclophotocoagulation: Our Experience

Introduction Traditionally, ciliary body destruction has been used to treat uncontrolled intraocular pressure (IOP) following maximally tolerable medical therapy. This is due to the large number of complications seen with this procedure. However, recently a new technique of sub-threshold laser or micropulse laser, is able to provide selective destruction of the ciliary body in a controlled manner. This avoids most of the complications seen with other modalities. We have performed a small case descriptive pilot study to assess the effectiveness of micropulse transscleral cyclophotocoagulation (MP-TSCPC) in lowering IOP. Methods This pilot study was conducted on four patients in the age range 55-70-years with intractable glaucoma. Two patients had primary angle closure glaucoma, one-each had steroid-induced glaucoma and neovascular glaucoma. Mean baseline IOP was 32±2.4 mmHg. Mean number of glaucoma medications were 2.5±1.5. All patients underwent 180° MP-TSCPC. Absolute success was defined as IOP&lt;20 mmHg without acetazolamide. Results Following the procedure the patients were followed-up at days 1,7,30 and 90. At the last follow-up of the study, mean IOP was 18.2±1.2 mmHg in all four patients. Mild anterior chamber inflammation was the only complication noted. Mean number of glaucoma medications reduced to 1.5±1.0 following the procedure. Thus, absolute success was achieved in all patients. Conclusion This small pilot study validates other studies which show effectiveness of MP-TSCPC as an efficient and safe procedure to lower IOP. This procedure can be used over a wide variety of cases, though the indications for such procedures are still evolving. More extensive and long-term studies will clarify the position of this procedure in our glaucoma management practices.

Anatomical and functional outcomes of subthreshold micropulse laser versus intravitreal ranibizumab injection in treatment of diabetic macular edema

BackgroundTo compare the therapeutic effects of subthreshold micropulse laser (SML) versus intravitreal injection of ranibizumab in treatment of diabetic macular edema (DME) both anatomically using optical coherence tomography (OCT) and functionally using best corrected visual acuity (BCVA) and multifocal electroretinogram (mfERG).Methodshis study was an interventional prospective randomized comparative study. The study included 120 eyes classified into 3 groups: Group 1 included 40 eyes of 28 patients treated by SML laser, group 2 included 40 eyes of 32 patients treated by intravitreal injection of ranibizumab, and group 3 (control group for mfERG) included 40 eyes of 20 patients with diabetes mellitus (DM) of more than 10 year duration with no signs of diabetic retinopathy (DR). BCVA measurements, OCT and mfERG were done for the cases before and after interference and were followed up for 6 monthsResultsBy the end of the follow up period, BCVA significantly improved by 31% in group 1 vs 93% in group 2 with a statistically highly significant difference between the two groups (p value < 0.001). There was also a significant decrease in central subfield thickness in both groups with more reduction in group 2 compared with group 1 (p value < 0.001). There was a significant improvement in P1 amplitude of mf-ERG in group 2 (p value < 0.002) with no significant improvement in group 1. There was a significant decrease in P1 implicit time in group 2 (p value < 0.001) while there was no significant decrease in group1.ConclusionsIntravitreal injection of ranibizumab is a superior treatment modality for DME compared with SML regarding both anatomical and functional outcomes.Trial registration: This study has been approved by the local ethical committee of faculty of medicine of Minia University and retrospectively registered at the clinical trial gov. with Identifier: NCT04332133.

Correspondence on: Efficacy and safety of subthreshold micropulse laser compared with threshold conventional laser in central serous chorioretinopathy

Correspondence on: Efficacy and safety of subthreshold micropulse laser compared with threshold conventional laser in central serous chorioretinopathy

Short Term Presence of Subretinal Fluid in Central Serous Chorioretinopathy Affects Retinal Thickness and Function.

