AIM: To comparatively analyze the efficacy of subthreshold laser photocoagulation with the NAVILAS^® Laser system and subthreshold micropulse laser for patients with chronic central serous chorioretinopathy(cCSC).

METHODS: A retrospective clinical study. A total of 36 patients(40 eyes)with cCSC were recruited from January 2020 to January 2021 diagnosed at the Affiliated Eye Hospital of Nanjing Medical University. There were 19 patients(23 eyes)treated with subthreshold navigated laser photocoagulation(the Navilas group), and 17 patients(17 eyes)treated with subthreshold micropulse laser(SML)(the SML group). There was no significant difference in baseline data between the two groups(P>0.05). The best corrected visual acuity(BCVA, LogMAR), central macular thickness(CMT), subretinal fluid(SRF)height, vessel densities of the superficial capillary plexus(SCP), the deep capillary plexus(DCP)and area of the foveal avascular zone(FAZ)were collected at 2wk, 1, 3 and 6mo before and after treatment.

RESULTS: The BCVA of the two groups were significantly higher than that before treatment at 3 and 6mo after surgery(P<0.05),which was significantly reduced at 2wk after treatment in the Navilas group and was reduced at 1mo after treatment in the SML group(P<0.05). In both groups, there was significant decrease compared with that before treatment at 3 and 6mo after treatment(P<0.05),but there was no significant difference between the two groups(P>0.05). The difference in SRF absorption between the two groups was statistically significant(P<0.05), and the complete absorption rate of SRF in the Navilas group was higher than that in the SML group. SCP, DCP, the area of the FAZ were not significantly different from each time ofbaseline in the two groups(P >0.05).

CONCLUSION: Subthreshold laser photocoagulation with the NAVILAS^® Laser system can rapidly improve the retinal morphology and shorten the course of cCSC to improve the recovery of visual function with its rapid effect, high cost-effectiveness, non-invasiveness and high repeatability, which can be a new clinical method for patients with cCSC.