Central serous chorioretinopathy (CSCR) stands as a notable chorioretinal disorder characterized by the idiopathic detachment of the retina due to serous fluid accumulation. This pathology manifests through the emergence of one or more sites of leakage originating from the choroid, facilitated by a disruption in the retinal pigment epithelium (RPE) outer blood-retina barrier [1]. CSCR typically follows a self-limiting course, with a favorable recovery of visual function in most cases. Nevertheless, approximately 33–50% of individuals may experience recurrences, which can lead to persistent areas of neurosensory detachment and subsequent permanent visual impairment [2]. The definition of chronic CSCR duration lacks consistency across studies, with some utilizing a 3-month criterion while others opt for 6 months; our study adopts the former [3], [4]. Treatment is warranted in patients necessitating expedited visual recovery or those suffering from enduring visual impairment attributable to CSCR in the fellow eye or chronic CSCR. Various treatment modalities exist, including conventional focal laser therapy, photodynamic therapy (PDT), and intravitreal administration of drugs such as bevacizumab [5], [6], [7]. However, these interventions yield variable outcomes and are not devoid of associated risks and adverse effects. Conventional focal photocoagulation, for instance, may induce central or paracentral scotomas, contrast sensitivity reduction, inadvertent foveal injury, retinal distortion, or choroidal neovascularization [5], [6]. Moreover, treatment may be precluded in cases with a subfoveal or juxtafoveal leak.

In contrast to conventional laser therapy, subthreshold micropulse laser (SML) treatment offers a non-damaging approach, enabling direct treatment of the parafoveal or foveal regions with the potential for repeated applications without inducing detectable structural or functional damage [8]. SML entails the delivery of a series of repetitive laser pulses interspersed with intervals. This modality has been extensively investigated in clinical studies for various retinal diseases and has garnered commercial availability along with FDA approval, thus positioning SML as a viable alternative for the treatment of CSCR. Despite its reported efficacy in CSCR treatment, the parameters utilized in SML therapy have been subject to controversy [8]. Notably, investigations utilizing 577 nm micropulse lasers have been conducted, with this wavelength offering distinct advantages [9]. The 577 nm wavelength lies beyond the absorption spectrum of retinal xanthophyll and exhibits significant benefits, including optimal absorption of oxyhemoglobin, minimal xanthophyll absorption in the macula, and potentially enhanced penetration, facilitating treatment proximity to the fovea [[10], [11]].

Performing conventional laser photocoagulation for leaks in CSCR can pose challenges, particularly in accurately pinpointing the precise location of the leak amidst the intricate network of blood vessels on a dynamically moving eye. In efforts to enhance the precision and predictability of retinal laser photocoagulation in CSCR, the Navilas® laser system (OD-OS GmbH, Teltow, Germany) offers a solution by enabling treatment planning directly on early fluorescein angiograms prior to the procedure. By importing the angiogram into the laser device and continuously aligning it with the live fundus image using an eye tracking system, physicians gain the ability to execute more targeted treatments with enhanced accuracy compared to conventional manually directed laser photocoagulation [12]. The utilization of a navigated laser device alleviates the difficulty of locating the leaky spot on the live fundus view during the procedure conducted through the slit-lamp laser device. The Navilas® laser system offers several advantages, including precise leak localization, eye tracking functionality, and laser treatment planning capabilities based on fluorescein angiograms. Additionally, navigated laser photocoagulation is characterized by shorter procedural duration and reduced patient discomfort compared to conventional laser treatments. However, while the benefits of navigated laser therapy in CSCR treatment are evident, direct observation of specific morphological changes in the RPE following such treatment remains unexplored. Therefore, the aim of this study is to assess the efficacy of navigated subthreshold micropulse laser (NSML) therapy for CSCR and to compare its outcomes with those of SML therapy without navigation.