Background: Acute central serous chorioretinopathy (CSCR), with subretinal fluid (SRF) resolving spontaneously within a few months from disease onset, has been considered as a benign and self-limiting disease for many years. This study sought to discover if a short presence of SRF can result in morphological and functional damage to the retina. Materials and methods: The study included patients treated by subthreshold diode micropulse laser (SDM) application for acute CSCR at the Dobry Wzrok Ophthalmological Clinic between January 2018 and November 2019. Inclusion criteria were: first episode of CSCR; duration of symptoms of two months or less; complete resolution of subretinal fluid (SRF) after a single session of SDM; and a lack of any retinal pathology, previous CSCR episode, significant anisometropia or amblyopia in the collateral eye. Fifteen patients fulfilled the inclusion criteria, including 13 males and two females aged 42.3 ± 9.5 years. The mean duration of symptoms before treatment was 4.7 ± 1.3 weeks on average. Baseline and follow-up examinations were performed in both the affected and collateral eyes and included best-corrected visual acuity (BCVA); spectral-domain optical coherent tomography measurements such as central retinal thickness (CRT) and minimal foveal thickness (MFT) (at the follow-up visit only); fluorescein angiography (at presentation only) and fundus autofluorescence. The first follow-up visit, when the total resolution of SRF was noted, was conducted between 8 and 12 weeks after SDM. Results: Resolved CSCR eyes had significantly poorer BCVA, CRT, and MFT findings in comparison with healthy collateral eyes (respectively, 0.11 +/− 0.1 vs. 0.01 +/− 0.04 logMAR; 238.80 +/− 23.39 vs. 264.87 +/− 21.22 µm and 178.93 +/− 16.88 vs. 199.47 +/− 17.87 µm) despite the short period of CSCR duration (maximum of 14 ± 2.15 weeks on average). Conclusion: Short presence of SRF typical for acute CSCR can affect retinal function and morphology resulting in poorer visual outcome.

Subthreshold micropulse laser versus intravitreal anti-VEGF for diabetic macular edema patients with relatively better visual acuity.

To compare the effects of yellow (577 nm) subthreshold micropulse laser (SML) and intravitreal (IV) anti-vascular endothelial growth factor (VEGF) treatment in patients with diabetic macular edema (DME) with relatively better visual acuity [best corrected visual acuity (BCVA) ≤0.15 logMAR]. The medical records of 76 eyes of 47 patients underwent IV (0.5 mg) anti-VEGF injection or SML for the DME with relatively better BCVA were reviewed. The IV group received three consecutive monthly IV anti-VEGF injections, then were retreated as needed. The laser treatment group was treated at baseline and 3mo, and then retreated at 6 and 9mo if needed. All participants were followed up for one year. The mean BCVA and mean central macular thickness (CMT) values changes over the follow-up were evaluated. Twenty-four and 23 patients were assigned to the SML and IV subgroups, respectively. The mean number of treatments was 3.64±0.76 in SML group and 5.85±1.38 in IV group (P<0.05). The subgroups were similar with regard to the mean BCVA score at baseline and at the 1st and 3rd months, but the score of SML group was better than that of IV group at the 6th, 9th, and 12th months (P<0.05). The decrease in the mean CMT values from baseline values was higher in SML group at the 6th, 9th, and 12th months (P<0.05). Yellow SML treatment is superior to IV anti-VEGF injection in DME patients with relatively better BCVA for increasing visual acuity and decreasing CMT at 6, 9, and 12mo. SML can be a good alternative first-line therapy for DME with BCVA ≤0.15 logMAR.

Slowed Progression of Age-Related Geographic Atrophy Following Subthreshold Laser.

PurposeTo determine the effect of panmacular low-intensity/high-density subthreshold diode micropulse laser (SDM) on age-related geographic atrophy (ARGA) progression.MethodsThe retinal images of all eyes with ARGA in a previously reported database, consisting of all eyes with dry age-related macular degeneration (AMD) active in a vitreoretinal practice electronic medical record (EMR), were identified and analyzed to determine the velocity of radial linear ARGA progression during observation and after panmacular SDM.ResultsSixty-seven eyes of 49 patients with ARGA, mean age of 86 years were identified as having follow-up both before and after initiation of SDM treatment. All were included in the study. These eyes were followed a mean 910 days (2.5 years) prior to SDM treatment and a mean 805 days (2.2 years) after. Measurement masked to treatment vs observation found the radius of ARGA lesions progressed 1 to 540 µm per year (mean 137µm, SD 107) prior to treatment (controls); and −44 to 303 µm per year (mean 73µm, SD 59) after initiation of periodic panmacular SDM laser. Thus, the velocity of radial linear progression decreased 47% per year following panmacular SDM (p<0.0001). There were no adverse treatment effects.ConclusionIn cohort of eyes with high-risk dry AMD, panmacular SDM slowed linear radial ARGA progression velocity 47% per year (p<0.0001) without adverse treatment effects. Validated, these findings would constitute an important advance in the prevention of age-related visual loss and a benchmark for future therapies.

