Response to comments on “Intravitreal triamcinolone acetonide therapy in serpiginous-like choroiditis”

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Dear Editor, We thank the author for the appraisal of our article[1] and the opportunity to clarify several methodological aspects. We acknowledge that the retrospective, single-center design has inherent limitations, which were recognized in the manuscript. A minimum follow-up of 6 months was intentionally required to allow assessment of lesion resolution, recurrence, paradoxical worsening, and drug-related adverse effects. To address the concern regarding attrition bias, we reviewed the records of the 18 excluded cases. Ten cases were lost to follow-up in a few days after intravitreal triamcinolone acetonide (IVTA), while the remaining eight with follow-up ranging from 0.5 to 5 months showed no documented "evidence of" early treatment failure or serious IVTA-related complications [Table 1]. In several eyes, early clinical or fundus autofluorescence (FAF)-based improvement was already evident within the limited follow-up period, consistent with the reported cohort.[1]Table 1: Demographics, clinical pattern, and treatment outcomesSerpiginous-like choroiditis (SLC) may demonstrate morphological variability.[2,3] In our study, stratified analyses were not feasible due to the small sample size, uneven morphological distribution (nine dendritic, four placoid, two peripheral placoid SLC), and variable areas of lesion.[1] Subgroup comparisons would therefore have been underpowered and potentially misleading. The heterogeneity in antitubercular therapy (ATT) timing, absence of ATT (3/14 cases), and oral steroid use (4/14 cases) reflects real-world management in tuberculosis (TB)-endemic settings. Patients receiving oral corticosteroids were on tapering doses not exceeding 20 mg at the time of IVTA. In most cases (8/11 cases), ATT was initiated days to weeks after IVTA, a pattern also observed among the excluded cases [Table 1]. Our finding of the absence of paradoxical worsening should be taken in context with the cases receiving ATT (11/14). We acknowledge that indication-based use of IVTA may have introduced confounding by indication; however, the predominant indication was foveal involvement (12/15 eyes) in our study. The single patient receiving azathioprine had started the therapy elsewhere and taken for only 1 week prior to IVTA; therefore, the drug would not yet have achieved therapeutic immunomodulatory effect. The selected outcomes, clinical and FAF-based lesion resolution, paradoxical worsening, recurrence, and need for repeat IVTA were chosen for their clinical relevance in monitoring SLC activity. We acknowledge that the retrospective design and small sample size did not allow a predefined endpoint or formal sample size calculation; therefore, the analysis was primarily descriptive rather than providing precise estimates of recurrence or paradoxical worsening. Best corrected visual acuity (BCVA) was converted to logMAR and analyzed using a paired t-test. Although the BCVA numerical gain appears modest, in macula-threatening disease, stabilization or modest improvement may still represent meaningful functional preservation. Subgroup analyses based on lesion location or macular edema were also not possible in this small series. Inclusion of additional functional measures such as visual field assessment would have been a better parameter, but it is not routinely advised in SLC patients at our center. Recurrence was reported descriptively because the small sample size did not permit meaningful comparative statistical analysis. The suggestion that ATT may reduce recurrence was based on prior literature rather than solely on the present study. Our findings primarily indicate that IVTA can help abort active lesion progression in the initial phase, even before ATT is commenced. The study was not powered to demonstrate a reduction in paradoxical worsening, and therefore, no statistical inference regarding risk reduction can be made. In our small, noncomparative cohort, the absence of paradoxical worsening in all 11 cases that received both ATT and IVTA was a noteworthy observation. The interpretation that IVTA monotherapy was proposed to “safely abort lesions without ATT” requires clarification. In our study, the lesions in the IVTA-only eyes initially responded and healed following injection. The two events reported were late relapses occurring 5–7 months after IVTA, rather than failure of lesion control. These events represent late recurrence after the effect of IVTA had waned. The observed rates of intraocular pressure (IOP) elevation and posterior subcapsular cataract are consistent with the known safety profile of intravitreal corticosteroids and comparable to reports with dexamethasone implants in SLC.[4] All IOP elevations were medically controlled, and none required laser or surgical intervention. Review of the excluded cases also did not reveal uncontrolled IOP rise [Table 1]. The manuscript does not portray low-dose IVTA as risk-free but as a targeted local therapy that may reduce systemic steroid exposure in selected patients. The principal novelty of this study lies in reporting outcomes with low-dose (2 mg) IVTA in SLC in a TB-endemic setting, delayed ATT commencement with respect to IVTA, and the absence of paradoxical worsening in all receiving ATT. Recent evidence also highlights the importance of early and adequate immunosuppression in SLC. Kesav et al.[5] demonstrated that a higher cumulative immunosuppressive load in the first month reduces persistent inflammation at completion of ATT. Localized corticosteroid delivery such as IVTA may therefore complement systemic therapy. Prospective controlled, larger multicentric studies with standardized protocols are needed, and we hope our findings provide preliminary real-world data to plan such studies. Financial support and sponsorship: Nil. Conflicts of interest: There are no conflicts of interest.