RESUMO
Laser photocoagulation is one of the important methods for treating retinal diseases, and retinal laser technology continues to advance. For decades, researchers have been striving to find a laser treatment that can minimize tissue damage while achieving optimal results. With low toxicity, low scattering light, strong penetrating power, small compared with the traditional laser damage, light reaction and no pain, the 577 nm subthreshold micropulse laser(SML)turns this goal into reality and ushers in a new era of laser treatment for fundus diseases. This article reviews the concept, mechanism, related parameters and clinical application progress of 577 nm SML in a variety of retinal diseases, aiming to provide references for clinical treatments.
RESUMO
AIM: To analyze the clinical effect of 577nm subthreshold micropulse laser(SML)photocoagulation combined with intravitreal injection of Conbercept in the treatment of diabetic macular edema(DME)after vitrectomy in patients with proliferative diabetic retinopathy(PDR).METHODS:A retrospective analysis was performed on 29 cases(30 eyes)of PDR patients who had DME after vitrectomy in our hospital from January 2019 to June 2021. They were divided into two groups according to different treatment methods: 14 cases(14 eyes)in the single injection group received intravitreal injection of Conbercept, and 15 cases(16 eyes)in the combined treatment group received 577nm SML photocoagulation in the macular area combined with intravitreal injection of Conbercept. The changes in best corrected visual acuity(BCVA)and central macular thickness(CMT)before and at 6 and 12mo after treatment, as well as the changes of multifocal electroretinogram(mfERG)before and at 12mo after treatment were compared between the two groups.RESULTS: The BCVA(LogMAR)of patients in both groups improved and CMT decreased after treatment for 6 and 12mo(all P<0.001). There were no significant differences in BCVA(LogMAR)and CMT before treatment and 6mo, 12mo after treatment between single injection group and combined treatment group(all P>0.05). Compared with the combined treatment group, the amplitude was slightly lower(23.02±3.13 vs. 26.50±3.33 μV/deg2)and the latency time was prolonged(38.75±1.62 vs. 34.21±3.06ms)in single injection group at 12mo(all P≤0.001). The average injection times in single injection group was 8.14±1.46, and 5.05±1.51 in combined treatment group at 12mo after treatment(P<0.05).CONCLUSION: 577nm SML photocoagulation combined with intravitreal injection of conbercept can effectively relieve macular edema, improve BCVA and visual function of macular area and reduce the injection times of conbercept for DME patients.
RESUMO
@#AIM: To compare the efficacy and safety of 577nm subthreshold micropulse laser(SML)and photodynamic therapy(PDT)in patients with chronic central serous chorioretinopathy(cCSC).<p>METHODS: Thirty patients(30 eyes)with cCSC were treated in our hospital from February 2015 to April 2018. And 15 patients(15 eyes)were treated with SML(577 nm)while the others were treated by PDT. The BCVA and CMT as well as complications were observed at 1, 3, 6mo after treatment.<p>RESULTS: At 1mo after treatment, BCVA was increased to 0.37±0.13 in SML group and 0.20±0.11 in PDT group(<i>t</i>=-3.93, <i>P</i><0.001); CMT was decreased to 382.80±76.54μm in SML group and 247.60±28.46μm in PDT group(<i>t</i>=-6.41, <i>P</i><0.001). Although improvements of BCVA and CMT were both achieved in two groups, improvements in PDT group were better than those in SML group. At 3mo and 6mo after treatment, both BCVA and CMT were no significant difference between the two groups(<i>P</i>>0.05). During the follow-up period, there were no obvious complications or recurrence observed.<p>CONCLUSION: Both SML(577nm)and PDT were effective and safe in the treatment of cCSC, but the theraputic effects of PDT was slightly quicker than SML. Further, with the prolongation of recovery time, the curative effects of these treatments were similar. Additionally, SML(577nm)costs was much cheaper than PDT and had no risk of injury or allergy for patients, and patients with cCSC could also be treated repeatedly using it.