Subthreshold Micropulse Laser in Diabetic Macular Edema: 1-Year Improvement in OCT/OCT-Angiography Biomarkers

PurposeThe aim of this study was to evaluate 1-year quantitative changes in specific inflammatory parameters on optical coherence tomography (OCT) / optical coherence tomography angiography (OCTA) in diabetic macular edema (DME) treated with subthreshold micropulse laser (SMPL).MethodsThirty-seven patients / eyes with previously treatment-naïve DME treated with SMPL were prospectively evaluated at 3, 6, and 12 months. Fifteen fellow eyes with only microaneurysms (MAS) not eligible for treatment were controls. Evaluated OCT / OCTA parameters included: central macular thickness (CMT); hyper-reflective retinal spots (HRS); disorganization of inner retinal layers (DRILs); MA in the superficial / deep capillary plexuses (SCP/DCP); cysts in the area at the SCP / DCP; and macular perfusion parameters (MATLAB, version 2017b).ResultsIn the treated group, mean best corrected visual acuity (BCVA) progressively increased from 69.4 ± 12.0 to 76.0 ± 9.1 Early Treatment Diabetic Retinopathy Study (ETDRS) letters (P < 0.001) at 12 months; HRS decreased from baseline (80.75 ± 20.41) at 3 (73.81 ± 17.1, P = 0.002), 6 (69.16 ± 16.48, P < 0.0001), and 12 months (66.29 ± 18.53, P < 0.0001). MA decreased at 3 months in the DCP (P = 0.015), at 6 and 12 months in both plexuses (P ≤ 0.0007). BCVA, HRS, and MA remained stable in the controls during all follow-ups. DRIL was present in 18 of 37 patients at baseline and progressively decreased from 557.0 ± 238.7 to 387.1 ± 282.1 μm (P = 0.01). The area of cyst decreased both in the SCP (P = 0.03) and the DCP (P = 0.02). CMT and perfusion parameters did not change.ConclusionsSMPL reduced the number of HRS (sign of activated microglia cells in the retina), MA, DRIL extension, and the area of cysts. Further studies are needed to confirm these preliminary data on the anti-inflammatory effect of SMPL, and to explore the mechanism of action.Translational RelevanceThe follow-up of OCT/OCTA noninvasive biomarkers offers a unique insight in the mechanism of laser action, suggesting an anti-inflammatory effect of SMPL.

Current Pharmacological Treatment Options for Central Serous Chorioretinopathy: A Review.

Central serous chorioretinopathy (CSC) is a common cause of visual impairment in patients generally aged 20 to 60 and it is characterized by acute or chronic neurosensory detachments of the retina. Although CSC resolves spontaneously in most cases, in some patients it may cause permanent visual impairment in the working population; for this reason, several approaches, including photodynamic therapy (PDT), subthreshold micropulse laser treatment and oral mineralocorticoid receptor antagonists, have been studied as first-line treatment options for CSC. To date, half-dose PDT has provided the most encouraging results in this regard, supported by large, multicenter, randomized clinical trials such as the “Prospective Randomized Controlled Treatment Trial for Chronic Central Serous Chorioretinopathy” (PLACE) trial; however, the role of novel possible non-invasive treatment options is attracting interest. This review article aims to discuss the current pharmacological treatment options investigated for the management of CSC, including aspirin, ketoconazole, beta blockers, rifampicin and many others. In particular, further evidence about oral mineralocorticoid receptor antagonists, firstly seen as promising non-invasive alternatives for treating CSC, will be provided and discussed in light of the recent “Eplerenone for chronic central serous chorioretinopathy in patients with active, previously untreated disease for more than 4 months” (VICI) trial results, which have largely resized their role as possible first-line oral treatment options for treating CSC.

The efficacy of subthreshold micropulse yellow laser (577 nm) in chronic central serous chorioretinopathy.

