Sir,
We thank Tan et al1 for their comments and questions, which provide us with a chance for further clarification of our study outcome. The comment we included in the discussion mentioning ‘80% rate in polyp eradication at 1 year' means disease quiescent state by treatment with photodynamic therapy and Lucentis injections.2 We agree that complete thrombosis and disappearance of polyps is not commonly seen after treatment with either photodynamic therapy or even combined with Lucentis injection; however, turning active polypoidal lesions into inactive ones are achievable treatment goals. Hence, we would like to emphasize the efficacy of combination therapy by eradicating 80% of actively leaking polyps.
We congratulate Tan et al in successfully describing the different subtypes of polypoidal choroidal vasculopathy (PCV) vasculature and in successfully relating the vasculature pattern with the disease outcome.3 We hypothesize that the described subtypes of PCV from types A–C may present as a continuum of disease where type C, being the most severe form of PCV, shows the most prominent vascular networks. We agree with the authors that type C is related to poor outcome as it likely represents a late stage of vascular channel development, which is prone to leakage and haemorrhage. We would like to supplement that, apart from the characteristics of choroidal vasculature, the location of dilated interconnecting vascular network is also a detrimental factor affecting visual outcome.2
In assessing PCV, ICG provides vital pieces of information that could help predict the outcome of disease. As PCV is a disease entity with diversified clinical outcomes,4 we agree that it is important to pay attention to disease subtypes, which would provide guidance towards choosing the most suitable treatment in each unique case.
The authors declare no conflict of interest.
References
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