Central serous chorioretinopathy (CSC) is a disease characterized by a well-defined serous detachment of the neurosensory retina. Therapeutic options in chronic cases are limited, and side effects can result in a limited response. The aim of this article is to assess the efficacy of subthreshold micropulse laser therapy in patients with chronic central serous chorioretinopathy. The study included 20 eyes of 19 patients who had a history of chronic or chronic recurrent CSC and who underwent subthreshold micropulse laser therapy between January 2015 and June 2018. Twenty eyes of 19 patients with a mean age of 48.9 ± 9.40 years were included. The mean visual acuity was 0.24 ± 0.28 logMAR before laser, 0.19 ± 0.25 logMAR 3 months after laser, and 0.18 ± 0.27 logMAR after 6 months. A statistically significant difference was determined in terms of visual acuity before and after treatment (p = 0.0001). The mean central retinal thickness was 308.10 ± 95.25 μm before laser, 233.65 ± 81.17 μm 3 months after laser, and 203.88 ± 72.79 μm at 6 months. A statistically significant relationship was present between visual acuity and the duration of disease (p = 0.001), between visual acuity and the outer nuclear layer thickness (p = 0.005), and between the outer nuclear layer thickness and the duration of disease in chronic cases (p = 0.008). There was no evidence of retinal pigment epithelium or retinal damage on optical coherence tomography or fundus autofluorescence secondary to subthreshold micropulse laser therapy. Visual acuity appears to be more associated with the duration of disease and with changes in the outer nuclear layer thickness in chronic CSC. Subthreshold micropulse laser therapy seems to be effective at treating chronic CSC, while it increases success during early period of the disease before the development of permanent retinal damage.

Photodynamic therapy and subthreshold micropulse laser treatment - A novel combined approach for the treatment of serous retinal detachment in dome-shaped macula.

Dome-shaped macula (DSM) is characterized by an inward convexity of the macula in myopic eyes, as visualized on optical coherence tomography (OCT). Serous retinal detachment (SRD) is a common complication of DSM, leading to a deterioration of visual acuity, in association with retinal pigment epithelium (RPE) atrophic changes. Many different therapeutic approaches to SRD secondary to DSM have been attempted, with variable results. We report our experience (11 treatment-naïve patients) with a combined new treatment approach, using half-fluence and half-dose photodynamic therapy (PDT) followed by subthreshold 577 nm micropulse laser treatment (STLT), for SRD related to DSM after a 6-month follow-up. Central foveal thickness was significantly decreased at the end of the follow-up. SRD diminished in all cases, and 5 eyes (45.4 %) registered complete resolution at the end of the 6-month follow-up, while 6 eyes (54.5 %) experienced two lines of improvement in BCVA at the end of the follow-up. No case showed postoperative complications. Therefore, this represents the first study evaluating the visual and anatomical outcomes of a safe and effective combined treatment of SRD in DSM.

Analysis of choriocapillaris perfusion and choroidal layer changes in patients with chronic central serous chorioretinopathy randomised to micropulse laser or photodynamic therapy

PurposeThe purpose of this study was to investigate the signal changes in choriocapillaris flow deficits and choroidal thickness changes using swept-source optical coherence tomography angiography (OCTA) following different treatments.DesignA double-blind,...

Laser treatment in retinitis pigmentosa-a review.

Retinitis pigmentosa (RP) is a common inherited retinal disease for which effective treatment is not yet known. This review sought to analyze the available medical literature covering the efficacy of different forms of laser treatment for RP in laboratory and clinical trials. The PubMed database was searched using the following phrases: "laser photocoagulation", "subthreshold laser", "nanolaser", "micropulse laser", "retinitis pigmentosa", "rod-cone dystrophy", and "retinal dystrophy". Results were stratified as clinical or experimental studies. Six studies involving animal models and three studies involving human subjects that examined laser treatment in RP were found. Laboratory studies on rodents favored classic laser photocoagulation as the most effective therapy for slowing the progression of proto-oncogene tyrosine-protein kinase MER-related RP. Two clinical studies on humans suggested transient but robust functional benefits of subthreshold micropulse laser treatment in RP. The available material is too scarce to define laser treatment as a standard procedure to treat RP in humans. Nondamaging retinal laser therapy should be tested more intensively in clinical trials as there is no proven negative side effect of that treatment and the theoretical background, especially the chaperone and reparative roles of heat shock proteins elicited during the procedure, supports this form of RP management.

Subthreshold yellow micropulse laser for treatment of diabetic macular edema: Comparison between fixed and variable treatment regimen.

To compare the efficacy between fixed and variable treatment regimens of subthreshold yellow micropulse laser for the treatment of diabetic macular edema. This is a retrospective, comparative, 12-month study of 39 eyes: 24 eyes received fixed treatment regimen of subthreshold micropulse laser treatment and 15 eyes underwent variable treatment regimen of subthreshold micropulse laser, all eyes were followed up for 12 months. Subthreshold micropulse laser was performed with the following parameters: 100 μm spot size on slit lamp, 5% duty cycle of 0.2 s, and 250 mW power. To choose the power of the variable treatment regimen of subthreshold micropulse laser group, continuous laser power was titrated to a barely visible burn and then switched to MicroPulse mode, multiplying the test burn power by 4 and using a 5% duty cycle of 0.2 s. Main outcomes included changes in central macular thickness and best-corrected visual acuity. At baseline, the mean LogMAR best-corrected visual acuity was 0.297 ± 0.431 in the variable treatment regimen of subthreshold micropulse laser group and 0.228 ± 0.341 in the fixed treatment regimen of subthreshold micropulse laser group. At the end of follow-up, the mean LogMAR best-corrected visual acuity was 0.289 ± 0.473 (p = 0.785) and 0.245 ± 0.376 (p = 0.480) in the variable and fixed treatment regimens of subthreshold micropulse laser groups, respectively. Similarly, central macular thickness decreased in both groups after treatment; at baseline, the mean central macular thickness was 371.06 ± 37.8 in the variable treatment regimen of subthreshold micropulse laser group and improved to 325.60 ± 110.0 μm (p = 0.025) at the end of the follow-ups, while it was 342.30 ± 35.4 in the fixed treatment regimen of subthreshold micropulse laser group and improved to 308.51 ± 67.5 (p = 0.037). Both treatment regimens are effective for the treatment of mild center-involving diabetic macular edema: fixed treatment appears more suitable minimizing treatment time and reducing the possible errors due to wrong titration in the switch from continuous to micropulse mode.

Crossover to Photodynamic Therapy or Micropulse Laser After Failure of Primary Treatment of Chronic Central Serous Chorioretinopathy: The REPLACE Trial

To assess whether chronic central serous chorioretinopathy (cCSC) patients without a complete resolution of subretinal fluid (SRF) after either half-dose photodynamic therapy (PDT) or high-density subthreshold micropulse laser (HSML) treatment may benefit from crossover treatment. Multicenter prospective interventional case series. cCSC patients with persistent SRF at the final visit of the PLACE trial were included. Patients received crossover treatment with either half-dose PDT or HSML. Thirty-two patients received PDT and 10 patients received HSML. At the first evaluation visit (6-8weeks after treatment), 81% of patients in the PDT group had complete resolution of SRF, while none of the HSML-treated patients had complete resolution of SRF. At final visit (1 year after baseline), 78% (P= .030) and 67% (P= .109) of the patients, respectively, had a complete resolution of SRF. The mean retinal sensitivity in the PDT group increased from 21.7 dB (standard error [SE]: 0.9) to 23.4 dB (SE: 0.8) at evaluation visit 1 (P= .003), to 24.7dB (SE: 0.8) at final visit (P < .001), while there were no significant changes in the HSML group (23.7 dB [SE: 1.6] at baseline, 23.8 dB [SE: 1.4] at evaluation 1, and 23.3 dB [SE: 1.4] at final visit). The mean visual acuity and mean visual quality-of-life questionnaire score did not change significantly in both groups. Crossover to half-dose PDT after previous unsuccessful HSML treatment for cCSC may lead to improved anatomic and functional endpoints, while crossover to HSML after half-dose PDT does not seem to significantly affect these endpoints.

Subthreshold Diode Micropulse Laser (SDM) for Persistent Macular Thickening and Limited Visual Acuity After Epiretinal Membrane Peeling.

PurposeTo examine the effect of low-intensity/high-density subthreshold diode micropulse laser (SDM) on visual acuity (VA) and macular thickness in eyes with limited visual recovery and persistent macular thickening after epiretinal membrane peeling.MethodsA retrospective review of medical records identified all patients undergoing SDM after membrane peeling in a clinical vitreoretinal subspecialty practice. Exclusion criteria included other obfuscating ocular disease or loss to follow-up after SDM treatment.ResultsAll 19 eyes of 18 patients identified were included for study. After membrane peeling, VA improved from an avg. Snellen 20/240 [logMAR 1.08] to 20/72 [0.56] (p=0.0004). Attributed to persistent macular thickening following membrane peeling, overall VAs then gradually declined to an avg. of 20/91 [0.66] by 4−109 months (avg. 41) post vitrectomy, at which point panmacular SDM was performed. An avg. 15 months post SDM, both VA (to avg. 20/68 [0.53]) and maximum macular thickness improved (p=0.007 and p=0.008, respectively). There were no adverse treatment effects.ConclusionLow-intensity/high-density subthreshold (sublethal) diode micropulse laser (SDM) may reduce macular thickening and improve visual in eyes with persistent macular thickening after membrane peeling even years after vitrectomy.